Hi Eric,
> But the reduction in multi-year ice was the main focus of the Nghie, et
> al. paper. The trends in winter ice extent appear to be declining from
> other satellite measurements as well. Did you see the reference to
> Comiso's in-press report in the GRL?
>
> http://www.nasa.gov/pdf/157359main_Comiso_GRL06_AbrChArcWntrRevf1.pdf
You are quite right. The retreat of the multi-year ice is well known.
What I intended to convey can best be explained in the context of the
paper above, where in ht ebeginning of Introduction Joey Comiso writes:
"Before 2005, the maximum extent of the Arctic winter sea ice cover
as observed from satellite data has been changing modestly with the
trend being negative but only about -1.5% per decade. In contrast,
the Arctic perennial ice area has been declining at a rapid rate of
about -10% per decade [Comiso, 2006]. The trend for the entire
hemisphere and for all season has been modest as well being
between -2 to -3 % per decade [Bjorgo et al., 1997; Parkinson et al.,
1999]."
In other words, although the multi-year ice has been retreating at
-10% per decade, the scientists who were monitoring the trend for
the whole hemisphere only saw a "modest" trend. The reason is that
the winter ice is twice the extent of the summer ice. So when you
calculate the annual trend, the winter trend (which is only 1.5% per
decade) has twice the weighting of the summer trend.
> There's also some evidence of increased inflow of water from the North
> Atlantic. The Atlantic water has intruded further into the Arctic
> Ocean than previously seen. Sorry, I don't have the reference handy.
> It's all just another nail in the coffin for those that keep saying
> that there's no global warming.
You are correct again. The lack of growth of winter ice was mainly
confined to the eastern Arctic bordering the North Atlantic.
However, if an El Nino does inject warm Pacific into the Arctic,
then we could see a the ice being attacked on two fronts. This rather
Maslowski's conclusion "that the Arctic will soon be ice-free in
summertime."
But more, the winter ice is not regrowing in the eastern Arctic, so
without a large summer multi-year ice pack, we may find that there
is no winter ice pack either!
Cheers, Alastair.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
Global Change ("globalchange") newsgroup. Global Change is a public, moderated
venue for discussion of science, technology, economics and policy dimensions of
global environmental change.
Posts will be admitted to the list if and only if any moderator finds the
submission to be constructive and/or interesting, on topic, and not
gratuitously rude.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/globalchange
-~----------~----~----~----~------~----~------~--~---
