10 September 2012

Arctic Ice Is Disappearing and Our Weather Will Never Be The Same

Posted by Dan Satterfield

From Kinnard et. al in Nature (http://www.nature.com/nature/journal/v479/n7374/full/nature10581.html) Hat tip to Way Things Break for leading me to this.

With every passing year it becomes more apparent that the Arctic Ocean sea ice seems to be in a death spiral. The ice area this September is 45% below the levels during September in the 1980’s, and almost certainly it is at levels that haven’t been seen for a thousand years (and likely much more). The melt back this year smashed the record set back in 2007, and we have now reached a level that was actually considered nearly impossible ten years ago.

Think about that for a second, it’s truly an astounding fact, and there is no doubt that this is changing the  weather we experience. The Arctic is the Northern Hemisphere’s air conditioner, and it is undergoing a rapid change at an unprecedented rate. Let me emphasize that point because there truly is NO DOUBT that this loss of sea ice will have a significant effect on our weather and climate. Not in fifty, or one-hundred years, but now and this coming winter too.

What The Science Says

From NOAA NSIDC

All that open water will refreeze this winter, and when it does an amazing amount of heat will be released into the atmosphere of the High Arctic. The atmosphere of course holds very little of the planet’s heat, it’s mainly stored in the oceans. You might be surprised to learn that 84% of the greenhouse warming in the last 50 years has gone into the oceans, not the air. This is why I can confidently say that there is no doubt that the melting arctic sea ice is changing our weather. The question of course is how it will do so!

There are a lot of researchers asking just that question in the science community right now. One such person is Dr. Jennifer Francis at Rutgers University, and she makes a compelling argument that the loss of ice is already causing atmospheric road blocks to develop more frequently. These “cut off lows and highs” can cause extreme and unusual weather, both in the form of winter snow storms and summer droughts. I’ve mentioned Dr. Francis before here and you can see a talk she made earlier this year here. There is a really good list of some of the latest research at the bottom of an excellent post about the effects of the ice loss at The Way Things Break. Very well worth a read, and Dr. Jennifer Francis’s paper in GRL is listed as well.

From NSIDC: Throughout the month of August, Arctic sea ice extent tracked below levels observed in 2007, leading to a new record low for the month of 4.72 million square kilometers, as assessed over the period of satellite observations,1979 to present. Extent was unusually low for all sectors of the Arctic, except the East Greenland Sea where the ice edge remained near its normal position. On August 26, the 5-day running average for ice extent dropped below the previous record low daily extent, observed on September 18, 2007, of 4.17 million square kilometers. By the end of the month, daily extent had dropped below 4.00 million square kilometers.

The Weather Charts Are Already Wonky

Chris Reynolds at the DOSBAT blog has a fascinating post about the string of wet summers in the UK, and the unusually persistent Greenland high over the past 5 years. This seems to align with the research of Dr. Francis and it is certainly something worthy of more investigation. The question here is what are the physical processes involved and can they be used to make a direct connection between the Greenland high and a much warmer Arctic Ocean. That ocean is absorbing much more heat than before because the ice cover that once reflected much of the sun’s energy has been replaced by dark water that is now absorbing most of it.

From the Polar Research Center at the Univ. of Washington. This graph shows not area but the volume of the Arctic Sea ice.

The volume of the Arctic Sea ice is harder to measure, but the new Cryosat2 satellite seems to be indicating that the Polar Science Center’s PIOMAS model is correct and the model indicated that we have now set a record low in the volume of the ice as well.

There are other ocean/atmosphere oscillations that affect the amount of Arctic sea ice, but new research shows that rising greenhouse gases are very likely now the dominant player. Could we see a temporary recovery? Yes indeed, but the long-term trend is likely to be a rapid decline. It’s possible that during the warmest natural period of this interglacial (6-9 thousand years ago  in high latitudes) that the Arctic ice might have been as low as it is now, but that really matters little. The laws of physics are real, and the math does not lie, so all that extra heat going into the oceans has to melt something.

Final Notes: I’ve tried to write a quick basic summary here for those with no science background, but if you find this fascinating like I do, then you will want to bookmark Neven’s Arctic Sea Ice Blog. A ton of great info about the science of the ice is there. Jason Box who is a researcher and expert on Greenland’s ice sheet also writes Meltfactor.org. A very good summary paper is available (open access!) here.

Besides the fact that we are conducting a planet wide experiment with serious consequences, the science itself is IMHO riveting. We are witnessing an amazing event that most people are not even aware of, but if they turn on cable news the only thing they are likely to see is an advert touting the the laughable myth that coal is clean energy.