The state of the Arctic Sea Ice is of great concern to all of us, due to the change in the albedo's positive-feedback effect of raising temperatures in the Arctic region for more months in the summer.
The remnants of multi-year sea ice, which were to be found to the north of Baffin Island, have been moving in a southwesterly direction since April and have largely all melted away once they arrived to the south and west of Banks Island (this refers to the image on the right, representing February 2008). See the graphic below -- the green and purple areas represented the sea ice in question. Click on the graphic for more detail.
The pullback of ice and snow cover on the western coast of Greenland has arrived a good two weeks earlier than it did last year (which was already two weeks early). Click on the graphic, below, to see this in more detail.
As can be seen from the graphic above, in spite of what many people perceived to be a very cold winter, the pullback of snow cover in the Northern Hemisphere, particularly in northwestern Canada and northeastern Siberia, is progressing at a much faster pace than it did last year, a year that tied for second place as the warmest year on record for mean global temperature. This means that the methane-containing tundra will be melting even more than it did last year.
Link to the site of the graphic above (updates in the late afternoon): http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=01&fy=2007&sm=06&sd=01&sy=2008
The National Snow and Ice Data Center's graph of Arctic sea ice extent has been updated in the last few days. Note that the graph represents the area covered by at least 15% ice, and that it says nothing at all about the depth of the ice. Now that almost all of the multi-year ice has melted, the blue line on the graph represents primarily thin ice from last year. Thus, it is not possible to make a true comparison between the dotted line (year 2007) and the blue line (this year), as the blue line represents ice that is thinner than ice during the same period of time last year.
Link to NSIDC graph above (updated daily): http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
[UPDATE OF JUNE 11, 2008: a reader (Paolo Morelli) was kind enough to point me in the direction of a sea ice extent graph published on the site of the Japan Aerospace Exploration Agency, Earth Observation Research Center (JAXA/EORC) , all rights reserved by them, so I will just show the graph this time as an example, updates you will have to get from their site. The red line is year 2008. CLICK ON GRAPH TO ENLARGE]:
Link to their site: http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
The information published on the Cryosphere Today (a collaboration between the Universities of Illinois and Colorado) also shows the deterioration of the Arctic Sea Ice (see below). Click on the image to enlarge it:
Link to graphic above (usually updated by the early afternoon): http://www.iup.uni-bremen.de:8084/amsr/arctic_AMSRE_nic.png
As a special treat for those who enjoy 500-hPa height anomalies over the Arctic, here is an animation of the month of May over the Arctic (you can click on the image to enlarge it, but you have to click on the link below the image in order to see the animation):
Link to animation (updated daily, I think): http://www.cpc.noaa.gov/products/intraseasonal/z500_nh_anim.shtml
For those readers unfamiliar with the geography of the Arctic, you can find Baffin Island (off of northwestern Greenland) and Banks Island (the most north and western island of Canada) on this map, which also shows current temperatures if you click on the yellow dots (note: not all of the dots function):
Link to the above interactive map: http://www.athropolis.com/map2.htm
Here is a repeat of some information from an earlier post on this blog:
At Nuuk, Greenland, on May 23rd, the record set in 1998 (48 F) was broken by 5 F (53 F).
On the 24th, the old record set in 2001 (46 F) was broken by 16 F (62 F).
On the 25th, the old record set in 1998 (48 F) was broken by 3 F (51 F).
Note that the average temperature for this time of year is only 38 F.
See also: http://climatechangepsychology.blogspot.com/search/label/Arctic%20ice%20melt
And/or here: http://climatechangepsychology.blogspot.com/search/label/Greenland%20ice%20melt
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