Wind may be driving the melting of East Antarctica’s largest glacier

ScienceNews.com ^ | November 1, 2017 | Carolyn Gramling

[ETL]

If all of Totten Glacier’s ice slid into the ocean, global sea level would rise by at least 3.5 meters [~11.5 feet]

The wind is helping to awaken one of Antarctica’s sleeping giants. Warm ocean waters, driven inland by winds, are undercutting an ice shelf that holds back a vast glacier from sliding into the ocean, researchers report November 1 in Science Advances.

Totten Glacier is East Antarctica’s largest glacier, with a drainage basin encompassing about 550,000 square kilometers, an area about the size of France. Its floating front edge, the Totten ice shelf, sticks out like a tongue over the water and acts as a buttress for the giant glacier, slowing its movement toward the ocean. If the entire land-based glacier destabilizes and slips into the sea, it could raise global sea level by at least 3.5 meters.

Satellite and on-the-ground studies have previously shown that Totten Glacier and its buttressing ice shelf are thinning. Last year, scientists determined that the ice shelf is being melted from below by warm water. The ice shelf floats within a pool of its own cold meltwater that sits atop a deeper, saltier and warmer layer; the two layers generally don’t mix, like oil and water. The warmer layer periodically rises up, becoming shallow enough to access grooves in the seafloor that extend beneath the ice shelf. But what controls the inflow of that warm water was unknown.

Wind is the likely culprit, geophysicist Chad Greene at the University of Texas at Austin and colleagues now report. The researchers examined nearly 14 years of satellite observations of the ice shelf, comparing 629 pairs of images to track how its position and size changed during that time. Then, the team used surface wind and sea ice measurements over that same time period to create an almanac of changes in wind direction and intensity. Those wind patterns influence the movement of the water, not just horizontally, but also vertically: By pushing a mass of water in one direction, more water wells up from below to fill the void.

When the researchers compared the timing of upwelling ocean water with ice shelf changes, they found a pattern. About 19 months after the wind churned the ocean, cycling cold deep waters upward and sending the warmer surface waters down, the Totten ice shelf was noticeably thinner and had sped up.

Surface winds near the East Antarctic coast are expected to intensify in the next century due to warming. As a result, the ice shelf is likely to both thin and flow faster, the researchers note — and eventually, that could allow the glacier to slide into the sea.

“We have little data on the ocean and ice shelf conditions in this region,” says Fernando Paolo, a geophysicist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.  But the 14-year record used in the study is still somewhat short to infer a definitive link between wind-driven upwelling and ice shelf melt, he says. Still, he adds, these new data are a welcome addition to the pool of sparse observations, supporting the idea that Totten Glacier is very sensitive to changing oceanic conditions, much like the fast-thinning glaciers in West Antarctica.

Wind is the likely culprit, geophysicist Chad Greene at the University of Texas at Austin and colleagues now report. The researchers examined nearly 14 years of satellite observations of the ice shelf, comparing 629 pairs of images to track how its position and size changed during that time. Then, the team used surface wind and sea ice measurements over that same time period to create an almanac of changes in wind direction and intensity. Those wind patterns influence the movement of the water, not just horizontally, but also vertically: By pushing a mass of water in one direction, more water wells up from below to fill the void.

When the researchers compared the timing of upwelling ocean water with ice shelf changes, they found a pattern. About 19 months after the wind churned the ocean, cycling cold deep waters upward and sending the warmer surface waters down, the Totten ice shelf was noticeably thinner and had sped up.

Surface winds near the East Antarctic coast are expected to intensify in the next century due to warming. As a result, the ice shelf is likely to both thin and flow faster, the researchers note — and eventually, that could allow the glacier to slide into the sea.

“We have little data on the ocean and ice shelf conditions in this region,” says Fernando Paolo, a geophysicist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.  But the 14-year record used in the study is still somewhat short to infer a definitive link between wind-driven upwelling and ice shelf melt, he says. Still, he adds, these new data are a welcome addition to the pool of sparse observations, supporting the idea that Totten Glacier is very sensitive to changing oceanic conditions, much like the fast-thinning glaciers in West Antarctica.

[ETL]

[Steely Tom]

There was never wind before White American Males started driving big SUVs around.

[BlackVeil]

Glaciers always slide into the sea. We are supposed to act, now, like this is a new thing.

it could raise global sea level by at least 3.5 meters.

It could - or maybe it could not. This is like all their other dire predictions.

[ETL]

Oops! Just realized I screwed up a bit on the formatting. Repeated several paragraphs.

[Red Badger]

So, we need to break wind?....................

[ETL]

Glaciers always slide into the sea. We are supposed to act, now, like this is a new thing.
“it could raise global sea level by at least 3.5 meters.[11.4 ft]”
It could - or maybe it could not. This is like all their other dire predictions.

Yes, but they’re saying that this huge glacier (Totten) acts to hold back the entire ice sheet from sliding into the ocean. If it goes, so does the whole humongous ice sheet, so they claim.

[wmileo]

Goodbye to the left coasts.

[butlerweave]

WOW ,they know exactly what it will be like in 2070 .LOL

[Does so]

So, we need to break wind?....................

I'm disappointed that the original title of a new book describing in-flight refueling of aircraft was dropped.

The original name was "Passing Gas". :)

[lurk]

Ever notice how the very first sentence in every global warming article is so stupid you reflexively have some sort of physical response?

[ken in texas]

If it goes, so does the whole humongous ice sheet, so they claim.

Don't worry. I have a fancy computer model that predicts it will not happen. Trust me. /s

[bgill]

It’s all that hot wind blowing in from The Hill.

[EnglishOnly]

“Wind is the likely culprit”

Sounds to me like the Earth’s Wind is being altered by all these Windmills being put up.

Guess there’s only one thing to do: -— Tear down all the new Windmills and go back to the way things were without Windmills being used for power generation.

[ETL]

Ever notice how the very first sentence in every global warming article...

I don't necessarily take this as a pro global warming/'climate change' piece, although I'm sure the authors believe that that is the reason behind what is allegedly taking place there.

[editor-surveyor]

.
Massive BS!

Ice is rapidly increasing in Antarctica.

The ocean is impassable due to the ice.

.

[editor-surveyor]

.
Sea levels continue to fall, as they have since the early ‘80s.
.

[ETL]

...that is, unless the implication is that so-called “manmade global warming” is affecting wind currents in the region.

“the 14-year record used in the study is still somewhat short to infer a definitive link between wind-driven upwelling and ice shelf melt”

[ETL]

Massive BS! Ice is rapidly increasing in Antarctica.

But this piece has to do with one particular portion of Antarctica. Not the entire continent. A single glacier that is supposedly being undercut by *wind-driven* ocean upwelling.

[EXCH54FE]

OH play it again Sam, one more time with lots of DOOM & GLOOM.

“Surface winds near the East Antarctic coast are expected to intensify in the next century due to warming”, “If the entire land-based glacier destabilizes and slips into the sea, it could raise global sea level by at least 3.5 meters.”

Stop with all the “May” “Could” “Might” “expected”and all the other half Stepping. You are a geophysicist can you not state with some conviction that it “will” or “will not” occur within a time span that you FOOLS can measure and prove.

Don't forget winter is coming and colder temps "MAY, Could, Might" cause more ICE to form changing the direction of the winds or providing more COLD AIR forming more ICE.

[calenel]

Don't forget winter is coming

Winter in the northern hemisphere, but summer in the southern hemisphere.

For a whole host of reasons, though, they are still full of crap. Glaciers don't just fall off continents. Melting the leading edge of one won't make the rest of it come faster, and melting the submerged portion of one would actually lower sea level as the ice takes up more volume than the melt water it produces. Then overhanging parts might fall off, but not the whole glacier, pretty much keeping things the way they are.