Marsh McLennan addresses impact of extreme heat on health at COP29

Climate surprises in the US just keep coming: Temperatures in the Northeast have been running up to six degrees above the historical average since the official start of autumn in late September, drought is causing wildfires in New York and less snowfall is projected this winter across the country. To address these and other increasingly extreme weather conditions around the world, MMC’s representatives from Mercer, Marsh and Oliver Wyman are participating in the United Nations COP29 meeting in Baku, Azerbaijan.
Conversations at the event are reinforcing the call to action for employers in the US to anticipate the impact of climate on the health of workers and their communities. Amy Barnes, Head of Climate & Sustainability Strategy at Marsh, is on the ground at COP29, and noted, “The World Health Organization said that leaders may think they are discussing greenhouse gas emissions, but they are really discussing our health.”
Mercer health leaders have joined with colleagues from Marsh and Guy Carpenter to launch at the conference a new paper on the urgent need for businesses, governments and finance sectors to work together to transform society’s approach to heat risk management.
In the paper – “Turning down the heat: Pathways to adapt people, systems and economies from extreme heat risk” – Mercer’s National US Health Policy Leader Tracy Watts and ESG, Climate and Sustainability Global Head Cara Williams, help map out a strategic blueprint for governments and organizations alike. An excerpt:
Extreme heat poses serious health risks, including heat stress, heatstroke, respiratory issues and exacerbated cardiovascular conditions. Climate change is expected to cause US$2 billion–US$4 billion per year in direct health damage costs by 2030. Heatwaves, particularly in urban areas, can increase mortality rates and place strain on healthcare systems. This will be particularly prevalent in older populations.
Extreme heat also exacerbates existing social and racial disparities. Communities of color and low-income groups are more likely to live in regions with higher surface temperatures with limited access to greener, cooler spaces. These populations also tend to have higher rates of preexisting health conditions, making them more susceptible to heat-related complications. Heat that persists during the night is particularly challenging, as people who may have been able to benefit from air-conditioned workplaces, schools or public buildings during the day have to cope with over-heated houses in the night. Air conditioning is common in some places, but in regions not previously exposed to heat, informal settlements or low-income housing situations, there is often no proper cooling system in place.
In addition, the strain on health services and power grids during heat waves highlights the urgent need for infrastructure improvements to support community resilience to extreme heat events.
To transform the way society responds to extreme heat requires action from many stakeholders, but, in particular, there are key roles for corporates, public sector and government and insurance.
Businesses can increase heat resilience by moving from risk analysis to action.
Extreme heat will likely impact every business on the planet in some way, but no two companies’ exposure is identical. Some sectors, such as construction or agriculture, are much more vulnerable than others.
To increase heat resilience, corporate risk managers need thorough and tailored assessment to provide a clear picture of what’s at stake and what adaptation options are available.
This review should include assessment of the impact on workforce equity and sustainability as well as consideration of wider systems-level factors, including suppliers, infrastructure and customers. Impacts from heat can be indirect, delayed and invisible to existing tracking systems.
In North America, the National Commission on Climate and Workforce Health, in partnership with Mercer, promotes more leaders creating heat-stress-management plans that include training, prevention strategies and emergency response. Some key initiatives include providing easy access to cool drinking water, encouraging regular hydration breaks, encouraging lightweight clothing and scheduling strenuous activities for cooler parts of the day. For more information, download the Commission tip sheets. To stay on top of the work we are doing, sign up for the Commission’s newsletter here.
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