[One more essay to contribute to the Paris’ CO2 negotiations!] One has to be careful with science. Science is certain knowledge. And certain knowledge is not just hard to gather, it is subtle, and even harder to organize in a coherent logic. It is pretty much certain that Antarctica will melt (in my opinion). However a NASA study, just out, claims that Antarctica is gathering a huge amount of ice:
“A new NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.
The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice.
According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.”
This, paradoxically, does not contradict any of my apocalyptic predictions about Antarctica. Quite the opposite: a greater snowfall is a mark of a warming climate. Warmer air carries more moisture. The gathering of snow and ice in the interior and at high altitude, over wide expanses has not effect to the melt extending below.
In truth, the situation is dire and will evolve quickly. One is reminded of the Space Shuttle Columbia, when hot gases penetrated in its left wing. After they got in, they melted vital equipment all over inside, including hydraulics, and the shuttle struggled for control, finally losing its wing.
Antarctica’s ice shelves — the thick, floating slabs of ice which encircle the continent — are melting. The shelves slow and stabilize the glaciers, hundreds of kilometers behind them. They are succumbing to a hidden force: deep, warming ocean currents are melting the ice from beneath ice shelves, and up giant valleys penetrating the continent.
The collapse of small ice shelves caused glaciers to accelerate two-fold to ten-fold and spill more ice into the ocean, raising sea level. A study published in April shows that more ice shelves are threatened: From 1994 to 2012, the rate of ice shelf shrinkage increased twelvefold. Parts of the ice sheet considered at risk hold enough ice to raise the global sea level by 22 feet (seven meters). Here’s the latest on Antarctica’s vulnerability in 2015:
More Snow, Less Ice:
Climatologists speculated in the 1990s that Antarctica might slow sea level rise. They fancied that rising temperatures would produce more water vapor, leading to more snowfall and more ice. This is indeed what the latest NASA study shows. Researchers reported in March, and November 20215, that over the past 20,000 years, warmer temperatures have indeed correlated with higher snowfall: For each Fahrenheit degree of warming, snowfall increased by about 2.7 percent. But that does not mean the threat of fast melting receded..
Larsen B’s Last Gasp:
Glaciologists reported in June that the last remnant of the Larsen B Ice Shelf is splintering, and glaciers flowing into it are accelerating. Its approaching demise continues a disturbing trend: the progressive collapse of five ice shelves since 1989.
Next, Larsen C:
The neighboring, and much larger Larsen C Ice Shelf, a significant part of the Antarctica Peninsula, could soon collapse (hey, it’s summer!). A major crack is advancing rapidly, reaching an unprecedented 60 miles long in early 2015. (A British base in the Ross Ice Shelf is threatened by another advancing crack, and is scheduled to be moved ASAP! A German base disappeared altogether.)
Southern Peninsula “Starting to Sweat “:
(“Sweating” was the term used in a scientific report…) While the glaciers in this region seemed stable, warming ocean currents have been melting the belly of the ice. Results published in May show this region crossed a threshold in 2009, with a dozen major glaciers simultaneously starting to thin, “sweating off” 60 billion tons of ice per year.
The Amundsen Sea coast is the vulnerable underbelly of West Antarctica. Its glaciers slide on beds that lie nearly a mile below sea level, exposing them to ocean currents. New data show ice shelves are collectively losing 100 billion tons of ice per year, and glaciers have accelerated by up to 70 percent.
Hidden Hazards in the East:
East Antarctica, situated on high ground that protects it from warming ocean currents, was considered stable, impervious, a Reich to last 10,000 years, strong and dominating. But not exactly, according to surveys with ice-penetrating radar. A March study shows that one large swath of the ice sheet sits on beds as deep as 8,000 feet below sea level and is connected, by very long, deep valleys to warming ocean currents. Totten Glacier, one of East Antarctica’s largest ocean outlets, is already thinning — an ominous sign, since this single glacier drains enough ice from the AURORA Basin to raise the sea level more than all of West Antarctica’s ice loss would. The mouth of the Totten glacier is well north of the southern polar circle. This means that the potential for warming from decreased albedo is considerable.
The same story is unfolding with the Wilkes Basin, as I have explained.
Thus, right now, sea level is rising slowly, and climate change deniers are chuckling, because Antarctica is gathering warm snow. But, once the warm currents penetrate in force, and they will, Antarctica will go the way of the Space Shuttle: sudden, irresistible disintegration.
A last riddle is that, should the latest story (above) from part of NASA, be correct (and not another piece of disinformation to serve the fossil fuel plutocracy, as happened more than once in the past), how come sea level is increasing as fast as is presently observed? The math just don’t add up: the greatest contribution to sea level rise comes in with the wrong sign! So either the latest NASA accumulation studies are wrong, or there is a massive contribution to sea level rise undetected so far (the worst is imaginable…) Just when we saw that the Green House Gas disaster was boring in its irresistible unfolding, a new mystery surfaces…