News•March 19, 2014

A Cold U.S. Winter for Sure, but 8th Warmest Globally

Despite the frigid temperatures that kept those in the eastern United States shivering all winter, the period from December 2013 to February 2014 was the 8th warmest on record globally, the U.S. National Climatic Data Center reported Wednesday. That warmth early in the year could set the stage for another record or near-record warm year, one NCDC scientist said.

And February, which was the 21st warmest globally since record keeping began in 1880, was the 348th consecutive month where temperatures were higher than the global average; the last month with below-average temperatures was exactly 29 years ago, in February 1985, when Ronald Reagan was just beginning his second term as president.

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The high ranking may come as a surprise to those who spent the winter digging out from seemingly never-ending snow storms and blasts of Arctic air courtesy of a wonky jet stream that tipped the infamous polar vortex toward the eastern U.S. and sent cold Canadian air washing over the region. (In fact, parts of Ontario, Canada, experienced a February that ranked among their top 10 coldest in the record books.)

But those chilly areas were more than offset by the warmer-than-average temperatures that most of the world’s land areas saw, which were also caused by the way the jet stream pushed areas of high and low pressure across the Northern Hemisphere.

“Large north-south gradients in the jet stream contributed to these extreme differences, with warmer-than-average temperature below the ridges and cooler-than-average temperatures above the troughs due to cold polar air streaming into these regions,” Jessica Blunden, a climate scientist with ERT, Inc., at the NCDC told Climate Central in an email. “Additionally, the majority of land and ocean surfaces around the world were above their average temperatures. When combining these factors, we can see where the extreme cold was more than offset by warmth.”

The average global temperature for February was 0.74°F above the 20th century average for the month (53.9°F), while the entire December-to-February period was 1.57°F above the 20th century average, the NCDC reported.

In particular, Scandinavia and the Russian Far East saw extremely warm winters, with temperatures in Finland trending 11°–14° F above normal, making it the second-warmest February there in the past 115 years, the NCDC report said.

Winter in the U.S., on the other hand, was the 34th coldest in the past 119 years – chilly, but not enough to come close to breaking into the top 10.

The ranking of the 2013-2014 winter (summer in the Southern Hemisphere) as the 8th warmest surpasses that of 2012-2013, which was the 12th warmest. Since 2013 turned out to be the 4th warmest year on record globally, “it is definitely possible that we could end up record or close to record warm for the globe in 2014, especially if El Niño conditions develop in the summer or fall as many scientists and agencies are predicting,” Blunden said.

The National Oceanic and Atmospheric Administration issued an El Niño Watch earlier this month, saying there was more than a 50 percent chance of the climate phenomenon developing. The warmer-than-average waters in the tropical Pacific that characterize an El Niño influence weather patterns across the globe and El Niño years are typically warmer than average.