Climate Matters•May 27, 2024
Global Heat Action Day
KEY CONCEPTS
Climate change is making spells of dangerous heat hotter, longer, and more frequent.
Exposure to extreme heat can cause serious but preventable heat-related illness.
Heat Action Day, June 2, is an annual day for raising global awareness of heat risks and sharing simple ways to stay safe in our warming climate.
A new report assessed the influence of climate change on dangerous heat waves around the world over the past 12 months (May 15, 2023 to May 15, 2024).
Over this period, human-caused climate change boosted dangerous heat waves for billions, and made these events longer and more likely.
Heat Action Day: raising awareness of heat risks
The relentless rise in heat-trapping pollution (primarily from burning oil, coal, and natural gas) is making spells of dangerous heat hotter, longer, and more frequent across the globe.
More frequent extreme heat is not only an indicator of climate change — it’s also one of the most serious health risks in our warming climate.
Heat is the leading cause of weather-related deaths in the U.S., claiming more than 200 lives last year.
Exposure to extreme heat can cause heat-related illness including heat cramps, heat exhaustion, and even fatal medical emergencies such as heat stroke.
Heat-related illness is serious but preventable with simple steps to stay cool, hydrated, and informed.
Heat Action Day, on June 2, is an annual day for raising awareness of heat risks and sharing simple ways to stay safe and #BeatTheHeat.
Climate change is boosting dangerous heat waves for billions
Ahead of Heat Action Day, a new report from scientists at the World Weather Attribution initiative, the Red Cross Red Crescent Climate Centre, and Climate Central assessed the influence of human-caused climate change on dangerous heat waves over the past 12 months (May 15, 2023 to May 15, 2024).
Read the report: Climate Change and the Escalation of Global Extreme Heat: Assessing and Addressing the Risks
The period of analysis spans Earth’s hottest year on record (2023) and 11 consecutive months of record-breaking global temperatures (June 2023 - April 2024).
The report found that human-caused climate change is boosting dangerous heat waves for billions, and making these events longer and more likely. Key findings from the report include:
Using World Weather Attribution criteria, the study identified 76 extreme heat waves in 90 different countries. These events put billions of people at risk in densely populated areas of South and East Asia, the Sahel, and South America.
Over the 12-month period, 6.3 billion people (about 78% of the global population) experienced at least 31 days of extreme heat (above the 90th percentile) that was made at least two times more likely due to human-caused climate change (CSI level 2 or higher).
Over the last 12 months, human-caused climate change added an average of 26 more days of extreme heat (above the 90th percentile) than in a world without climate change.
Read the report: Climate Change and the Escalation of Global Extreme Heat: Assessing and Addressing the Risks
This report demonstrates that dangerous heat waves are: widespread; made longer and more likely by human-caused climate change; and often have under-reported impacts on health, agriculture, water supplies, and more.
Ways to #BeatTheHeat
Ultimately, rapidly cutting heat-trapping pollution is the most impactful and long-lasting action to slow the rate of warming and begin to reduce risky heat.
In the near-term, initiatives such as Heat Action Day can help raise awareness and keep people safe during hotter, longer, more likely extreme heat events.
Keeping people cool and safe: It’s important to remember that heat-related illness and death is preventable.
The National Integrated Heat Health Information System provides detailed guidance for staying safe before, during, and after heat waves.
For individuals, actions include limiting time outdoors during mid-day, drinking plenty of water, adjusting outdoor work hours, using cooling devices, and lowering body temperature with water.
Individual actions are often not enough to prevent widespread heat impacts, however.
Making communities, cities, and countries cooler and safer: Timely access to water, electricity, and shade is often out of reach for the most vulnerable. And the scale of heat risk requires collective action at the community, city, regional, and country levels.
Cities are hotspots of heat risk due to their high population density and land development patterns that can intensify heat in urban heat islands. But cities can also be the focal point for coordinated action to keep residents safe during extreme heat.
The Global Heat Health Information Network maintains a database of Heat Action Plans and Case Studies for cities around the world.
In the U.S., Miami, Phoenix, and King County, Washington are among the areas with coordinated heat action plans. Here are several ways to find heat action planning information for your area:
The EPA maintains a Heat Island Community Actions Database of measures that communities in the U.S. are taking to mitigate local heat island effects.
Find your state's emergency management agency to learn more about heat action plans in your area or check with local officials for available cooling centers.
The Low Income Home Energy Assistance Program (LIHEAP) aims to alleviate extreme heat stress for vulnerable populations. Explore LIHEAP data and mapping tools to see how and where historical funding has been allocated.
LOCAL STORY ANGLES
Is climate change influencing daily heat extremes in your local area?
Climate Central’s Climate Shift Index system provides tools, data, custom maps, and local alerts to answer this question in real-time. Here are three ways to use the Climate Shift Index this summer:
Use the tools. Climate Central’s Climate Shift Index map tool shows which parts of the world are experiencing high Climate Shift Index levels, every day. Explore the global Climate Shift Index map for today, tomorrow, and any day in the recent past.
Access KML to create custom Climate Shift Index maps. The Climate Shift Index is now available in KML format. Fill out this form to join our pilot project, receive the KML links, and create custom Climate Shift Index maps.
Sign up for alerts. Sign up here to receive custom email alerts when strong Climate Shift Index levels are detected in your local area.
How is extreme heat affecting public health in your local area?
Check out HeatRisk, an interactive map tool from the National Weather Service now available for the contiguous U.S. This color-numeric index shows current and forecast risk of daily local heat-related impacts. HeatRisk is unique because it takes into consideration: how unusual the heat is for the location and time of the year; heat duration (including both daytime and nighttime temperatures); whether those temperatures pose an elevated risk for local communities based on data from the Centers for Disease Control and Prevention (CDC). Additionally, the CDC’s Heat and Health Tracker maps heat-related illnesses at the census tract level in real time. Use the National Integrated Heat Health Information System (NIHHIS) Heat Equity Mapper to explore the burden of extreme heat at the census tract level. Check the U.S. Department of Health and Human Services monthly Climate and Health Outlook for extreme heat outlooks in your region throughout the summer.
CONTACT EXPERTS
Roop K. Singh (she/her)
Head of Urban and Attribution
Red Cross Red Crescent Climate Centre
Relevant expertise: heat risk, climate risk, disaster risk management
Contact: Singh@climatecentre.org
FIND EXPERTS
Submit a request to SciLine from the American Association for the Advancement of Science or to the Climate Data Concierge from Columbia University. These free services rapidly connect journalists to relevant scientific experts.
Browse maps of climate experts and services at regional NOAA, USDA, and Department of the Interior offices.
Explore databases such as 500 Women Scientists, BIPOC Climate and Energy Justice PhDs, and Diverse Sources to find and amplify diverse expert voices.
Reach out to your State Climate Office or the nearest Land-Grant University to connect with scientists, educators, and extension staff in your local area.
METHODOLOGY
For detailed methodology, please refer to the Methods section of the full report: Climate Change and the Escalation of Global Extreme Heat: Assessing and Addressing the Risks