Extreme heat set records for health perils in 2023
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Illustration: Annelise Capossela/Axios
Climate change exposed people to an average of 50 more days of health-threatening temperatures around the world last year and drove heat-related deaths to record highs, according to an annual report published Wednesday.
Why it matters: The Lancet Countdown on Health and Climate Change represents the most up-to-date assessment of the connection between health and climate change and includes sweeping recommendations for the U.S., including a call for ending fossil fuel expansion specifically because of the health consequences.
What they found: Heat-related deaths last year in people over age 65 increased by 167% globally above levels seen in the 1990s — nearly three times more than what would have been expected if temperatures had not changed.
- People were also exposed to an average of 1,512 hours of high temperatures that posed at least a moderate risk of heat stress when doing light exercise such as walking or cycling — a 27.7% increase on the 1990-1999 yearly average.
- Conditions were ripe for the spread of more deadly mosquito-borne infectious diseases, with dengue cases reaching an all-time high of over 5 million infections reported in more than 80 countries and territories in 2023.
- On a more positive note, the report found deaths from fossil fuel-derived air pollution fell almost 7% from 2016 to 2021, with most of this decline due to efforts to reduce pollution from coal burning.
The annual Lancet Countdown draws on the work of 122 leading experts worldwide. The U.S.-focused section reflects steps the Biden administration took to meet climate goals, and nearly $370 billion of investments the Inflation Reduction Act directed for clean energy, environmental justice and other initiatives.
Threat level: Despite that progress, the report said children born today can expect poorer air quality, hotter days and lifelong social and community disruptions from climate change.
- Just since September, nearly a third of the U.S. was in a state of drought, Hurricane Helene caused hundreds of deaths in the South, and Hurricane Milton followed closely, causing cascading social and economic disruption.
- The report singles out the health care sector for contributing 8.5% of U.S. greenhouse gas emissions and calls for steps to reduce emissions from hospitals and the broader medical supply chain.
- It predicts extreme heat, wildfire smoke, floods and storms could continue to stress the health system, noting how the twin hurricanes in September and October ravaged hospitals and clinics in the southeast.
What they're saying: The experts recommend phasing out fossil fuel investments and subsidies and expanding funding for non-combustion renewables and other climate action to protect health.
- "People's health must be put front and center of climate change policy to ensure the funding mechanisms protect well being, reduce health inequities and maximize health gains, especially for the countries and communities that need it most," said Anthony Costello, a professor at University College London and co-chair of the Lancet Countdown.
Our thought bubble, from Axios senior climate reporter Andrew Freedman: Human-caused climate change increases the likelihood and severity of heat waves, high-end hurricanes and precipitation extremes, such as drought conditions. Multiple studies have found that, in fact, certain heat waves would have been impossible in a world without climate change.
