Friday, March 27, 2015

Antarctica's Melting Edges Bad News for Sea Level Rise

'Within a lifetime of people who read this story, many of these shelves will be gone...This is real rapid environmental change," says reviewer of new study.

Eighteen years of change in thickness and volume of Antarctic ice shelves. Large, deep red circles correspond to the biggest melting of ice shelves, while smaller, blue ones mark those areas that gained a bit of thickness in the last two decades. (Credit: Paolo, et al./Science/Scripps Institution of Oceanography, UC San Diego) Click to Enlarge.
The edges of Antarctica's ice sheets have been thinning at a rapid rate over the past decade—up to 70 percent faster than average in some spots—due to warming oceans and air.

Known technically as ice shelves, these edges float just offshore in bays or fjords and act as barriers that keep larger, land-based ice sheets from slipping into the ocean.  Once they are gone, there will be nothing to hold back the continent-sized ice masses from sliding into the warmer oceans and melting, raising sea levels precipitously.

According to a new study published in the journal Science this week, this could happen by the end of the century.
Researchers have historically focused their attention on land-based ice sheets in Greenland and Antarctica because they are massive contributors to sea level rise, said Fernando Paolo, a graduate student at the Scripps Institution of Oceanography at the University of California-San Diego and the lead author of the new paper.

When ice shelves melt, however, they don't raise sea levels directly because they are already in the ocean.  But Paolo calls them an "overlooked, yet fundamental piece in the whole sea level rise process."  Monitoring them could yield clues as to when this climate impact will go from bad to worse.

The paper comes two weeks after it was revealed that a glacier the size of California in East Antarctica has experienced rapid melting in recent years.  If this particular glacier, the Totten Glacier, reaches the ocean, it could cause sea level to rise more than 11 feet.

Read more at Antarctica's Melting Edges Bad News for Sea Level Rise

No comments:

Post a Comment