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This article was first published on May 17, 2021.

While change is the only constant in life, there are certainly periods where change is more amplified. We currently find ourselves in one of those periods. The world and our key industries are not immune to the ripple effects of the global pandemic. As an example, for the financial services industry, there are many drivers of change: in the short term, retail banks are facing downward pressures on net income due to record-low interest rates and increasing delinquency rates, and the need to trim costs quickly; in the medium term, new remote working routines are further accelerating digitization, automation, and disintermediation. As a result, business and operating models are trying to adapt to the “new normal.”

The firms able to effectively deliver change will thrive and are more likely to emerge stronger from these changes. However, as recent social science research has shown, delivering change is no easy task: humans have a natural bias against change. Failing to drive change is a challenge to the competitiveness and sustainability of any firm, creating monetary costs, eroding trust with customers and investors, and weighing on culture and employee engagement. On the flip side, firms that successfully deliver change set off a self-reinforcing feedback loop that increases profitability and productivity, builds trust with stakeholders, and attracts top talent.

An often forgotten institutional ‘muscle’ for firms is the ability to effectively manage change risk —the risk that a change program fails to deliver the desired goals. We believe that most firms do not proactively manage change risk in a way that commensurate with the benefits of success and the costs of failure. Effectively managing change risk is a necessary ‘muscle’ to reduce, preempt, mitigate, and manage the challenges that come with (intents of) transformation, without bringing decision paralysis or stifling innovation in the organization. We refer to change risk as a ‘silent risk’ because this ‘muscle’ is often neglected and, too often, that neglect is one of the root causes behind the inability to drive to the desired outcomes.

In our paper, we present an approach to proactively manage change risk, including:

• How to manage change across the end-to-end change lifecycle, to ensure firms develop fit for purpose mechanisms
• How change risk management is a key component of the journey, and the best ways to understand drivers of successful change
• Recommendation for four key change management capabilities, a change risk management framework, change delivery igniters, workforce change capacity management, and a process for initiative prioritization; and actions to help leaders make change management a priority

Below is an excerpt from the report, for the full PDF version, please click here .

Our views on successful change

Effective change boils down to directing energy and aligning efforts toward three key elements:

• The strategy and thinking
• The people and behaviors
• The underlying infrastructure

We call these elements the Head, the Heart, and the Guts of an organization. Successful change should have risk management embedded into these key elements.

Successful change occurs when the Head, the Heart, and the Guts are fully aligned, resulting in an organization that has: (1) the willingness to change—through leadership, personal drive, and the identification of strategic value; and (2) the ability to execute—through an adequate workforce, the right infrastructure, and a clear roadmap.

Too often, firms facing change tend to focus on the Head at the expense of the Guts and, especially, the Heart. Such firms often struggle to achieve successful change because lasting change requires individuals to collectively change behaviors. For example, a firm does not become more customer-centric when rolling out a new top-down campaign or training module. Rather, the firm becomes customer-centric when the workforce begins adopting customer-centric behaviors—the way customer interactions play out; the way products are configured; and the way senior leadership communicates and makes decisions.

Change is the only constant in life Heraclitus, c. 535 BCE – 475 BCE.

Experience and research indicate that, for change to occur, each level of the organization needs to understand the objectives and purpose of the change, as well as the new behaviors to adopt. Change experts across the globe call these “vital behaviors”—the smallest actions that, if consistently repeated, will lead to the intended outcomes.

In driving change , the ability to manage change risk needs to be developed in the Guts (through risk management capabilities); the Heart (through an understanding of the workforce stoppers and capacity in the firm); and the Head (through the incorporation of change risk into the firm strategy). Our research shows that, historically, neither risk managers nor front-line risk owners have paid enough attention to managing change risk. If firms believe—as we do—that a better managed change risk is a key success factor, firms must pay more attention to driving alignment between Heart, Head, and Guts in order to achieve successful change, and also appropriately embed risk management capabilities across these elements.

We have identified four capabilities for firms that can increase opportunities to drive effective change management:

1. Change risk management framework: Adapt the firm’s overall risk management framework to cover change risk across the lifecycle

2. Change igniters: Clear obstacles to build a change-oriented organization by diagnosing and addressing organizational weaknesses

3. Workforce change capacity management: Monitor change load and change fatigue, as well as improve organizational agility

4. Initiative prioritization: Develop a process for assessing change initiatives to maximize impact within change capacity

We believe firms that achieve these four capabilities will see an increased efficacy and decreased risk associated with the change programs. Returning to the change lifecycle in the exhibit below, we show how these capabilities can reinforce each stage and broaden the role risk management teams play well beyond the implementation and go-live steps.

Actions for effective change risk management

Given both, the necessity of achieving successful change in the current tumultuous world and the high cost of failure, organizations cannot afford to take a reactive or narrow approach to change risk management.

We recommend front-line and risk management leaders:

Overall, firms that succeed in incorporating change risk management into processes and culture will become more agile and more resilient, while firms that lag will run the risk of being caught flat-footed when the next disruption arrives. Firms that proactively manage change risk will be able to overcome the silent risk that hinders growth and emerge as winners.

The authors would like to acknowledge and thank Jonathan Lee and Rutger von Post for their contributions to this paper.

• Financial Services
• Risk Management for Financial Services
• Ramy Farha,
• Chris DeBrusk, and
• Antonio Tugores

Striving For Operational Resilience: The Questions Boards And Senior Management Should Ask

Operational resilience has become a key agenda item for boards and senior management. Increasing complexity in processes and IT, dependence on third parties, interconnectedness and data sharing, and sophistication of malicious actors have made disruptions more likely and their impact more severe. High-profile examples of business and operational disruptions abound, covering all segments of the financial services industry.

Non-Financial Risk Convergence And Integration

Non-Financial Risk Management has become more complex due to rapid shifts in technology, automation and greater dependence by banks on systems instead of people.

How to Conduct Change Management Risk Assessment

Are you preparing to transition your organization or team through a period of significant change?

With any change comes some inherent risk, which can be both exciting and anxiety provoking.

To ensure the success of such an endeavor it’s important to plan for, mitigate and manage risks as they arise throughout the process.

In this blogpost we’ll discuss why business leaders and managers needs to pay attention to potential risks and learn how to conduct change management risk assessment in order to execute a successful transition.

What is Change Management Risk?

The factors which can negatively affect achieving desired change outcome, primarily due to insufficient planning or lack of change-readiness among stakeholders.

Change management risk can lead to delays in implementation and results, increased costs and compromised quality standards, ultimately impacting an organization’s bottom line.

It is essential for organizations to mitigate change management risks by creating a clear change strategy with well-defined objectives, monitoring change goals and gathering feedback from stakeholders along the way.

Why it is important to identify change management risk?

Change is inherent in any business, and change management can be challenging. Adequately assessing change management risks helps to minimize unexpected outcomes, increases efficiency and effectiveness, and bolsters the flexibility of organizational processes.

It is essential that organizations acknowledge the need to identify change management risks, as failure to do so may lead to project delays, budget overruns and costly repair work.

By critically diagnosing change management risk associated with specific projects or events, an organization is better equipped to develop tailored strategies for successful change implementation. Ultimately, change management risk identification is a critical step for ensuring key change objectives are met on time and within budget.

Change Management Risk Assessment

Change management risk assessment is a crucial process for organizations to mitigate the risks associated with change. It involves looking at potential change initiatives, and examining how they may affect an organization’s resources and operations.

The results of change management risk assessment allow us to make well-informed decisions on the implementation and potential success of change initiatives.

To successfully complete change management risk assessment, it is important to determine objectives, analyze relevant data sources, identify risks and their root causes, and create viable response plans.

This is ultimately done through establishing processes that help organizations develop stability during a time of transition, enabling them to achieve successful outcomes more efficiently.

04 Steps to Conduct Change Management Risk Assessment

In order to conduct change management risk assessment, there are several key steps that need to be taken.

Step 1: Define change management risk assessment framework

It is important to have a clear understanding of what the change initiative is aiming to accomplish, as this will inform the risk assessment process. During this step, it is also important to establish a change management risk assessment framework. This framework should provide the foundation for identifying change management risks and understanding their potential impact on the organization.

The change management risk assessment framework should be tailored to the specific change initiative and take into account any existing organizational change processes. This will ensure that all stakeholders are fully aware of the change objectives, can recognize change management risks, and have an understanding of the steps needed to effectively address risk.

Step 2: Analyze data

The second step to conducting change management risk assessment is to analyze data sources. This involves gathering information from a variety of sources such as internal documents, reports, and interviews with stakeholders. It is important to identify the key change components and assess their potential impacts in order to recognize change management risks.

Through data analysis, organizations can gain greater insight into change management risks and their impacts on their operations. Data analysis allows organizations to identify change management risks and the underlying causes, evaluate the solutions available to them, and make informed decisions when managing change initiatives.

Step 3: Identify and analyze risks

The third step to conducting change management risk assessment is to analyze the change management risks identified. This involves understanding their root causes and evaluating their potential impacts on the organization. It is important to identify any assumptions, dependencies, or interdependencies that could affect change management risk assessment outcomes.

Organizations should also assess whether existing change processes are adequate enough toeffectively manage change risk. This includes considering the impact that change initiatives will have on existing structures, processes and systems, as well as understanding the resources available to address change risks.

Step 4: Develop response plans

The next step to conducting change management risk assessment is to develop response plans. This involves formulating strategies and tactics to mitigate change risks, as well as determining possible contingencies in the event that change initiatives do not succeed. During this stage, organizations should identify resources necessary for successful change implementation, such as personnel and technology.

It is important to prioritize change management risks in order to ensure that the most critical risks are addressed first. This involves understanding the potential impact of each change risk on the organization, and identifying which risks should be addressed to mitigate their effects.

What are common risks of change management

Following are some common risks of change management:

lack of understanding or buy-in from stakeholders

The lack of understanding or buy-in from stakeholders is one of the most common change management risks. This risk can arise when stakeholders are not fully aware of change objectives, or do not agree with the change initiatives being undertaken. In such cases, stakeholders may resist change initiatives or take actions that undermine their success.

Inadequate change management practices and processes

Inadequate change management practices and processes can also be a major risk to change initiatives. Organizations must ensure that change strategies are understood, agreed upon, and implemented effectively in order to maximize the chances of change success. Without an effective change management process in place, organizations may find themselves unable to adjust quickly enough to address risks.

Ineffective communication

Organzations often make mistake by having one-way communication with employees and other stakeholders. This is one of the biggest risk of change management. Change is not successful if its message is only coming from top and voices of employees or other stakeholders are unheard. If organizational culture fails to exchange ideas and share experience then it’s hard to implement transformative change.

An excessive change implementation timeline

An excessive change implementation timeline can pose a serious risk to change management, as it often leads to delays, slowdowns, and potential abandonment of change initiatives. When change initiatives take too long to implement, they can become costly and complex affairs that may not yield the desired results.

Inadequate change control measures

Inadequate change control measures are one of the most common change management risks. These typically arise when change initiatives are not reviewed and approved on a timely basis. Without proper change control mechanisms in place, change initiatives can go unchecked and progress without proper risk assessment and validation.

Misaligned change initiatives with organizational objectives

Misaligned change initiatives with organizational objectives can be a major change management risk. When change initiatives are not in alignment with the organization’s overall goals and objectives, they can lead to wasted resources, reduced efficiency, and even failure of the change initiative.

Final Words

Assessing risks is a key component of successful change management. By understanding what could go wrong and taking steps to mitigate those risks, you can increase the chances of your change initiative being successful. There are many different ways to assess risks and some common risks associated with change management initiatives include resistance to change, lack of resources etc. By taking the time to understand these risks and develop a plan to address them, you can set your change initiative up for success. Do you have a plan in place to assess risks to your change management initiative? What are some of the most common risks you’ve encountered during past initiatives?

About The Author

Tahir Abbas

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Change Strategists

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Are you in the process of making changes within your organization? Whether it’s a new software implementation or a company-wide restructuring, change can bring about uncertainty and risk. It’s important to identify and mitigate these risks to ensure a smooth transition and minimize potential negative impacts.

Effective risk management is essential for any successful change process. By conducting a thorough risk assessment, developing a mitigation strategy, and implementing and monitoring risk controls, you can identify potential issues before they become major problems.

In this article, we will provide you with a step-by-step guide on how to identify and mitigate risks during the change process. By following these guidelines, you can ensure that your change process is successful and your organization can thrive in the long run.

Understanding the Importance of Risk Management

You gotta know that managing risk is crucial when making any changes. As you move forward with a change process, there are a lot of uncertainties and potential pitfalls that could arise. That’s where risk identification comes in.

By analyzing the potential risks associated with the change, you can better prepare for them and minimize their impact on the project. Once you’ve identified the potential risks, it’s important to develop risk mitigation techniques.

This means coming up with a plan to reduce the likelihood or impact of each potential risk. For example, if you’re implementing new software, you might identify the risk that the system could crash during the implementation process. A mitigation technique for this risk might be to conduct thorough testing before rolling out the new software to ensure it’s stable.

Effective risk management requires ongoing attention throughout the change process. You can’t just identify the risks and develop mitigation techniques at the beginning of the project and call it good. You need to consistently monitor and reassess the risks as the project progresses.

This will allow you to adjust your mitigation techniques as needed and ensure that you’re always prepared for any potential risks that may arise.

Conducting a Risk Assessment

Now that you’ve gathered all necessary information, it’s time to assess potential hazards and determine the likelihood of negative outcomes. Conducting a risk assessment is crucial in identifying common risks and minimizing their impact on your change process. Here are a few tips to help you conduct a successful risk assessment:

• Use risk assessment tools : There are various tools available to assess risks, such as SWOT analysis, PEST analysis, and FMEA. These tools help you identify the strengths, weaknesses, opportunities, and threats of your change process. They also help you identify potential risks and develop strategies to mitigate them.
• Involve stakeholders : Your stakeholders have valuable insights that can help you identify potential risks. Involve them in the risk assessment process to gain a better understanding of the potential challenges and their impact on the change process. This will also help you gain their support for the change.
• Prioritize risks : Not all risks are equal in terms of their impact on the change process. Prioritize the risks based on their likelihood and severity. This will help you focus on the most critical risks and develop strategies to mitigate them.

By conducting a risk assessment, you can identify potential hazards and develop strategies to mitigate them. This will help you minimize the impact on your change process and ensure its success. Remember, risk management is an ongoing process, and you should regularly review and update your risk assessment to ensure its effectiveness.

Developing a Mitigation Strategy

In the current section, we’ll be developing a plan to minimize the negative impact of potential hazards on our change goals. Change management is not just about identifying risks but also about developing a mitigation strategy to respond to them. This is where risk response comes in. Risk response involves developing a plan to mitigate the impact of risks on the change process.

To develop a mitigation strategy for potential hazards, it is important to understand the different types of risks that might occur during the change process. You can do this by conducting a thorough risk assessment, which we have discussed in the previous subtopic. Once you have identified the different types of risks, you can then begin to develop a mitigation strategy that addresses each risk.

A useful way to develop a mitigation strategy is to use a table that outlines each risk, its potential impact, and the actions that can be taken to mitigate it. This table can be used as a reference throughout the change process to ensure that all risks are being addressed. By taking a proactive approach to risk management, you can ensure that your change process is successful and that any potential hazards are minimized.

Implementing and Monitoring Risk Controls

We’ll now focus on putting our plan into action to ensure that any potential issues are kept in check. After developing a mitigation strategy, it’s crucial to implement and monitor risk controls to ensure their effectiveness.

Implementing risk controls means applying the plans and actions outlined in the mitigation strategy. This includes assigning tasks to team members, creating a timeline for completion, and ensuring that everyone is aware of their responsibilities.

Continuous monitoring is essential to ensure that risk controls are effective. It involves regularly checking whether the risk controls are working as intended and if any new risks have emerged. Monitoring can be done through regular meetings with team members, reviewing progress reports, and conducting risk assessments.

Monitoring can also help identify areas for improvement in the risk controls and provide an opportunity to adjust the mitigation strategy if necessary.

In summary, implementing and monitoring risk controls is crucial in identifying and mitigating potential risks during the change process. By putting the mitigation strategy into action and continuously monitoring the effectiveness of risk controls, organizations can reduce the likelihood of issues arising. This approach ensures that the organization is well-prepared to handle any unforeseen challenges that may arise during the change process.

Creating a Contingency Plan for Unforeseen Circumstances

Preparing for the unexpected is like having a safety net – it’s important to have a contingency plan in place to handle any unforeseen circumstances that may arise during the implementation of the risk controls.

Contingency planning involves identifying potential risks and developing risk response strategies to mitigate them. This process helps to ensure that the project stays on track and that any unexpected events are handled effectively.

A contingency plan should include a detailed description of potential risks and how they will be addressed. This plan should also identify the key stakeholders who will be responsible for executing the plan and specify the timeline for implementation.

In addition, the contingency plan should outline the communication strategy for informing all stakeholders of the unforeseen circumstances and the actions that will be taken to address them.

In summary, creating a contingency plan is an essential part of managing risks during the change process. It helps to ensure that the project stays on track and that any unforeseen circumstances are handled effectively. By identifying potential risks and developing risk response strategies, you can mitigate the impact of unexpected events and ensure the success of your project.

How Can Effective Change Communication Mitigate Risks During the Change Process?

Effective change communication planning insights can help mitigate risks during the change process by keeping all stakeholders informed and engaged. Clear and timely communication can address concerns, manage expectations, and foster support for the change. By providing relevant information, addressing potential resistance, and ensuring transparency, communication planning insights can help minimize disruptions and maximize successful change implementation.

In conclusion, managing risks during the change process is a critical task that requires your utmost attention. By conducting a thorough risk assessment, you can identify potential risks and develop a mitigation strategy that will help reduce the likelihood of these risks occurring.

This will ensure that your change process runs smoothly and efficiently, with minimal disruption to your organization. However, it’s important to remember that risks are an inevitable part of any change process, and it’s impossible to eliminate them entirely.

Therefore, it’s essential to implement and monitor risk controls, and to create a contingency plan for unforeseen circumstances. As the saying goes, “expect the best, but prepare for the worst.” By taking a proactive approach to risk management, you can minimize the impact of any unforeseen events and ensure that your change process is successful.

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Explore the Levels of Change Management

The Costs and Risks of Poorly Managed Change

Tim Creasey

Updated: March 2, 2024

Published: January 19, 2022

When the people side of change is ignored or poorly managed, the project and the organization take on additional costs and risks. When you consider it from this perspective, effective change management is a cost avoidance technique, risk mitigation tactic, and justifiable investment . Here's an overview of common costs and risks, and how to position change management to clearly communicate and share its benefits.

Consequences of Poor Change Management

It's likely that we have all experienced a poorly managed organizational change at some point, either as an offender or victim. We know from experience that when this happens, the individual changes that culminate in organizational change do not take place. We know that when the "people side of change" is mismanaged, projects don't realize the results and outcomes desired. We know that we have a lower likelihood of meeting objectives, finishing on time, and finishing on budget . And we know that speed of adoption will be slower, ultimate utilization will be lower, and proficiency will be lacking—all dragging down expected returns. 

Ignoring or mismanaging change manifests as costs and risks that play out on both the project level and organizational level. While some of these costs and risks may seem soft, many are quantifiable and can have a significant impact on financial performance for the project and the organization as a whole. 

Project-level costs and risks of mismanaged change

Project-level impacts relate directly to the specific project or initiative forgoing change management. These projects can impact tools, technologies, processes, reporting structures and job roles. They can result from strategic planning, internal stimuli such as performance issues, external stimuli such as regulation or competitive threats, or demands by customers and suppliers. The initiatives may be formalized as projects with project managers, budgets, schedules, etc., or they may be informal in nature but still impact how people do their jobs. 

While these projects can take on a number of different forms, the fact remains that ignoring or mismanaging the people side of change has real consequences for project performance:

• Project delays
• Missed milestones
• Budget overruns
• Rework required on design
• Loss of work by project team
• Resistance 
• Project put on hold
• Resources not made available
• Obstacles appear unexpectedly
• Project fails to deliver results
• Project is fully abandoned

When we apply change management effectively , we can prevent or avoid costs and mitigate risks tied to how individual employees adopt and utilize a change.

Organization-level costs and risks of mismanaged change

The organizational level is a step above the project-level impacts. These costs and risks are felt not only by the project team, but by the organization as a whole. Many of these impacts extend well beyond the lifecycle of a given project. When valuable employees leave the organization, the costs are extreme. A legacy of failed change presents a significant and ever-present backdrop that all future changes will encounter.

The organizational costs and risks of poorly managing change include:

• Productivity plunges (deep and sustained)
• Loss of valued employees
• Reduced quality of work
• Impact on customers
• Impact on suppliers
• Decline in morale
• Legacy of failed change
• Stress, confusion and fatigue
• Change saturation

Applying change management effectively on a particular project or initiative allows you to avoid organizational costs and risks that last well beyond the life of the project.

Costs and risks of failing to deliver results and outcomes

There is one final dimension of costs and risks to consider, beyond the project and organizational impacts. When we try to introduce a change without using effective change management, we are much less likely to implement the change and fully realize the expected results and outcomes. This final dimension provides answers to the question: What if the change is not fully implemented?

If the change does not deliver the results and outcomes—in large part because we ignored the people side of change —there are additional costs and risks.

Costs if the change is not fully implemented:

• Lost investment made in the project
• Lost opportunity to have invested in other projects

Risks if the change is not fully implemented:

• Expenses not reduced
• Efficiencies not gained
• Revenue not increased
• Market share not captured
• Waste not reduced
• Regulations not met

Change Risks and Change Management

Discussing the costs and risks of poorly managed change is yet another way to make the case for change management . Positioning change management as a cost avoidance technique or a risk mitigation tactic can be an effective approach for communicating change management's value or to get support for the resources you need for managing the people side of change.

Tim Creasey is Prosci’s Chief Innovation Officer and a globally recognized leader in Change Management. Their work forms the basis of the world's largest body of knowledge on managing the people side of change to deliver organizational results.

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7 Reasons Why Change Management Strategies Fail and How to Avoid Them

How are you influencing change in your organization? Learn to minimize disruption—and improve your chances of success—by avoiding these common missteps.

Mary Sharp Emerson

To stay competitive in today’s rapidly-changing business environment, organizations must be willing — and able — to constantly adapt and evolve their business strategy.

It sounds easy enough. After all, the COVID-19 pandemic is a perfect example of how quickly the world can change and how quickly businesses need to — and can — respond. 

The reality of change management is much less clear-cut. 

Organizations, like people, are often highly resistant to change, even when we know it’s necessary. As a result, successfully adopting a new strategy with a change initiative, regardless of how incremental or radical, is usually difficult and often messy. And the consequences of a poorly-managed organizational transformation can be devastating.

Today more than ever, organizations need leaders with the knowledge and skills to plan and manage change successfully. According to David A. Shore , instructor of two Harvard DCE Professional & Executive Development programs focused on strategies for leading change , leadership is often the key to a successful change initiative.

“When change initiatives fail (and they do so more often than not) they rarely fail on technical skills (hard skills), they fail on the people skills. I have identified what I have come to call ‘The Great Enablers.’  While they are not the goal of any change initiative, they are the engine and as such they represent a cornerstone of the programs I teach,” Shore notes.

Understanding some of the most common reasons why strategies for change fail — and ways to avoid those pitfalls — can help you prevent an organizational disaster and lead a successful change initiative.

What is Change Management and Why Do We Need It?

A change management strategy is a planned methodology that enables leaders to successfully guide an organization through change, while minimizing disruption and the risk of unexpected consequences. And while the goal may be to change the organization, the key to success — in most cases — lies in the ability to lead people through the change. 

Businesses seek to change — in most cases — because their current business strategy is no longer promoting the success of the organization. A new strategy is required to increase profit margins, for example, or remain competitive in a changing business landscape. 

“Change initiatives are the vehicles by which strategy is delivered,” according to Shore. “ They represent the most significant dimension in determining whether goals and objectives are achieved. They are the connective tissue that allows us to bridge the gap between strategy and execution .”

No change initiative looks the same, but will vary widely depending on the strategic goals of the organization. Your change initiative may focus on improving efficiency or performance or building better processes. It may be slow and iterative — introducing new features into an existing product, for instance — or it could be revolutionary, such as creating an entirely new product line. 

Yet regardless of the nature or scope of the change, it will likely be disruptive to your employees and to your business processes alike. Even small changes, no matter how well-meaning or necessary, can have unintended consequences. And as change becomes larger and more complex, the risks increase, as does the need for a systematic approach.

Therefore, having a systematic approach to change — and leading your teams through change — is critical.

As Shore notes, “A point of distinction between managing change and project management is that the former has as a cornerstone leading human capital (people) in a way that facilitates the intended outcome. If you can’t change your people, you can’t change anything.”

How Has Change Management Evolved?

The idea that changing business strategy must be managed is relatively new. Until the late 1940s (generally speaking), most leadership models were relatively straightforward: the boss decided to make a change and his subordinates carried it out.

Today, leaders are aware that change is extremely complex and that a heavy-handed, top-down approach is rarely successful. Thinking about how to manage change has moved from an academic exercise to the creation of actionable guidelines for business leaders.

From the 1950s to the early 1990s, the theory of change management — and it was very much a theoretical exercise at first — changed in two important ways. First, it began to identify the importance of the employee in promoting — and resisting — change. Second, it began to recognize that successful change often occurs in stages, and that these stages could be predicted, planned, and managed.

Change management as a formal, multi-phase process took its modern form in the late 1990s. Leading Change , a 1996 book by John Kotter, popularized the idea of change management, bringing it from academic theory into the practical world of business. Kotter’s eight-step change management process continues to define much of the language around change management nearly 25 years later. 

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7 Ways that Change Management Strategies Fail

Yet, even as thought leadership on change management has become more in-depth and sophisticated, one simple fact remains: change management is still very difficult. 

Successfully implementing change — whether large or small — remains one of the greatest challenges facing leaders. 

Identifying some of the most common reasons why change management strategies fail can help leaders think more critically about how their actions may be helping — or hindering — their organizations from reaching their goals. 

#1: Starting with an Incomplete or Poorly-Defined Strategy

When thinking about an organizational transformation, leaders often focus on what the change is and why it is necessary. However, failing to give equal priority to how the change will happen can undermine any transformation effort.  

Without a comprehensive change management strategy, short term tactical decisions can delay or undermine long-term results. They can lead your organization down an unexpected — or unwanted—path and make it more difficult, or even impossible, to achieve the desired results.

In addition, the lack of a strategic change management plan can make it more difficult to build a strong guiding coalition and buy-in, hinder your communication with employees, and create misunderstandings and diminish trust in the leadership team. 

The Solution: Invest significant time and energy into creating a comprehensive change management strategy before starting any change initiative. It can be helpful to choose a model to follow: Kotter’s 8-Step Process , Lewin’s Change Management Model , or Prosci’s ADKAR Ⓡ Model — to name a few — can all offer a starting point on which to build your unique strategy. 

As you build out your strategy, identify areas of resistance and potential problems you think you may encounter. SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis can be a helpful tactical tool to help develop alternate pathways to achieve your long-term goals. While you likely can’t plan for every single contingency, developing a robust strategy will help you minimize unexpected problems.

#2: Following a Strategy that is Too Rigid and Inflexible

Having a well-defined change management strategy can be key to keeping your change initiative on track. At the same time, however, being too dogmatic and inflexible in implementing that plan can be equally detrimental to your long-term success. 

No matter how much thought and planning you put into your strategy, you are unlikely to account for every development. Change — especially large-scale change — can take a long time, and the environment and market are also changing around you. Failure to adapt your strategy to unanticipated or sudden developments can render your long-term strategy ineffective, or at worst, irrelevant.

The Solution: Revisit your strategy plan frequently, both before and after unexpected developments occur. 

Be sure that your long-term vision and goals are clear, but also that your strategy includes short- and mid-term objectives that you can revisit and realign to account for changes in the environment around you. Don’t be afraid to make adjustments throughout the process to keep your end goals on track.    

#3: Lack of Effective Communications

Leaders often spend a great deal of time communicating about the proposed change in order to gain buy-in before beginning the change initiative. However, change management strategies often fail or fizzle out when leaders don’t communicate enough after the initiative is announced.

For example, you announce your vision and strategy for change in an all-staff meeting. You then reinforce the message in an email to the organization or the team. You schedule follow up meetings with key stakeholders and 1:1s with your employees. At this point, it’s easy to believe that the message has been received and the organization is on board. 

In reality, once the initial communication drive is over, the day-to-day demands of the job take over and enthusiasm for change diminishes. Your team quickly reverts to the comfort of the status quo.

The Solution: Create a short, comprehensible explanation of your change strategy. It should be clear, consistent, and constant. Be prepared to repeat that explanation frequently, throughout the entire process and with everyone who may be impacted, no matter how remotely. 

Make sure that every action that the leadership team takes aligns with your vision of change. Every interaction with your team, from a staff meeting to a performance evaluation, is an opportunity to educate the organization about why this change is important and the positive impact you believe it will have on the organization in the long run. 

When it comes to change management, remember that even if you think you have communicated enough, you probably haven’t. 

#4: Failing to Identify and Address Resistance

Every change initiative is going to encounter resistance. This is true no matter how much you worked to build a guiding coalition before launch and no matter how well you communicate and create enthusiasm after launch.

In fact, according to Shore, resistance to change is the most common reason why many change initiatives fail. 

“People are people—carbon and water. As such, we resist change. It’s important to recognize that managing change is about upsetting people only at a rate that they can tolerate. It’s all about physics. For change there must be movement. With movement there is friction,” Shore says. 

People resist change for many reasons. They may be uncomfortable with the unknown or perceived risk. They may misunderstand or disagree with the goals and/or the strategy of the change initiative. They may fear what change means for their role or even their job security. They may lack trust in the management team or the organization.

Unless their specific concerns are addressed, resistance can easily derail or undermine the change initiative, either covertly or overtly. As Shore notes, “The job of an agent of change is to address this friction.”

The Solution: Make a strategic and thoughtful assessment of how your change initiative may impact your employees in order to identify potential resistance from the start. Tailor your communication strategy so that you can address that resistance as soon as—or even before—it arises.

And most importantly, actively listen to and engage your employees throughout your change management strategy. Active listening is the best way to avoid misunderstandings, ensure that all parties have complete and accurate information, and address fear, anxiety, and discomfort that comes with any change.

#5: Disconnect Between Strategy and Culture

Have you heard your employees say, “That’s not the way we do things around here?” If you have, then your change management strategy is probably in conflict with your organizational culture.

Change initiatives that work against existing corporate culture will likely be more difficult and less likely to succeed. Demands to change workplace habits and behaviors will be met with distrust and resistance if employees lack trust that the organization will support and reward those changes in the long term. 

Conversely, if the proposed changes are already in line with a shared vision of the organization’s purpose and goals, employees are more likely to trust that their efforts in supporting change will be rewarded. 

The Solution: Ensure that your change management strategy is grounded in a realistic assessment of your organization’s culture and vision. 

Even before you begin a change, make certain that senior management and front line employees alike are aligned on organizational priorities and goals, as well as on reward structures and tolerance for risk. An effective communications plan should include a focus on how your change supports the shared vision for your organization.

#6: Setting Unrealistic Expectations

One of the major pitfalls when starting a change initiative is to push too hard, for too much, and too quickly. Rushing through a change increases the risk of mistakes and removes the opportunity to respond appropriately to changing events. And moving too fast can quickly burn out both your team and your organization. Change fatigue can quickly undermine even the most enthusiastic team.

The pressure to do too much too quickly comes in several different forms:

• The marketplace : Rapid change may be required to stay competitive. Waiting too long to launch a new product, for example, could leave an opening for your competitors.
• Top management : Executives often underestimate how long change takes and how much it will cost, and they overestimate the end results. Enthusiasm for change can quickly fizzle when it takes too long or gains aren’t perceived as “big enough.”
• The need for momentum : People and organizations alike have short attention spans. It can be challenging to sustain enthusiasm for change over the long term. 

The Solution: Managing expectations — both positive and negative — during a change initiative is just as important as managing the change itself. Remind yourself and your key stakeholders — frequently — that true change takes time. A well-paced solution is much more likely to be effective and successful. 

Be sure that your strategic plan is realistic in its goals and intended outcomes. Outline a clear timeline, with both short- and long-term objectives. Short- and mid-range goals will help your team stay on target without moving too quickly. 

#7: Not Creating—and Celebrating—Short Term Wins

Pushing for change too quickly can lead to burnout. Yet not showing positive progress in a timely manner can be equally detrimental. Employees and teams can easily lose momentum and enthusiasm for a change if they feel they aren’t making progress. 

And the more difficult the change is — the more it requires changing behaviors or making sacrifices — the more quickly your teams will lose interest.

The Solution: Don’t wait for wins to emerge naturally from the change management process. Build them into your strategic plan from the start. As you define your short- and mid-range goals, include achievable outcomes that will yield visible results. 

And when your team achieves those outcomes, be sure to publicize them as wins, and celebrate them — as soon as they happen. Building on the enthusiasm for a short term win will help sustain momentum for a longer duration. 

How Can I Learn to Avoid These Change Management Mistakes? 

Leading a change management strategy is challenging and takes effort and dedication. And even the most successful change leader is likely to make a few mistakes and missteps along the way.

However, the skills you need to improve your ability to manage change successfully can be learned at any point in your career. 

Professional development programs focused on business strategy generally — and change management strategy specifically — can give you the frameworks and tools to lead your organization’s change initiative to completion. These key leadership skills can help you advance your career and help your organization stay competitive in today’s crowded and chaotic marketplace.

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5 Critical Steps in the Change Management Process

• 19 Mar 2020

Businesses must constantly evolve and adapt to meet a variety of challenges—from changes in technology, to the rise of new competitors, to a shift in laws, regulations, or underlying economic trends. Failure to do so could lead to stagnation or, worse, failure.

Approximately 50 percent of all organizational change initiatives are unsuccessful, highlighting why knowing how to plan for, coordinate, and carry out change is a valuable skill for managers and business leaders alike.

Have you been tasked with managing a significant change initiative for your organization? Would you like to demonstrate that you’re capable of spearheading such an initiative the next time one arises? Here’s an overview of what change management is, the key steps in the process, and actions you can take to develop your managerial skills and become more effective in your role.

Access your free e-book today.

What is Change Management?

Organizational change refers broadly to the actions a business takes to change or adjust a significant component of its organization. This may include company culture, internal processes, underlying technology or infrastructure, corporate hierarchy, or another critical aspect.

Organizational change can be either adaptive or transformational:

• Adaptive changes are small, gradual, iterative changes that an organization undertakes to evolve its products, processes, workflows, and strategies over time. Hiring a new team member to address increased demand or implementing a new work-from-home policy to attract more qualified job applicants are both examples of adaptive changes.
• Transformational changes are larger in scale and scope and often signify a dramatic and, occasionally sudden, departure from the status quo. Launching a new product or business division, or deciding to expand internationally, are examples of transformational change.

Change management is the process of guiding organizational change to fruition, from the earliest stages of conception and preparation, through implementation and, finally, to resolution.

As a leader, it’s essential to understand the change management process to ensure your entire organization can navigate transitions smoothly. Doing so can determine the potential impact of any organizational changes and prepare your teams accordingly. When your team is prepared, you can ensure everyone is on the same page, create a safe environment, and engage the entire team toward a common goal.

Change processes have a set of starting conditions (point A) and a functional endpoint (point B). The process in between is dynamic and unfolds in stages. Here’s a summary of the key steps in the change management process.

Check out our video on the change management process below, and subscribe to our YouTube channel for more explainer content!

5 Steps in the Change Management Process

1. prepare the organization for change.

For an organization to successfully pursue and implement change, it must be prepared both logistically and culturally. Before delving into logistics, cultural preparation must first take place to achieve the best business outcome.

In the preparation phase, the manager is focused on helping employees recognize and understand the need for change. They raise awareness of the various challenges or problems facing the organization that are acting as forces of change and generating dissatisfaction with the status quo. Gaining this initial buy-in from employees who will help implement the change can remove friction and resistance later on.

2. Craft a Vision and Plan for Change

Once the organization is ready to embrace change, managers must develop a thorough, realistic, and strategic plan for bringing it about.

The plan should detail:

• Strategic goals: What goals does this change help the organization work toward?
• Key performance indicators: How will success be measured? What metrics need to be moved? What’s the baseline for how things currently stand?
• Project stakeholders and team: Who will oversee the task of implementing change? Who needs to sign off at each critical stage? Who will be responsible for implementation?
• Project scope: What discrete steps and actions will the project include? What falls outside of the project scope?

While it’s important to have a structured approach, the plan should also account for any unknowns or roadblocks that could arise during the implementation process and would require agility and flexibility to overcome.

3. Implement the Changes

After the plan has been created, all that remains is to follow the steps outlined within it to implement the required change. Whether that involves changes to the company’s structure, strategy, systems, processes, employee behaviors, or other aspects will depend on the specifics of the initiative.

During the implementation process, change managers must be focused on empowering their employees to take the necessary steps to achieve the goals of the initiative and celebrate any short-term wins. They should also do their best to anticipate roadblocks and prevent, remove, or mitigate them once identified. Repeated communication of the organization’s vision is critical throughout the implementation process to remind team members why change is being pursued.

4. Embed Changes Within Company Culture and Practices

Once the change initiative has been completed, change managers must prevent a reversion to the prior state or status quo. This is particularly important for organizational change related to business processes such as workflows, culture, and strategy formulation. Without an adequate plan, employees may backslide into the “old way” of doing things, particularly during the transitory period.

By embedding changes within the company’s culture and practices, it becomes more difficult for backsliding to occur. New organizational structures, controls, and reward systems should all be considered as tools to help change stick.

5. Review Progress and Analyze Results

Just because a change initiative is complete doesn’t mean it was successful. Conducting analysis and review, or a “project post mortem,” can help business leaders understand whether a change initiative was a success, failure, or mixed result. It can also offer valuable insights and lessons that can be leveraged in future change efforts.

Ask yourself questions like: Were project goals met? If yes, can this success be replicated elsewhere? If not, what went wrong?

The Key to Successful Change for Managers

While no two change initiatives are the same, they typically follow a similar process. To effectively manage change, managers and business leaders must thoroughly understand the steps involved.

Some other tips for managing organizational change include asking yourself questions like:

• Do you understand the forces making change necessary? Without this understanding, it can be difficult to effectively address the underlying causes that have necessitated change, hampering your ability to succeed.
• Do you have a plan? Without a detailed plan and defined strategy, it can be difficult to usher a change initiative through to completion.
• How will you communicate? Successful change management requires effective communication with both your team members and key stakeholders. Designing a communication strategy that acknowledges this reality is critical.
• Have you identified potential roadblocks? While it’s impossible to predict everything that might potentially go wrong with a project, taking the time to anticipate potential barriers and devise mitigation strategies before you get started is generally a good idea.

How to Lead Change Management Successfully

If you’ve been asked to lead a change initiative within your organization, or you’d like to position yourself to oversee such projects in the future, it’s critical to begin laying the groundwork for success by developing the skills that can equip you to do the job.

Completing an online management course can be an effective way of developing those skills and lead to several other benefits . When evaluating your options for training, seek a program that aligns with your personal and professional goals; for example, one that emphasizes organizational change.

Do you want to become a more effective leader and manager? Explore Leadership Principles , Management Essentials , and Organizational Leadership —three of our online leadership and management courses —to learn how you can take charge of your professional development and accelerate your career. Not sure which course is the right fit? Download our free flowchart .

This post was updated on August 8, 2023. It was originally published on March 19, 2020.

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• Published: 08 May 2024

A meta-analysis on global change drivers and the risk of infectious disease

• Michael B. Mahon   ORCID: orcid.org/0000-0002-9436-2998 1 , 2   na1 ,
• Alexandra Sack 1 , 3   na1 ,
• O. Alejandro Aleuy 1 ,
• Carly Barbera 1 ,
• Ethan Brown   ORCID: orcid.org/0000-0003-0827-4906 1 ,
• Heather Buelow   ORCID: orcid.org/0000-0003-3535-4151 1 ,
• David J. Civitello 4 ,
• Jeremy M. Cohen   ORCID: orcid.org/0000-0001-9611-9150 5 ,
• Luz A. de Wit   ORCID: orcid.org/0000-0002-3045-4017 1 ,
• Meghan Forstchen 1 , 3 ,
• Fletcher W. Halliday 6 ,
• Patrick Heffernan 1 ,
• Sarah A. Knutie 7 ,
• Alexis Korotasz 1 ,
• Joanna G. Larson   ORCID: orcid.org/0000-0002-1401-7837 1 ,
• Samantha L. Rumschlag   ORCID: orcid.org/0000-0003-3125-8402 1 , 2 ,
• Emily Selland   ORCID: orcid.org/0000-0002-4527-297X 1 , 3 ,
• Alexander Shepack 1 ,
• Nitin Vincent   ORCID: orcid.org/0000-0002-8593-1116 1 &
• Jason R. Rohr   ORCID: orcid.org/0000-0001-8285-4912 1 , 2 , 3   na1  

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• Infectious diseases

Anthropogenic change is contributing to the rise in emerging infectious diseases, which are significantly correlated with socioeconomic, environmental and ecological factors 1 . Studies have shown that infectious disease risk is modified by changes to biodiversity 2 , 3 , 4 , 5 , 6 , climate change 7 , 8 , 9 , 10 , 11 , chemical pollution 12 , 13 , 14 , landscape transformations 15 , 16 , 17 , 18 , 19 , 20 and species introductions 21 . However, it remains unclear which global change drivers most increase disease and under what contexts. Here we amassed a dataset from the literature that contains 2,938 observations of infectious disease responses to global change drivers across 1,497 host–parasite combinations, including plant, animal and human hosts. We found that biodiversity loss, chemical pollution, climate change and introduced species are associated with increases in disease-related end points or harm, whereas urbanization is associated with decreases in disease end points. Natural biodiversity gradients, deforestation and forest fragmentation are comparatively unimportant or idiosyncratic as drivers of disease. Overall, these results are consistent across human and non-human diseases. Nevertheless, context-dependent effects of the global change drivers on disease were found to be common. The findings uncovered by this meta-analysis should help target disease management and surveillance efforts towards global change drivers that increase disease. Specifically, reducing greenhouse gas emissions, managing ecosystem health, and preventing biological invasions and biodiversity loss could help to reduce the burden of plant, animal and human diseases, especially when coupled with improvements to social and economic determinants of health.

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Towards common ground in the biodiversity–disease debate

Biological invasions facilitate zoonotic disease emergences

Measuring the shape of the biodiversity-disease relationship across systems reveals new findings and key gaps

Data availability.

All the data for this Article have been deposited at Zenodo ( https://doi.org/10.5281/zenodo.8169979 ) 52 and GitHub ( https://github.com/mahonmb/GCDofDisease ) 53 .

Code availability

All the code for this Article has been deposited at Zenodo ( https://doi.org/10.5281/zenodo.8169979 ) 52 and GitHub ( https://github.com/mahonmb/GCDofDisease ) 53 . R markdown is provided in Supplementary Data 1 .

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Acknowledgements

We thank C. Mitchell for contributing data on enemy release; L. Albert and B. Shayhorn for assisting with data collection; J. Gurevitch, M. Lajeunesse and G. Stewart for providing comments on an earlier version of this manuscript; and C. Carlson and two anonymous reviewers for improving this paper. This research was supported by grants from the National Science Foundation (DEB-2109293, DEB-2017785, DEB-1518681, IOS-1754868), National Institutes of Health (R01TW010286) and US Department of Agriculture (2021-38420-34065) to J.R.R.; a US Geological Survey Powell grant to J.R.R. and S.L.R.; University of Connecticut Start-up funds to S.A.K.; grants from the National Science Foundation (IOS-1755002) and National Institutes of Health (R01 AI150774) to D.J.C.; and an Ambizione grant (PZ00P3_202027) from the Swiss National Science Foundation to F.W.H. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.

Author information

These authors contributed equally: Michael B. Mahon, Alexandra Sack, Jason R. Rohr

Authors and Affiliations

Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA

Michael B. Mahon, Alexandra Sack, O. Alejandro Aleuy, Carly Barbera, Ethan Brown, Heather Buelow, Luz A. de Wit, Meghan Forstchen, Patrick Heffernan, Alexis Korotasz, Joanna G. Larson, Samantha L. Rumschlag, Emily Selland, Alexander Shepack, Nitin Vincent & Jason R. Rohr

Environmental Change Initiative, University of Notre Dame, Notre Dame, IN, USA

Michael B. Mahon, Samantha L. Rumschlag & Jason R. Rohr

Eck Institute of Global Health, University of Notre Dame, Notre Dame, IN, USA

Alexandra Sack, Meghan Forstchen, Emily Selland & Jason R. Rohr

Department of Biology, Emory University, Atlanta, GA, USA

David J. Civitello

Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA

Jeremy M. Cohen

Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA

Fletcher W. Halliday

Department of Ecology and Evolutionary Biology, Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA

Sarah A. Knutie

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Contributions

J.R.R. conceptualized the study. All of the authors contributed to the methodology. All of the authors contributed to investigation. Visualization was performed by M.B.M. The initial study list and related information were compiled by D.J.C., J.M.C., F.W.H., S.A.K., S.L.R. and J.R.R. Data extraction was performed by M.B.M., A.S., O.A.A., C.B., E.B., H.B., L.A.d.W., M.F., P.H., A.K., J.G.L., E.S., A.S. and N.V. Data were checked for accuracy by M.B.M. and A.S. Analyses were performed by M.B.M. and J.R.R. Funding was acquired by D.J.C., J.R.R., S.A.K. and S.L.R. Project administration was done by J.R.R. J.R.R. supervised the study. J.R.R. and M.B.M. wrote the original draft. All of the authors reviewed and edited the manuscript. J.R.R. and M.B.M. responded to reviewers.

Corresponding author

Correspondence to Jason R. Rohr .

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Extended data figures and tables

Extended data fig. 1 prisma flowchart..

The PRISMA flow diagram of the search and selection of studies included in this meta-analysis. Note that 77 studies came from the Halliday et al. 3 database on biodiversity change.

Extended Data Fig. 2 Summary of the number of studies (A-F) and parasite taxa (G-L) in the infectious disease database across ecological contexts.

The contexts are global change driver ( A , G ), parasite taxa ( B , H ), host taxa ( C , I ), experimental venue ( D , J ), study habitat ( E , K ), and human parasite status ( F , L ).

Extended Data Fig. 3 Summary of the number of effect sizes (A-I), studies (J-R), and parasite taxa (S-a) in the infectious disease database for various parasite and host contexts.

Shown are parasite type ( A , J , S ), host thermy ( B , K , T ), vector status ( C , L , U ), vector-borne status ( D , M , V ), parasite transmission ( E , N , W ), free living stages ( F , O , X ), host (e.g. disease, host growth, host survival) or parasite (e.g. parasite abundance, prevalence, fecundity) endpoint ( G , P , Y ), micro- vs macroparasite ( H , Q , Z ), and zoonotic status ( I , R , a ).

Extended Data Fig. 4 The effects of global change drivers and subsequent subcategories on disease responses with Log Response Ratio instead of Hedge’s g.

Here, Log Response Ratio shows similar trends to that of Hedge’s g presented in the main text. The displayed points represent the mean predicted values (with 95% confidence intervals) from a meta-analytical model with separate random intercepts for study. Points that do not share letters are significantly different from one another (p < 0.05) based on a two-sided Tukey’s posthoc multiple comparison test with adjustment for multiple comparisons. See Table S 3 for pairwise comparison results. Effects of the five common global change drivers ( A ) have the same directionality, similar magnitude, and significance as those presented in Fig. 2 . Global change driver effects are significant when confidence intervals do not overlap with zero and explicitly tested with two-tailed t-test (indicated by asterisks; t 80.62  = 2.16, p = 0.034 for CP; t 71.42  = 2.10, p = 0.039 for CC; t 131.79  = −3.52, p < 0.001 for HLC; t 61.9  = 2.10, p = 0.040 for IS). The subcategories ( B ) also show similar patterns as those presented in Fig. 3 . Subcategories are significant when confidence intervals do not overlap with zero and were explicitly tested with two-tailed one sample t-test (t 30.52  = 2.17, p = 0.038 for CO 2 ; t 40.03  = 4.64, p < 0.001 for Enemy Release; t 47.45  = 2.18, p = 0.034 for Mean Temperature; t 110.81  = −4.05, p < 0.001 for Urbanization); all other subcategories have p > 0.20. Note that effect size and study numbers are lower here than in Figs. 3 and 4 , because log response ratios cannot be calculated for studies that provide coefficients (e.g., odds ratio) rather than raw data; as such, all observations within BC did not have associated RR values. Despite strong differences in sample size, patterns are consistent across effect sizes, and therefore, we can be confident that the results presented in the main text are not biased because of effect size selection.

Extended Data Fig. 5 Average standard errors of the effect sizes (A) and sample sizes per effect size (B) for each of the five global change drivers.

The displayed points represent the mean predicted values (with 95% confidence intervals) from the generalized linear mixed effects models with separate random intercepts for study (Gaussian distribution for standard error model, A ; Poisson distribution for sample size model, B ). Points that do not share letters are significantly different from one another (p < 0.05) based on a two-sided Tukey’s posthoc multiple comparison test with adjustment for multiple comparisons. Sample sizes (number of studies, n, and effect sizes, k) for each driver are as follows: n = 77, k = 392 for BC; n = 124, k = 364 for CP; n = 202, k = 380 for CC; n = 517, k = 1449 for HLC; n = 96, k = 355 for IS.

Extended Data Fig. 6 Forest plots of effect sizes, associated variances, and relative weights (A), Funnel plots (B), and Egger’s Test plots (C) for each of the five global change drivers and leave-one-out publication bias analyses (D).

In panel A , points are the individual effect sizes (Hedge’s G), error bars are standard errors of the effect size, and size of the points is the relative weight of the observation in the model, with larger points representing observations with higher weight in the model. Sample sizes are provided for each effect size in the meta-analytic database. Effect sizes were plotted in a random order. Egger’s tests indicated significant asymmetries (p < 0.05) in Biodiversity Change (worst asymmetry – likely not bias, just real effect of positive relationship between diversity and disease), Climate Change – (weak asymmetry, again likely not bias, climate change generally increases disease), and Introduced Species (relatively weak asymmetry – unclear whether this is a bias, may be driven by some outliers). No significant asymmetries (p > 0.05) were found in Chemical Pollution and Habitat Loss/Change, suggesting negligible publication bias in reported disease responses across these global change drivers ( B , C ). Egger’s test included publication year as moderator but found no significant relationship between Hedge’s g and publication year (p > 0.05) implying no temporal bias in effect size magnitude or direction. In panel D , the horizontal red lines denote the grand mean and SE of Hedge’s g and (g = 0.1009, SE = 0.0338). Grey points and error bars indicate the Hedge’s g and SEs, respectively, using the leave-one-out method (grand mean is recalculated after a given study is removed from dataset). While the removal of certain studies resulted in values that differed from the grand mean, all estimated Hedge’s g values fell well within the standard error of the grand mean. This sensitivity analysis indicates that our results were robust to the iterative exclusion of individual studies.

Extended Data Fig. 7 The effects of habitat loss/change on disease depend on parasite taxa and land use conversion contexts.

A) Enemy type influences the magnitude of the effect of urbanization on disease: helminths, protists, and arthropods were all negatively associated with urbanization, whereas viruses were non-significantly positively associated with urbanization. B) Reference (control) land use type influences the magnitude of the effect of urbanization on disease: disease was reduced in urban settings compared to rural and peri-urban settings, whereas there were no differences in disease along urbanization gradients or between urban and natural settings. C) The effect of forest fragmentation depends on whether a large/continuous habitat patch is compared to a small patch or whether disease it is measured along an increasing fragmentation gradient (Z = −2.828, p = 0.005). Conversely, the effect of deforestation on disease does not depend on whether the habitat has been destroyed and allowed to regrow (e.g., clearcutting, second growth forests, etc.) or whether it has been replaced with agriculture (e.g., row crop, agroforestry, livestock grazing; Z = 1.809, p = 0.0705). The displayed points represent the mean predicted values (with 95% confidence intervals) from a metafor model where the response variable was a Hedge’s g (representing the effect on an infectious disease endpoint relative to control), study was treated as a random effect, and the independent variables included enemy type (A), reference land use type (B), or land use conversion type (C). Data for (A) and (B) were only those studies that were within the “urbanization” subcategory; data for (C) were only those studies that were within the “deforestation” and “forest fragmentation” subcategories. Sample sizes (number of studies, n, and effect sizes, k) in (A) for each enemy are n = 48, k = 98 for Virus; n = 193, k = 343 for Protist; n = 159, k = 490 for Helminth; n = 10, k = 24 for Fungi; n = 103, k = 223 for Bacteria; and n = 30, k = 73 for Arthropod. Sample sizes in (B) for each reference land use type are n = 391, k = 1073 for Rural; n = 29, k = 74 for Peri-urban; n = 33, k = 83 for Natural; and n = 24, k = 58 for Urban Gradient. Sample sizes in (C) for each land use conversion type are n = 7, k = 47 for Continuous Gradient; n = 16, k = 44 for High/Low Fragmentation; n = 11, k = 27 for Clearcut/Regrowth; and n = 21, k = 43 for Agriculture.

Extended Data Fig. 8 The effects of common global change drivers on mean infectious disease responses in the literature depends on whether the endpoint is the host or parasite; whether the parasite is a vector, is vector-borne, has a complex or direct life cycle, or is a macroparasite; whether the host is an ectotherm or endotherm; or the venue and habitat in which the study was conducted.

A ) Parasite endpoints. B ) Vector-borne status. C ) Parasite transmission route. D ) Parasite size. E ) Venue. F ) Habitat. G ) Host thermy. H ) Parasite type (ecto- or endoparasite). See Table S 2 for number of studies and effect sizes across ecological contexts and global change drivers. See Table S 3 for pairwise comparison results. The displayed points represent the mean predicted values (with 95% confidence intervals) from a metafor model where the response variable was a Hedge’s g (representing the effect on an infectious disease endpoint relative to control), study was treated as a random effect, and the independent variables included the main effects and an interaction between global change driver and the focal independent variable (whether the endpoint measured was a host or parasite, whether the parasite is vector-borne, has a complex or direct life cycle, is a macroparasite, whether the study was conducted in the field or lab, habitat, the host is ectothermic, or the parasite is an ectoparasite).

Extended Data Fig. 9 The effects of five common global change drivers on mean infectious disease responses in the literature only occasionally depend on location, host taxon, and parasite taxon.

A ) Continent in which the field study occurred. Lack of replication in chemical pollution precluded us from including South America, Australia, and Africa in this analysis. B ) Host taxa. C ) Enemy taxa. See Table S 2 for number of studies and effect sizes across ecological contexts and global change drivers. See Table S 3 for pairwise comparison results. The displayed points represent the mean predicted values (with 95% confidence intervals) from a metafor model where the response variable was a Hedge’s g (representing the effect on an infectious disease endpoint relative to control), study was treated as a random effect, and the independent variables included the main effects and an interaction between global change driver and continent, host taxon, and enemy taxon.

Extended Data Fig. 10 The effects of human vs. non-human endpoints for the zoonotic disease subset of database and wild vs. domesticated animal endpoints for the non-human animal subset of database are consistent across global change drivers.

(A) Zoonotic disease responses measured on human hosts responded less positively (closer to zero when positive, further from zero when negative) than those measured on non-human (animal) hosts (Z = 2.306, p = 0.021). Note, IS studies were removed because of missing cells. (B) Disease responses measured on domestic animal hosts responded less positively (closer to zero when positive, further from zero when negative) than those measured on wild animal hosts (Z = 2.636, p = 0.008). These results were consistent across global change drivers (i.e., no significant interaction between endpoint and global change driver). As many of the global change drivers increase zoonotic parasites in non-human animals and all parasites in wild animals, this may suggest that anthropogenic change might increase the occurrence of parasite spillover from animals to humans and thus also pandemic risk. The displayed points represent the mean predicted values (with 95% confidence intervals) from a metafor model where the response variable was a Hedge’s g (representing the effect on an infectious disease endpoint relative to control), study was treated as a random effect, and the independent variable of global change driver and human/non-human hosts. Data for (A) were only those diseases that are considered “zoonotic”; data for (B) were only those endpoints that were measured on non-human animals. Sample sizes in (A) for zoonotic disease measured on human endpoints across global change drivers are n = 3, k = 17 for BC; n = 2, k = 6 for CP; n = 25, k = 39 for CC; and n = 175, k = 331 for HLC. Sample sizes in (A) for zoonotic disease measured on non-human endpoints across global change drivers are n = 25, k = 52 for BC; n = 2, k = 3 for CP; n = 18, k = 29 for CC; n = 126, k = 289 for HLC. Sample sizes in (B) for wild animal endpoints across global change drivers are n = 28, k = 69 for BC; n = 21, k = 44 for CP; n = 50, k = 89 for CC; n = 121, k = 360 for HLC; and n = 29, k = 45 for IS. Sample sizes in (B) for domesticated animal endpoints across global change drivers are n = 2, k = 4 for BC; n = 4, k = 11 for CP; n = 7, k = 20 for CC; n = 78, k = 197 for HLC; and n = 1, k = 2 for IS.

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Mahon, M.B., Sack, A., Aleuy, O.A. et al. A meta-analysis on global change drivers and the risk of infectious disease. Nature (2024). https://doi.org/10.1038/s41586-024-07380-6

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Article Contents

Introduction, three catastrophic fires in the past five years, wildland–urban interface risk and climate change, discussion and recommendations: improving wildfire risk reduction efforts, author contributions, data availability statement, wildfire risk management in the era of climate change.

Competing Interest: The authors declare no competing interest.

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Costas Emmanuel Synolakis, Georgios Marios Karagiannis, Wildfire risk management in the era of climate change, PNAS Nexus , Volume 3, Issue 5, May 2024, pgae151, https://doi.org/10.1093/pnasnexus/pgae151

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The August 8, 2023R Lahaina fire refocused attention on wildfires, public alerts, and emergency management. Wildfire risk is on the rise, precipitated through a combination of climate change, increased development in the wildland–urban interface (WUI), decades of unmitigated biomass accumulation in forests, and a long history of emphasis on fire suppression over hazard mitigation. Stemming the tide of wildfire death and destruction will involve bringing together diverse scientific disciplines into policy. Renewed emphasis is needed on emergency alerts and community evacuations. Land management strategies need to account for the impact of climate change and hazard mitigation on forest ecosystems. Here, we propose a long-term strategy consisting of integrating wildfire risk management in wider-scope forest land management policies and strategies, and we discuss new technologies and possible scientific breakthroughs.

Here, we draw from research on wildland–urban interface (WUI) fires from forestry and climate science to emergency management and economics, and we summarize the complexity and offer recommendations for policy making. Its significance stems from the analysis of emergency response in recent deadly fires, and our integrated approach which brings together multiple, diverse disciplines to explore policy-related, strategic, and operational approaches for addressing wildland fire risk in the era of climate change.

Wildland fires have existed since the beginning of history, with Paleontological evidence suggesting that early forest fires started to spread about 383 million years ago ( 1 ). As humanity evolved, forest fires were allowed to burn, depending on the objectives of human settlers ( 2 ). For example, even with the advent of fire suppression capabilities in the late 19th century, fire control efforts in the United States focused around settlements, and those beyond were left to burn unabated ( 3 ).

Despite impressive advances in forestry, fire science and firefighting technologies, and the leaps in wildland firefighting capabilities compared to 200 years ago, wildfire deaths are on the rise. The early February 2024 wildfires in Valparaiso, Chile killed over 130 persons and were the deadliest natural disaster in the country since the 2010 Mw∼8.8 earthquake and tsunami ( 4 ) and occurred in what has been called a “megadrought” ( 5 ). The August 8, 2023 Maui fires resulted in the highest death toll in the United States since the 1918 Cloquet and Moose Lake fires, and they amount to the fifth deadliest incident on record nationwide ( 6 ). It has been argued that at least some of these casualties might have been prevented had there been evacuation orders or emergency alerts ( 7 , 8 ). Less than two months after this catastrophe in Hawaii, the nationwide test of the Integrated Public Alert and Warning System established by the Federal Emergency Management Agency (FEMA), a state-of-the-art capability which has served as a model for countries around the world, came as a stark reminder of the complexity of wildfire risk.

The National Academies of Sciences, Engineering, and Medicine ( 9 ) point out that wildfire smoke can be transported over fairly long distances downwind and contaminate indoor and outdoor air, indoor surfaces, soil, and surface and even drinking water. Air pollution by plume transport is an insidious yet potent source of morbidity and mortality. In Europe alone, Kollanus et al. ( 10 ) estimated 1,080 premature deaths in 2008 from wildfire-originated fine particles in the atmosphere, with southern and eastern Europe disproportionately affected. The 2018 Camp Fire (Butte County, CA) resulted in PM 2.5 concentrations in downtown San Francisco, 240 miles away, peaking about six times higher than, and about double the US benchmark, for two weeks after the event ( 11 ). Chen et al. ( 12 ) found that fine particulate matter from wildfires was significantly associated with increased cardiovascular and respiratory mortality at a global level, and estimated the associated death toll at 33,000, or approximately 0.6% of all deaths in 749 cities in 43 countries and regions, in 2000–2016.

The devastation caused by many wildfires does not come without nontrivial societal and political ramifications. Communities affected by wildfires face the trauma of death, injury, loss of livelihoods, damage to homes, and psychological effects. Notwithstanding the provision of relief aid, more often than not, decision-makers face the outrage of their constituents for everything they didn’t do, for example, issuing alerts and evacuation orders. Electorates tend to punish incumbents for wildfire deaths and damage, so there is scapegoating and denial of responsibility by officials, which makes forensic analysis exceptionally difficult.

Wildfire risk lies in the confluence of climate change and development in the WUI. According to the NASEM ( 9 ) report, the WUI in the United States has expanded by 50% in the past 50 years, the fastest growing land use type, and another 10% increase is projected by 2030. Stemming the tide of wildfire death and destruction will involve bringing together diverse scientific disciplines into policy. Here, we will first review three fires to elucidate challenges posed, then we discuss how climate change is projected to increase fire activity, that is the frequency and intensity of fires. We will explore how governments are responding, and we argue that improvements in fire suppression capabilities, although required in the short term, may be financially unsustainable in the long run.

Lahaina, Maui, HI

On August 8, 2023, fires broke out in different parts of Maui, Hawaii. One of the fires destroyed the historic town of Lahaina and claimed 98 lives, becoming the deadliest US wildfire in more than a century.

Maui is no stranger to vegetation fires. However, on August 8, dry vegetation and strong descending winds climbed up to about 125 kilometers per hour and caused the fire to quickly spread out of control. Firefighting resources were stretched thin, responding to multiple incidents on the island. Lahaina was ravaged, and the majority of its about 1,800 buildings were completely burned. Some people sought refuge at sea, whereas others burned in their cars while trying to evacuate ( 7 , 8 ).

As fires broke out, broadcast emergency messages and social media posts from the County of Maui provided updates, alerts, and evacuation calls for some areas but apparently not Lahaina, a densely populated area with limited escape routes. Confusing messaging and delayed evacuation alerts (if they even took place) did not help.

Looking at milestones in the timeline, around 3:30 PM, a major road was closed just north of Lahaina because of what appeared then as just a flare-up of an earlier fire. Maui County's social media page didn’t announce the closure until 4:46 PM Evacuation orders for the entire area appear not to have been issued when the road was closed, or even soon thereafter. Maui officials claimed that text alerts were sent out, but that power and cellular disruptions prevented residents from receiving them. Some survivors have reported receiving no warning messages before the fire reached them, whereas at least one visitor reported receiving an emergency alert on their cellphone at 4:17 PM, 47 minutes after the road closure. Many local residents reported that they didn’t know the flames were approaching until the fire was nearby, and some said that they were informed by neighbors to evacuate. By 5:19 PM the fire had reached the waterfront in Lahaina, and by 5:33 PM people were seeking shelter in the water.

All this is quite surprising. Not only was there a fire in Maui in 2018 with similar problematic issues, but Hawaii has one of the most sophisticated tsunami warning systems in the world, fine-tuned since 1946, when a 17-meter tsunami hit the islands in the aftermath of the 1946 Aleutian tsunami ( 13 ), claiming 159 lives. Sirens are an integral part of the islands’ warning capabilities, yet local authorities defended their decision not to activate them in this fire. Mechanical sirens, as in Hawaii's All-Hazard Statewide Outdoor Warning Siren System produce a single tone, alerting people of an impending hazard, but provide no information about the nature of the hazard, its severity and, most importantly, protective action guidance. Note that the siren system is referred to as all-hazard, including wildfires, and claimed as the largest in the world.

To be effective, sirens need to be associated with a single clear protective action ( 14 ). In fact, Maui County had advised people that “[w]hen a siren tone is heard other than a scheduled test, tune into local Radio/TV/Cable stations for emergency information and instructions by official authorities. If you are in a low-lying area near the coastline; evacuate to high grounds, inland, or vertically to the 4th floor and higher of a concrete building”. In other words, Maui residents were given incomplete information—the reference to evacuating to high ground is likely for tsunami emergencies, yet there is no reference in the instructions to tsunamis. This confusing messaging is exactly what emergency managers are taught to avoid yet, in the aftermath, local authorities claimed they couldn’t have done anything differently.

A High Wind Watch issued on August 6 spoke of gale-force winds from the northeast on Maui until the night of August 8, as Hurricane Dora passed south of the Hawaiian Islands. It was upgraded to a High Wind Warning for Maui on August 7, with forecasts of gale-force winds from the east. Fire danger in Hawaii is weather-dominated, as vegetation grows rapidly with subtropical rainfall extremes, and dries rapidly during drought periods ( 15 ). On August 8, dry conditions on the island, strong easterly winds, and densely populated areas on the west coast of the island combined to create a dangerous situation. With hindsight, this combination may have fulfilled the criteria for issuing a warning of potential extreme fire behavior.

The Maui disaster triggered political backlash and legal battles. State and national levels came under scrutiny over their handling of the situation. The Maui County Emergency Management Administrator resigned in the weeks following the disaster. Three months following the fire, the Governor announced the creation of a $150 million recovery fund to help those who were injured in the fires or lost family members if they waive their right to file associated legal claims. The fund is initially paid for by the State of Hawaii, Maui County, Hawaiian Electric, and Kamehameha Schools, all of which have been named in legal actions over the wildfires.

Mati, Greece

Emergency and civil defense managers in Hawaii should have known better. Five years earlier, almost to the day, on July 23, 2018, a fairly small brush fire claimed 104 lives in Mati, Greece. Mati is a seaside community of about 5,000, approximately 30 km west of Athens, and a popular summer destination. On July 23, very strong winds descending from Mount Penteli at about 95 km/h (gusting to over 110 km/h) pushed the fire rapidly over dry vegetation, causing it to spread quickly, covering one-half mile in about half an hour from the nearest highway east of the town to the sea. In total, the fire took two hours to spread from where it started to the nearest beach—there is security camera video that captured the ignition. About 1,200 buildings were destroyed by the fire.

People were burned in their cars as they attempted to flee, while hundreds of people escaped to nearby seaside cliffs, hiked down to the beach, and were evacuated hours later from the water. A large number of firefighting resources had already been committed to a major incident about 80 km to the east, leaving limited resources available for the Mati fire.

In Mati, there was no warning, and people self-evacuated when flames were hundreds of feet away or did so at the encouragement of neighbors. Some police officers and firefighters reportedly went door-to-door to urge people to evacuate, but the lack of evacuation planning led to a series of traffic management failures, including, in one case, leading evacuees back toward the fire. The government and civil defense denied responsibility and claimed they couldn’t have done anything differently, even with hindsight ( 16 ). Despite the rapid spread of the fire, our calculations using agent-based evacuation models showed that, with a proper evacuation plan and public warning, the area could have been evacuated in time.

Unlike Maui, the legal and political fallout of the Mati disaster had historic proportions. At first, there were ad hominem attacks against scientists who spoke out about the lack of evacuation orders as contributing to the high death toll. This is also what happened in several countries in the first months of the COVID pandemic—governments were shooting the messengers. Eventually, however, the Alternate Minister for Citizen Protection, the Secretary General for Civil Protection, the Chief of the Hellenic Fire Service and the Chief of the Hellenic Police resigned. A series of negligence lawsuits were filed against the government by those who had lost loved ones and/or their homes. In addition, a four-year criminal investigation culminated with a trial which began on October 31, 2022, with twentyone senior elected and appointed officials facing felony charges. On April 29, 2024, six of the twentyone defendants were found guilty of negligent homicide. Some have argued that the handling of the aftermath of this fire led to the government losing national elections a year later.

The new government that took over rolled out the 112 Emergency Communications Service, following our relentless advocacy, editorials in major newspapers, and actual implementation work. The new service integrates a unified, multi-agency public safety answering capability, based on the European emergency number 1-1-2 with a nationwide, integrated public alert and warning system. This system is now used by the General Secretariat for Civil Protection (i.e. the country's national emergency management agency) to deliver effective life-saving information to the public. Alert messages are delivered primarily through cell phone SMS and additional communications pathways. In addition, new legislation voted in 2020 established an all-hazards planning approach, and municipalities are required to prepare a single emergency operations plan with hazard-specific and function-based annexes, as required. An evacuation annex is now mandatory.

The Maui and Mati fires bear eerie similarities. Dry vegetation and high winds, which pushed the fires downslope to densely populated areas with poor evacuation routes, and insufficient firefighting resources combined to cause both fires to quickly spread out of control. Preparedness failures, poor warning capabilities, and an apparent deficiency in evacuation planning led to the high death tolls. In both locales, people were burned in their cars, in Mati some because of a lack of evacuation planning that resulted in drivers being redirected back to the inferno, while in Lahaina possibly because of delays in evacuation and confusion with closed roads. In both cases, officials claimed that call centers were overwhelmed. Both events had political repercussions, and in both cases officials abdicated responsibility, claiming they wouldn’t have done anything differently even with hindsight.

WUI fires need not be so ghastly.

Rhodes, Greece

On July 18, 2023, a fire broke out on the Greek island of Rhodes. The fire was initially confined to the island's mountainous center, but spread to the south on the fourth day, fanned by strong, northerly seasonal winds. By July 23, the fire had reached the southern coast of the island, scorching more than 16,000 ha. With multiple fires burning simultaneously throughout the country, resources were stretched thin, despite the reinforcements sent by EU countries and the United States. The island is one of the most popular tourist destinations in the Mediterranean, exceeding 2 million visitors every year, and roughly the same size as Maui.

When it comes to evacuations, visitors are a vexing challenge, not least because of their limited proficiency in the host country's language, and their lack of familiarity with the area they are visiting. Yet, Greek authorities were able to evacuate over 20,000 local residents and tourists from the affected areas in Rhodes, within half a day, making it Greece's largest ever wildfire evacuation ( 17 , 18 ). The country's public alert and warning system was used to send multiple evacuation messages, as the fire approached residential areas. The slower overall rate of spread of the Rhodes fire may have allowed for the timely evacuation. However, the scale of the evacuation was considerable for Greece, and much more so for an island like Rhodes, and we that without a public warning system and a tried emergency management program, such as 112, the outcome would have been quite different. Ultimately, the fire devastated homes, hotels, and other businesses, yet the only casualty was the tragic loss of a volunteer firefighter. The efficacious crisis management in the aftermath bears noting, as most evacuees were sheltered in hotels or hosted by locals from night one. While at first tourist arrivals drastically fell, and hundreds of incoming flights were canceled, normalcy was restored within three weeks.

The wildland–urban interface challenge

More people living in WUI areas enhance ignition opportunities. Moritz et al. ( 19 ) identified several socioecological linkages and have focused on the impact to ecosystems by and their interdependencies with humans. While fires in remote areas are usually triggered by lightning storms, most wildfires appear to be human-caused ( 20 ). It is therefore hardly surprising that hot spots of fire activity have been identified in the WUI in the United States ( 21 ), and 95% of wildfires in Europe are reportedly caused by human negligence or arson ( 22 ). Radeloff et al. ( 23 ) state that the number of houses within wildfire perimentes thas doubled since the 1990s, due to both increased number of houses and larger burned areas. The number of wildfire-related deaths worldwide in the last four decades, based on the global EM-DAT database ( 24 ) shows that 10% of the fires appear responsible for 78% of the deaths (Figure 1 ). Furthermore, the single deadliest fire each year was responsible for 65% of all the deaths in that year, on average. In other words, a small number of fires produce the vast majority of deaths, while eight out of the ten deadliest fires occurred in the WUI.

Wildfire deaths per year, 1970–2023 ( 24 ).

Fires in the WUI pose unique challenges to fire suppression and emergency response. First, whereas urban and wildland firefighting tactics are fundamentally different, WUI fire suppression inherently involves both in close proximity, and tactical incompatibilities may appear. Urban fires will typically have multiple exposures with a fixed source, and direct fire attack using water or foam is the norm. On the other hand, wildland firefighting techniques very often involve indirect attack ( 25 , 26 ). For example, a fireline may be used to interrupt fuel continuity or a backfire may be employed to deprive the fire of oxygen. In the WUI, exposure usually involves a long flame front and multiple sources of ignition. In WUI fires, structural firefighters operate in close proximity with their wildland counterparts, which often creates challenges in communications and coordination, especially when they come from different organizations and jurisdictions.

Different firefighting tactics also mean different equipment. Wildland firefighting personal protective equipment is lighter because structural and atmospheric hazards are more limited in the open, and mobility is essential ( 26 ). Wildland firefighting engines are typically smaller and carry less equipment to remain mobile. This essential mobility in the wilderness may become a limiting factor, and possibly a source of danger, to firefighters in the WUI.

In addition, delayed fire reporting or increased response times increase fire risk to isolated homes and other structures ( 27 ). Fireline access can be challenging, as small backcountry roads and covered bridges might constrain anything but the smallest fire engines, and mutual aid resources could find navigating poorly charted rural roads a hindrance. Also, water supply may be scarce because of a lack of fire hydrants or failures during a power outage ( 28 ). This was the case in Lahaina, in both 2018 and 2023 and in the 2024 Viña del Mar fires in Chile, which took place while this paper was under review.

Second, evacuations are often required in WUI fires but are substantially different than organized evacuations implemented before river floods, landslides, and other natural hazards, or following accidents involving hazardous materials. Wildfire evacuations usually are decided and implemented on very short notice, notably because of difficulties in forecasting weather and predicting fire behavior. In Australia, in particular, there was debate about “stay and defend or go”, but the discussion seems to have settled in favor of “go” ( 29 ). Emergency planning helps alleviate some of that uncertainty. A small number of evacuation courses of action may be analyzed and included in emergency plans, offering options depending on the relative position of residential areas and the fire perimeter, as well as the current and projected weather, topography, and fuels. In Portugal, for example, predesigned evacuation routes and shelter locations are communicated to the public before disaster strikes, thus reducing clearance times when evacuations are warranted ( 30 ).

Regardless, many WUI areas have poor evacuee egress options, not only because of narrow, winding roads, but also traffic congestion ( 31 ). For instance, 23 people, including three seasonal firefighters, were trapped and perished while evacuating the village of Artemida, Greece during the 2007 fire south of ancient Olympia ( 32 ), over a narrow backcountry road that was the only option ( 33 ). In the 2018 Camp Fire in Northern California, staff evacuated patients from the local hospital in their own vehicles. On one occasion, the drive to safety out of the heavily wooded area allegedly took about three hours. This was a very difficult terrain for timely evacuations, nonetheless over 40,000 managed to evacuate. Alerts were reportedly not received by at least 50% of the residents, but completely without them the death toll would likely have been much higher than the 84 who perished. In another example, serious traffic congestion ensued when residents in West Kelowna, British Columbia were asked to evacuate during the 2015 Munt Law wildfire ( 34 ).

With this inadvertently rapid operational tempo, reducing the time between decision-making and the actual evacuation by providing people advanced notice is paramount. Mati and Maui and, to a lesser extent, Paradise—all three incidents were haunted by the lack or failure of public alert and warning systems ( 35 ).

Third, wildfires can rapidly spread out of control and increase in complexity. Large fires are among the most complex incidents, not least because of the geographic area involved, the large number of resources involved, organizational complexity, jurisdictional boundaries, weather, and difficulty in predicting fire spread ( 36–39 ). WUI fires add more layers of complexity, due to the threat to life, property and critical infrastructures, as well as political sensitivities. For example, it has been reported that, during the Mati fires, politicians were calling the fire department asking for prioritization of resources to favor friends and relatives. Climate change is one of the factors increasing the potential for extreme fire behavior, therefore making firefighting less routine while making fires themselves more routine.

Fourth, wildland fires are intricately related to critical infrastructure and form complex feedback loops which lead to compound events ( 40 , 41 ). The risk to energy production and generation assets and the power grid increases with wildfire incidence. Power lines can ignite wildfires through a variety of mechanisms, and fires can damage power utility assets, causing widespread power outages ( 42 ). California's largest utility, Pacific Gas and Electric, pleaded guilty to manslaughter charges and filed for bankruptcy in early 2019, accepting responsibility for its downed power lines that triggered the 2018 Camp Fire, allegedly the costliest natural disaster in that year worldwide. Hawaiian Electric is currently facing lawsuits for alleged negligence in the Maui fires. On the other end, in Mati, the country's national electricity corporation steadfastly refused to entertain even the suggestion that one of its power lines near the point of ignition may have triggered the fire, and thus far has gotten away with it.

The cascading effects of wildland fires increase agent-generated demands and complicate response-generated demands ( 40 , 43 ). Almost any critical infrastructure asset may be affected by wildland fires, even water treatment plants. Fires can melt underground water pipes, thus affecting firefighting, and they can destroy communication towers and power substations. Operators then need to find workarounds or make temporary repairs to restore service to priority customers, typically other critical infrastructure systems. At the same time, governments need to work with operators and affected critical customers to provide backup solutions. A vicious circle ensues, as infrastructure damage delays response and short-term recovery efforts, which in turn slow down restoration and repair ( 44 ).

Climate change and wildfire risk

Wildland fires have an intricate relationship with climate change. Bowman et al. ( 45 ) estimated that wildland fires are responsible for 19% of the anthropogenic radiative forcing. Climate change does yield higher temperatures and drier conditions that prime the landscape for fires to catch and spread more easily. Flannigan et al. ( 46 ) estimate that fire seasons will last 20 days per year longer in the northern high latitudes by the end of the century. The IPCC Sixth Assessment Report ( 47 ) notes that fire weather is expected to increase in many parts of the world and, a 2-degree global warming scenario is projected to increase burned area globally by 35%. These estimates are corroborated by regional studies, which point to an increase in the number of human-induced wildfires, burned area, and wildfire risk ( 21 , 48–56 ).

These scenarios are hardly fictitious, as climate change is already increasing wildfire risk around the world. Fire-prone areas are extending poleward to areas previously unaffected. Jolly et al. (2015) found that, by 2013, fire seasons had lengthened in about one-quarter of the Earth's vegetated surface, resulting in an increase of the global average fire season length by 18.7%, compared to 1979. They also estimated that, between 1979 and 2013, the burnable area affected by longer fire weather seasons had doubled. Furthermore, the frequency of long fire-weather seasons increased across more than half of the global vegetated area between 1996 and 2013, compared with 1979–1996. Regional studies corroborate these global findings by showing an increase in the number of fires and the burned area during fire seasons, as well as in the size, extent, and frequency of large fires ( 49 , 56–61 ). Consensus is emerging that the conventional suppression-centered wildfire and forest management strategies applied so far no longer efficiently address megafires, variously defined, but usually as fires that burn over 40,000 hectares.

Furthermore, overnight burning events (OBE), defined as fires that burn through the night, have recently been changing what used to be a familiar diurnal fire cycle. Luo et al. ( 62 ) found that 20% of the 1084 fires burning over 1000 hectares in the period 2017–2020 were OBEs, peaked in the summer, and were primarily associated with droughts. Balch et al. ( 50 ) claimed that, worldwide over the past 30 years, flammable nights have increased by seven, across all burnable lands, and found that night fires are about 7% more intense, while the vapor pressure deficit has increased by 25%. For the western United States, they estimated an 11-day increase over the same period. There is little doubt that there has been an acceleration of OBEs.

Figure 2 depicts megafires between 2012 and 2022 in Europe, Canada, and the United States, compiled out of three different datasets. The European Forest Fire Information System is operated by the European Commission Joint Research Center. Burned areas are estimated from satellite imagery, and information was available until 2023. Natural Resources Canada maintains the Canadian Wildland Fire Information System, based on a compilation of information provided by Canadian fire management agencies including provinces, territories, and Parks Canada. At the time of this writing, data was available only until 2021. In the United States, the National Interagency Fire Center Open Data Site provides a wealth of wildfire-related geospatial information. This dataset includes wildland fires reported to the Integrated Reporting of Wildland Fire Information incident service until 2023.

Megafires in Europe ( 63 ), Canada ( 64 ) and the United States ( 65 ) between 2012 and 2022.

One conclusion from the map in Figure 2 is the lack of a unified system for reporting wildfires around the world. Wildfire data collection around the world is a highly localized endeavor. Data collection techniques vary widely, from the compilation of reports from fire services to highly sophisticated uses of satellite imagery. Although most G20 countries publish quasi-regularly annual wildfire statistics in their official languages, data on individual fires is generally scarce. To make matters worse, there is hardly any consistency in either content or the granularity of the information reported across countries.

Finally, although the short- and long-term effects of wildfires on forests vary with the ability of tree species to regenerate after fires, both the size and costs of wildland fire suppression operations are growing. The increase in cost is partially driven by the high cost of protecting property in the WUI, and urbanization will drive costs even higher. Wildfire suppression costs in the United States have increased fourfold from 1985 to 2016 ( 21 ).

Wading into uncharted waters, governments have mobilized funding for improving suppression capabilities, with aerial firefighting absorbing the lion's share. Improvements in preparedness tend to follow particularly destructive fires or very active fire seasons. For example, following an increase in wildfire incidence across EU countries, the European Commission established “rescEU”, for procuring fixed and rotary wing firefighting aircraft, to create a last-resort capability buffer. Thus, rescEU's aerial firefighting fleet was doubled in 2023, reaching 28 aircraft in 2023, with 12 additional aircraft on order ( 66 , 67 ).

Greece has relied on a combined aerial firefighting fleet of nationally owned and leased aircraft. The country found itself in a double predicament, facing increasingly devastating fire seasons, just as it was getting out of a deep financial crisis, which had essentially prevented the acquisition of expensive assets. It has been progressively leasing more firefighting helicopters and airplanes. Following a series of devastating fire seasons, in 2020, the government announced “Aegis”, a behemoth two-billion-euro program, a third of which will serve to essentially double the country's aerial fighting fleet. In 2022, the Hellenic Fire Service also instituted helitack crews, that is, teams of firefighters transported by helicopter to poorly accessible wildfire flare ups.

France faced a particularly active season in 2022. The total burnt area was 72,000 hectares, or almost five times that of 2021 and about three times that of 2017. Preparing for 2023, it added nine additional fixed and rotary wing aircraft to its 38. It also increased the number of wildland fire-engine strike teams from 44 in 2022 to 51 in 2023 ( 68 ). According to the US Congressional Budget Office ( 69 ), the federal government spent $17.5 billion on wildfire suppression and disaster assistance between 2016 and 2020. In California, following expanding fire seasons and a series of devastating fires, the Department of Forestry and Fire Protection recently acquired 12 new firefighting helicopters and is planning to add seven air tankers to its fleet ( 70 ).

On the other hand, wildfire mitigation and prevention have traditionally received less attention and funding. For instance, the Greek Forest Service had been understaffed, and activities poorly coordinated and underfunded, for decades ( 71 ). Feo et al. ( 72 ) noted a “long history of underinvestment in prevention and mitigation” in California. These are examples of how voters often reward politicians for delivering disaster relief, but not for investing in preparedness, and even less so for mitigation and adaptation, hence governments underinvest ( 73 ).

Moritz et al. ( 19 ) have argued that “cultural and institutional systems affect public response to wildfire, as do psychological and social dynamics”. While true overall, the death toll in recent WUI fires suggests the public is inching towards favoring evacuation. Recent research suggests that public education can motivate voter support in favor of mitigation and preparedness ( 74 ). Anecdotal wildfire policy examples suggest that climate change education in the last few years may have helped to sway public opinion in favor of wildfire mitigation. For instance, in preparation for the 2022 fire season, the Greek government spent 72 million euros, equivalent to the cost of two medium-sized firefighting airplanes, in two nationwide wildfire hazard mitigation programs, involving (i) fuel reduction and clearing and (ii) forest thinning; such an investment was unthinkable five years earlier. It also reorganized the Forest Service to improve coordination and funding. In 2020 and 2021, the State of California appropriated $2.7 billion over a four-year period to wildfire prevention and mitigation, a number which dwarfs the Federal Government's $4 billion through the Infrastructure Investment and Jobs Act and the Inflation Reduction Act ( 75 ).

With rising fire activity brought on by climate change and human development, and increased exposure of people and property in WUI areas, it is unlikely that today's suppression-focused paradigm will remain sustainable, possibly not even in the near future. Here, we present a new paradigm in wildfire risk management that goes beyond suppression and even mitigation, by integrating science-based land management.

First, in light of the projected increase in fire activity and decades of unmitigated biomass accumulation in forests around the world, maintaining adequate fire suppression capabilities, even through mutual aid agreements, may no longer be a fiscally responsible option. On the other hand, the cost-to-benefit ratios of wildfire hazard mitigation measures, including retrofitting buildings to meet or exceed building code standards, range from ¼ to ½ ( 76 ). Communities should consider mitigation strategies that have worked for other hazards, such as insurance and drastically limiting development in the WUI. Fuel treatment strategies, such as prescribed burning, fuel reduction and clearing, and forest thinning, have all shown potential in mitigating wildland fire risk ( 2 , 77 ). In addition, retrofitting properties in the WUI to resist fire hazards has paid off time and again ( 78 ). For instance, a photograph of a 100-year-old wooden house in Lahaina became viral in the aftermath of the August 8 fire, as it was left unscathed while surrounded by piles of charred debris (Figure 3 ). It was later revealed that the owners had retrofitted the home to mitigate wildfire risk. Furthermore, learning from indigenous fire stewardship practices can help mitigate wildfires and increase biodiversity ( 79 ).

Red-roofed Lahaina home left unscathed by the August 8 fire (Source: Getty Images).

Nevertheless, even with increased investment, implementing hazard mitigation strategies and developing additional capabilities will take time. Therefore, improving wildfire response is still needed. Given resource constraints, communities will likely have to prioritize the development of both suppression and mitigation capabilities by accounting for the effects of climate change on forest ecosystems. Multi-year, integrated wildfire risk management plans extending beyond electoral cycles can help reduce the sensitivity of risk management to shifting political short-term priorities and ensure sustainable strategies. Governments need to avoid the established pitfalls of short-sighted, political decision-making and policy choices shaped by what just happened instead of planning for future expectations ( 80 ).

Second, the growing number of megafires indicates that land management strategies need to account for the impact of climate change on forest ecosystems, as well as local effects, such as the rate at which biomass re-accumulates. Governments need to work closer with the forest products industry to integrate land management and wildfire risk management policies. Heterogeneity in vegetation type, age, and structure can help ecosystem resilience to climate change and reduction of biodiversity loss. Fire hazard mitigation measures can be adapted to deliver the needed heterogeneity, for example, by diversifying the conditions of prescribed burns ( 19 ). Moreover, novel uses of wood products and creating markets for excess biomass and smallwood removal and utilization can create local economic development opportunities, while increasing the ecosystem's resilience to wildfires. Several funding mechanisms are now being considered to support appropriate public/private partnerships. Examples include green bonds and more complex schemes, such as partial subsidization of economic opportunities, contingent on the implementation of wildfire mitigation or post-wildfire restoration measures, including landslide and flood mitigation.

Third, in terms of crisis management, a fundamental shift is needed from a mindset of fire suppression to one of emergency response. The increased exposure of people reinforces the need for community-based evacuation planning. Evacuation plans identify transportation routes and ways to increase evacuation throughput (such as contraflow), transportation modes, including mass transit, and shelter locations, so that emergency managers know how little time they have to issue evacuation orders. It is thus clear that public alert and warning systems are becoming an increasingly critical link in the process. These systems provide emergency information to the public, and save lives when disasters are about to strike. Early disaster research ( 81 , 82 ) highlighted that to be effective warning messages need to be received from multiple communication pathways and issued from credible sources. Modern public alert and warning systems enable emergency management agencies to disseminate information through multiple pathways, including mobile and landline phones, radio, television, highway variable-message signs and others. The combination of evacuation plans, public education before disaster strikes, and public alert and warning systems can create a powerful defense against wildland fires and can reduce the loss of life.

Because of the inherent complexity in combining all those technologies, these systems should be tested to the limit of their abilities at regular intervals. In addition to the obvious maintenance benefit, these tests are opportunities for informing the public about the capabilities of alert and warning systems, as well teaching individual and family self-protection in disasters. In the United States, nationwide tests of the Emergency Alert System (which is based on radio and television, cable systems, and satellite radio and television) and the Wireless Emergency Alert (WEA) system, (which delivers alerts from cellular towers to mobile devices using a one-to-many technology called Cell Broadcast (CB)), they have been required no less than every three years since 2015. Nonetheless, the third nationwide test on October 4, 2023 (Figure 4 , left), which came after the Maui catastrophe ( 83 ), was treated by the major news media everywhere as if it was the first ever. In one way it was, because people paid attention to it and could not have opted out, as was the case with the second test message. For the record, the first test was conducted on October 3, 2018, using the Presidential Alert classification and the second on August 11, 2021, using the State/Local WEA Test classification, which requires users to opt in to receive the test alert.

Screenshots of the 2023 nationwide WEA test in the United States (left) and the first nationwide Cell Broadcast message ever in Greece, in 2020 (right). An estimated 300 national messages have followed since then this 11 March 2020 first CB message.

As of December 2018, and likely following the realization that lives could have been saved in the Mati fires earlier that year had there been warnings, European Union countries have been legally required to put in place public alert and warning systems using location-based SMS, or similar technologies, no later than June 2022. However, there are no testing requirements. Although such systems were already used in several European countries before that deadline, Greece was one of the first countries to use Cell Broadcast for wildfire evacuations. Tests are not legally required in Greece as in the United States, but its first nationwide alert was sent on March 11, 2020 (Figure 4 , right), in response to mounting cases of COVID-19, and served as a demonstration of the capability.

Warning and evacuation processes also need to account for populations with access and functional needs. Effective systems can alert populations with disabilities or other special needs, include those with limited proficiency in the main language(s) used in alert and warning messages and, ultimately, anyone who may have difficulties obtaining alert and warning SMS and information.

A combination of forward and reverse planning is required to prepare such plans ( 84 , 85 ). Forward planning builds the evacuation process by describing potential decisions and actions sequentially. Plans should address both agent-generated demands (for example, transportation and shelter) and response-generated demands (for example, information management and logistics). Then, reverse planning determines the time required to complete each task, given the resources that can realistically be made available. Working backwards and using time estimates and task dependencies, emergency managers can identify the times required to complete evacuations once the decision is made. The combination of forward and reverse planning informs the development of time or land-benchmark triggers for evacuation decision-making. For example, there will be evacuations regardless of conditions, if a fire reaches a particular critical location, or if there is less than x minutes for the fire to spread from its point of ignition to the nearest shoreline.

Fundamentally, hard as it may be in practice, evacuations need to be completed before the flame front spreads close enough to populated areas. Fire smoke may cause serious injury to sensitive individuals; this needs to be accounted for as well. Evacuation modeling is necessary to inform evacuation planning and decision-making. It can provide estimates of the time needed to evacuate areas threatened by wildfires, as well as pedestrian and vehicle traffic flow rates, in different scenarios and allows analysis of different courses of action ( 86 , 87 ). As was done post-facto in Mati ( 88 , 89 ), combined with wildfire spread simulation, evacuation modeling can be a powerful tool in setting triggers for evacuation decision-making ( 90 ). Stefanakis et al. ( 91 ) used an AI statistical model of a tsunami “experiment” constantly updated as new results arrived, then future query points were selected according to the objectives, until achieved. In this manner, they identified worst-case scenarios that were previously only obvious with 100% hindsight. Such active experimental design and machine learning algorithms can reduce the exceptionally large number of numerical simulations needed to identify time-optimal escape routes in advance, particularly in the presence of projectiles (embers), which change the spread dynamics. Evacuation modeling is also a powerful tool in public outreach, as people at risk can expect how much time they really have. Coupled with avatars, people can visualize themselves evacuating, at different speeds, temperatures, and visibilities. Such an approach could become the gold standard for planning evacuations and educating people.

Fourth, science and technology can be leveraged to improve strategic, operational, and tactical emergency planning. Evaluating variables, such as meteorological conditions, fire danger, fire location, time of day, and fire size at the time of dispatch are now increasingly used in setting dispatch levels and resource estimates, along with lessons learned from previous fires and institutional memory. Machine learning, again, can streamline these processes. For example, Lam et al. ( 92 ) show how it can best medium-range numerical weather predictions (NWP) forecasts very quickly. Introducing AI fire prediction operationally remains vexing, given the varied locations, diverse data, and one-of-a-kind fires, even in a single locale.

Even when such timely predictions materialize, resource management should become more dynamic and anticipatory through the employment of other tools. For instance, mutual aid agreements can be activated preemptively based on risk estimates. In 2023, Greece activated the EU Civil Protection Mechanism (the European equivalent to the Emergency Management Assistance Compact in the United States) to preposition fire engines and hand crews from other countries in high-risk areas, during the hottest and driest summer months. The Hellenic Fire Service hires seasonal firefighters every year, aiming to increase its force by 10% during the “hot” season ( 8 ). These actions are particularly useful in islands, which present additional tactical challenges, not the least of which is related to their insularity and limited options for evacuation. Emergency management worldwide needs to consider the option of evacuating to beaches, which has made fires on Greek islands far less deadly than the mainland.

Earlier, we discussed how advances in forestry and biology can support integrated management of wildfire risk, how cutting-edge communications systems enable alert and warning messages to reach millions of people in seconds, and how evacuation modeling can support emergency planning and rapid decision-making.

Satellite images are a staple in many crisis management centers. Landsat has been around for decades, but the time windows between images do not allow for effective proactive modeling. Algorithms convert observations of the Earth's surface in the visible and infrared domains from meteorological and other satellites into measurements of fire hot spots and assessments of wildfire impacts in near real-time ( 93–95 ). Recently, advances in earth observation have allowed scientists, at least in Europe and North America, to track wildfires and even calculate fire spread, every twelve hours, based on satellite imagery ( 96 ). NASA's Fire Events Data Suite is claimed to provide more frequent monitoring of fire activity, growth, and behavior than has ever been available ( 59 ). In a significant breakthrough, private operating satellite constellations now claim they are able to provide end users with predictions of the spread of wildfires and floods, informed through data assimilation, as images become available from successive satellite passes. In one example, a satellite constellation of Portugal and Spain, possibly to be augmented by Greek satellites, beginning (it's been claimed) in 2024, will provide high resolution synthetic aperture radar (SAR) images about every four hours. The consortium will also provide estimates of the projected evolution of the fire perimeter, until the next set of images becomes available. When augmented by thermal imaging and comprehensive vegetation spatial distributions, the evolution predictions can improve further and can become game changers in megafire suppression. Once such analyses become standard, AI fire modeling could become routine, given that there will be uniform image datasets associated with specific weather parameters to mine from.

Moreover, artificial intelligence is already in use to streamline real-time or near real-time detection of wildfires in poorly accessible areas ( 97 , 98 ). State-of-the-art robots provide situational awareness, and autonomous systems operating closer to the fireline are under development for improving information management ( 99 ). The integration of satellite imagery with feeds from other sources, such as thermal, surveillance and traffic cameras and weather stations, they can vastly accelerate information management in the Emergency Operations Centers of the next decade.

Climate change, increased development in the WUI, and a long history of emphasis on fire suppression over hazard mitigation has increased wildfire risk worldwide. Governments are exploring the issue, but spending is mostly geared toward fire suppression. Here, we propose a long-term approach, incorporating wildfire risk management in wider-scope forest land management policies and strategies. The latter need to account for the impact of climate change and hazard mitigation on forest ecosystems. Improving suppression capabilities is like performing CPR on a cardiac arrest patient: it buys needed time until a more sustainable strategy takes effect, but will not, in and by itself, suffice for longevity. A renewed focus and increased spending on hazard mitigation and fire prevention is also required to stem the impact of megafires threatening human settlements and ecosystems in the WUI. Furthermore, a fundamental shift is needed from a mindset of fire suppression to one of emergency response. Evacuation planning supported by public alert and warning capabilities always saves lives, and more so with prior planning. Last, we urge the wildland fire community to invest in the uptake of scientific breakthroughs and new technologies, including machine learning and earth observation, to help improve decision-making and, ultimately, save more lives. Until then, in at-risk WUI areas, everyone needs to understand that a threatening wildfire could happen anytime from spring to fall and that they may need to leave immediately.

The authors declare no funding.

Both authors designed and performed research, analyzed the data, and wrote the paper.

The following data were used in the preparation of this manuscript:

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Biodiversity Loss Increases the Risk of Disease Outbreaks, Analysis Suggests

Researchers found that human-caused environmental changes are driving the severity and prevalence of disease, putting people, animals and plants at risk

Christian Thorsberg

Daily Correspondent

Human-driven changes to the planet are bringing widespread and sometimes surprising effects—including shifting the Earth’s rotation , hiding meteorites in Antarctic ice and, potentially, supporting locust swarms .

Now, a large-scale analysis of nearly 1,000 scientific studies has shown just how closely human activity is tied to public health. Published last week in the journal Nature ,   the findings suggest anthropogenic environmental changes are making the risk of infectious disease outbreaks all the more likely.

The biodiversity crisis—which has left some one million plant and animal species at risk of extinction —is a leading driver of disease spread, the researchers found.

“It could mean that by modifying the environment, we increase the risks of future pandemics,” Jason Rohr , a co-author of the study and a biologist at the University of Notre Dame, tells the Washington Post ’s Scott Dance.

The analysis centered on earlier studies that investigated at least one of five “global change drivers” affecting wildlife and landscapes on Earth: biodiversity change, climate change, habitat change or loss, chemical pollution and the introduction of non-native species to new areas. Based on the previous studies’ findings, they collected nearly 3,000 data points related to how each of these factors might impact the severity or prevalence of infectious disease outbreaks.

Researchers aimed to avoid a human-centric approach to their analysis, considering also how plants and animals would be at risk from pathogens. Their conclusions showed that four of the examined factors—climate change, chemical pollution, the introduction of non-native species to new areas and biodiversity loss—all increased the likelihood of spreading disease, with the latter having the most significant impact.

Disease and mortality were nearly nine times higher in areas of the world where human activity has decreased biodiversity, compared to the levels expected by Earth’s natural variation in biodiversity, per the Washington Post .

Scientists hypothesize this finding could be explained by the “dilution effect”: the idea that pathogens and parasites evolve to thrive in the most common species, so the loss of rarer creatures makes infection more likely.

“That means that the species that remain are the competent ones, the ones that are really good at transmitting disease,” Rohr tells the New York Times ’   Emily Anthes.

For example, white-footed mice, the main carriers of Lyme disease, have become one of the most dominant species in their habitat as other, rarer animals have disappeared—a change that might have played a role, among other factors, in driving rising rates of Lyme disease in the United States.

One global change factor, however, actually decreased the likelihood of disease outbreaks: habitat loss and change. But here, context is key. Most habitat loss is linked to creating a single type of environment—urban ecosystems—which generally have good sanitation systems and less wildlife, reducing opportunities for disease spillover.

“In urban areas with lots of concrete, there is a much smaller number of species that can thrive in that environment,” Rohr tells the Guardian ’s Phoebe Weston. “From a human disease perspective, there is often greater sanitation and health infrastructure than in rural environments.”

Deforestation, another type of habitat loss, has been shown to increase the likelihood of disease. The incidence of malaria and Ebola , for example, worsens in such instances.

The new work adds to past research on how human activity can prompt the spread of disease. For instance, climate change-induced permafrost melt may release pathogens from the Arctic , a concern that’s been well-documented in recent years. And both habitat loss and climate change may force some animals to move closer together—and closer to humans — increasing the potential for transmitting disease .

Additionally, the research signals the need for public health officials to remain vigilant as the effects of human-caused climate change play out, experts say.

“It’s a big step forward in the science,” Colin Carlson , a global change biologist at Georgetown University who was not an author of the new analysis, tells the New York Times. “This paper is one of the strongest pieces of evidence that I think has been published that shows how important it is health systems start getting ready to exist in a world with climate change, with biodiversity loss.”

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Christian Thorsberg | READ MORE

Christian Thorsberg is an environmental writer and photographer from Chicago. His work, which often centers on freshwater issues, climate change and subsistence, has appeared in Circle of Blue , Sierra  magazine, Discover  magazine and Alaska Sporting Journal .

Climate risk and the opportunity for real estate

Climate change, previously a relatively peripheral concern for many real-estate players, has moved to the top of the agenda. Recently, investors  made net-zero commitments, regulators developed reporting standards, governments passed laws targeting emissions, employees demanded action, and tenants demanded more sustainable buildings. At the same time, the accelerating physical consequences of a changing climate are becoming more pronounced as communities face storms, floods, fires, extreme heat, and other risks.

These changes have brought a sense of urgency to the critical role of real-estate leaders in the climate transition, the period until 2050 during which the world will feel both the physical effects of climate change and the economic, social, and regulatory changes necessary to decarbonize. The climate transition not only creates new responsibilities for real-estate players to both revalue and future-proof their portfolios but also brings opportunities to create fresh sources of value.

The combination of this economic transition and the physical risks of climate change has created a significant risk of mispricing real estate across markets and asset classes. For example, a major North American bank conducted analysis that found dozens of assets in its real-estate portfolio that would likely be exposed to significant devaluations within the next ten years due to factors including increased rates of flooding and job losses due to the climate transition. Additionally, a study of a diversified equity portfolio found that, absent mitigating actions, climate risks could reduce annual returns toward the end of the decade by as much as 40 percent.

Leading real-estate players will figure out which of their assets are mispriced and in what direction and use this insight to inform their investment, asset management, and disposition choices. They will also decarbonize their assets, attracting the trillions of dollars of capital that has been committed to net zero and the thousands of tenants that have made similar commitments. They will then create new revenue sources related to the climate transition.

Building climate intelligence is central to value creation and strategic differentiation in the real-estate industry. But the reverse is also true: real estate is central to global climate change mitigation efforts. Real estate drives approximately 39 percent of total global emissions. Approximately 11 percent of these emissions are generated by manufacturing materials used in buildings (including steel and cement), while the rest is emitted from buildings themselves and by generating the energy that powers buildings. 1 2019 global status report for buildings and construction , International Energy Agency, December 2019.

In addition to the scale of its contribution to total emissions, real estate is critical in global decarbonization efforts for reasons likely to be compelling for investors, tenants, and governments. Significant reductions in emissions associated with real estate can be achieved with positive economics through technologies that already exist. For example, upgrading to more energy-efficient lighting systems and installing better insulation have positive financial returns. Today, newer technologies also make low-carbon heating and cooling systems, such as heat pumps and energy-efficient air conditioning, more cost competitive in many markets and climates. These cost-effective upgrades can create meaningful change while also derisking assets.

We suggest three actions real-estate players can take to thrive throughout the climate transition:

• Incorporate climate change risks into asset and portfolio valuations. This requires building the analytical capabilities to understand both direct and indirect physical and transition risks.
• Decarbonize real-estate assets and portfolios.
• Create new sources of value and revenue streams for investors, tenants, and communities.

Fundamental changes brought on by the climate transition will open new dimensions of competitive differentiation and value creation for real-estate players. More important, leaders will make a valuable contribution to the world’s ability to meet the global climate challenge.

Incorporate climate change risks into asset and portfolio valuations

Climate change’s physical and transition risks touch almost every aspect of a building’s operations and value. Physical risks are hazards caused by a changing climate, including both acute events, such as floods, fires, extreme heat, and storms, and chronic conditions, such as steadily rising sea levels and changing average temperatures. Transition risks include changes in the economy, regulation, consumer behavior, technology, and other human responses to climate change.

We do mind the gap

As we work with real-estate firms, we notice that investment teams increasingly recognize the impact of climate change on asset values. As one leader of valuations at a major real-estate-services firm recently commented to us: “This is the greatest deviation between modeled valuation and actual price that I’ve ever seen, and it’s because of climate.” A chief operating officer of a diversified real-estate investor told us, “We’ve seen underperformance of a cluster of our assets due to climate-related factors that just weren’t considered in our investment theses.”

The industry at large senses how values are shifting. A recent survey of finance experts and professionals conducted by researchers at New York University found that those who think real-estate asset prices reflect climate risks “not enough” outnumber those who think they reflect climate risks “too much” by 67 to 1 (in comparison with stock prices, in which the ratio was 20 to 1). 1 Johannes Stroebel and Jeffrey Wurgler, “What do you think about climate finance?,” Harvard Law School Forum on Corporate Governance, September 3, 2021. The International Renewable Energy Agency has estimated that $7.5 trillion worth of real estate could be “stranded”; these are assets that will experience major write-downs in value given climate risks and the economic transition, making real estate one of the hardest-hit sectors. 2 Jean Eaglesham and Vipal Monga, “Trillions in assets may be left stranded as companies address climate change,” Wall Street Journal , November 20, 2021.

Physical and transition risks can affect assets, such as buildings, directly or indirectly, by having an impact on the markets with which the assets interact. A carbon-intensive building obviously faces regulatory, tenancy, investor, and other risks; over the long term, so does a building that exists in a carbon-intensive ecosystem. For example, a building supplied by a carbon-intensive energy grid or a carbon-intensive transportation system is exposed to the transition risks of those systems as well. All these changes add up to substantial valuation impacts for even diversified portfolios—an increasingly pressing concern for real-estate companies (see sidebar, “We do mind the gap”).

Physical risks, both direct and indirect, have an uneven effect on asset performance

Several major real-estate companies have recently conducted climate stress tests on their portfolios and found a significant impact on portfolio value, with potential losses for some debt portfolios doubling over the next several years. Notably, they found significant variation within the portfolios. Some assets, because of their carbon footprint, location, or tenant composition, would benefit from changes brought on by the climate transition, while others would suffer significant drops in value. The challenge for players is to determine which assets will be affected, in what ways, and how to respond. There is also opportunity for investors who can identify mispriced assets.

Direct physical consequences can be conspicuous: the value of homes in Florida exposed to changing climate-related risks are depressed by roughly $5 billion relative to unexposed homes. According to the Journal of Urban Economics , after Hurricane Sandy, housing prices were reduced by up to 8 percent in New York’s flood zones by 2017, reflecting a greater perception of risk by potential buyers. 2 Francesc Ortega and Süleyman Taspinar, “Rising sea levels and sinking property values: Hurricane Sandy and New York’s housing market,” Journal of Urban Economics , July 2018, Volume 106. In California, there has been a 61 percent annual jump in nonrenewals of insurance (due to higher prices and refused coverage) in areas of moderate-to-very-high fire risk. 3 Elaine Chen and Katherine Chiglinsky, “Many Californians being left without homeowners insurance due to wildfire risk,” Insurance Journal , December 4, 2020.

The indirect impacts of physical risk on assets can be harder to perceive, causing some real-estate players to underestimate them. For example, in 2020, the McKinsey Global Institute modeled expected changes in flooding due to climate change in Bristol, England . A cluster of major corporate headquarters was not directly affected, but the transportation arteries to and from the area were. The water may never enter the lobby of the building, but neither will the tenants.

The climate transition will affect both individual buildings and entire real-estate markets

The investments required to avoid or derisk the worst physical risks will drive a historic reallocation of capital . This will change the structure of our economy and impact the value of the markets, companies, and companies’ locations. These momentous changes require real-estate players to look ahead for regulatory, economic, and social changes that could impact assets.

Among the most direct climate-transition impacts are regulatory requirements to decarbonize buildings, such as New York City’s Local Law 97. In June 2019, the Urban Green Council found that retrofitting all 50,000 buildings covered by the law would create retrofit demand of up to $24.3 billion through 2030. 4 Justin Gerdes, “After pandemic, New York’s buildings face daunting decarbonization mandate,” Greentech Media, April 23, 2020. Standard property valuation models generally do not account for the capital costs required for a building to decarbonize, and investors and operators are often left with a major capital expense or tax that wasn’t considered in the investment memo.

There is also a host of less direct but potentially more significant transition risks that affect whole markets. For example, some carbon-intensive industries are already experiencing rapid declines or fluctuations. In Calgary, for example, the combination of oil price volatility and market-access issues (driven by climate change–related opposition to pipelines) has dramatically depressed revenues from some buildings. Vacancy rates in downtown Calgary reached about 30 percent, a record high, as of January 2021. Investors exposed to the Calgary market have seen their asset values drop precipitously and are left trying to either hold on and hope for a reversal of fortunes or exit the assets and take a significant loss.

Real-estate players should build the capabilities to understand climate-related impacts on asset performance and values

Real-estate owners and investors will need to improve their climate intelligence to understand the potential impact of revenue, operating costs, capital costs, and capitalization rate on assets. This includes developing the analytical capabilities to consistently assess both physical and transition risks. Analyses should encompass both direct effects on assets and indirect effects on the markets, systems, and societies with which assets interact (Exhibit 1).

Portfolio and asset managers can map, quantify, and forecast climate change’s asset value impact

To understand climate change impact on asset values, landlords and investors can develop the following capabilities to understand and quantify risks and opportunities:

• Prioritize. Create a detailed assessment of the asset or portfolio to determine which physical and transition risks are most important and which are less important (using criteria such as the probability of a risk occurring or the severity of that risk).
• Map building exposures. Determine which buildings are exposed to risks, either directly (for example, having to pay a carbon tax on building emissions) or indirectly (for example, exposure to reduction in occupancy as tenants’ industries decline because of a carbon tax), and the degree of exposure (for example, how high floodwaters would reach). This could require detailed modeling of physical hazards (for example, projected changes in flood risks as the climate changes) or macro- or microeconomic modeling (for example, projected GDP impacts based on the carbon price impact on a local geography’s energy production mix).
• Quantify portfolio impact. Combine assessments of the economic risks on individual buildings into an impact map that enables visualization of the entire portfolio (Exhibit 2). This requires combining knowledge of the potential risk or opportunity and an understanding of what drives the economics of a building (including drivers of net operating income, tenancy mix, and areas of cost variability).
• Take action. These capabilities cannot be isolated in a research or environmental, social, and governance (ESG) function but should directly inform investment management, lease pricing, capital attraction and investor relations, asset management, tenant attraction, development, and other core businesses. The processes within organizations must shift to ensure that climate-related insights can be a source of real competitive advantage.

A portfolio revaluation informed by climate change risks can lead to hard choices but will also open the door to acting on decarbonization and exploring new opportunities.

Decarbonize buildings and portfolios

McKinsey research estimates approximately $9.2 trillion in annual investment will be required globally to support the net-zero transition . If the world successfully decarbonizes, the 2050 economy will look fundamentally different from the current economy. If it doesn’t successfully decarbonize, the world will experience mounting physical risks that will strain the foundations of the global economy and society. In either case, the places where people live, work, shop, and play will fundamentally change.

Decarbonizing real estate requires considering a building’s ecosystem

Ultimately, the only way to reduce the risks of climate change is to decarbonize. Real-estate players have a wide array of options for how to proceed, including low-carbon development and construction ; building retrofits to improve energy efficiency; upgrades to heating, cooling, and lighting technology; and technology to manage demand and consumption. But decarbonization is not solely a technical challenge. To develop the most appropriate path, real-estate players need to understand the range of decarbonization options and their financial and strategic costs and benefits.

Decarbonizing real estate

To decarbonize, industry players can take the following steps:

• Understand the starting point. Quantify baseline emissions of each building. This helps real-estate players prioritize where to start (for example, individual buildings, asset classes, or regions) and determine how far there is to go to reach zero emissions.
• Set targets. Decide which type of decarbonization target to set. There is a range of potential target-setting standards that take different approaches (for example, measuring absolute emissions versus emissions intensity, or setting targets at the sector level versus asset level). Players should develop a “house view” on targets that achieve business, investor, stakeholder, regulatory, and other objectives.
• Identify decarbonization levers. Build an asset- or portfolio-level abatement curve. A marginal abatement cost curve  provides a clear view of the potential cost/return on investment of a given emissions-reduction lever along with the impact of that lever on emissions reduction. This approach can be complemented with market and policy scenarios that change the relative costs and benefits of each potential abatement lever.
• Execute. Set up the mechanisms to effectively deploy the decarbonization plan. These may involve making changes to financing and governance, stakeholder engagement (investors, joint-venture partners, operators, and tenants), and a range of operational and risk-management aspects of the business.
• Track and improve. As investors, lenders, and tenants make their own decarbonization commitments, they will need to demonstrate that their real estate is indeed decarbonizing. Thus, much of the value of decarbonizing will come from the ability to demonstrate emissions reduction to potential stakeholders. Building the ability to monitor and progressively reduce emissions on the path to net zero will create an opportunity for players to differentiate.

Create new sources of value and revenue streams for investors, tenants, and communities

As the economy decarbonizes, real-estate players can use their locations, connections to utility systems, local operational footprints, and climate intelligence to create new revenue streams, improve asset values, or launch entirely new businesses.

Opportunities include the following:

• Local energy generation and storage. Real-estate firms can use their physical presence to generate and store energy. For example, property developers have been outfitting buildings with solar arrays and batteries, helping to stabilize energy grids and reduce the costs associated with clean energy. 5 “5 ways clean tech is making commercial RE more energy efficient,” Jones Lang LaSalle, April 20, 2021.
• Green buildings to attract more tenants. Developers and property managers can invest in developing green buildings or retrofitting older buildings to make them green to meet the growing appetite for sustainable workplaces and homes.
• Green-building materials. Players can explore the advantages of green steel, tall timber, modular construction, and other emerging technologies and materials that may have additional benefits, such as faster and lower-cost construction.
• Extra services on-site. Firms can introduce new revenue streams, including vehicle charging, green-facilities management, and other on-site services that enable occupants’ sustainable preferences.
• Services for reducing and tracking emissions. Firms can support occupants by tracking emissions and offering solutions to reduce carbon footprints. These services could include smart sensors and tracking energy consumption through heating, cooling, lighting, and space management.
• Differentiated capital attraction. Given the volume of capital that has already been committed to achieving net zero, firms that are able to decarbonize will have an advantage in attracting capital. Real-estate players may, for example, create specific funds for net-zero buildings or investment themes that support community-scale decarbonization.

The coming climate transition will create seismic shifts in the real-estate industry, changing tenants’ and investors’ demands, the value of individual assets, and the fundamental approaches to developing and operating real estate. Smart players will get ahead of these changes and build climate intelligence early by understanding the implications for asset values, finding opportunities to decarbonize, and creating opportunity through supporting the transition.

Real estate not only will play a critical role in determining whether the world successfully decarbonizes but also will continue to reinvent the way we live, work, and play through these profound physical and economic changes.

This article was edited by Katy McLaughlin, a senior editor in the southern California office.

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The Hard Side of Change Management

• Harold L. Sirkin,
• Perry Keenan,
• Alan Jackson

Everyone agrees that managing change is tough, but few can agree on how to do it. Most experts are obsessed with “soft” issues, such as culture and motivation, but, say the authors, focusing on these issues alone won’t bring about change. Companies also need to consider the hard factors—like the time it takes to complete a change initiative, the number of people required to execute it, and so forth.

When the authors studied change initiatives at 225 companies, they found a consistent correlation between the outcomes of change programs (success versus failure) and four hard factors, which they called DICE: project duration, particularly the time between project reviews; integrity of performance, or the capabilities of project teams; the level of commitment of senior executives and staff; and the additional effort required of employees directly affected by the change. The DICE framework is a simple formula for calculating how well a company is implementing, or will be able to implement, its change initiatives. The framework comprises a set of simple questions that help executives score their projects on each of the four factors; the lower the score, the more likely the project will succeed. Companies can use DICE assessments to force conversations about projects, to gauge whether projects are on track or in trouble, and to manage project portfolios.

The authors have used these four factors to predict the outcomes and guide the execution of more than 1,000 change management programs worldwide. Not only has the correlation held, but no other factors (or combination of factors) have predicted outcomes as successfully.

Companies must pay as much attention to the hard side of change management as they do to the soft aspects. By rigorously focusing on four critical elements, they can stack the odds in favor of success.

The Idea in Brief

Two out of every three transformation programs fail. Why? Companies overemphasize the soft side of change: leadership style, corporate culture, employee motivation. Though these elements are critical for success, change projects can’t get off the ground unless companies address harder elements first.

The essential hard elements? Think of them as DICE:

• D uration: time between milestone reviews—the shorter, the better
• I ntegrity: project teams’ skill
• C ommitment: senior executives’ and line managers’ dedication to the program
• E ffort: the extra work employees must do to adopt new processes—the less, the better

By assessing each DICE element before you launch a major change initiative, you can identify potential problem areas and make the necessary adjustments (such as reconfiguring a project team’s composition or reallocating resources) to ensure the program’s success. You can also use DICE after launching a project—to make midcourse corrections if the initiative veers off track.

DICE helps companies lay the foundation for successful change. Using the DICE assessment technique, one global beverage company executed a multiproject organization-wide change program that generated hundreds of millions of dollars, breathed new life into its once-stagnant brands, and cracked open new markets.

The Idea in Practice

Conducting a DICE Assessment

Your project has the greatest chance of success if the following hard elements are in place:

A long project reviewed frequently stands a far better chance of succeeding than a short project reviewed infrequently. Problems can be identified at the first sign of trouble, allowing for prompt corrective actions. Review complex projects every two weeks; more straightforward initiatives, every six to eight weeks.

A change program’s success hinges on a high-integrity, high-quality project team. To identify team candidates with the right portfolio of skills, solicit names from key colleagues, including top performers in functions other than your own. Recruit people who have problem-solving skills, are results oriented, and are methodical but tolerate ambiguity. Look also for organizational savvy, willingness to accept responsibility for decisions, and a disdain for the limelight.

If employees don’t see company leaders supporting a change initiative, they won’t change. Visibly endorse the initiative—no amount of public support is too much. When you feel you’re “talking up” a change effort at least three times more than you need to, you’ve hit it right.

Also continually communicate why the change is needed and what it means for employees. Ensure that all messages about the change are consistent and clear. Reach out to managers and employees through one-on-one conversations to win them over.

If adopting a change burdens employees with too much additional effort, they’ll resist. Calculate how much work employees will have to do beyond their existing responsibilities to implement the change. Ensure that no one’s workload increases more than 10%. If necessary, remove nonessential regular work from employees with key roles in the transformation project. Use temporary workers or outsource some processes to accommodate additional workload.

Using the DICE Framework

Conducting a DICE assessment fosters successful change by sparking valuable senior leadership debate about project strategy It also improves change effectiveness by enabling companies to manage large portfolios of projects. Example: 

A manufacturing company planned 40 projects as part of a profitability-improvement program. After conducting a DICE assessment for each project, leaders and project owners identified the five most important projects and asked, “How can we ensure these projects’ success?” They moved people around on teams, reconfigured some projects, and identified initiatives senior managers should pay more attention to—setting up their most crucial projects for resounding success.

When French novelist Jean-Baptiste Alphonse Karr wrote “Plus ça change, plus c’est la même chose,” he could have been penning an epigram about change management. For over three decades, academics, managers, and consultants, realizing that transforming organizations is difficult, have dissected the subject. They’ve sung the praises of leaders who communicate vision and walk the talk in order to make change efforts succeed. They’ve sanctified the importance of changing organizational culture and employees’ attitudes. They’ve teased out the tensions between top-down transformation efforts and participatory approaches to change. And they’ve exhorted companies to launch campaigns that appeal to people’s hearts and minds. Still, studies show that in most organizations, two out of three transformation initiatives fail. The more things change, the more they stay the same.

• HS Harold L. Sirkin is a Chicago-based senior partner of The Boston Consulting Group, and coauthor of Globality: Competing with Everyone from Everywhere for Everything .
• PK Perry Keenan is a senior partner and managing director of The Boston Consulting Group based in Chicago. He is a member of the firm’s senior leadership teams for the operations and organization practice areas and the global leader for the firm’s change management topic.
• AJ Alan Jackson ( [email protected] ) is a BCG senior vice president in Sydney, Australia. Visit the BCG website for more on change management and an interactive DICE tool.

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How climate change is raising the risks of another pandemic

Evidence is mounting that human disruptions to natural ecosystems are raising risks of disease spread, according to a new study.

As humans degrade Earth’s environment, we have created a world in which diseases may be increasingly apt to fester and multiply.

Infection-spreading creatures such as mosquitoes and ticks are thriving on a planet warmed by a blanket of fossil fuel emissions. When pollution, hunting or development push rare organisms to extinction, parasites proliferate because they have evolved to target the most abundant species.

And then there are the harms caused when humans introduce nonnative plants and animals or chemicals such as herbicides and fungicides to fragile ecosystems. That exacerbates losses in biodiversity that leave surviving populations more vulnerable to illness, according to research published Wednesday in the journal Nature.

Researchers said the study is the first to look at the ways such a variety of environmental problems can compound disease risks. It combined hundreds of studies and thousands of observations of all kinds of creatures — humans and other mammals, fish, reptiles, amphibians, worms and arthropods — and all kinds of pathogens, such as viruses, bacteria and fungi.

The analysis reinforced the findings of many of those inquiries: that a hotter world of ravaged ecosystems is one that is more hospitable to many parasites, and less so to humans and other life.

The connection appeared with all types of infections and their hosts, suggesting that as the planet continues to warm and humans continue to disrupt nature, increases in disease spread “will be consistent and widespread,” said Jason Rohr, a professor of biological sciences at the University of Notre Dame and one of the study’s authors. The link was just as clear with humans as it was with wildlife and plants, he added.

“That is despite all the efforts we’re making to control and prevent diseases,” Rohr said.

And if diseases become more rampant in the animal world, that could mean the likelihood of “spillover” events exposing humans to new pathogens — the likely origin of covid-19 , and a feared outcome of the ongoing spread of H5N1 bird flu — also will increase, the study suggests.

“It could mean that by modifying the environment, we increase the risks of future pandemics, ” Rohr said.

As grim as the findings appear, they underscore that actions to protect the planet can also serve to improve health, researchers said.

“This adds to a very long list of reasons we should be rapidly moving away from fossil fuels and trying to mitigate the impacts of climate change,” said Felicia Keesing, a professor at Bard College who was not involved in the study but whose research focuses on biodiversity and disease risks.

The study used observations of disease outcomes involving a wide variety of parasites infecting a spectrum of hosts around the world. The observations also included information about a range of human influences on the environment: biodiversity changes, chemical pollution, climate change, habitat loss or change, and introduction of nonnative species.

Biodiversity has a natural gradient across the planet, with the greatest numbers of species found closest to the equator and at moderate elevations. The researchers gauged the effect of human-caused biodiversity loss on diseases by comparing the observations of infections around the world to average disease prevalence at varying levels of biodiversity across that natural gradient. In nature, reductions in biodiversity are associated with reductions in disease.

But when humans cause losses in biodiversity, diseases increase. The researchers found that levels of disease and mortality in environments affected by human-caused biodiversity losses were nearly nine times worse than disease outcomes expected under Earth’s natural biodiversity gradient. Rohr said that is probably because the loss of rarer creatures means pathogens have an easier time finding the more abundant species they have evolved to use as hosts.

The researchers also found that climate change and the introduction of nonnative species have significant links to worsened disease spread, though not as strong as the effect of biodiversity losses.

The analysis found one variable of human influence that actually decreased disease risks: habitat losses. Rohr said the researchers believe that is largely a function of urbanization: Cities tend to have better sanitation and health infrastructure, and they are simply home to fewer natural organisms, he said.

Skylar Hopkins, an assistant professor at North Carolina State University who was not involved in the research, cautioned against applying the findings too broadly. Analyses such as this one are composed of a selection of completed studies but cannot represent a truly random sample of pathogens and infections, she said. Not all parasites are “bad,” she added, and one also cannot assume that repairing lost biodiversity will undo an increase in disease.

The research published Wednesday builds on past findings that link disease spread with specific global changes.

For example, it is known that extreme heat and precipitation tied to human-caused climate change have allowed malaria cases to rise , and could drive them to surge even more dramatically in the decades ahead . Biodiversity losses are known to contribute to spillover of diseases such as covid-19, HIV/AIDS, Ebola and severe acute respiratory syndrome, or SARS.

But the researchers wrote that more needs to be learned about how humans’ many influences on the environment might be building upon each other.

“For example, climate change and chemical pollution can cause habitat loss and change, which in turn can cause biodiversity loss and facilitate species introductions,” the researchers wrote. New studies will need to examine whether those factors, in combination, serve to add, subtract or even multiply risks of disease spread.

Mawer Investment Management Ltd. Announces Risk Rating Change to Mawer U.S. Mid Cap Equity Fund

CALGARY, Alberta, May 17, 2024 (GLOBE NEWSWIRE) -- Mawer Investment Management Ltd. (Mawer) announced today the following risk rating change:

This change became effective on May 16, 2024 and will be reflected in the fund’s simplified prospectus and fund facts, which will be filed on about May 17, 2024.

Mawer reviews the risk rating for each fund at minimum on an annual basis, as well as when a fund undergoes a material change. The above noted change is the result of an annual review and is not the result of any changes to the investment objectives, strategies, or management of the fund. Mawer uses the investment risk classification methodology in National Instrument 81-102—Investment Funds.

About Mawer Investment Management Ltd.

Mawer is an independent investment firm managing portfolios for a broad range of foundations and not-for-profit organizations, pension plans, strategic alliances, and individual investors for over 50 years. For more information, visit Mawer at www.mawer.com.

For media inquiries, please contact: Joanna Crozier Head of Marketing and Communications +1 (403) 267-1964 [email protected]

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Loneliness Can Change the Brain

Feeling chronically disconnected from others can affect the brain’s structure and function, and it raises the risk for neurodegenerative diseases.

By Dana G. Smith

Everyone feels lonely from time to time — after, say, a move to a new school or city, when a child leaves for college, or following the loss of a spouse.

Some people, though, experience loneliness not just transiently but chronically. It becomes “a personality trait, something that’s pretty sticky,” said Dr. Ellen Lee, an associate professor of psychiatry at the University of California, San Diego. These individuals seem to have “this persistent emotion that then shapes their behavior.”

Research is mounting that this type of entrenched loneliness is bad for our health and can even change our brains, raising the risk for neurodegenerative diseases. Here’s what experts know about how chronic loneliness affects the brain, and some strategies to address it.

How does loneliness change the brain?

Humans evolved to be social creatures probably because, for our ancient ancestors, being alone could be dangerous and reduce the odds of survival. Experts think loneliness may have emerged as a unique type of stress signal to prompt us to seek companionship.

With chronic loneliness, that stress response gets stuck and becomes disadvantageous — similar to the way in which anxiety can shift a helpful fear response to a maladaptive mental illness.

“Small, transient episodes of loneliness really motivate people to then seek out social connection,” said Anna Finley, a postdoctoral research fellow at the Institute on Aging at the University of Wisconsin-Madison. “But in chronic episodes of loneliness, that seems to kind of backfire” because people become especially attuned to social threats or signals of exclusion, which can then make it scary or unpleasant for them to interact with others.

Research has shown that lonely people are hypersensitive to negative social words, like “disliked” or “rejected,” and to faces expressing negative emotions. What’s more, they show a blunted response to images of strangers in pleasant social situations, suggesting that even positive encounters may be less rewarding for them. In the brain , chronic loneliness is associated with changes in areas important for social cognition, self-awareness and processing emotions.

How could a subjective feeling have such a profound effect on the brain’s structure and functions? Scientists aren’t sure, but they think that when loneliness triggers the stress response , it also activates the immune system , increasing levels of some inflammatory chemicals. When they’re experienced for long periods of time, stress and inflammation can be detrimental for brain health, damaging neurons and the connections between them.

How does loneliness affect long-term brain health?

For years, scientists have known about a connection between loneliness and Alzheimer’s disease and other types of dementia . A study published late last year suggested that loneliness is associated with Parkinson’s disease , as well.

“Even low levels of loneliness increase risk, and higher levels are associated with higher risk” for dementia, said Dr. Nancy Donovan, director of the division of geriatric psychiatry at Brigham and Women’s Hospital. Dr. Donovan has shown that people who score higher on a measure of loneliness have higher levels of the proteins amyloid and tau — two of the hallmarks of Alzheimer’s disease — in their brains even before they show signs of cognitive decline.

Scientists think that the stress and inflammation caused by loneliness most likely contribute to the onset or acceleration of neurodegenerative diseases in older adults. The toll loneliness takes on the cardiovascular system, increasing blood pressure and heart rate, can also have a detrimental effect on the brain and probably plays a role, as well, Dr. Donovan said.

The more general way in which loneliness affects mental and physical health may also factor into cognitive decline. The feeling is closely linked to depression, another condition that increases the risk for dementia . And people who are lonely are less likely to be physically active and more likely to smoke cigarettes. “All those different things can affect how our brains age,” Dr. Lee said. “I think there are many paths to get from loneliness to cognitive decline.”

Most research on loneliness and neurodegeneration has been conducted on middle-aged and older adults, so experts don’t know if loneliness in childhood or young adulthood carries the same risk. However, Dr. Wendy Qiu, a professor of psychiatry and experimental pharmacology and therapeutics at Boston University School of Medicine, has found that if people in midlife feel lonely only transiently, not chronically, there is no increased risk for dementia.

With transient loneliness, the brain has the “ability to recover,” Dr. Qiu said. But if people “don’t have help to pull them out of the loneliness, and for a long time they feel lonely, it will be toxic for the brain.”

How can you combat chronic loneliness?

One of the most common recommendations is a little obvious: Try to make new friends . Whether that’s through art classes, sports teams, support groups or volunteer opportunities, the goal is to put yourself in places where people come together.

These types of engineered social situations have mixed results. Dr. Lee said they tend to work best if there is a “shared identity” among the people involved, like groups specifically for widows or for people with diabetes, so they have something to connect over.

The other side of the equation is addressing a person’s attitudes and thought patterns about social interactions through cognitive behavioral therapy. These approaches tend to be a little more effective, Dr. Lee said, because they “get to the root” of the problem, exploring what makes it hard for a person to interact with others.

The strategies may sound simple, but they’re easier said than done. “It’s a thorny problem,” Dr. Finley said. “Otherwise, I don’t think we would have the report from the Surgeon General saying we need to figure this out.”

Dana G. Smith is a Times reporter covering personal health, particularly aging and brain health. More about Dana G. Smith