by February is on track to break all-time heat records, according to meteorologists, as man-made global warming and the natural El Niño climate pattern drive temperatures on land and oceans around the world.
A little more than halfway into the shortest month of the year, the warming spike has become so clear that climate charts are entering new territory, especially for sea surface temperatures that have risen and accelerated to to the point where expert observers are struggling to explain how change is happening.
“The planet is warming at an accelerating rate. There are rapid increases in sea temperatures in the ocean, the largest heat reservoir in the climate,” said Dr Joel Hirschi, associate head of marine systems modeling at the UK’s National Oceanographic Centre. “The amplitude at which previous sea surface temperature records were broken in 2023 and now in 2024 exceeds expectations, although understanding why is the subject of ongoing research.”
Humanity is on track to experience the warmest February in recorded history, following records for January, December, November, October, September, August, July, June and May, according to Berkeley Earth scientist Zeke Hausfather.
He said the rise in recent weeks was on track for 2C of warming above pre-industrial levels, although this should be the short peak of El Niño if it follows the path of previous years and starts to cool in the months ahead.
That’s usually good news if La Niña continues to drop temperatures, but Hausfather said the climate’s behavior was more erratic and harder to predict. “[Last year] expectations are so skewed that it’s hard to have as much confidence in the approaches we’ve used to make these predictions in the past,” he said. “I would say that February 2024 is an odd choice to beat the previous record set in 2016, but it is not a foregone conclusion at this point as weather models indicated that global temperatures will drop again in the coming weeks. So while I think these extreme temperatures provide some evidence of an acceleration in the rate of warming in recent years – as climate models expect CO.2 emissions don’t fall but aerosols do – it’s not necessarily worse than we thought.”
The first half of February surprised weather watchers. Maximiliano Herrera, who blogs on Temperature Extremes Around the World, describing the rise of thousands of meteorological station heat records as “insane”, “absolute madness” and “rewriting climate history”. What surprised him was not just the number of records but the extent to which many of them surpassed anything that had gone before.
He said Morocco saw 12 weather stations register above 33.9C, which was not only a national record for the hottest winter day, but also more than 5C above the average for July. The northern Chinese city of Harbin had to close its winter ice festival as temperatures soared above freezing for an unprecedented three days this month.
Over the past week, monthly heat records have been registered at monitoring stations as far apart as South Africa, Saudi Arabia, Thailand, Indonesia, Kazakhstan, Colombia, Japan, North Korea, the Maldives and Belize. .
In the first half of this month, Herrera said that 140 countries broke monthly heat records, which was similar to the last figures of the hottest six months on record of 2023 and more than three times in any month before 2023.
The warming of the ocean surface always surprises experienced observers and increases the prospect of major storms later in the year. The hurricane specialist Michael Lowry tweeted that sea surface temperatures across the main developed Atlantic region, where most hurricanes are category 3 or stronger in the United States, “are as warm today in mid-February as they were in mid-July normal. Unbelievable.”
Global sea surface temperatures are in “uncharted territory” according to Hirschi, who expects March to break last August’s record by 0.1C to 0.2C. March is usually the warmest time of year for the oceans because it is late summer in the southern hemisphere, where most of the world’s great seas are located.
The temperature spikes were expected, although their amplitude came as a surprise. Climatologists are studying how to attribute weight to the various causes behind such anomalies.
A strong El Niño has pushed temperatures higher, but Francesca Guglielmo, Copernicus senior scientist, noted that this was just one of several warming factors working together. Every additional tonne of carbon dioxide emitted by mankind increases the pressure on the oceans. In some areas, the anomalous heat has also been reinforced by weak trade winds, a lethargic jet stream, fluctuations in the North Atlantic circulation and reductions in aerosol pollution, which exposes more of the ocean to the sun.
Katharine Hayhoe, the Nature Conservancy’s chief scientist, said the uncertainty about the interplay of different factors is a reminder that we do not fully understand all aspects of how the complex Earth system is responding to unprecedented radiation forcing. “This is happening at a much faster rate than has ever been documented in the past,” she said. “If anything, we are much more likely to underestimate the impact of these changes on human society than to appreciate them.”
El Niño is now weakening, which should reduce temperatures in the equatorial Pacific Ocean from late spring to early summer. If the North Atlantic remains warm at that time, this could herald intense hurricane activity, Hirschi warned.
Such risks will increase every year unless human carbon emissions are reduced and forest clearance is reversed. “It appears that slowing down, stopping or reversing the warming trajectory we’re on would change the course of a massive tanker. The results are not immediate but the sooner we take action, the easier it is for us to avoid trouble,” he said.
