February is on track to break a record number of heat records, meteorologists say, as man-made global warming and the natural El Niño climate pattern raise temperatures on land and in the oceans around the world.
Just over halfway through the shortest month of the year, the warming peak has become so pronounced that climate maps are breaking new ground, especially for sea surface temperatures that have persisted and accelerated to the point where expert observers are struggling to explain how the change is happening.
“The planet is warming faster and faster. We are seeing rapid temperature increases in the ocean, the climate’s largest heat sink,” said Dr Joel Hirschi, head of marine systems modeling at the UK’s National Oceanography Centre. “The magnitude by which previous sea surface temperature records were exceeded in 2023 and now in 2024 exceeds expectations, but understanding why this is the case is the subject of ongoing research.”
Humanity is on track to experience the warmest February on record, following record-breaking January, December, November, October, September, August, July, June and May, according to the Berkeley Earth Scientist Zeke Hausvader.
He said the increase in recent weeks was on track for a warming of 2 degrees above pre-industrial levels, although this should be the short peak impact of El Niño if it follows the path of previous years and starts to decline in the coming months to cool.
Normally that would be good news if a temperature-lowering La Niña follows, but Hausfather said the climate’s behavior has become more erratic and harder to predict. “[Last year] has defied expectations to such an extent that it is difficult to have so much confidence in the approaches we have used in the past to make these predictions,” he said. “I would say that February 2024 is an absolute favorite to beat the previous record of 2016, but that is by no means a foregone conclusion at this point as weather models suggests that Global temperatures will drop again in the coming week. So while I think these extreme temperatures provide some evidence of an acceleration of warming in recent years – as climate models expect if CO2 Emissions are not decreasing, but aerosols are. It’s not necessarily worse than we thought.”
The first half of February shocked weather observers. Maximiliano Herrera, who blogs Extreme temperatures around the world, described the spate of thousands of heat records from meteorological stations as “insane,” “total madness” and “rewritten climate history.” What amazed him was not just the number of records, but the extent to which many of them surpassed anything that had gone before.
He said that in Morocco, 12 weather stations had recorded temperatures of more than 33.9 degrees Celsius, which was not only a national record for the hottest winter day, but also more than 5 degrees above the average for July. The northern Chinese city of Harbin had to close its winter ice festival after temperatures rose above freezing for three days this month.
Over the past week, monitoring stations as far apart as South Africa, Saudi Arabia, Thailand, Indonesia, Kazakhstan, Colombia, Japan, North Korea, the Maldives and Belize have recorded monthly heat records.
In the first half of this month, 140 countries broke monthly heat records, according to Herrera, which was comparable to the final figures of the last six record warmest months of 2023 and more than three times every month before 2023.
The ocean’s surface heat continues to surprise seasoned observers and raises the prospect of intense storms later in the year. The hurricane specialist Michael Lowry tweeted that sea surface temperatures in the key developing region of the Atlantic Ocean, where most Category 3 or stronger hurricanes form in the U.S., “are as warm today in mid-February as they normally are in mid-July. Unbelievable.”
Global sea surface temperatures are in “uncharted territory” according to Hirschi, who expects March to break last August’s record by 0.1 to 0.2 degrees Celsius. March is typically the warmest time of year for the oceans because it is late summer in the Southern Hemisphere, where most of the world’s major seas are found.
The temperature spikes were expected, although their magnitude came as a surprise. Climatologists are now studying how to give weight to the different causes behind such anomalies.
A strong El Niño has caused temperatures to rise, but Francesca Guglielmo, a senior scientist at Copernicus, noted that this was just one of many heating factors working in combination. Every additional ton of carbon dioxide emitted by humanity increases pressure on the oceans. In some areas, the abnormal heat has also been amplified by weak trade winds, a lethargic jet stream, fluctuations in the North Atlantic circulation and reductions in aerosol pollution, exposing more of the ocean to the sun.
Katharine Hayhoe, chief scientist at The Nature Conservancy, said the uncertainty about how the different factors interact reminded us that we do not fully understand every aspect of how the complex Earth system responds to unprecedented radiative forcing. “This is happening much faster than has ever been documented,” she says. “We are far more likely to underestimate the impact of these changes on human society than to overestimate them.”
El Niño is now weakening, which should lower temperatures in the equatorial Pacific from late spring or early summer. If the North Atlantic remains warm at that time, it could be a harbinger of intense hurricane activity, Hirschi warned.
Such risks will increase every year unless human CO2 emissions are reduced and deforestation is reversed. “Slowing, stopping or reversing the warming trajectory we are on is akin to changing the course of a supertanker. The results are not immediate, but the sooner we take action, the easier it will be for us to prevent problems,” he said.