Antarctica's floodgates crumbling; Southern Ocean belches CO2; Safe ice melts; Krill migrate south.

I keep vigil.

The vast continent at the bottom of the world is isolated from the rest of the land masses on earth. This isolation is also due to its long dark winters, ice-covered landscapes, snow storms with driving winds and bitter cold.

It is the largest source of long term sea level rise on earth with West Antarctica as the largest source of uncertainty in sea level rise projection.

East Antarctica, much larger than the western side of the continent, has ice that is flatter in the middle, steep on the edges — flows softly in the middle and flows faster at the edges.

West Antarctica is much different. Rather than a concave down shape, it has a concave up shape. The ice has high elevation in the interior and, near the coast it is flat. It is flat because the base is floating in the ocean.

The great ice sheet of W Antarctica has run over everything, it fills in the valleys and overruns mountain tops. The base of the ice sheet covers the ocean sea floor. Warming ocean water from climate change flows under the great W Antarctic ice platforms - creating channels that eat away at the bottom of the ice shelf, thinning it, resulting in deep rifts and, finally causing cracks and the collapse of large portions of marine glaciers. 

Nowhere is this more apparent than at Pine Island Glacier (PIG) and Thwaites glacier. Currently, the ice shelf has deep rifts and, instead of breaking off in a massive iceberg as in years past, instead has been found to be crumbling every couple of months or so.

In previous years a nation-size chunk of ice breaks off in a typical process. These large icebergs would not move until they were swept up in the current of the Amundsen Sea (it could take years), and into the ocean where it finally meets its end - stuck on the shoals of the graveyard of icebergs near St. George Island.

Below I provide a summary of a few of the changes unfolding in Antarctica.  

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Inspired by @StefLhermitte, I used @ESA_EO#Sentinel1 data to make this 18-month animation of Pine Island Glacier @AntarcticPIG. Find a hi-res version for download here: https://t.co/0fmiOhvXBq. Not long until the next calving event. pic.twitter.com/TNlDpuH05g

— Adrian Luckman (@adrian_luckman) January 25, 2019

Antarctica losing six times more ice mass annually now than 40 years ago

Irvine, Calif., Monday, Jan. 14, 2019 – Antarctica experienced a sixfold increase in yearly ice mass loss between 1979 and 2017, according to a study published today in  Proceedings of the National Academy of Sciences. Glaciologists from the University of California, Irvine, NASA’s Jet Propulsion Laboratory and the Netherlands’ Utrecht University additionally found that the accelerated melting caused global sea levels to rise more than half an inch during that time.

“That’s just the tip of the iceberg, so to speak,” said lead author Eric Rignot, Donald Bren Professor and chair of Earth system science at UCI. “As the Antarctic ice sheet continues to melt away, we expect multi-meter sea level rise from Antarctica in the coming centuries.”

Antarctic Sea Ice Dips to Record-Low Extent for Early January

Just two years after shrinking to its lowest extent ever measured, Antarctic sea ice may challenge that record a few weeks from now. This depletion comes just as scientists reported a harrowing sixfold increase in the loss of Antarctic land ice over the last 40 years. Unlike land ice, the loss of sea ice doesn’t contribute to sea level rise in itself, but it could help make some of Antarctica’s land ice more vulnerable (see below).

The extent of ice cover encircling the Antarctic coast began taking a nosedive in December, dropping even more quickly than usual for the time of year (late spring in the Southern Hemisphere). Since December 25, Antarctic ice extent has set calendar-day record lows every day for more than three solid weeks. Satellite-based records from the National Snow and Ice Data Center go back to 1979.

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To the south, Antarctic sea ice actually become slightly more extensive, about 1-2% per decade, from the 1970s into the early 2010s, a development that’s not yet fully understood. A majority of simulations carried out in support of the IPCC’s Fifth Assessment Report predicted that Antarctic sea ice coverage should have declined between 1979 and 2013. The actual observed increase wasn’t hugely significant, but it did lead to successive record-high extents in 2012, 2013, and 2014.

In a 2015 review paper published in Nature Climate Change, a group of Antarctic experts identified some factors that may have enhanced regional sea ice production in spite of global warming. These included: —stronger westerly winds ringing the continent —increased meltwater flowing into the Southern Ocean —a stronger prevailing low in the Amundsen Sea. This tends to favor cold offshore flow and enhanced ice production in the Ross Sea, with mild onshore flow and reduced sea ice in the Amundsen-Bellinghausen region.

Whatever its causes, the unexpectedly resilient Antarctic sea ice certainly wasn’t enough to make up for the myriad effects of planetary warming elsewhere. As Jeff Masters once put it: “Calling attention to Antarctic sea ice gain is like telling someone to ignore the fire smoldering in the attic, and instead go appreciate the coolness of the basement, because there is no fire.

More East Antarctica glaciers are waking up

If the thick ice cover over East Antarctica were to melt, it would reshape coastlines around the world through rising sea levels. But scientists have long considered the eastern half of the continent to be more stable than West Antarctica. Now new maps of ice velocity and elevation show that a group of glaciers spanning one-eighth of the East Antarctic coast has been losing some ice over the past decade.

In recent years, researchers have warned that East Antarctica’s Totten Glacier, an enormous ice sheet with enough ice, scientists say, to raise sea levels by at least 11 feet (3.4 meters), appears to be retreating, thanks to warming ocean waters. Now, researchers have found that a group of four glaciers sitting to the west of Totten, plus a handful of smaller glaciers farther east, are also losing ice.

Although ice loss in East Antarctica has the potential to reshape coastlines around the world through sea level rise, scientists have long considered it more stable than its neighbor, West Antarctica.  Now, new maps show that a group of glaciers spanning 1/8 of East Antarctica’s coast has begun to melt over the past decade, hinting at widespread changes in the ocean.

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The change doesn’t seem random; it looks systematic. And that systematic nature hints at underlying ocean influences that have been incredibly strong in West Antarctica. Now we might be finding clear links of the ocean starting to influence East Antarctica.

Massive ocean carbon sink spotted burping CO2 on the sly

The Southern Ocean is doing less to moderate global warming than scientists thought, the evidence is mounting that its influence on climate will grow during this century, says Joellen Russell, an ocean modeler at the University of Arizona in Tucson who heads SOCCOM’s modeling team.

The Southern Ocean is one of humanity’s allies, slowing global warming by absorbing heat and carbon dioxide from the atmosphere. But now researchers report that the choppy waters around Antarctica are also quietly belching out massive quantities of CO2 during the dark and windy winter, reducing the ocean’s climate benefit.

The scientists behind the work, presented this week at a meeting of the American Geophysical Union in Washington DC, say that the winter emissions reduce the Southern Ocean’s net uptake of CO2 by 34%, or more than 1.4 billion tonnes per year. That amount is roughly equal to Japan's annual carbon emissions.

“The Southern Ocean is still going to be important in the global carbon cycle,” says Seth Bushinsky, an oceanographer at Princeton University in New Jersey who is leading the study. “We’re just trying to understand exactly how and why.”

The ocean’s winter CO2 emissions, which were tracked by a fleet of robotic floats, occur when deep waters rise to the surface and release centuries-old carbon. This is part of a larger process of ocean circulation that moves heat and nutrients around the globe, but researchers have struggled to pin down precisely how the overall system works, in part because of a dearth of data.

Antarctic krill: Key food source moves south

Antarctic Krill.  

Krill are small, shrimp-like creatures that swarm in vast numbers and form a major part of the diets of whales, penguins, seabirds, seals and fish.

Scientists say warming conditions in recent decades have led to the krill contracting poleward.

If the shift is maintained, it will have negative ecosystem impacts, they warn.

Already there is some evidence that macaroni penguins and fur seals may be finding it harder to get enough of the krill to support their populations.

"Our results suggest that over the past 40 years, the amount of krill has, on average, gone down, and also the location of the krill has contracted to much less of the habitat. That suggests all these other animals that eat krill will face much more intense competition with each other for this important food resource," Simeon Hill from the British Antarctic Survey told BBC News.

Huge Lakes Thought to Be Hiding Beneath Antarctica's Ice Seem to Have Vanished

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Follow us down the SALSA borehole as we go 3500 ft through the Antarctic Ice Sheet into Mercer Subglacial Lake. The UV collar at the top of the borehole irradiates sources of contamination. Once at the lake, we see the transition between the water and the bottom of the ice sheet. pic.twitter.com/af8Yoh8hCM

— Salsa Antarctica (@SalsaAntarctica) January 21, 2019

An icy mystery brewing under Recovery Glacier in Antarctica has scientists scratching their heads. Where researchers once thought there was a network of under-ice lakes, there now seem to be none.  

Antarctic researchers have long believed that large lakes lie hidden beneath the glacier in East Antarctica, trapped between the base of the ice and the bedrock of the Antarctic continent. A new study, though, failed to find any evidence of such large bodies of water.

"They're probably not there," said the study leader, glaciologist Angelika Humbert of the Alfred Wegener Institute's Helmholtz Center for Polar and Marine Research in Germany.

This apparent lack of lakes is very weird. Without these bodies of water, researchers can't easily explain other observations made about the ice, like the pockets where the surface of the ice rises and falls in cycles or the glacier's flow toward the sea. [Photos: Meltwater Lake Hidden Under Antarctic Ice]

"It's hard to understand how it couldn't be water," said Ted Scambos, a research scientist at the Earth Science and Observation Center at the Cooperative Institute for Research in Environmental Sciences in Boulder, Colorado who was not involved in the new study.

Russia, China, Norway sink landmark Antarctic ocean reserve plan

Testing the waters: a young Emperor penguin takes the plunge. According to various sources, including Andrew Darby in the Sydney Morning Herald, China has declared plans for an unprecedented expansion of fishing for Antarctic krill, the crustacean at the heart of the polar food web. Krill underpin the survival of Antarctic marine life including whales, seals, penguins, seabirds, and fish. China plans a seven-fold expansion in their annual catch. eco

A proposal to create one of the world's largest marine reserves in a vast area of pristine Antarctic waters has been rejected, prompting concern among conservation groups about the ecosystem's future.

After two weeks of deliberations, Russia, China and Norway on Friday blocked the plan for a 1.8m square kilometres maritime protection zone in the Weddell Sea at a summit of the 25-member Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) in Hobart, Australia.

The proposed reserve, roughly five times the size of Germany, would have made the area in question a no-go zone for fishing and other commercial activities.

Antarctica's waters and landmass are home to penguins, seals, whales and huge numbers of krill, a staple food for many species, among other animals.

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"Twenty-two delegations came here to negotiate in good faith but, instead, serious scientific proposals for urgent marine protection were derailed by interventions which barely engaged with the science," she added.

Bengtsson accused Russia and China of using "wrecking amendments and filibustering" to reduce the time available for "real discussion about protecting Antarctic waters".