Heat wave

Summer 2024 was officially the Northern Hemisphere’s hottest on record. In the United States, fierce heat waves seemed to hit somewhere almost every day. Phoenix reached 100 degrees for more than 100 days straight. The 2024 Olympic Games started in the midst of a long-running heat wave in Europe that included the three hottest days on record globally, July 21-23. August was Earth’s hottest month in the National Oceanic and Atmospheric Administration’s 175-year record. Overall, the global average temperature was 2.74 degrees Fahrenheit (1.52 degrees Celsius) above the 20th-century average. That might seem small, but temperature increases associated with human-induced climate change do not manifest as small, even increases everywhere on the planet. Rather, they result in more frequent and severe episodes of heat waves, as the world saw in 2024. The most severe and persistent heat waves are often associated with an atmospheric pattern called a heat dome. As a...

Millions of Americans have been sweltering through heat waves in recent weeks, and U.S. forecasters warn of a hot summer ahead. Globally, 2023 saw the warmest June on record, according to the European Union’s climate change service. That heat continued into July, with some of the hottest global daily temperatures on satellite record, and possibly the hottest. For people who struggle to afford air conditioning, the rising need for cooling is a growing crisis. An alarming number of Americans risk losing access to utility services because they can’t pay their bills. Energy utility providers shut off electricity to at least 3 million customers in 2022 who had missed a bill payment. Over 30% of these disconnections happened in the three summer months, during a year that was the fifth hottest on record. In some cases, the loss of service lasted for just a few hours. But in others, people went without electricity for days or weeks while scrambling to find enough money...

Ocean temperatures have been off the charts since mid-March 2023, with the highest average levels in 40 years of satellite monitoring, and the impact is breaking through in disruptive ways around the world. The sea of Japan is more than 7 degrees Fahrenheit (4 degrees Celsius) warmer than average. The Indian monsoon, closely tied to conditions in the warm Indian Ocean, has been well below its expected strength. Spain, France, England and the whole Scandinavian Peninsula are also seeing rainfall far below normal, likely connected to an extraordinary marine heat wave in the eastern North Atlantic. Sea surface temperatures there have been 1.8 to 5 F (1 to 3 C) above average from the coast of Africa all the way to Iceland. So, what’s going on? Sea surface temperatures are running well above the average since satellite monitoring began. The thick black line is 2023. The orange line is 2022. The 1982-2011 average is the middle dashed li...

It’s coming. Winds are weakening along the equatorial Pacific Ocean. Heat is building beneath the ocean surface. By July, most forecast models agree that the climate system’s biggest player – El Niño – will return for the first time in nearly four years. El Niño is one side of the climatic coin called the El Niño-Southern Oscillation, or ENSO. It’s the heads to La Niña’s tails. During El Niño, a swath of ocean stretching 6,000 miles (about 10,000 kilometers) westward off the coast of Ecuador warms for months on end, typically by 2 to 4 degrees Fahrenheit (about 1 to 2 degrees Celsius). A few degrees may not seem like much, but in that part of the world, it’s more than enough to completely reorganize wind, rainfall and temperature patterns all over the planet. Marine heat waves can trigger coral bleaching. Alexis Rosenfeld/Getty Images...

Home runs are exhilarating – those lofting moments when everyone looks skyward, baseball players and fans alike, anxiously awaiting the outcome: run or out, win or loss, elation or despair. Over the past several Major League Baseball seasons, home run numbers have climbed dramatically, including Aaron Judge’s record-breaking 62 homers for the New York Yankees in 2022. Baseball analysts have pointed to many different factors for this surge, from changes in baseball construction to advances in game analytics. Our study, published April 7, 2023, offers solid evidence for another cause – rising global temperatures. What we learned from 100,000 baseball games The physics tell a simple and compelling story: Warm air is less dense than cool air. As air heats up and molecules move faster, the air expands, leaving more space between molecules. As a result, a batted ball should fly farther on a warmer day than it would on a cooler day owing to less air resistance. Th...