Posted on 03/26/2006 9:40:44 PM PST by quantim
The Earth’s warming temperatures are on track to melt the Greenland and Antarctic ice sheets sooner than previously thought and ultimately lead to a global sea level rise of at least 20 feet, according to new research.
If the current warming trends continue, by 2100 the Earth will likely be at least 4 degrees Fahrenheit warmer than present, with the Arctic at least as warm as it was nearly 130,000 years ago. At that time, significant portions of the Greenland and Antarctic Ice Sheets melted, resulting in a sea level about 20 feet (six meters) higher than present day.
These studies are the first to link Arctic and Antarctic melting during the Last Interglaciation, 129,000 to 116,000 years ago. "This is a real eye-opener set of results," said study co-author Jonathan T. Overpeck of The University of Arizona in Tucson. "The last time the Arctic was significantly warmer than present day, the Greenland Ice Sheet melted back the equivalent of two to three meters (about six to ten feet) of sea level."
Contrary to what was previously believed, the research suggests the Antarctic ice sheet also melted substantially, contributing another six to 10 feet (two to three meters) of sea level rise. The new findings will be published in the March 24 issue of Science.
Co-author Bette Otto-Bliesner of the National Center for Atmospheric Research in Boulder, Colo., said, "Although the focus of our work is polar, the implications are global. These ice sheets melted before and sea levels rose. The warmth needed isn’t that much above present conditions."
The ice sheets are melting already. The new research suggests the melting could accelerate, thereby raising sea level as fast, or faster, than three feet (about one meter) of sea level rise per century.
Although ice sheet disintegration and the subsequent sea level rise lags behind rising temperatures, the process will become irreversible sometime in the second half of the 21st century, Overpeck said, "unless something is done to dramatically reduce human emissions of greenhouse gas pollution.
"We need to start serious measures to reduce greenhouse gases within the next decade. If we don’t do something soon, we’re committed to four-to-six meters (13 to 20 feet) of sea level rise in the future."
As sea levels rise, coastal regions are more susceptible to the impacts of storm surge. The predicted rise would eventually inundate heavily populated coastal areas worldwide.
Overpeck, a professor of geosciences and director of Institute for the Study of Planet Earth at The University of Arizona, Otto-Bliesner and their colleagues report their new findings in a pair of papers. A complete list of authors is at the end of this release. The National Science Foundation funded the research.
The researchers used a computer model that scientists use to predict future climate, the NCAR-based Community Climate System Model (CCSM), and combined it with ice sheet simulations to estimate what the Earth’s climate was like 129,000 years ago.
The team also cross-checked the computer’s estimate of ancient climate against data from natural recorders of ancient climate such as sediments, fossils and ice cores.
The CCSM did a good job of estimating past climate changes. That gives the researchers additional confidence in the model’s predictions of future climate change, Otto-Bliesner said.
The work shows that meltwater from Greenland and other Arctic sources raised sea level by as much as 10 feet (about three meters) during the Last Interglaciation. However, coral records indicate that the sea level actually rose 13 to 20 feet (four to six meters) and sediments under the West Antarctic Ice Sheet indicate parts of the ice sheet disappeared.
Antarctic melting must have produced the additional sea-level rise, Overpeck concludes. He said the rise in sea level from melting in the Arctic could have destabilized parts of the Antarctic ice sheet.
In the last few years sea level has begun rising more rapidly, Overpeck said. He’s concerned, because unlike the Greenland Ice Sheet, the base of the West Antarctic Ice Sheet is below sea level. If it starts to melt, it could go fast, he said. Moreover, during the Last Interglaciation, most of the warming was in the Arctic and only in summer. Now the Earth is warming at both poles year round.
"To get rid of Greenland’s ice, you have to melt it. In the Antarctic, all you have to do is break up the ice sheet and float it away and that would raise sea level," he said. "It’s just like throwing a bunch of ice cubes into a full glass of water and watching the water spill over the top."
Overpeck said the team’s next step will be developing a more precise estimate of the threshold of ice sheet and sea level change beyond which major sea level rise is inevitable.
To be fair computer modeling is GIGO.
I've got about 12' at high tide and I can still sleep at night.
20 feet huh? Will we finally be done with New Orleans then?
Hell; I'd buy me a Suburban if that'd help.
The article said -- ""The last time the Arctic was significantly warmer than present day, the Greenland Ice Sheet melted back the equivalent of two to three meters (about six to ten feet) of sea level."
Well..., what caused the warming last time? If there were no "greenhouse gasses" in play then -- it must have been something different.
Therefore, perhaps the same mechanism is in play now -- and we're all barking up the wrong tree by saying it's "greenhouse gasses" and we have to do something about it.
If this is happening -- then I know what to do -- move back from the edge of the ocean. You've got a hundred years to do it.
Regards,
Star Traveler
This is the sixth article posted about the same study from six different moonbat sources...
Don't know if the intention is to pretend that there are multiple valid sources for the doom and gloom thing, or if the nutcases have a union now, got organized and are now posting the same thing over and over again.
One reason might be that nobody (with at least half a brain) is buying it and research grant money is at stake.
Big bucks from people like George Soros and the Heinz chain of organizations will stop if these people fail to come up with some man-made global warming.
Each "new" report is flakier than the one before.
ping
They can't even accurately predict the weather for the next day, but they can tell you whats going to happen by 2100, and what the temperature was 130,000 years ago?
They should have started this article with: "Once upon a time, a long, long, long, long, long, long, long, long time ago and in the far off future 94 years from today",............
Does this mean I won't have to drive quite as far to get to the ocean? Cool...
Start building your arc!
Junk science.
You can reduce "greenhouse gases" tomorrow, and it wouldn't change a thing.
One Krakatoa size volcano can spew out enough gases and ash to cool the entire planet, and volcanic eruptions can happen at any time.
There are many reasons why a planet heats up or cools off, and for humans to think that they alone are the cause or cure is pure narcissism.
160,000 Years ago? Maybe there is something to this prior civilization called Atlantis and all their flying machines warming up the earth. God knows it could not be a cyclical pattern to the earth, or it could be dinosaur flatulent that caused all the hot air.
I wonder if they setting that 20 foot mark at high tide or low tide. FOTHFLOL
Oh drat either way, that means that my brother and his wife will be moving in with me.
The oceans will rise between 0.5 inches and 20 feet. You can take that to the bank.
I've packed a lot of Styrofoam into my wheelchair, not worried. </s>
"Although ice sheet disintegration and the subsequent sea level rise lags behind rising temperatures, the process will become irreversible sometime in the second half of the 21st century, Overpeck said, "unless something is done to dramatically reduce human emissions of greenhouse gas pollution."
And they know this how?
"These studies are the first to link Arctic and Antarctic melting during the Last Interglaciation, 129,000 to 116,000 years ago."
And man caused that how?
These people are nuts.
Geocentric Universe anyone?
What do you expect living on a molten lump of iron hurtling around a hydrogen bomb at incredible speed?
Sunni or later shiite happens
Know thy enemy. And perpetual repackaging of the MSM. Your point is illustrated.
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