Arctic Methane From Tundra Could Add .4 to 1.5+ Degrees Fahrenheit to Human-Caused Warming

A recent paper in Nature Geoscience has shown that human caused warming could pump enough methane out of the Arctic tundra to raise the Earth’s temperature by between .4 and 1.5 degrees Fahrenheit. The paper, entitled Significant contribution to climate warming from the permafrost carbon feedback, showed that between 6 and 44 percent of all permafrost carbon could be emitted by 2100.

Since there’s more carbon in the permafrost than what has been historically emitted via fossil fuels, this number is large and very significant. The result of such an emission, even on the lower end, would be a significant contribution from nature to an already difficult to deal with man-made warming.

Research indicated that carbon emissions would be equal to between 40 and 100 additional parts per million CO2. However, a substantial portion of this increase would, initially, be methane, which, as a greenhouse gas, is 25 to 70 times stronger than CO2. This would seem to indicate that the researchers’ initial estimates of warming potential from permafrost carbon emission is low. And the researchers, themselves, admit their first estimates are conservative.

Perhaps, the most ominous outlook in the study is that it found that the amount of greenhouse gases to be emitted from permafrost over the next century largely cancel out carbon absorption by the oceans. Furthermore, the study did not take into account carbon emissions coming from methane hydrates in the ocean or from carbon sources in Antarctica once significant areas of that continent begin to thaw.

What this means is that, even were CO2 emissions to cease this decade, CO2 levels will likely remain above 400 ppm for as much as three hundred years. And this extended duration of high CO2 has substantial repercussions when it comes to the future shape of the world’s ice sheets and future ocean levels.

What this also means is that we are essentially locked in to melting Greenland and West Antarctica and to an additional 2-3 degrees Celsius warming now. Continued emissions via fossil fuels make the problem of global warming even worse. Andrew Skuce, in a recent response to this paper published in Skeptical Science noted:

“Unfortunately, there are several good reasons to consider the outlook in this study as rosy — as the authors themselves make clear. However, as bad and inevitable as they are, feedbacks from the permafrost are just the (de-)frosting on the fossil fuel cake that we are busy baking. It is still up to us to influence how severe climate change is going to be.”

Skuce is somewhat euphemistic and unclear in his assessment. I will not mince words. We are on track to a hotter world if we stop fossil fuel emissions now. Things are even hotter if we cut back fuel emissions soon. Continued fossil fuel emissions, without reductions, however, puts us on a short path to 1000 ppm CO2 by the end of this century. And that path is a short, hot road to hell.

Links:

http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1573.html

http://thinkprogress.org/climate/2012/10/06/970721/carbon-feedback-from-thawing-permafrost-will-add-04f-15f-to-total-global-warming-by-2100/

A Cautious Call For Start of Seasonal Arctic Re-Freeze

Six days after the typical end to the Arctic melt season shows some pretty clear evidence of a beginning to seasonal re-freeze. JAXA shows sea ice extent more than 250,000 square kilometers above the record low set just a few days ago. Cryosphere Today is showing sea ice area about 150,000 square kilometers above the record low also set at that time.

Though it is possible for melt to resume, each day of refreeze makes that potential less likely.

It is worth noting that NSIDC seems to also be calling for the melt season’s end with its new record low value of 3.41 million square kilometers having posted on September 16th and called the final low on September 19th. This value of 3.41 million square kilometers is a departure of 760,000 square kilometers below the record low set in 2007 and an 18% loss since that record low year.

Total losses for NSIDC sea ice extent are now 66% below best estimates for sea ice extent averages in the 1950s, 57% from the 1979 figure, 51% below the 1979-2008 average, and 18% below the last record low. By all long, medium, and short term measures, these departures show a consistent and devastating trend of sea ice extent loss. Volume losses, according to PIOMAS are now 78% below 1979, but final measurements for September aren’t yet in. So we can, potentially, expect greater volume losses once PIOMAS issues its report for this month.

The Arctic has suffered a devastating blow from which it is unlikely to significantly recover. Sea ice measures for area are more than 2.44 million square kilometers below the average for 1979-2008 and more than 3.5 million square kilometers below the typical measurement for this time of year in 1979. Measurements are also still about 500,000 square kilometers below the values during the extreme record melt season of 2007. That said, thin, one-year ice will likely show significant growth during the fall and winter months even as average values are likely to remain below the baseline extent for 1979-2008. In fact,with values so low for this year, it is possible that a number of months during fall and winter 2012-2013 will see record low averages and that summer 2013 will emerge more fragile than even 2012.

These measurements and assessments, if nothing else, show that this refreeze is just a small respite in a much larger melt trend that has been ongoing since at least the 1950s and is trending for an ice-free or near ice-free Arctic within the next 3-20 years.

Links:

http://arctic.atmos.uiuc.edu/cryosphere/

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

http://nsidc.org/arcticseaicenews/

‘Year of Epic Melt’ Continues to Hunt New Records in Arctic, Highlights Ongoing Reality of Global Warming

For the Arctic, this has been the year of epic melt. Greenland broke its record for melt in early August, more than a month before melt normally ends, and Arctic Sea ice has been tracking at daily record low levels since the end of July. Now, every few days seems to bring with it a new major record. Just yesterday, sea ice area broke its all-time record low and today sea ice area continued to show losses.

The Arctic sea ice monitor Cryosphere Today showed sea ice area at a new record low of 2,844,000 square kilometers for the date. This is 61,000 square kilometers below the previous record low and with more than three weeks of melt remaining, final values will almost certainly be even lower.

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To put things in perspective, the 2.84 million square kilometer ice area measurement for today compares to a sea ice area low for the end of summer in 1986 of about 5.5 million square kilometers. The size of the current ice sheet floating over polar waters is nearly half that of what it was just 26 years ago.

The measure for sea ice extent is also rapidly falling. Values from both the NSIDC and the Japanese Space Agency show sea ice extent measurements at around 4.5 million square kilometers. This is less than 300,000 square kilometers above the record set in 2007. At the current rate of melt, a new record low for sea ice extent will likely be seen within the week.

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Sea ice volume also continues to track toward new record lows.

And according to Neven over at the Arctic Ice Blog, a new low for Northern Hemisphere snow cover has also been reached.

If the volume and extent values fall, then all previous records for Arctic melt including Greenland, Sea Ice Area, Sea Ice Extent, Northern Snow Cover, and Sea Ice Volume will have been broken this year.

This year of epic melt has occurred at the same time as the hottest July for Northern Hemisphere land masses ever recorded. Russia has experienced its hottest summer in at least 170 years while the US has experienced its hottest 12 months ever on record. The heat has also ignited massive fires and resulted in the worst drought since 1956 in the US.

In the Arctic, sea ice melt usually ends sometime around mid September. So we have weeks to go before we can declare an end to a season that has clearly set in bold for all the world to see these two words:

GLOBAL WARMING.

Links:

http://arctic.atmos.uiuc.edu/cryosphere/

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

http://nsidc.org/arcticseaicenews/

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