Impact of Climate Change on Heatwaves and Extreme Weather

More than 80 million people are currently experiencing an Extreme Heat Warning or Heat Advisory this week, according to the National Weather Service. The Weather Prediction Center describes the heat dome as a “steamy air-mass even by mid-to-late August standards.” The dangerous, record-breaking heat continues to affect the South-Central U.S. and will spread into the Southwest by mid-week, with daytime temperatures reaching triple digits.

The desert Southwest, including Arizona and New Mexico, could also face new heat records, as stated by the National Weather Service. Temperatures exceeding 100 degrees Fahrenheit are expected to stay in the Southern Plains and Lower Mississippi Valley through mid-week. The Southwest will keep warming until week’s end, with highs possibly reaching 110 degrees or more. Nights offer little relief, remaining warm, which heightens the risk of heat-related illnesses.

“For garden variety heat waves — like the hottest day of the year, or the hottest day every 10 years — climate change has increased the temperature by 3 to 5 degrees Fahrenheit,” noted Michael Wehner, a senior scientist at Lawrence Berkeley National Laboratory.

As the senior climate editor at NPR, I provide guidance on how to report the influence of climate change during extreme weather events. Currently, vast U.S. regions face threats from severe heat, and additional context on climate change’s role is necessary.

What’s Happening?

This heat wave will continue to affect the Southern Plains and the Lower Mississippi Valley, keeping temperatures above 100 degrees Fahrenheit. Furthermore, the Southwest will see gradual warming, with highs reaching 110 degrees or more by the end of the week. The high temperatures and warm nights increase the risk of heat-related illnesses.

Understanding Climate Change’s Role

The connection between climate change and heat waves is established in scientific research. Even so, distinguishing credible information from falsehoods can be difficult due to the volume of data available. Human-induced climate change is making heat waves longer and more severe both in the U.S. and globally. It leads to dangerously high temperatures more frequently. Since the 1980s, the number of U.S. heat waves has doubled. Heat records are becoming common due to global warming.

Without human-caused climate change, some of the most intense heat waves would be unimaginable. For instance, June’s extreme heat in Europe, according to scientists at the World Weather Attribution group, would not occur without human influence on the climate.

Health Concerns Related to Heat

During extreme heat, the heat index becomes crucial. It represents how hot it feels when humidity combines with air temperature, which is estimated to be between 105-115 degrees in parts of southern Arizona, Texas, Louisiana, and Florida. Heat-related deaths, which often go undercounted, are more deadly than hurricanes, wildfires, and floods combined. Humidity prevents sweat from evaporating, leaving the body unable to cool down effectively, posing a significant threat.

Your Turn

Extreme weather isn’t new, but climate change amplifies these events in frequency and intensity. NPR’s reporters strive to help communities grasp the extensive impact and understand the ongoing efforts to mitigate them. We seek your input. What questions about climate change and extreme weather do you have? Share with us to influence our future reporting.

Sadie Babits, senior supervising climate editor for NPR and author of “Hot Takes: Every Journalist’s Guide to Covering Climate Change,” manages these inquiries and articles.