As climate change begins to cause more days of intense heat, certain parts of the U.S. face more danger than others.
As climate change begins to cause more days of intense heat, certain parts of the U.S. face more danger than others.
The world recently experienced the hottest days ever in July, three days in a row during which the average world temperature reached 62.6 degrees. That makes them the hottest days since records started being kept in 1940, and likely before that, according to the European Union’s Copernicus Climate Change Service.
What’s more, experts warn that the planet could be entering a multi-year cycle of increasing, intense heat, driven in part by the El Niño, a cyclical weather pattern.
While people can take steps to reduce their own carbon footprint, the increasing instances of extreme weather have led some to consider moving to areas less susceptible to weather events, including frequent days of intense heat.
People can consider all types of different weather to avoid – flooding if you live near the coast or a river, for example, or hurricanes, tornadoes, and wildfires. The following considers only intense heat, one of the biggest (and most frequent) impacts of a warming planet.
Climate change contributes to intense heat through various mechanisms.
The burning of fossil fuels like coal, oil, and gas has led to a large increase in the amount of greenhouse gases (such as carbon dioxide) in the Earth’s atmosphere. These gasses trap heat from the sun, preventing it from escaping back into space. This “greenhouse effect” enhances the Earth’s overall temperature.
Greenhouse gas emissions lead to a rise in average global temperatures. As a result, heatwaves become more frequent, longer-lasting, and more intense. Warmer air masses are more likely to dominate, leading to prolonged periods of hot weather.
Climate change can disrupt normal atmospheric patterns and influence weather systems. It can cause changes in the jet stream, a high-altitude wind current that guides weather systems. A weakened or distorted jet stream can result in weather patterns stalling or becoming stationary, leading to extended periods of intense heat.
Climate change can trigger feedback loops that intensify heat. For example, as temperatures rise, snow and ice in polar regions melt at accelerated rates. Since ice reflects sunlight, its loss means that more solar energy is absorbed by the planet’s surface, further increasing temperatures. Also, as permafrost thaws it releases methane, a potent greenhouse gas.
Climate change increases the urban heat island effect, where cities experience higher temperatures compared to surrounding rural areas. Urban areas have large amounts of concrete and asphalt, which absorb and store heat. Rising temperatures due to climate change amplify this effect, making cities even hotter.
The Brookings Institute recently released a study that found as many as 23 million Americans live in areas where that are the most at-risk for extreme heat, based on three factors. As the institute pointed out, certain areas deal with the economic and health fallout from intense heat in much the way other places deal with hurricanes and flooding.
The report looked at three factors involved in extreme heat.
Days with high temperatures. Cities in Arizona, California, Texas, and Oklahoma led the list of metro areas that already have more than 76 days per year of temperatures over 90 degrees. About 60 million people live in these areas. They include Los Angeles, Las Vegas, Houston, Dallas, Phoenix, Oklahoma City, as well as cities further north, such as Kansas City and Richmond, Vir.
Areas with high energy costs. This is the economic fallout of intense heat. The report found that 10.5 million Americans live where their energy bills take up 6% of their monthly budget (the national average is 3%). Metros in the Southwest and Southeast face this issue more than other parts of the country, including vast areas in Texas and Florida.
Most vulnerable population. The study also looked at areas with the most vulnerable population to extreme heat – those under the age of five and those over the age of 60. They include large sections of California, Florida, and Texas.
The report concluded that those with all three risk factors – a group of at least 23 million Americans – face the most risk from intense heat. They included the Imperial Valley in California; the area southwest of Tucson; El Paso, Texas; communities along the Texas-Mexico border, and areas of Mississippi, Alabama, Georgia, and South Carolina.
Moody’s also released a list of cities most at-risk from climate change, considering all factors, not just heat. The list includes San Francisco; Cape Coral and North Port, Florida; New York City; Long Island; Oakland, Calif.; Phoenix; Tucson, Ariz.; Wilmington, Del.; and West Palm Beach, Fla.