Marshall Shepherd provides expertise on extreme heat threats


Dr. Marshall Shepherd, director of the University of Georgia’s atmospheric sciences program, was quoted by The Guardian in a new article about the extreme heat threats facing Americans this summer.

The article reviews the looming threat of major summer heatwaves, from the arid southwest U.S. to the humid Atlantic coast. According to NOAA, the only region of the U.S. projected to have cooler temperatures this year is southwest Alaska. In addition to the potentially record-breaking temperatures, many parts of the U.S. are seeing increasingly destructive storms.

These major weather events can be partially attributed to the transition from an El Niño season to La Niña, a climatic transition that causes changes in winds and sea surface temperatures across the Pacific that affect weather patterns across both sides of the Ocean. Learn more about this phenomenon here. The other major factor in this concerning pattern is, of course, climate change.

“Record global warmth is often tied to El Niño, but as we transition to La Niña, it still looks to be a potentially record-breaking year. That clearly suggests to me that the anthropogenic signal is there,” Shepherd said. “I am also worried about the ocean temperatures, which are very warm, particularly as we approach the Atlantic hurricane season. That’s bad news, particularly since La Niña already tends to be associated with more active seasons.”

The effects of heat waves can be severe- the article cites around 1,200 heat deaths per year as a minimum, and heat-protection laws, especially for outdoor workers, are only found in a handful of states. HeatRisk, a new tool from NOAA and the CDC, provides forecasts for extreme heat.

The article ends with a stark warning from Shepherd: “Attribution studies are pretty decisive that heatwaves will continue to be more intense and frequent. These are not your grandparents’ heatwaves.”

Read the full article, published May 27, 2024, here.