Re: Massive ice shelf collapsing off Antarctica

On Mar 26, 5:31 pm, Gutless Umbrella Carrying Sissy
<tausti...@[EMAIL PROTECTED]
> wrote:


This particular ice shelf loss does not strike me as that big a deal
in and of itself.  Nothing like the Larsen B shelf lost a few
years ago.  That was much larger, and had been  there for
11,000 years.

If it matters particularly it is as part of a pattern, or because it
was
buttressing the larger ice shelf, which may now be more vulnerable.

Of course it really matters because we got some good data and
cool pictures.

>
> Isn't the overall average amount of ice on Antartica actually
> increasing the last couple of years?


Most of Antarctica is cooling, only the northern areas around
the peninsula (where this shelf is) are warming.  That Antarctica
as a whole would not warm noticeably for decades was predicted
long ago:

http://www.realclimate.org/index.php/archives/2008/02/antarctica-is-cold/#more-529

Ozone is also a pretty good greenhouse  gas, so the reduction in
Ozone over Antarctica has an actual cooling effect:

Shindell, D. T., and G. A. Schmidt (2004), Southern Hemisphere climate
response to ozone changes and greenhouse gas increases, Geophys. Res.
Lett., 31, L18209, doi:10.1029/2004GL020724.

Combine the two and you get a surface cooling over much of
the continent.  Luckily for us.

Also, keep in mind that cooling does not necessarily imply more ice,
nor warming less.  Depending on the initial state (how cold it was
at the start) and precipitation changes, a cooler climate may
result in a smaller ice sheet, a (somewhat) warmer climate in
a larger one.


William Hyde