Our changing climate is jeopardizing worker health and productivity. Companies need to adapt their operations

Smoke from Canadian wildfires engulfs New York City on Jun. 7.
Smoke from Canadian wildfires engulfs New York City on Jun. 7.
Kena Betancur - VIEWpress - Getty Images

Climate change is the single biggest health threat facing humanity, according to the World Health Organization (WHO). Today, we have proof that a changing climate puts the health of workers in jeopardy and reduces productivity.

Nearly half of the U.S. workforce (65 million people) face climate-related health risks, according to KFF, an independent health policy research, polling, and journalism nonprofit. In the last few months alone, we have seen this threat manifested in multiple climate events with devasting impacts. Major wildfires engulfed regions across North America as well as Hawaii, resulting in loss of life and economic hardship for millions of people. Beyond the burn zones, dangerous smoke affected millions more, impacting people with preexisting health conditions. In parallel, record temperatures and extended heat waves led to hospitalizations and heat-related deaths.

The fact is that climate, human health, and business performance are inextricably linked. If the last few months offer a preview of what’s to come, it should galvanize business leaders to better understand and mitigate the risks climate-related events pose to their people–the most valuable and important contributors to business success. We have an opportunity–and frankly, an obligation–to protect our employees and to take important steps to build a climate-resilient workforce.

A growing threat to employee health and productivity

Beyond the immediate potential for loss of life from extreme weather, business leaders need to be aware of the potential physical and mental impacts of climate events on employees. 

Living through an extreme weather event can be traumatizing, with mental and emotional effects potentially lingering long after the danger subsides, including post-traumatic stress disorder, depression, and prolonged stress. Following Hurricane Katrina, one out of every five people who experienced the storm suffered PTSD for years, according to the Marsh McLennan report Sunk Costs, which explores the socioeconomic impacts of flooding.

Healthcare costs associated with wildfires can dwarf the immediate economic damages. Mortality and morbidity costs due to exposure to fine particulate air pollution from wildfires in the U.S. are estimated to be between $11 billion and $20 billion a year for short-term exposures, and $76 billion to $130 billion a year for long-term exposures, according to research from the EPA.

When it comes to extreme heat, studies have shown that rising temperatures can produce more drug-resistant infections and pathogens, drive higher levels of anxiety, depression, and violence, and increase worker illness and injury.

Beyond the human toll on employees, there is also a real cost to employers through increased expenses and lost productivity. Research from Loughborough University found that as temperatures reach 90 degrees Fahrenheit (32 degrees Celsius), worker productivity, particularly for those employed in labor-intensive or outdoor professions, can decline by 25%. Above 100 degrees, productivity decreases by 70%. The financial impact of lost productivity is staggering–estimated by the Adrienne Arsht-Rockefeller Foundation Resilience Center to now exceed $100 billion a year and is projected to top $500 billion annually by 2050.

Even some employees working in air-conditioned settings are feeling the heat, particularly those who work in environments that can be challenging to cool consistently, such as kitchens, factories, or warehouses. Increased costs for employers can include expenses associated with installing new air-conditioning systems, work delays, and a rise in health claims.

A pressing need for empathy and action

The U.S. government has recognized the need to better protect workers from extreme climate events. In September 2021, the White House announced an interagency effort to increase worker protections. Regulations from the Occupational Health and Safety Administration (OSHA) are in development.

The reality is that both government and business have a role to play in addressing this growing health imperative. We need forward-thinking leaders from the private sector to recognize this imperative, adopt a proactive, health-forward mindset, and help develop innovative solutions.

That’s why Mercer and the CDC Foundation are joining forces with the Health Action Alliance to create the National Commission on Climate and Workforce Health, a bold, new effort to meet this moment with the research, insights, and strategies to help employers mitigate the effects of extreme weather on their people and operations.

Other organizations around the world are also responding to the necessity of addressing the health impacts of climate change. The UN is introducing its first-ever “Day of Health” next month as part of COP28 in an attempt to facilitate discussions among key stakeholders. The National Institutes of Health has launched a Climate Change and Health Initiative to work across its institutes to mitigate health threats from climate change. Each of these will help raise awareness around the health-specific risks we face and build momentum toward collaborating on solutions.

Our changing climate challenges all businesses, organizations, communities, and individuals to adapt. Building a climate-resilient workforce is a strategic business imperative. We can work together to create proactive solutions for a safe, healthy, and productive workforce.

Martine Ferland is the CEO of Mercer. Dr. Judy Monroe is the President and CEO of the CDC Foundation. More information about the National Commission on Climate and Workforce Health can be found at ClimateHealthCommission.org.

More must-read commentary published by Fortune:

The opinions expressed in Fortune.com commentary pieces are solely the views of their authors and do not necessarily reflect the opinions and beliefs of Fortune.