El Niño Predicted to Supercharge Record Global Heating in 2024

The current El Niño event — which has been impacting global temperatures and weather since July of last year — is predicted to continue to drive record heat in 2024, according to a new modeling analysis by an international team of researchers.

According to the study, several areas worldwide are likely to see record-setting average surface air temperatures (SAT) as a result of El Niño until June 2024.

“The likelihood of global mean SAT exceeding historical records, calculated from July 2023 to June 2024, is estimated at 90%,” the researchers wrote in the study. “Regions particularly susceptible to recording record-high SAT include coastal and adjacent areas in Asia such as the Bay of Bengal and the South China Sea, as well as Alaska, the Caribbean Sea, and the Amazon. This impending warmth heightens the risk of year-round marine heatwaves and escalates the threat of wildfires and other negative consequences in Alaska and the Amazon basin, necessitating strategic mitigation measures to minimize potential worst-case impacts.”

The El Niño-Southern Oscillation — a main driver of global climate variability — is concentrated in the tropical Pacific Ocean, Nature Publishing Group said. The warming associated with El Niño and the cooling of its partner phase La Niña both affect weather. During El Niño, heat is released into the atmosphere, bringing a faster rise in global mean surface temperatures (GMST). Even a small uptick in GMST has been associated with marked increases in SAT during periods of extreme heat.

“Changes in global surface air temperature (SAT) are influenced by external forcing (e.g., greenhouse gases) and internal climate variations,” the research team wrote. “[D]uring El Niño events, the ocean releases heat to the atmosphere, primarily due to increased air-sea heat fluxes driven by elevated sea surface temperatures (SST). Accordingly, during El Niño phase, enhanced atmospheric heating in the tropics accelerates a rise in global annual mean surface temperature (GMST), contributing to record-breaking warming (e.g., 2015–2016).”

The researchers modeled the current El Niño event’s effects on the regional fluctuation in average SAT from the 1951 to 1980 average and July of 2023 to June of 2024. The peak of El Niño is usually from November to January.

The research team found that a moderate El Niño would bring record average SAT to the Philippines and the Bay of Bengal, while a strong El Niño event would lead to record mean SAT in the South China Sea, the Caribbean Sea and areas of Alaska and the Amazon.

The study, “Enhanced risk of record-breaking regional temperatures during the 2023–24 El Niño,” was published in the journal Scientific Reports.

The scientists also used modeling to look at El Niño’s effects on GMST during the same period, Nature Publishing Group said. They discovered that a moderate or stronger event would lead to a 90 percent likelihood of record GMST. Under the moderate scenario, they estimated the GMST for 2023 to 2024 to be from 1.03 to 1.10 degrees Celsius above the average for 1951 to 1980. Their GMST estimate for the strong El Niño scenario was a GMST of 1.06 to 1.20 degrees Celsius above the benchmark.

The team warned that record mean temperatures would likely make it difficult for regions to cope with the effects of excess heat.

The scientists called attention to the fact that elevated SAT can result in a major rise in the probability of extreme climate events like tropical cyclones, heat waves and wildfires, especially in coastal and oceanic areas where the ocean’s increased heat capacity leads to persistent and extended climate conditions.

“This study uses observed temperature records, and what we know about El Niño and other effects on the rest of the globe, to infer what might happen in 2024,” said Adam Scaife, head of long range prediction with the UK’s Met Office, as The Guardian reported. “Some regions, Africa and Greenland for example, have poor historical data coverage and are hard to assess with these methods, but they are highlighted as regions with prominent levels of excess heat this year in climate model forecasts.”