As the climate crisis raises average temperatures around the world, new data has shown that extreme heat is an increasingly pressing problem, surpassing other weather events in its lethality.
Floods, hurricanes, tornadoes and even frigid conditions all dwarf the total number of deaths each year from extreme heat, according to findings from the US National Weather Service.
The government agency found that in 2021, 190 people died from the heat, well above the 10-year average of 135. The next deadliest weather event was flooding, which claimed 146 lives in the same year, and 98 on average over the past decade.
Other dangerous weather included rip currents, cold weather and tornadoes, all of which were much deadlier than the 10-year average in 2021.
Extreme heat, as evidenced by this summer’s record highs around the world, is likely to be both more frequent and severe as a result of the climate crisis.
And other extreme weather events, such as floods, hurricanes and wildfires, are fueled by rising global temperatures caused by greenhouse gas emissions largely from the burning of fossil fuels.
In July, relentless heatwaves hit nearly every region in the US, prompting more than 150 million people to receive heat warnings and advisories. More than 350 new daily high temperature records were kept, according to the National Oceanic and Atmospheric Administration.
Last week, abnormally high temperatures in the Pacific Northwest led to at least 20 potential heat-related deaths.
But that pales in comparison to last year’s “heat dome” event in the Pacific Northwest, which killed more than 800 people in the US and Canada. The heat wave, where the normally temperate area saw the mercury rise well above 100 degrees Fahrenheit (38 degrees Celsius), was thought 150 times more likely due to the climate crisis.
Extreme heat can cause serious health problems when the body becomes severely dehydrated or loses the ability to cool itself. In less severe cases, heat can lead to fainting or cramping – but in severe cases, extreme heat can cause heat stroke as the body quickly reaches temperatures above 100F (38C).
Heat stroke can be fatal without emergency medical treatment. Some of the people most vulnerable to heat illness are the elderly, young children, pregnant people, and those with underlying health conditions such as heart disease.
In addition, heat can affect some communities more than others. Outdoor workers, poorer people and the homeless are all at greater risk of health problems from the heat, according to the World Health Organization (WHO).
A 2021 study found that in the U.S., poorer neighborhoods and neighborhoods with more black, Hispanic and Asian people were generally hotter than wealthier and whiter neighborhoods, which can put an extra heat load on those communities.
In addition to the blistering heat, climate experts also warn of dangerous increases in humidity or humidity.
“There are two causes of climate change: temperature and humidity,” V “Ram” Ramanathan, a climate scientist at the Scripps Institution of Oceanography at the University of California San Diego and Cornell University, told the Associated Press.
Humidity, combined with the temperature on the thermometer, creates the “apparent temperature,” or what it feels like outside. In addition, high heat and humidity can increase “wet bulb” temperature — a measure of how much the body can cool itself down.
Scientists have warned that wet bulb temperatures above 95F (35C) are “unsurvivable” for people experiencing it for at least six hours. While such high wet-bulb temperatures are still rare, they are becoming more common around the world, according to NASA.
Large parts of the US are facing a warmer-than-average August, according to the monthly forecast from the National Weather Service’s Climate Prediction Center.
Blister temperatures returned to the center of the US this week, with temperatures hovering around or above 100F (38C) from Texas to South Dakota.
Much of the central US and the northeast has a heat rating, as high temperatures combined with humidity make it feel above 90F (32C) or 100F through the northeast, southeast, and central plains. Conditions in southwestern Iowa could reach 45 degrees Celsius on Saturday as heat and humidity seep through.
On Thursday, both Boston, Massachusetts and Hartford, Connecticut broke their daily temperature records as the mercury reached 98F (37C) and 96F (36C), respectively.