Recent heat waves in cities worldwide have the hallmarks of global warming, researchers said. And last month was the hottest February on record.
Winter was weirdly warm for half the world’s population, driven in many places by the burning of fossil fuels, according to an analysis of temperature data from hundreds of locations worldwide.
That aligns with the findings published late Wednesday by the European Union’s climate monitoring organization, Copernicus: The world as a whole experienced the hottest February on record, making it the ninth consecutive month of record temperatures. Even more startling, global ocean temperatures in February were at an all-time high for any time of year, according to Copernicus.
Taken together, the two sets of figures offer a portrait of an unequivocally warming world that, combined with a natural El Niño weather pattern this year, has made winter unrecognizable in some places.
The first analysis, conducted by Climate Central, an independent research group based in New Jersey, found that in several cities in North America, Europe and Asia, not only was winter unusually warm, but climate change played a distinctly recognizable role.
Climate Central looked at anomalies in December and January temperature data in 678 cities worldwide and asked: How important are the fingerprints of climate change for these unusual temperatures? That is to say, its researchers tried to isolate the usual variability of the weather from the influence of climate change.
“There’s the temperature,” said Andrew Pershing, Climate Central’s vice-president for science, “and then there’s our ability to really detect that climate signal in the data.”