Posts Tagged ‘Snow’

Saharan Snow, Enjoy, It Will Not Last

December 21, 2016

Global warming is accelerating, as anticipated: the Arctic sea ice is the smallest ever for the season. Also the Polar Vortex wanders. As I have argued in the past, global warming also means, through equipartition of energy, great depressions, great high pressure, and great dynamics. Greats dynamics means great motions of whatever is big and can be moved. From depression, to wiggles in the jet streams, to the polar vortices themselves: whatever can move, will be moved.

This has brought some counterintuitive effects: for decades, Antarctic sea ice spread out away from the icy continent, pushed by stronger winds. Also the accelerating melting of the giant Antarctic ice shelves (some 1,000 kilometers wide), has brought to the surface light sweet water, which readily freezes above the colder, denser saltier ocean water below. Thus climate deniers chuckled that Antarctica was getting colder, whereas, in truth, was they were observing was the exact opposite.

Climate Denying Sites Published Similar Pictures, Where The Forest In the Background Cannot Be Seen, Of Course...

Climate Denying Sites Published Similar Pictures, Where The Forest In the Background Cannot Be Seen, To Make It Look More Miraculous, Of Course…

So, year after year, the Antarctic sea ice spread out, and that was a shining demonstration of the global warming. Of course, this sort of evolution evolves steadily away from equilibrium, until things break, and a completely new attractive minimum comes within reach. This apparently just happened with Antarctica: after a year where the sea ice spread more than two standard deviations above the average, now the sea ice is shrinking two standard deviations BELOW the average.

The Polar Vortex has wandered: for many weeks it was over Siberia. Instead of being around the North Pole. Thus the temperature at the Pole was 20 Celsius (roughly 40 F) ABOVE normal. Then the vortex went to North America last week, and temperatures plunged there. Now higher temperatures are again announced for the Pole.

Ah, and what of this Saharan snow? Actually it was in an Algerian locality perched at 1078 meters above sea level in the Atlas mountains. It receives rain, and is surrounded by (thin) forest. Although this particular locale had no snow for 37 years, it snows every year in the Atlas: Algeria has ski resorts. The Atlas culminate at 4167 meters in Morocco and stretches 2,500 kilometers (1,600 miles). Many peaks are above 4,000 meters, and the barrier is formidable. The Atlas actually creates the Sahara, as it blocks moisture from the Atlantic and Mediterranean to reach the interior of the continent (the Sierra Nevada does the same in North America, blocking much Pacific moisture).

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“What We Are Seeing Now In Greenland Is Out Of Bounds With Anything Seen In the Last Few Millions Year”

Two papers just published in Nature support my old opinion that the Greenland icecap is more fragile than it was previously assumed.  These papers arose from collaborations from many prestigious institutions, in several countries, with support from the US National Science Foundation. It uses new radioactive techniques (new in that context).

Basically, when exposed to the radiation of the natural environment, isotopic compositions get modified: elements become radioactive in specific ways; however, when tucked under kilometers of ice, said radiation does not reach the ground, and elements have a different isotopic composition; thus, scientists are now able to figure out what the ice cover was… even 7.5 million years ago.

A study pondered the Eastern Greenland ice cap. There are high mountains there (up to 3,700 meters). Computer models show that it should not have melted in the last 7.5 million years (some hopefully claim it never will, but that’s just fossil fuel industry driven computations…). This is indeed what was found in the isotopic studies. The leader of the study, Bierman, opined that:

“…the ice sheet in East Greenland responds to and tracks global climate change… The melting we are seeing today may be out of the bounds of how the Greenland ice sheet has behaved for many millions of years.”

That team collected only samples off the mountainous east side of Greenland. Its results don’t provide a definitive picture of the whole Greenland ice sheet. But its findings  provide strong evidence that “an ice sheet has been in East Greenland pretty much continuously for seven million years,” says Jeremy Shakun, a geologist at Boston College who co-led the new study. “It’s been bouncing around and dynamic — but it’s been there nearly all the time.”

However, people on the ground, see the ice sheet retreating by miles, every year, in some places, leaving an eerie landscape behind.

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Contrast does not mean contradiction: 

The other study in Nature was led by Joerg Schaefer of Lamont-Doherty Earth Observatory and Columbia University, looked at a small sample of bedrock from one location beneath the middle of the existing ice sheet. It came to what appears to be a contradictory conclusion: Greenland was nearly ice-free for at least 280,000 years during the middle Pleistocene — around 1.1 million years ago. This contradicts existing computer models: the Common Wisdom was that, after earth entered a period of glaciations 2.7 million years ago, camels disappeared from the High Arctic, and that was that.

“These results appear to be contradictory — but they may not be,” Bierman says. Both studies have “some blurriness… Their study is a bit like one needle in a haystack, and ours is like having the whole haystack, but not being sure how big it is.”

Both teams looked at isotopes within grains of quartz, produced when bedrock is bombarded by cosmic rays from space. The isotopes are created when rock is at or near Earth’s surface — but not when rock is buried under an overlying ice sheet. By looking at the ratio of two of these cosmic-ray-made elements — aluminum-26 and beryllium-10 caught in crystals of quartz, and measured in an accelerator mass spectrometer — the scientists calculated how long the rocks in their samples had been exposed to the sky, or covered by massive ice. The technique is not new, but was never applied before to cores from marine sediments. Now they are busy extending the methods to other places, including Antarctica.

All of this will allow to evaluate better the probability of melting of the ice sheets in the present conditions.

I think the real danger comes from Antarctica, and it’s coming soon. “But there’s enough sea-level rise tied-up in Greenland alone to put a lot of cities and long stretches of coastline underwater,” says Paul Bierman, “including Donald Trump’s property in Florida.”

Well, Trump knows this (whatever he says to assuage his most clueless, suffering supporters). And thus Trump may do more than Obama, who did nothing, except covering up with hot air coming out of his mouth the black reality that the Federal government coal is sold at less than 20% of what it costs (according to a study published in Science in December 2016). Now, in another orgasmic bout of hot air, Obama and Trudeau, less than a month from giving the reins to Trump, have barred drilling in the Arctic. Looks like Obama is suddenly waking up to the possibilities that being a US president brings.

The moral thing to do is to be informed, and to look, in particular, at hypocrisy with a clear eye. Now Obama will be able to claim that he stopped the pipelines and the drilling. Zorro arrived at the last second to save the Earth, seven and a half year too late. History will laugh at how naive his (frantically hypocritical) admirers were.

Patrice Ayme’

 

 

 

 

 

 

Antarctica Disintegrating Soon

December 9, 2015

[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.”

If One Looks Carefully, One Can See The Three Places Where Warm Water Is Sneaking In Below (In Green & Blue in WAIS and In East Antarctica).

If One Looks Carefully, One Can See The Three Places Where Warm Water Is Sneaking In Below (In Green & Blue in WAIS and In East Antarctica).

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.

http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=4347

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.

Weak Underbelly:

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…

Patrice Ayme’