Reversing Greenland ice sheet's melt-off could be impossible
• Article by: AMY HUBBARD , Los Angeles Times   • Updated: March
17, 2012 - 5:03 PM  If that ice disappears, sea level could rise
23 feet.   July 19, 2007 file photo, an iceberg off Ammassalik
Island in Eastern Greenland.  Photo: John Mcconnico, Associated
Press - Ap  CameraStar Tribune photo galleries  Cameraview
larger  LOS ANGELES - The Greenland ice sheet has a lower
melting point than previously thought, with scientists saying
not only that it could melt completely at a lower temperature
than once believed, but also that the melting process could soon
become irreversible.  "Once the process of melting the ice
begins, it is very hard for it to change course even if we can
lower temperatures in the future," Alex Robertson, lead author
of a new study, said by e-mail.  Next century tells the tale
"So even though melting the whole ice sheet could take a really
long time, we will essentially decide the fate of Greenland
within the next century."