Arctic warming has been greatly underestimated

A new study from the University of Copenhagen has revealed that the Arctic is warming at an even higher rate than expected. The researchers report that temperatures in the Arctic Ocean between Canada, Russia, and Europe are rising faster than climate models have predicted.

Average temperatures have increased by one degree per decade over the last 40 years, according to the study. In the Barents Sea and around Norway’s Svalbard archipelago, temperatures have risen by 1.5 degrees per decade.

“Our analyses of Arctic Ocean conditions demonstrate that we have been clearly underestimating the rate of temperature increases in the atmosphere nearest to the sea level, which has ultimately caused sea ice to disappear faster than we had anticipated,” explained study co-author Professor Jens Hesselbjerg Christensen.

The research team compared current Arctic warming with historical climate fluctuations, such as those which occurred in Greenland during the ice age between 120,000 and 11,000 years ago.

“The abrupt rise in temperature now being experienced in the Arctic has only been observed during the last ice age. During that time, analyses of ice cores revealed that temperatures over the Greenland Ice Sheet increased several times, between 10 to 12 degrees, over a 40 to 100-year period,” said Professor Hesselbjerg Christensen.

He noted that the significance of the steep rise in temperature is yet to be fully appreciated, and that much more focus on Arctic warming and climate change mitigation is needed. 

Prior to this study, climate models have predicted that Arctic temperatures would rise in a slow and stable manner, but this fails to account for abrupt shifts. The current research indicates that abrupt changes must be considered.

“We have looked at the climate models analyzed and assessed by the UN Climate Panel. Only those models based on the worst-case scenario, with the highest carbon dioxide emissions, come close to what our temperature measurements show over the past 40 years, from 1979 to today,” said Professor Christensen.

“Changes are occurring so rapidly during the summer months that sea ice is likely to disappear faster than most climate models have ever predicted. We must continue to closely monitor temperature changes and incorporate the right climate processes into these models.”

“Thus, successfully implementing the necessary reductions in greenhouse gas emissions to meet the Paris Agreement is essential in order to ensure a sea-ice packed Arctic year-round.”

The study is published in the journal Nature Climate Change.

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By Chrissy Sexton, Earth.com Staff Writer