The National Snow and Ice Data Center (NSIDC) office at Boulder, Colorado, which I visited last week, has analyzed Arctic sea ice age. Comparisons show that the area of older Arctic ice shrank from March 2007 to March 2008.
I had a two hour discussion on changes in the Arctic and global warming with Mark Serreze, Senior Research Scientist at NSIDC, on Friday afternoon, May 23rd.
Arctic sea ice areal extent shrinkage was also discussed.
Links follow.
http://nsidc.org/arcticseaicenews/
http://nsidc.org/arcticseaicenews/2008/040708.html