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Antarctic Ice Bridge Finally Breaks Off
GreennMann writes "An ice bridge linking a shelf of ice the size of Jamaica to two islands in Antarctica has snapped. Scientists say the collapse could mean the Wilkins Ice Shelf is on the brink of breaking away, and provides further evidence of rapid change in the region. Sited on the western side of the Antarctic Peninsula, the Wilkins shelf has been retreating since the 1990s. Researchers regarded the ice bridge as an important barrier, holding the remnant shelf structure in place. Its removal will allow ice to move more freely between Charcot and Latady islands, into the open ocean."
http://www.gladwell.com/2004/2004_01_12_a_suv.html
I am a climate scientist. I've never been in politics and I've never sold anything (professional student here). I also think you're completely wrong. My experiences at the 2008 Fall Meeting of the American Geophysical Union are that most (9/10) of the scientists I met agree with the IPCC report on abrupt climate change.
But you've made an even more fundamental mistake. Science isn't democratic-- it's about evidence. Open up the IPCC reports yourself and focus on what's really important, instead of trying to count how many people are on each side.
For example, Vostok ice core data confirms that for nearly half a million years, the climate has changed cyclically. But in all that time, the maximum CO2 concentration never went above 300 ppm. (It's hit higher levels millions of years ago, but that was a slow and gradual change. Plus the Earth was essentially a different planet back then, with a different solar luminosity and biosphere so comparisons across that much time are tricky.)
You're right to say that natural variations are evident in the data, but the most prominent cycles over geological time are governed by (among other effects) Milankovitch cycles which are caused by periodic variations in the earth's orbit.
But, CO2 concentrations are at 380 ppm today. That's a level it hasn't hit in the last half million years. If we're seeing natural variability alone, it's quite a coincidence that it occurs right when we started excavating fossil fuels to fuel a billion cars.
Plus, the Vostok data is a little difficult to analyze in this manner, but it seems like at Vostok the CO2 always increased 600 years AFTER the temperature started to increase. At least, that's the way it used to work. Right now, the CO2 concentration is at an unprecedented level but the temperature is barely above normal. Again, that suggests that we're not facing natural climate change, we're dealing with anthropogenic abrupt climate change.
Most estimates don't account for melting of continental Ice (Antarctic). That is because most expect the antarctic climate to be stable. The observed melting of Ice is worse than the estimates suggested by climate models.
This causes concern that the antarctic climate could be much more dynamic than we think.
A change in the climate of Antarctica could lead to large amounts of continental ice melting, which would lead to sea level rises much more than a couple of feet.
You laugh, but...
http://www.physorg.com/news5619.html
---linuxrocks123
vi ~/.emacs # I'm probably going to Hell for this.
The Antarctic as a whole is not cooling, but warming with the rest of the world, some data from some places showed it was cooling and of course this was expounded by denialists as proof that warming wasn't global.
see : http://www.realclimate.org/index.php/archives/2009/01/state-of-antarctica-red-or-blue
The Antarctic's ice is melting much less than the arctic because the antarctic gets a lot of it's coldness from it's altitude (mountains etc), whereas the arctic is just floating ice, and is also adjacent to more land and less water - water stabilises temperature - so this makes the arctic more sensitive to temperature changes. But the edge bits are melting.
I think the ice shelves breaking is more likely to be caused by sea level rise though. Where the sea level cracks the ice off from the land. Which shows the non linear nature of ice melting. We don't just get ice melting linearly with temperature increases, we can get whole chunks breaking off and floating away