According to reports from BBC, Climate Progress, and The Arctic Ice Blog, sea ice scientist Professor Peter Wadhams of Cambridge University recently made a pivotal announcement on the state of Arctic sea ice. In an interview to the BBC, Wadhams noted that Arctic sea ice was ‘headed for oblivion’ within ten years and that the added heat absorbed by the darker Arctic Ocean was like adding ’20 years of CO2′ emissions.
Wadhams has been studying sea ice for decades. His research has provided pivotal insight to the Arctic environment. Back in 1996, Wadhams compiled observations from vessels, including navy submarines, operating in the Arctic to determine that sea ice volume had fallen by 40% by 1996. Today, sea ice volume has fallen 78% percent from volume observations in 1979.
Wadhams said the following to BBC:
“Thirty years ago there was typically about eight million square kilometres of ice left in the Arctic in the summer, and by 2007 that had halved, it had gone down to about four million, and this year it has gone down below that.”
“The volume of ice in the summer is only a quarter of what it was 30 years ago and that’s really the prelude to this final collapse.”
“Over that 1% of the Earth’s surface you are replacing a bright surface which reflects nearly all of the radiation falling on it with a dark surface which absorbs nearly all. The difference, the extra radiation that’s absorbed is, from our calculations, the equivalent of about 20 years of additional CO2 being added by man.”
Wadhams, a Cambridge University expert, adds his voice to a growing number of scientists and researchers pointing toward an ice free Arctic sea within the next ten years. His detailed assertion about the added warming affect, however, is new. A roughly .3-.7 watt per meter squared of additional forcing over the entire surface of the globe is a lot of new heat to add to an already stressed climate system. But most of this heat is focusing in on the fragile and sensitive Arctic.
It has been known for years that loss of reflective sea ice would add a certain degree of forcing to global climate. Now, in addition to an ever-increasing volume of CO2 absorbing more and more heat, we have lost one of our heat deflector shields. The Arctic sea ice is simply turning from white to dark blue. And this results in more heat being caught by the sun.
Throughout the Arctic summer, the sun never sets. Instead, it beams light down 24 hours a day. This light now has a growing dark surface to capture it, turning it into more heat energy. According to Wadhams, this extra forcing is equal to another 20 years of human carbon emissions.
But the concerning thing about the Arctic is that so many feedbacks are set in place to enhance warming, should a net warming occur. Wadhams has illustrated the impact of sea ice loss. But the other feedbacks include loss of reflective snow cover, loss of reflective land ice in Greenland (already losing its reflectivity), and the heat-triggered release of carbon bound up in soil, tundra, and the Arctic sea bed.
Tipping all these feedbacks together would be like striking a match. They would dramatically amplify the effects of human-caused global warming, perhaps doubling it. Wadhams scientific validation of the problem of sea ice reflectivity loss is a critical step in understanding how a warming Arctic can make the problem of human caused warming much worse. But what is needed, is a comprehensive study of all Arctic feedbacks and their potential additions to global warming over the coming decades. A similar study of the Antarctic is probably needed as well.
That said, given the wealth of evidence already collected, it is becoming increasingly clear that amplifying feedbacks is a growing problem in the Arctic. That pushing the Arctic too far is already amplifying the force of human global warming.
For more information on the risks of amplifying feedbacks in the Arctic, take a look at this article.