Thanks to unrelenting human-caused global warming, and with a little push from El Niño, last month continued 2023’s heat streak, coming in as the warmest January on record.
Three independent analyses have come to this conclusion, the most recent released by NOAA on Feb. 14. According to the agency, January’s global surface air temperature was 1.27 degrees C (2.29 degrees F) above the 20th-century average. That’s very close to an assessment released by NASA a week prior.
January’s unusual global warmth follows on from 2023’s record-smashing temperatures. Last year turned out to be the warmest in records dating back to the 1800s. For details about what contributed to that extraordinary warmth, including the role of El Niño in nudging temperatures up, check out a two-part series I wrote on the subject here and here.
So far this year, sea surface temperatures have been running at record-high levels. (Credit: Climate Reanalyzer. Annotations by Tom Yulsman)
Unfortunately, another heat streak continued as well: sizzling seas. January marked the 10th straight month of record-setting sea surface temperatures.
What’s more, the global average for the month was almost as high as the record-setting sea surface temperatures of August of 2023. And now, February is eclipsing August’s highs, taking us further into uncharted territory.
The ongoing El Niño has played a role in this. But sea surface temperatures continue to run high not just in El Niño’s home turf in the equatorial Pacific, but also in broad swaths all around globe. That shouldn’t be surprising, given that 90 percent of the warmth accumulating in the climate is absorbed by the oceans.
Unfortunately, what goes into the oceans doesn’t all stay there. “The exceptional warmth observed in the oceans is a key contributor to the record global surface air temperature for January,” according to a recent analysis from the European Union’s Copernicus Climate Change Service. That’s also true of 2023’s warmth.
Overall, recent global warming has been significant enough for the world to at least temporarily pass a significant milestone. For the 12 months ending in January, the average global temperature was 1.52 degrees C (2.74 degrees F) above the 1850 to 1900 pre-industrial average, according to the Copernicus analysis. That’s a smidge higher than the 1.5 degrees C threshold that 194 nations and the European Union agreed to try to avoid under the Paris Agreement.
It must be stressed that while this is symbolically significant, it doesn’t mean climatic doom is nigh. Exceeding 1.5 degree C of warming won’t trigger the collapse of the Greenland and Antarctic ice caps, or a dangerous scrambling of jet streams and ocean circulation patterns. And limiting warming to that level is a political goal, intended to help countries craft policies for avoiding climate impacts that will become increasingly challenging to adapt to with every tenth of degree of extra warming.
Crossing the threshold over the past 12 months also doesn’t mean that the Paris Agreement is a lost cause. That’s because it is about long-term warming — meaning warming over the course of years, not months. (As defined by the Intergovernmental Panel on Climate Change, long-term is 20 to 30 years.)
In fact, as El Niño wanes, we’ll likely dip back below the 1.5 degrees C threshold for a time. To keep it there will require much more aggressive action on reducing emissions of climate-warming carbon dioxide and other greenhouse gases. Although many experts regard this as a long shot now, this is still doable.
