What makes a ‘heat dome’ and what does it mean?
These unbearably hot and humid summer months, which put millions of people around the world at risk, are typically made possible by the well-known phenomenon of: heat domes.
Heat domes can make already high temperatures even more extreme and prolonged; As the planet warms, the severity of these temperatures becomes worse and more frequent.
Here’s what you need to know.
What makes up a heat dome and what does it do?
Experts say thermal domes are actually high-pressure systems suspended above an area that traps heat and moisture.
They are caused by the northward flow of warm air. This system allows air to descend, pressure to increase and temperatures to rise.
“The concept of a heat dome really means that the air in this region is very hot, and we know that warm air is expanding,” said climate scientist Jennifer Francis of the Woodwell Climate Research Center. “This basically means that the atmospheric layers are also bulging upward.”
Put simply, heat domes cause heat waves, experts say.
How did the heat affect the world this year?
Heat affected various parts of the world early 2026.
Registered in the continental United States March was the hottest month on record in 132 years. record-breaking extremes first in the Southwest, then throughout the rest of the country. Heat burned the French Open And Parched regions of India In May. There have been extreme temperatures since Memorable at the World Cup Across the USA, Canada and Mexico.
Since mid-June, Europe has experienced unseasonably high temperatures of around 100,000. 40 degrees Celsius (104 degrees Fahrenheit) in many places due to the heat dome.
Now, most Eastern US expected to be hit We’re facing an extended heat wave in the coming days, and much of the Southwest is already experiencing temperatures around 100 degrees Fahrenheit (38 Celsius) this week, and those temperatures could reach other locations by the July 4th holiday.
What is the role of climate change?
Science shows that as the planet warms (as a result of humans burning coal, oil, and gas), heat waves are getting worse, lasting longer, and becoming more frequent.
“Heat waves like this are directly linked to the climate crisis and climate change,” Francis said, “and this is because we have been burning fossil fuels for so long, cutting down forests and increasing the concentration of heat-trapping gases in the atmosphere.
“These types of heat waves, droughts and associated fires are on the rise, just as we would expect in a warming world,” he said.
How can I stay safe?
Experts say that people should not remain dehydrated due to sweltering heat and humidity. Heat domes can make it difficult to completely escape high temperatures at night, so it’s important to find ways to stay cool during the day and evening hours.
Avoid exercising outdoors in the heat of the day and find shade or access to air conditioning if possible. Some cities provide resources and cooling centers to provide relief.
Cooling off near pools or bodies of water can also help.
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Alexa St. John is a climate correspondent for the Associated Press. Follow him on X: @alexa_stjohn. Reach him at ast.john@ap.org.
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