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2024 Lancet report on climate change reveals record-breaking health threats associated with climate inaction

November 04, 2024

Three experts from Yale’s Center on Climate Change and Health contributed to this year’s report

“This year’s stocktake of the imminent health threats of climate inaction reveals the most concerning findings yet in our eight years of monitoring,” warned Dr Marina Romanello, Executive Director of the Lancet Countdown at University College London. “Once again, last year broke climate change records—with extreme heat waves, deadly weather events, and devastating wildfires affecting people around the world. No individual or economy on the planet is immune from the health threats of climate change. The relentless expansion of fossil fuels and record-breaking greenhouse gas emissions compound these dangerous health impacts, and are threatening to reverse the limited progress made so far, and to put a healthy future further out of reach.”

The 2024 Lancet Countdown on health and climate change, an annual international assessment of progress toward the climate mitigation goals of the 2015 Paris Agreement — co-authored this year by three members of the Yale Center on Climate Change and Health — contains some of the most dire projections to date associated with persistent global inaction over the pressing climate emergency.

Among the report’s key findings:

  • In 2023, people were exposed to, on average, an unprecedented 50 more days of health-threatening temperatures than expected without climate change. Extreme drought affected 48% of the global land area - the second-highest level ever recorded – and the higher frequency of heatwaves and droughts was associated with 151 million more people experiencing moderate or severe food insecurity than the annual average between 1981 and 2010.
  • Governments and companies are “fueling the fire" with persistent investment in fossil fuels, all-time high energy-related greenhouse gas emissions, and years of delays in adaptation to climate change that are narrowing the survival chances of people across the globe.
  • Financial resources to deliver net zero emissions and secure a healthy future are available. Yet governments and companies are spending trillions of dollars on fossil fuel subsidies and investments that are making climate change worse – money that should be redirected towards clean renewable energy and activities that benefit people’s health, livelihoods, and wellbeing.

Amidst these concerning findings, the report highlights new opportunities to put health at the center of the world’s response to climate change, including at the upcoming annual United Nations Climate Change Conference (COP 29) in Azerbaijan, November 11-22. The 2024 Lancet Countdown report, published Oct. 30, contributes to the evidence needed to inform these negotiations and deliver truly health-protecting climate change action.

Three members of the Yale Center on Climate Change and Health (YCCCH) served as authors for this year’s Lancet report – Dr. Jodi Sherman, MD, associate professor of anaesthesiology at the Yale School of Medicine and of epidemiology (environmental health sciences) at the Yale School of Public Health (YSPH), and director of the Program on Health Care Environmental Sustainability (Y-PHES) within YCCCH; Dr. Lingzhi Chu, PhD, postdoctoral associate (environmental health sciences) at YSPH; and Dr. Robert Dubrow, MD, PhD, professor emeritus and senior research scientist in epidemiology (environmental health sciences) at YSPH, and co-faculty director of YCCCH. The eighth annual report tracked 53 separate indicators.

In the report, Dr. Sherman contributed to the indicator entitled “Health care sector emissions and harms,” which found that greenhouse gas emissions from the health care sector accounted for 4.6% of global emissions in 2021. In addition, air pollution from the health care sector caused the loss of 4.6 million disability-adjusted life years. According to Dr. Sherman, “The health care system has a special obligation to do its share to reduce its greenhouse gas emissions to net-zero. There is plenty of know-how on what strategies work. What’s required is prioritizing actions now, not at some future ‘more convenient’ date. Many decarbonization strategies can also improve health system resilience and should be approached in concerted coordination by health system leaders.”

Drs. Dubrow and Chu were responsible for the indicator entitled “Benefits and harms of air conditioning,” which found that in 2021, 48.4% of very high Human Development Index country households, but only 4.7% of low HDI country households, had air conditioning, illustrating striking inequities in access to this life-saving technology. However, air conditioning contributes to greenhouse gas emissions, air pollution, urban heat islands, and summer power outages. Dr. Dubrow said, “Just like all households deserve adequate heating during cold weather, all households deserve adequate cooling during hot weather. We urgently need to ensure access to affordable, sustainable, and healthy cooling solutions for all people, including high-efficiency air conditioning powered by renewable energy in concert with passive and low-energy solutions.”

Responding to the report’s publication, UN Secretary-General, António Guterres (who was not involved in writing the report) said: “Record-high emissions are posing record-breaking threats to our health. We must cure the sickness of climate inaction – by slashing emissions, protecting people from climate extremes, and ending our fossil fuel addiction – to create a fairer, safer, and healthier future for all.”

The Lancet Countdown report represents the work of 122 leading experts from 57 academic institutions and UN agencies globally. Find out more and read the full report at lancetcountdown.org.