Fifteen years of grading warming’s impact on the Arctic has made one thing abundantly clear: Climate change has drastically altered the Arctic in that short time period.
Breaking unfortunate records is “like whack-a-mole,” says Jackie Richter-Menge, a climate scientist at the University of Alaska Fairbanks and an editor of the 2020 Arctic Report Card, released December 8 at the virtual meeting of the American Geophysical Union. From sea ice lows to temperature highs, records keep popping up all over the place. For instance, in June, a record-high 38° Celsius (100.4° Fahrenheit) temperature was recorded in the Arctic Circle (SN:6/23/20). And in 2018, winter ice on the Bering Sea shrank to a 5,500 year low (SN:9/3/20).
“But quite honestly, the biggest headline is the persistence and robustness of the warming,” Richter-Menge says. In 2007, only a year after the first Arctic Report Card, summer sea ice reached a record low, shrinking to an area 1.6 million square kilometers smaller than the previous year. Then, only five years later, the report card noted a new low, 18 percent below 2007. In 2020, sea ice didn’t set a record but not for lack of trying: It still was the second lowest on record in the last 42 years.
“The transformation of the Arctic to a warmer, less frozen and biologically changed region is well under way,” the report concludes. And it’s changing faster than expected when researchers launched the report card in 2006. The annual average air temperature in the Arctic is rising two to three times faster than the rest of the globe, Richter-Menge says. Over the last 20 years, it’s warmed at a rate of 0.77 degrees C per decade, compared with the global average of 0.29 degrees C per decade.