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penguins don't catch on so quickly

It's tough living on the edge when the edge starts moving. 

http://news.bbc.co.uk/2/hi/science/nature/7851276.stm

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( 9 comments — Leave a comment )
kelloggs2066
Jan. 27th, 2009 06:47 pm (UTC)
Thing I can't figure out from reading the article:
They talk about "Climate Change", rather than the usual "Global Warming". This is good, since the Antarctic has been getting colder, and it's ice pack has been expanding.

When they talk about the year 2100, do they assume that the ice pack will continue to expand, or do they assume that it's going to contract?

They don't actually say What the climate of Antarctica is going to do, except change.

While they say "Particularly warm seasons cause Antarctic ice to break up early" in the photo caption, that isn't what's happening down there.

So, frankly, I don't know what to make of the article, and I don't think you can entirely blame it on the fact that I'm a bit woozy...
marmoe
Jan. 27th, 2009 09:44 pm (UTC)
The abstract on the research article is at
http://www.pnas.org/content/early/2009/01/26/0806638106.abstract
Antarctic sea ice extent (SIE) is projected to shrink as concentrations of atmospheric greenhouse gases (GHGs) increase, and emperor penguins (Aptenodytes forsteri) are extremely sensitive to these changes because they use sea ice as a breeding, foraging and molting habitat.

I've seen a feature on the observed impact of recent warmer winters on other penguins (Adeli, IIRC) on TV some time ago. As far as I recall the chain of events is as follows:
warmer winters --> less ice --> less algae growing beneath the ice --> less food for krill --> less food for penguins (they caught penguins, dissected them and checked the content of the stomach to get an estimate of krill population), further to go for foraging (penguins with GPS) --> less offspring. Some of the colonies were gone already.
Fishing of krill by mankind and whales will of course also impact its population.
IPCC on Antarctic ice sheet:
In Antarctica, temperatures are so low that comparatively little surface melting occurs on the continental ice sheet; ice loss is mainly by iceberg calving, the rates of which are determined by dynamic processes involving long response times (thousands of years). Even if Antarctica were to warm in the future, its mass balance is expected to become more positive: The rise in temperature would be insufficient to initiate melt but would increase snowfall (IPCC 1996, WG II, Section 7.4). Little change in Antarctic ice sheets is expected over the next 50 years, although longer-term behavior-including that of West Antarctic ice-remains uncertain, and some instability is possible. Some areas of Antarctica may show a pronounced change and dynamic response. The Antarctic Peninsula, for instance, receives 28% of the continent's snowfall and experiences warmer temperatures and summer melting at sea level. A rise in temperature would be expected to cause continued wasting of marginal ice shelves in the Antarctic Peninsula, but this melting has no direct effects on sea level, nor is it indicative of changes in the Antarctic ice sheets.
Sea ice extent data can be found here
http://arctic.atmos.uiuc.edu/cryosphere/
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.jpg
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.south.jpg
Not sure, whether the overall increase in the Antarctic sea ice extent is statistically distinguishable from "no change". We definitely do not see a dramatic decrease like in the Arctic, except for the area of the Antarctic Peninsula, which is stretching towards South America.
marmoe
Jan. 28th, 2009 12:33 pm (UTC)
One more about Climate Change vs. Global Warming. Both terms have been around since 1975 at a minimum (wikipedia claims that "GW" was coined in this paper). In recent years, there has been a concerted, political effort to use "Climate Change" rather than "Global Warming", because it sounds less threatening. One Memo to the Republicans, including President Bush, has become quite famous: "The Environment: A cleaner, safer, healthier America" by Frank Luntz (see, e.g. page 12). More background can be found in this article in The Guardian.
sleepyjohn00
Jan. 29th, 2009 03:39 am (UTC)
From the reports I've seen, the ice pack may be expanding because, given several years of higher-than-normal temperatures, the glaciers are flowing at record speed and calving into the sea.

Unfortunately, "global warming" is the phrase that people have in their heads, instead of "climate change", so whenever there's an ice storm someplace, people argue that, see, the earth isn't warming up!
marmoe
Jan. 27th, 2009 10:01 pm (UTC)
You had that "The emperor demands respect" image up some time ago. I stumbled across the corresponding news item: Penguin Granted Norwegian Knighthood (with photos).

Best of luck to the Emperors.
sleepyjohn00
Jan. 29th, 2009 03:35 am (UTC)
Yay! Huzzah for Norway! Have to tell Won-Tolla about this...
dianagaidheal
Jan. 28th, 2009 03:20 am (UTC)
Isn't the same happening to polar bears, due to the melting of the ice?
deckardcanine
Jan. 28th, 2009 05:41 pm (UTC)
From the article: "They are to Antarctica what the polar bear is to the Arctic." -- Joel Cohen, Rockefeller University
dianagaidheal
Jan. 29th, 2009 01:59 am (UTC)
thanks
( 9 comments — Leave a comment )

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