As the climate crisis raises average temperatures around the world, new data has revealed that extreme heat is an increasingly urgent problem, surpassing other weather events in its deadly nature.
Floods, hurricanes, tornadoes and even freezing conditions are all dwarfed by the total number of deaths that occur each year from extreme heat, according to findings from the US National Weather Service.
The government agency found that 190 people died from heat in 2021, well above the ten-year average of 135. The next deadliest weather event was floods, which killed 146 in the same year and 98 on average over the past decade.
Other hazardous weather conditions included rip currents, cold weather and tornadoes, all of which were significantly deadlier in 2021 than the 10-year average.
Episodes of extreme heat, evident in this summer’s record highs around the world, are likely to be both more frequent and more severe due to the climate crisis.
And other extreme weather events, like floods, hurricanes and wildfires, are fueled by rising global temperatures caused by greenhouse gas emissions largely from the burning of fossil fuels.
In July, nearly every region of the United States was hit by relentless heat waves, placing more than 150 million people under heat warnings and advisories. More than 350 new daily high temperature records have been tracked, according to the National Oceanic and Atmospheric Administration.
Abnormally high temperatures in the Pacific Northwest last week led to at least 20 potential heat-related deaths.
But that has nothing to do with last year’s “heat dome” event in the Pacific Northwest, which killed more than 800 people in the United States and Canada. The heatwave, where the normally temperate region saw the mercury reach well above 100 degrees Fahrenheit (38 degrees Celsius), was deemed 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 minor cases, the heat can lead to fainting or cramping – but in severe cases, the extreme heat can cause heat stroke as the body quickly reaches temperatures over 100 F (38 C).
Heat stroke can be fatal without emergency medical treatment. Some of the people most vulnerable to heat-related illnesses are the elderly, young children, pregnant women, and people with underlying health conditions like heart disease.
Also, the heat may affect some communities more than others. Outdoor workers, the poorest people and the homeless are all at greater risk of heat-related health problems, notes the World Health Organization (WHO).
A 2021 study found that in the United States, poorer neighborhoods and neighborhoods with more blacks, Hispanics, and Asians were generally warmer than wealthier, whiter neighborhoods, which may impose additional heat loads to these communities.
Beyond the scorching heat, climate experts also warn of a dangerous increase in air humidity or humidity.
“There are two drivers of climate change: temperature and humidity,” said V “Ram” Ramanathan, a climatologist at the Scripps Institution of Oceanography at the University of California, San Diego and Cornell University, at the Associated Press.
The humidity, combined with the temperature on the thermometer, creates the “apparent temperature”, or what it feels like outside. Additionally, high heat and humidity can raise the “wet bulb” temperature – a measure of the body’s ability to cool itself.
Wet-bulb temperatures above 95°F (35°C) are “unsurvivable” for humans who experience them for at least six hours, scientists have warned. While instances of wet bulb temperatures this high are still rare, they are becoming more common around the world, according to NASA.
Large parts of the United States face a warmer than average August, according to the monthly outlook from the National Weather Service’s Climate Prediction Center.
Searing temperatures returned to the central United States this week, with temperatures hovering around or above 100F (38C) from Texas to South Dakota.
Much of the central and northeastern United States is under a heat advisory as high temperatures combined with humidity will cause it to feel above 90 F (32 C) or 100 F in the northeast, southeast and central plains. Conditions in southwestern Iowa could reach 113F (45C) on Saturday as heat and humidity spread.
Boston, Massachusetts and Hartford, Connecticut broke their daily temperature records on Thursday as the mercury hit 98F (37C) and 96F (36C), respectively.