We are already experiencing an El Niño climate pattern. The National Oceanic and Atmospheric Administration (NOAA) defines El Niño as a period when sea-surface temperatures in a specific region of the Pacific Ocean rise at least 0.5 °C above average. These warmer ocean temperatures trigger significant atmospheric and weather changes around the world.
El Niño could have a major impact on global temperatures. The climate pattern does not add energy to Earth’s climate system or permanently warm the entire planet. Instead, it releases heat stored in the Pacific Ocean into the atmosphere, temporarily increasing global temperatures.
However, climate change has already stored vast amounts of heat in the atmosphere and oceans. As a result, the short-term effects of El Niño can combine with long-term global warming trends, creating severe consequences, including more extreme heat, droughts, wildfires and other climate-related hazards.
This El Niño event is expected to be particularly significant. Some forecasts suggest that its peak temperature could reach more than 3.5 °C above average, potentially making it the strongest El Niño on record. The event also developed unusually quickly, with climate scientist Zeke Hausfather describing it as having “one of the earliest onsets in the observational record” in his analysis for Carbon Brief.
Although this El Niño has already begun influencing temperatures, global heat levels could continue to rise. El Niño’s effect on global temperatures typically lags behind changes in ocean conditions by several months, meaning its strongest influence may occur next year.
During several recent El Niño events, record-breaking temperatures occurred across the two calendar years affected by the climate pattern, Hausfather noted in his analysis. The most recent El Niño began in 2023 and continued into 2024, which became the hottest year on record. While there is still uncertainty about how this event will develop, it could produce another unexpected period of extreme global heat.
Given the severity of this summer’s heat wave, many regions could experience even higher temperatures next year. “El Niño will add fuel to the fire of a warming world,” United Nations Secretary-General António Guterres said in a video statement in June.
Preparing for higher temperatures should begin now. In the short term, individuals can take practical steps to protect their homes and families. If you have been putting it off, consider purchasing an air conditioner, installing solar panels and backup batteries, or improving your home’s insulation and energy efficiency.
In the long term, however, global temperatures will continue to rise unless greenhouse gas emissions decline. Humanity is still burning fossil fuels and driving climate change. As United Nations Secretary-General António Guterres said, “The only effective response is to fight climate change on par with the crisis: end dependence on fossil fuels, accelerate the transition to renewable energy, protect the most vulnerable and provide early warning systems for all.”
This article is from The Spark, MIT Technology Review‘s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.
Source: www.technologyreview.com