Half of the world’s population is experiencing unusually warm winters due to the burning of fossil fuels in many places, according to an analysis of temperature data from hundreds of locations around the world.
That’s consistent with findings released late Wednesday by EU climate monitoring group Copernicus: The world as a whole experienced its hottest February on record, making it the ninth consecutive month of record temperatures. Even more surprising, according to Copernicus, global ocean temperatures in February were among the highest ever recorded for any time of year.
Together, the two sets of numbers paint a portrait of a decidedly warming world, which, coupled with this year’s natural El Niño weather pattern, has made winter unrecognizable in some places.
The first analysis by Climate Central, an independent research group based in New Jersey, found that not only were winters unusually warm in several cities across North America, Europe and Asia, but climate change also played a clear role.
Climate Central studied abnormal temperature data in December and January in 678 cities around the world and asked: How important is the impact of climate change on these abnormal temperatures? That is, its researchers tried to isolate usual weather changes from the effects of climate change.
“It starts with temperature,” said Andrew Pershing, Climate Central’s vice president of science, “and then we have the ability to actually detect climate signals in the data.”
Cities in the U.S. Midwest jumped off the list as they experienced unusually warm winters and the effects of climate change, caused largely by the burning of coal, oil and other fossil fuels that release greenhouse gases into the atmosphere. “It’s really great,” Dr. Pershing said. “Most of the Great Lakes are ice-free. That’s amazing.”
For example, temperatures in Minneapolis from December to February are nearly 5.6 degrees Celsius above average. Traces of climate change can be detected for 33 days, essentially one-third of the winter.
During the same three-month period, average temperatures in Tehran increased by 4.2 degrees Celsius. The effects of man-made climate change can be felt during the 68 days of winter.
Milan’s average winter temperature is about 2 degrees Celsius higher, but it sends a strong climate change signal for 55 days.
Elsewhere, despite a few distinctly hot days, average winter temperatures changed little and the climate signal was less clear.
A Climate Central report released on Wednesday concluded that 4.8 billion people around the world “experience at least one day of temperatures that would be virtually impossible without the effects of carbon pollution.”
In some parts of the world, unusually warm winter weather has been overshadowed by other crises such as war. Several cities in Ukraine are significantly warmer than usual, and there are signs of climate change there too. For example, the average temperature in Kiev this winter has increased by nearly 3 degrees Celsius, and the effects of climate change have lasted for 33 days. Likewise, in several cities in Iran, Iraq and Afghanistan.
In the tropics, average temperatures are typically much higher, so climate signals are easier to detect, although temperature increases may be smaller. For example, average temperatures in Jakarta and Kuala Lumpur increased by only 1 degree Celsius. But the effects of climate change can be detected almost throughout the three months.
It’s not just individual cities setting records this winter. Globally, February 2024 was the hottest February on record, according to the Copernicus Climate Change Service. This is 1.77 degrees Celsius higher than the average February temperature in the pre-modern pre-industrial period from 1850 to 1900.
This is the ninth consecutive month that temperature records for the month have been broken. Overall, the past 12 months were the warmest consecutive 12 months on record: 1.56 degrees Celsius above the 1850-1900 average.
“A year ago, the fact that global temperatures were 1.5 degrees Celsius above pre-industrial levels in a given month was considered abnormal,” Copernicus senior scientist Julian Nicholas said via email. Now, such a thing has Happens repeatedly.
This does not mean we have exceeded the Paris Agreement’s international target of limiting global warming to 1.5 degrees Celsius above pre-industrial temperatures. To achieve this, the Earth would need to warm by 1.5 degrees over a few years, long enough to reflect more lasting changes.
For now, in the short term, the ocean is particularly hot. Global average sea surface temperatures in February were the hottest months on record, surpassing the record set in August 2023.