Message from the mud: East Antarctic meltdown could cause massive sea rise

[IDemo]

The last time concentrations of the greenhouse gas carbon dioxide were as high as they are today, big chunks of the seemingly stable East Antarctic ice sheet melted and helped raise global sea levels more than 65 feet higher than they are now, a new study suggests.

Scientists have long known that seas were higher during the Pliocene, a geological epoch that ran from 5.3 million to 2.6 million years ago. At the time, atmospheric carbon dioxide levels were similar to today's 400 parts per million (ppm).

"Overall, it was a warmer climate than today, but similar to what we expect to reach by the end of this century," Carys Cook, a graduate student at the Grantham Institute for Climate Change at Imperial College London and the study's lead author, told NBC News in an email.

The West Antarctic and Greenland ice sheets were likely completely melted at the time, she added. The fate of the East Antarctic ice sheet has been less clear, though at least some of it must have melted to fully account for the highest global sea levels predicted by some reconstructions of the ancient Earth.

http://www.nbcnews.com/science/message-mud-east-antarctic-meltdown-could-cause-massive-sea-rise-6C10687020

[Gregorian]

1. The concept of multiplicity seems to go over everybody's heads.

It's just me. I'm going on vacation. One trip won't hurt anything.

No, it's "just me" times a billion.

It's not going to change. My prediction is with 15 million new humans put on the planet each and every week, we're simply going to turn this place into a steaming heap.

[Warpy]

2. Most people don't realize just how fragile this civilization of ours is

and how little it will take to disrupt it to the point we'll be back in the Stone Age in just a few generations.

Yes, the record is crystal clear, there have been dramatic rises in sea level in the past, up to 75 feet. There is no reason to believe they won't happen in the future, the increased water volume the planet's way of trying to neutralize all the excess CO2 we've pumped into the atmosphere. The rise might take 10-20 years, but that's a blink of an eye in geologic time and the disruptions to all our systems, especially trade and financial, will be catastrophic. Add to that the famines resulting from rapid climate change elsewhere and the epidemic disease that follows close on famine's heels and you will shove us right back into hunting and gathering, those few of us who survive.

[kestrel91316]

3. No shit, Sherlock.

[FirstLight]

4. seriously?!

"Overall, it was a warmer climate than today, but similar to what we expect to reach by the end of this century,"

WHEN will they understand the feedback loop means EXPONENTIAL changes over time? EVERY timeline they have modeled has been off by decades...this is going to occur so fast, millions will be caught with their proverbial pants down, because the governments of the world are still debating over whether it is even happening...as the water rises over their heads...

[OKIsItJustMe]

5. Ancient global warming caused parts of Antarctica's ice sheets to melt.

http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_22-7-2013-11-19-2

[font face=Serif][font size=5]Ancient global warming caused parts of Antarctica's ice sheets to melt.[/font]

by Colin Smith | 22 July 2013

[font size=4]This ancient thaw may have caused sea levels to rise by approximately 20 metres, scientists report today in the journal Nature Geoscience.[/font]

[font size=3]The researchers, from Imperial College London, and their academic partners studied mud samples to learn about ancient melting of the East Antarctic ice sheet. They discovered that melting took place repeatedly between five and three million years ago, during a geological period called Pliocene Epoch, which may have caused sea levels to rise approximately ten metres.

The team say that the East Antarctica ice sheet melt may have contributed to 20 metre sea level rises

Scientists have previously known that the ice sheets of West Antarctica and Greenland partially melted around the same time. The team say that this may have caused sea levels to rise by a total of 20 metres.

The academics say understanding this glacial melting during the Pliocene Epoch may give us insights into how sea levels could rise as a consequence of current global warming. This is because the Pliocene Epoch had carbon dioxide concentrations similar to now and global temperatures comparable to those predicted for the end of this century.

…[/font][/font]

http://dx.doi.org/10.1038/ngeo1889