More severe heat waves will broil the U.S.
Climate change will become the lead driver of extreme heat waves in the western U.S. as soon as the late 2020s, a new study has found. Using historical data and climate models, researchers projected future temperature patterns under current “business as usual” carbon emissions, reports ScienceDaily.com. Their goal was to establish at what point human-induced global warming will surpass natural climate variability as the most likely cause of heat waves, defined as three or more days of record-high temperatures. The researchers concluded that this threshold would be crossed in California, Nevada, and the drier parts of Oregon, Utah, Arizona, and Idaho in 2028. They predicted it would happen in the Great Lakes region in 2037; in the Northern Great Plains in 2056; and the Southern Plains in 2074. Overall, the researchers calculated that half of the extreme heat waves projected to take place this century wouldn’t happen without anthropogenic global warming. The top cause of weather-related deaths in the U.S., heat waves have become more frequent and intense in recent decades, as the world has warmed. Study author Hosmay Lopez, a meteorologist at the National Oceanic and Atmospheric Administration, says the findings are “a significant advancement in the scientific understanding of future projections of heat waves.” ■