Huge East Antarctic Glacier Especially Susceptible to Climate Impacts


March 25, 2020

Denman Glacier in East Antarctica

This photograph shows ripples in the surface of Denman Glacier in East Antarctica that throw shadows against the ice. The glacier is melting at a faster rate now than it was from 2003 to 2008

Credits: NASA

Denman Glacier in East Antarctica retreated 3.4 miles (5.4 kilometers) from 1996 to 2018, according to a new study by scientists at NASA’s Jet Propulsion Laboratory and the University of California, Irvine. Their analysis of Denman — a single glacier that holds as much ice as half of West Antarctica — also shows that the shape of the ground beneath the ice sheet makes it especially susceptible to climate-driven retreat.

Until recently, researchers believed East Antarctica was more stable than West Antarctica because it wasn’t losing as much ice compared to the glacial melt observed in the western part of the continent. “East Antarctica has long been thought to be less threatened, but as glaciers such as Denman have come under closer scrutiny by the cryosphere science community, we are now beginning to see evidence of potential marine ice sheet instability in this region,” said Eric Rignot, project senior scientist at JPL and professor of Earth system science at UCI.

“The ice in West Antarctica has been melting faster in recent years, but the sheer size of Denman Glacier means that its potential impact on long-term sea level rise is just as significant,” Rignot added. If all of Denman melted, it would result in about 4.9 feet (1.5 meters) of sea level rise worldwide.

Using radar data from four satellites, part of the Italian COSMO-SkyMed mission that launched its first satellite in 2007, the researchers were able to discern the precise location where the glacier meets the sea and the ice starts to float on the ocean, or its grounding zone. The scientists were also able to reveal the contours of the ground beneath portions of the glacier using data on ice thickness and its speed over land.

Vertically exaggerated image of the ground under Denman Glacier in East Antarctica

This illustration shows a vertically exaggerated image of the ground under Denman Glacier in East Antarctica, including a deep trough (blue area in the center) beneath its eastern flank.

Credits: NASA’s Scientific Visualization Studio

Denman’s eastern flank is protected from exposure to warm ocean water by a roughly 6-mile-wide (10-kilometer-wide) ridge under the ice sheet. But its western flank, which extends about 3 miles (4 kilometers) past its eastern part, sits over a deep, steep trough with a bottom that’s smooth and slopes inland. This configuration could funnel warm seawater underneath the ice, making for an unstable ice sheet. The warm water is increasingly being pushed against the Antarctic continent by winds called the westerlies, which have strengthened since the 1980s.

“Because of the shape of the ground beneath Denman’s western side, there is potential for the intrusion of warm water, which would cause rapid and irreversible retreat, and contribute to global sea level rise in the future,” said lead author Virginia Brancato, a scientist at JPL.

It will also be important, her colleague Rignot noted, to monitor the part of Denman Glacier that floats on the ocean, which extends for 9,300 square miles (24,000 square kilometers) and includes the Shackleton Ice Shelf and Denman Ice Tongue.

Currently, that extension is melting from the bottom up at a rate of about 10 feet (3 meters) annually. That’s an increase over its annual melt average of 9 feet (2.7 meters). It’s also greater than the average melt rate for East Antarctic ice shelves between 2003 and 2008, which was roughly 2 feet (0.7 meters) per year.

The team published their assessment on March 23 in the American Geophysical Union journal Geophysical Research Letters.

This project was funded by NASA’s Cryosphere Program and received support from the Italian Space Agency and the German Space Agency. Data and bed topography maps are publicly available.

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Stephen Richards
March 27, 2020 2:12 am

How the hell does ice melt rapidly at temperatures between -70°C and -20°C

Cathode Anode
Reply to  Stephen Richards
March 27, 2020 6:47 am

Vulcanoes, probably

NASA Discovers Mantle Plume Almost as Hot as Yellowstone Supervolcano That’s Melting Antarctica From Below

This is in addition to 47 already known about and eruption would melt more ice in region affected by climate change

Reply to  Cathode Anode
March 27, 2020 4:27 pm

Nope. Very little volcanic activity in East Antarctica. The volcanoes are in West Antarctica and the Transantarctic Mountains.

Reply to  Stephen Richards
March 27, 2020 4:26 pm

It doesn’t really melt, there or anywhere in Antactica. It breaks off and calves into the sea. Where it melts. Eventually. Some icebergs down there last for decades.

March 27, 2020 2:46 am

The picture is not dissimilar to sand in a desert, due to the action of wind.

Reply to  John
March 27, 2020 4:29 pm

It has nothing to do with wind. Those are shear zones. The ice flows much faster over the buried through.

March 27, 2020 3:12 am

This configuration funnel warm seawater….

there is for the intrusion of warm water….

which cause rapid and irreversible retreat….

Intention or inclinations have no home in scientific studies unless bounded by errors. Voodoo science, well……

Reply to  AleaJactaEst
March 27, 2020 8:04 am

Ever notice that everything that is “caused” by CO2 is irreversible?

john harmsworth
Reply to  AleaJactaEst
March 28, 2020 2:35 pm

All glaciers flow downward to a terminus, where they melt. This flow is caused by gravity, with the pressure generated by the weight of continual snowfall at the summit and across the surface of the glacier. Once the ice melts at the terminus, I suppose it can’t unmelt and is therefore “irreversible”. It certainly can, and almost certainly will be replenished. Without any reference to the rate of acculation above the terminus this unscientific assessment is a complete waste of grant money. Perhaps the dog ate his homework. That might be reversible, with no real harm done since it was dog$4!t to start with.

March 27, 2020 3:15 am

And again; the use of “could” and “can” is predominant.

Hence, this MAY sooner or later cause my gastritis (aka gas ride) to possibly run out of control

Reply to  Telehiv
March 27, 2020 8:31 pm

I noticed the same. Nothing definitive or measurable.

Brett Keane
March 27, 2020 3:20 am

Those winds are cyclical on several scales.
Brett Keane

Paul Stevens
Reply to  paul homewood
March 27, 2020 4:17 am

Exactly. Most of the ice lies below sea level. If it melted, it would stay exactly where it is, as opposed to rushing out to mingle with the water of the sea water.

Alasdair Fairbairn
Reply to  Paul Stevens
March 27, 2020 10:52 am

Yes and if it did melt it would cause a reduction in sea level as the ice occupies a greater volume than the liquid. The sea water would rush in to mingle with it; but I don’t think rush is the right word here.

Reply to  paul homewood
March 27, 2020 4:45 am

Thanks, Paul!

Ron Long
March 27, 2020 3:44 am

This NASA report is a classic example of Political Science, which is the new substitute for what used to be Science. There is spin placed on small tidbits of data, and all of the spin is in the Doomsday direction. The next glacial cycle of the Ice Age we live in will certainly reverse any real or imagined melting at Antarctica. The only useful data here is the comment that the prevailing “westerlies” are getting stronger. This is interesting to me as the prevailing westerlies in the middle of Argentina are getting weaker, and both central Chile and central Argentina are losing their protection against polar outbursts, putting harvests at risk. Here, El Nino is a good boy and Neutral is a disaster.

March 27, 2020 3:58 am

The Denman Glacier happens to be the location of a very deep canyon, under the ice. In fact, it is globally the lowest point on “land” not covered by liquid water, at 3,500 m (11,500 ft) below sea level.

So, it may be that parts of the glacier ice are closer to the mantle, which could cause melting of ice geothermally.

Here is a comprehensive (136 pages), but dated (1995), geological survey of the Denman glacier area.
J.W. Sheraton et al., “Geology of the Bunger Hills-Denman Glacier region, East Antarctica”, (1995)

There is a convenient chart on page 5 which shows the layout of Denman and Scott glaciers with respect to the surrounding features. Bunger hills to the east which can be seen on Google maps.,100.7836632,153790m/data=!3m1!1e3!4m5!3m4!1s0xade1ea8e3a16389b:0xd3b4d58e43aa7ed1!8m2!3d-66.75!4d99.5

Reply to  Johanus
March 27, 2020 8:33 am

“So, it may be that parts of the glacier ice are closer to the mantle, which could cause melting of ice geothermally.”

I would like to expand upon my comment above. There is extensive evidence of subglacier volcanic activity in West Antarctica:
“Hot rock and ice: Volcanic chain underlies Antarctica”

However, the Denman Glacier is on the opposite coast, in East Antarctica, where there is virtually no volcanism, because the lithosphere (“crust”) is older and thicker.

But I believe there may be elevated heat flux around the Denman Canyon, because the lithosphere is thinner and the presence of SO2, a possible indicator of surface volcanism in the local area atmosphere. Using the online meteorological tool we can easily see SO2 emisions in real-time over the entire globe. I check this frequently, and usually find SO2 emissions widespread over the WAIS (West Antarctic Ice Sheet) but hardly any in East Antarctic. Today I was snooping around with and found a very small SO2 plume (0.08 micrograms per cubic meter) near the Denman Glacier, just south of Bunger Hill. It is so small that you have to zoom in to see it, because it apparently occupies only one sampling grid square.,-66.481,100.467,10,m:OmaiXe

I marked the spot with a red marker on this satellite view of the glacier.'48.0%22S+100%C2%B041'49.2%22E/@-66.2762558,97.7374613,439887m/data=!3m1!1e3!4m5!3m4!1s0x0:0x0!8m2!3d-66.43!4d100.697

Carbon Bigfoot
Reply to  Johanus
March 27, 2020 2:05 pm

A complete analysis is available here:

Reply to  Carbon Bigfoot
March 27, 2020 6:36 pm

“complete analysis” of what?
I did not see any article referring to Denman Glacier. I see mostly articles about WAIS volcanism and one article on the King Baudouin “crater” in East Antarctic (about 3000 km from Denman), which made a claim about a ‘volcanic caldera’ causing the melt. But there are no reports of volcanoes, sub-glacial or otherwise, in that region. Seems like handwaving to me.
[I realize that my conjecture may also be ‘handwaving’, but it does not depend on the existence of a volcano, but only ‘thin-enough’ lithosphere under a deep ice-filled canyon, to allow heat flow to create a melt channel, which seems to be consistent with reported observations over the years.]

I sympathize with the need to eliminate political bias (of any creed) from science, but I do not think the ‘plateclimatology’ in its present format helps solve that problem.

Carbon Bigfoot
Reply to  Johanus
March 31, 2020 6:45 am

Johanus I presume that you did not read the entire 66 page analysis and the shit load of studies that support it. You’re like many commentators on these pages that can’t see the forest for the trees, or more appropriately, the massive geological forces that dwarf the Atmospheric-Bias Theory and its teeny weeny energy.

Reply to  Johanus
March 27, 2020 8:35 am

Interesting. Thanks.

Reply to  Johanus
March 27, 2020 12:33 pm

Looking at the satellite views of the Denman glacier (above) it is remarkable (to me) that the Bunger Hills are relatively ice-free. There is a lake filled with algae (called ‘Algae Lake’). How is that possible?

It seems that nobody really knows, according to the Wikipedia article

Bunger Hills, also known as Bunger Lakes or Bunger Oasis, is a coastal range on the Knox Coast in Wilkes Land in Antarctica, consisting of a group of moderately low, rounded coastal hills, overlain by morainic drift and notably ice free throughout the year, lying south of the Highjump Archipelago.[1] The reasoning behind the minute amount of ice in the area is still relatively unknown and remains under intense debate amongst scientists today.

The Bunger Hills are located with its center at 66°17′S 100°47′E, stretching from 65°58’S to 66°20’S and from 100°20’E to 101°28’E. The Bunger Hills are marked by numerous melt ponds and are nearly bisected by an east-west trending Algae Lake (also known as Lake Figurnoye). Mapped from air photos taken by the United States Navy Operation Highjump (1946-1947) and named by the United States Advisory Committee on Antarctic Names (US-ACAN) for Lieutenant Commander David E. Bunger, United States Navy, plane commander of one of the three USN OpHjp aircraft which engaged in photographic missions along most of the coastal area between 14 E and 164 E. David E. Bunger and members of his crew landed their airplane on an unfrozen lake here in February 1947.

The Bunger Hills are surrounded by glaciers. On the southeast the Bunger Hills is bordered by the steep slopes of the Antarctic ice sheet, on the south and west by outlet glaciers, and on the north by Shackleton Ice Shelf, which separates the area from the open sea. The ice-free area measures 450 km2 (174 sq mi), according to some sources even 750 or 942 km2 (290 or 364 sq mi) (though these latter values include a marine area not covered by continental ice or the Shackleton Ice Shelf). The topography is characterized by rugged hills, and there are many freshwater and salt lakes. The largest and deepest lake, Algae Lake (Lake Figurnoye) is 25 km (16 mi) long and up to 137 metres (449 ft) deep. The leader of Operation Highjump, Admiral Richard E. Byrd stated that the Bunger Hills was ‘…one of the most remarkable regions on earth. An island suitable for life had been found in a universe of death.’ [2]

In fact, when the Bunger Hills were first extensively explored and photographed in the 1940’s by an expedition led by Rear Admiral Robert Byrd, the popular press at that time began to refer to the place as ‘Shangri La’, a living paradise hidden behind ice and snow.

Is it possible that subglacier geothermal heat may offer an explanation to this mystery?

Reply to  Johanus
March 27, 2020 4:40 pm

More likely it has something to do with the presence of that very deep through. Such throughs always draw down the ice level nearby. Part of Andöya in Northern Norway in a similar position was never completely ice-covered during Last Glacial Maximum.

Steve Case
March 27, 2020 4:26 am

The glacier is melting at a faster rate now…“The ice in West Antarctica has been melting…If all of Denman melted…That’s an increase over its annual melt average… blah… blah… blah

It’s well below freezing nearly everywhere, nearly all of the time in Antarctica, the ice can’t melt. Antarctica may be losing ice, but it’s a function of how much snow falls and how much ice calves in to the sea decades or centuries later.

March 27, 2020 4:29 am

“vertically exaggerated”

So, I can ignore the graphic altogether.

“If all of Denman melted, it would result in about 4.9 feet (1.5 meters) of sea level rise worldwide.”

Another thing I can safely ignore — no evidence that such an event will happen in my lifetime, or several lifetimes.

Could, if, maybe, might — I am supposed to sacrifice everything that is based on what is, ruin the economy, give up reliable energy, for a potentiality, a hypothetical.

Such are the thoughts of totalitarians, I guess…

Clyde Spencer
Reply to  Matthew
March 27, 2020 9:48 am

And, if pigs could fly, we would all have to wear hats and ‘rain’ coats outdoors. What is the probability that all of Denman will melt? Speculation on possibilities, instead of providing probabilities, is not even poor science.

Reply to  Clyde Spencer
March 27, 2020 10:27 am

I know, right, Clyde? It is irresponsible sensationalism at best.

March 27, 2020 4:39 am

Virus data from gov is being treated like climate data. Manipulated.

Massachusetts man says on radio he’s positive for coronavirus, quarantined in Skowhegan

The Maine Center for Disease Control says the man’s case wouldn’t be counted for Somerset County, which remained at zero confirmed cases as of Thursday, because federal rules go by a person’s primary residence.

Robert Long, spokesman for the Maine Center for Disease Control, pointed out Thursday that federal rules dictate that confirmed cases should be listed by a person’s primary residence.

“If the man’s primary residence is in another state, he would be listed in that state, even if he was tested and is being cared for in Maine,” Long said by email. “The U.S. CDC has stated that tracking cases by the state of primary residence is the best system to ensure an accurate national count.”

… I also hear there are no cases in Antarctica and predict there will be none. Same with other flyover country where folks from NY, NJ and MA are fleeing to…

As a retired fire chief, this reporting is totally unacceptable. Like the non reporting of wind turbine fires.


Reply to  john
March 27, 2020 5:16 am
Reply to  john
March 27, 2020 6:35 am

John I’m sure they don’t talk about solar farm fires either. As the world knows Australia had significant fires recently, no reported solar damage, unlikely. They didn’t report damage after the hailstorms and floods either.

Reply to  john
March 27, 2020 8:08 am

The purpose of this rule is to prevent all the cases in a state from being reported as residing in the one or two biggest hospitals in the state.
Is it perfect? No.
Does it make sense? Yes.

Clyde Spencer
Reply to  john
March 27, 2020 9:56 am

The CDC presents data aggregated at the level of Health Service Area (HSA), which roughly translates to the location of hospitals that service the proximate population. COVID-19 cases should be reported according to the HSA in which a person is quarantined or being treated. Epidemiology is almost as bad as climastrology. It appears that the Peter Principle is alive and well in both disciplines.

March 27, 2020 4:44 am

“…could funnel warm seawater underneath the ice,
there is potential for the intrusion of warm water,
which would cause rapid and irreversible retreat, and contribute to global sea level rise in the future,” said lead author Virginia Brancato, a scientist at JPL.
…It will also be important, … to monitor the part of Denman Glacier that floats on the ocean,…
Currently, that extension is melting from the bottom up at a rate of about 10 feet (3 meters) annually. That’s an increase over its annual melt average of 9 feet (2.7 meters). It’s also greater than the average melt rate for East Antarctic ice shelves between 2003 and 2008, which was roughly 2 feet (0.7 meters) per year.”

Fantasies, bad analysis, gross assumptions, plea for guaranteed funding lead to lots of personal opinions masquerading as scientific conclusions with very little fact.

Their use of frightening postulations as their closure paragraph gives evidence to their not open minded research.
Researcher presumption for every aspect of their analysis is unprecedented melt, even if that melt is not previously identified.

This allows their conclusion that water fractions of a degree below freezing, “around -1 degrees Celsius”, allows/precedes catastrophic melt scenarios. A claim unsupported by water physical phase change diagrams:

Even their own description of the physical situation fails to support their assumptions.

New technology piled on top of previous assumptions, including tracking highly sporadic elephant seal feeding dives; which allows these researchers to presume ‘unprecedented’ melt cycles.
Of course, their assumed future warm water pulses are blamed upon assumed ‘climate change’ caused westerly driven warm water currents.

Typical NOAA confirmation bias.

March 27, 2020 4:50 am

Potential seems to be the adjective of choice.

Make’s a change from the usual if, could, might, may etc etc etc

Michael Talcott
Reply to  fretslider
March 27, 2020 10:30 am

The moon has the potential to liquefy the earth. It just has to dissipate most of its angular momentum.

March 27, 2020 6:33 am

So, freezing water expands, right? This massive glacier seems to extend far below sea level. It would seem that the sea level drop due to the ice melt below sea level might offset the rise from that above sea level!

But on another note, globalists with their totalitarian dreams have reason to fear very long term ocean level rise (although they cannot do squat about it, really, if it should occur)! Just think of the innovation that has occurred over the last 100 years as man thrived, particularly in free, capitalist countries! Who knows what man made wonders await over the next 100 years! However, if the globalists are successful in taking control of the world and squashing human spirit and innovation, the “new world” then becomes one big third world country! These globalists should be scared for their descendants – very scared!

Coeur de Lion
March 27, 2020 6:44 am

It’s very perplexing. Every time I dot the little ringy-dingy green cursor in all round the edges of Antarctica it’s way below zero everywhere with large minus numbers. In the middle it’s REALLY COLD. Take a look.

March 27, 2020 7:31 am

NASA — mission-creep much? Stick to your original purpose.

March 27, 2020 7:32 am

Team Apocalypse discovered a new toy.

Robert W. Turner
March 27, 2020 7:33 am

Magic thermal properties of CO2 allow it to teleport heat from the atmosphere to the deep ocean where it upwells around East Antarctica and causes average ice shelf thinning to increase from 9 feet to 10 feet per year. Ignore that recent period where Antarctic sea ice extent was higher than average, CO2 was transporting its heat to other parts of the deep ocean at that time.

March 27, 2020 7:49 am

ARTICLE: “Because of the shape of the ground beneath Denman’s western side, there is potential for the intrusion of warm water”

How long has the ground had that shape beneath Denman’s western side?

Reply to  Olen
March 27, 2020 4:45 pm

For many million years. It takes time for ice to create such a deep fjord. It probably started forming during the Oi-1 glaciation about 35 million years ago. Though there was quite likely a river valley there before that.

March 27, 2020 8:03 am

Even though they can’t actually measure any increase in temperature, they can see the huge impacts that increase is causing.

Mariano Marini
March 27, 2020 8:31 am

I’m not able to find some research about microwave from satellites and their power level at the earth surface. Can you give me one link at least?

March 27, 2020 9:03 am

Huge East Antarctic Glacier Especially Susceptible to Climate Impacts

impack global warming

March 27, 2020 11:27 am

No matter what it is, when it comes to climate change, it’s always, ALWAYS:

“worse than we thought”

“faster than we thought”

“faster than anywhere else” (This is the big one, because no matter where in the world you are, it’s happening faster there than everywhere else!)

March 27, 2020 11:53 am

However, the president could have written the comments, but this could rule out his re-election soon if the majority of people have a different opinion.

March 27, 2020 4:22 pm

It might be worth pointing out that according to another recent GRL paper the East Antarctic Ice Sheet is actually growing. As a matter of fact it is growing about as fast as the West Antarctic Ice Sheet is shrinking, so the AIS as a whole is currently stable.
Of course that’s not what they say in the abstract. There they say “A cumulative mass gain of 980 Gigatonnes in Queen Maud Land since 2009, however, led to a pause in the acceleration in mass loss from Antarctica after 2016”.
Of course that is not exactly a lie. The acceleration did pause. But you have to dig into the actual paper to find out that not only the acceleration but also the actual mass loss went to zero (Figure 1, right panel).

By the way I could have told them from just that air photo that there is a narrow, deep buried fjord beneath that glacier. How could it be otherwise with such a narrow ice stream with strong shear zones on both sides? And the narrowness of the fjord means that it won’t thave any major effect on the ice sheet.

Here is the most recent relief map of the bedock of Antarctica underneath the ice (Bedmap 2) :

comment image

If you look very closely a bit inland (to the left) of the “easternmost” (most right-hand) extremity of East Antarctica you will see a teeny weeny horizontal blue slightly crooked thingy. That is what this is all about.

The fact is that there is a serious dearth of potentially unstable glaciers in East Antarctica, so they have to make do with what little they can find.

March 27, 2020 8:47 pm

The Denman Glacier is in Queen Mary Land, at 66 degrees South Latitude. In other words, the northernmost point in the vast East Antarctica. Glaciers typically retreat because of Less Snow, rather than temps above melting except in the brief, cool Antarctic Summer.

“The Devil is in the details.” These people lie like rugs…

March 27, 2020 9:45 pm

Oh, goody. We’re doomed again.

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