As the world's oceans absorb more and more heat trapped by our increasingly carbon laden atmosphere the warmer sea water is melting the massive Antarctic ice shelves from below, a new survey utilizing NASA's CESat satellite shows.
What's to blame for melting Antarctic ice?
The team's results represent the culmination of a massive international effort to observe the loss of Antarctic ice from the skies. Using NASA's ICESat satellite, the researchers closely monitored how the thickness of West and East Antarctica's ice changed over time. In some cases, Pritchard said, shelves thinned by as much as several meters each year. And the pattern of that melting, he added, suggested that at least 20 out of 54 observed platforms of ice across the continent were being melted largely by the oceans below, much like a warm drink consuming ice cubes.
While the exact factors driving the warming of Antarctic waters aren't known, scientists suggest that past toasty conditions in the tropics have created strong winds to the south in Antarctica, fueling ocean currents that bring hot water to the surface.
Glacier speed-up
Regardless, the trend spells trouble for the continent, the team said. That's because floating ice sheets act as a brake against the loss of Antarctica's land-bound rivers of ice, or glaciers. As these shelves melt away due to warming waters — mostly in West Antarctica — glaciers have begun to spill more and more ice into the seas.
This comes from a USA Toay from 1999:
Answers to sea level rise locked in ice
By Jack Williams,
Water from a melted West Antarctic sheet could push global sea levels as much as 20 feet higher than they would otherwise be.
Scientists say the West Antarctic sheet is more likely to collapse than the large East Antarctic sheet because its bottom is mostly below sea level. East Antarctica’s ice is mostly grounded above sea level.
When it comes to climate change driven Sea Level rise accelerated melting of the Antarctic ice shelves is what scientists fear most. A catastrophic event that would profoundly redraw the map of the world as sea levels could potentially rise 20 feet.
I have a family back story about Antarctic ice shelves. My brother spent an Antarctic summer drilling ice cores on the Ross Ice Shelf and then taking high precision measurements of the ice's temperature at different depths in the borehole. He slept in a tent and traveled by snowmobile to core drilling sites in 0 F weather for a season. He was working with a team of scientists to gather data on the Ross Ice Shelf as part of a Teachers in Science Program. Here was his location