How Bad Is Warming? La Niña May Reveal
How Bad Is Warming? La Niña May Reveal - Yale E360
Cooler waters pooling in the eastern Pacific during the 2017 La Niña. NOAA
The Pacific is set to shift from its warmer El Niño phase to its cooler La Niña phase in late summer or early fall, U.S. officials say, likely bringing an end to a long stretch of unprecedented warmth.
The world has seen 13 consecutive months of record-breaking heat, according to the EU Copernicus Climate Change Service, and the last 12 of those months have measured 1.5 degrees C warmer than the preindustrial era, meaning the world has at least temporarily surpassed the temperature target set forth in the Paris Agreement.
The monthly global temperature deviation from the preindustrial average. Copernicus Climate Change Service / ECMWF
“This is more than a statistical oddity and it highlights a large and continuing shift in our climate,” said Copernicus director Carlo Buontempo. How much of a shift is not entirely certain, however, as the record heat is being driven both by warming and by El Niño. Scientists say the end of El Niño, which was pronounced done in June, will help clarify the role of climate change.
There is a 70 percent chance that La Niña takes shape between August and October, according to the U.S. National Weather Service. “As we head into La Niña now, we will see the anomalous short-term spike of the past year disappear,” University of Pennsylvania climate scientist Michael Mann told Inside Climate News. “What will remain is the steady long-term warming that will continue as long as human-generated carbon emissions continue. That’s what the focus should be on.”
It appears that the heat is already beginning to abate. “Global temperatures have finally started falling over the past few weeks,” tweeted Zeke Hausfather, a climate scientist at the research group Berkeley Earth. “July is currently on track to be the first month since June 2023 to not set a new monthly global temperature record.”
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