'Game changer' – Antarctic melt due to warm water, not air temperature

From the University of California – Irvine  something that pretty well makes Steig et al 2009 even more irrelevant, since in that paper they did a survey of air temperatures and then smeared them around the continent using some Mannian style math, which was later shown to be faulty by O’Donnell et al.

Steig_antarctic_temp_trends_fig1UC Irvine found that ocean currents cause most of the observed melt, so air temperature really isn’t much of an issue.

Warm ocean drives most Antarctic ice shelf loss, UC Irvine and others show

Findings are a game changer for future forecasts about thawing continent

Irvine, Calif. – Ocean waters melting the undersides of Antarctic ice shelves, not icebergs calving into the sea, are responsible for most of the continent’s ice loss, a study by UC Irvine and others has found.

The first comprehensive survey of all Antarctic ice shelves discovered that basal melt, or ice dissolving from underneath, accounted for 55 percent of shelf loss from 2003 to 2008 – a rate much higher than previously thought. Ice shelves, floating extensions of glaciers, fringe 75 percent of the vast, frozen continent.

The findings, to be published in the June 14 issue of Science, will help scientists improve projections of how Antarctica, which holds about 60 percent of the planet’s freshwater locked in its massive ice sheet, will respond to a warming ocean and contribute to sea level rise.

It turns out that the tug of seawaters just above the freezing point matters more than the breaking off of bergs.

“We find that iceberg calving is not the dominant process of ice removal. In fact, ice shelves mostly melt from the bottom before they even form icebergs,” said lead author Eric Rignot, a UC Irvine professor who’s also a researcher with NASA’s Jet Propulsion Laboratory in Pasadena. “This has profound implications for our understanding of interactions between Antarctica and climate change. It basically puts the Southern Ocean up front as the most significant control on the evolution of the polar ice sheet.”

Ice shelves grow through a combination of land ice flowing to the sea and snow falling on their surfaces. The researchers combined a regional snow accumulation model and a new map of Antarctica’s bedrock with ice shelf thickness, elevation and velocity data captured by Operation IceBridge – an ongoing NASA aerial survey of Greenland and the South Pole. (Rignot will host a planning session of Operation IceBridge scientists at UC Irvine on June 17 and 18.)

Ocean melting is distributed unevenly around the continent. The three giant ice shelves of Ross, Filchner and Ronne, which make up two-thirds of Antarctica’s ice shelves, accounted for only 15 percent. Meanwhile, less than a dozen small ice shelves floating on relatively warm waters produced half the total meltwater during the same period.

The researchers also compared the rates at which the ice shelves are shedding ice with the speed at which the continent itself is losing mass and found that, on average, the shelves lost mass twice as fast as the Antarctic ice sheet did.

“Ice shelf melt can be compensated by ice flow from the continent,” Rignot said. “But in a number of places around Antarctica, they are melting too fast, and as a consequence, glaciers and the entire continent are changing.”

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Other authors are Jeremie Mouginot and Bernd Scheuchl of UC Irvine and Stanley Jacobs of Columbia University. Funding was provided by NASA, the National Science Foundation, and the National Oceanic & Atmospheric Administration.

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S. Geiger

uh, doesn’t this play into the theory of the camp saying that recent energy gains have been realized by ocean warming instead of atmospheric warming?

David, UK

So I guess the solution is to cut those evil CO2 emissions then? You know, that same CO2 that has been proven by satellites and weather balloons to have zero correlation with world temps?

David, UK

Oh sorry, I take your point. Mustn’t forget Trenberth’s heat decided to bury itself in the ocean. Right.

dontdistortthescience

Any why exactly is the water warmer Anthony?

Jeff

The researchers combined a regional snow accumulation model and a new map of Antarctica’s bedrock with ice shelf thickness, elevation and velocity data captured by Operation IceBridge – an ongoing NASA aerial survey of Greenland and the South Pole.
——
snow accumulation MODEL …. lost me right there….what’s so difficult about taking direct measurements? (OK,it’s cold, but someone’s got to do it….).
Makes me think of the 50s and 60s….ooooohhh, the electronic brain said xyz … so it MUST be true…
Questionable data merged with (possibly) good data is still bad, or at the least, questionable.
Why is it when they shake trees in the science buildings/areas, only liberal arts majors fall out?
(Nothing against liberal arts, but there seems to be a distinct lack of reasonableness-checking along with the scientifiic method being left at home…..

Pamela Gray

So where did the warm water come from? You should be able to reverse the SST captures and trace the origins of that warm water.

rustneversleeps

Desperado. When will you come to your senses.
What a VERY odd stretch of this result, as the first commenter realizes. Carry on, I suppose.
Eppur si muove.

No actual measurements of either ice sheet melt by water or water temperatures. Their conclusion seems to be based purely on model outputs.

RACookPE1978

OKkkkkkkkkkkkkkkk.
So, just how much warmer is that ocean water supposed to be? Compare, for example, the temperature of water in – 1995, then again under the same ice area at the same time of year, in 2005 and 2013.
Read again the “rules” of what they “found” in this so-called study. The increased ice loss is said to be under the small ice shelves, not the 3 big ones.
Snow fall (and inland ice movement) are the sources of ice shelf mass? Didn’t these guys read about the Antarctic continent area is the driest in the world, with only a few cm of total precipitation a year? Where is this snow fall they claim?

DesertYote

dontdistortthescience says:
June 13, 2013 at 5:29 pm
Any why exactly is the water warmer Anthony?
###
What ever the reason, it has nothing to do with atmospheric CO2. That would be like towing a semi-trailer with a moped.

Steve

“a researcher with NASA’s Jet Propulsion Laboratory in Pasadena”
Obviously unqualified to talk about climate science or is there nothing new to discover in their own field /sarc

CodeTech

Honestly, this is getting ridiculous. “Ice is melting too fast”. Too fast for what? How can someone draw valid conclusions about the entire complex system by short term observations?
Why do people instantly conclude that because something is happening it has to be unusual, unprecedented, bad, harmful, dangerous, or anthropogenic? Why??? Is it really so difficult to see how this is the result of brainwashing?
Ocean circulation is NOT stable and eternal. Ocean streams and flows are just as varying and chaotic as atmospheric weather patterns. There happens to be a flow that’s bringing equatorial waters to an area that they don’t always go. BIG DEAL. If this is actually a cause for concern to you, you should be seeking competent medical help. I understand there are promising therapies to handle your panic attacks using SSRIs, coupled with some knowledge.
It’s interesting, and worth documenting, in fact it’s fascinating to watch the planetary thermal equilibrium system at work, but it’s definitely not something to be alarmed about.

Larry Kirk

Most probably natural warming being taken up by natural melting, both in the arctic and the Antarctic. But warming nonetheless. It is still interesting to wonder what is causing the system to warm a little, or at least retain a little more heat. And interesting too to wonder what might it might be like if most of the sea ice where no longer available to take up the additional heat from the oceans, as may well have been the case 9,000 years ago during the Holocene climatic optimum, (when sea levels round here appear to have been some two to four metres higher than at present, judging by the raised beaches, erosional cliff notches and inland strand lines it left along my bit of coastline, just down from my house).

Bob Tisdale does an excellent job of explaining the warming and cooling ocean currents, and I look forward to his analysis of this study.

GlynnMhor

It just means that the models are wrong again.
There will no doubt arise another model tweaked to try to duplicate these findings.
Like the epicycles of geocentric and heliocentric celestial mechanics, more and more tweaks needed to be added on.

rustneversleeps

@ majormike1
it’ll be something about “cycles” magically taking the overall heat-content stepwise upwards, from “internal variability”. It will have lots of charts as well.
Although this study about attribution of Antarctic ice sheet/shelf melt isn’t about Bob’s “stuff” really…

GlynnMhor says:
June 13, 2013 at 6:19 pm
It just means that the models are wrong again.

Yep. An occupational hazard when you use a conclusion to chase the data.

Steig et al modeled and extrapolated, they got it wrong.
Will they recognize this?

There is another potential game changer that went off earlier today. Several days ago, I had noted that 3 Aleutian/Alaska volcanoes were in different stages of eruption or pre-eruption. The Veniaminof volcano went off today and it,s plume is on a heading SSE. If the eruption continues and holds this heading, then it will be blowing a cover over the primary warm spot, +3.83, that is sitting in the North Pacific. Here is a link to a look at the activity….http://thewatchers.adorraeli.com/2013/06/14/veniaminof/.

As I recall, Tilsdale has provided explanations of the warm currents hitting a portion of the Antarctic where ice melt is occurring. The area is actually disjointed from the continent.
Those who mention Trenberth have misunderstood his whole schemata – the warm ocean water is DEEP, not anywhere near the surface melting any ice.

This reminds me of all the hue and cry over the Greenland melting. Yet if you look at the daily or weekly sst info over the last 6 months, much of Greenland had been surrounded for most of that time. Then over the last several months a cold flow has become dominant and warm waters have been mostly driven away from Greenland. That ‘accelerated’ glacier melt is likely to come to a stop soon.

Latitude

…and our planet is so fragile…a fraction of a degree
Currents change….things change…..get used to it! LOL
Can we send these guys to the Arctic?

arthur4563 says:
June 13, 2013 at 6:44 pm
—————————————-
That would be the West Antarctic Peninsula, which is the northernmost spot of the Antarctic continent. It still shows slightly warm, but only at the northern top of the peninsula. The entire continent, except for that portion, is surrounded by slightly cool water at this time. I read recently that there has been record cold or close to record cold down there in some spots, in the last 2 weeks.

Rod

So warmer waters responsible for most of the melting. The water is obviously not that warm because Antarctica ice extent is near record maximums.

CodeTech says:
June 13, 2013 at 5:53 pm
Honestly, this is getting ridiculous. “Ice is melting too fast”. Too fast for what? How can someone draw valid conclusions about the entire complex system by short term observations?
———————————————————————————————————–
Code Tech has the prime response “Too fast for what?”.

Richard M

Since Antarctica is gaining land ice overall you can only wonder what “the speed at which the continent itself is losing mass ” is supposed to mean. I suppose their paper was already in before the following referenced paper was published. The contradictions in climate science continue unabated.
http://joannenova.com.au/2013/04/antarctica-gaining-ice-mass-and-is-not-extraordinary-compared-to-800-years-of-data/

Chris B

rustneversleeps says:
June 13, 2013 at 5:39 pm
Eppur si muove.
—————
And so does the Sun.

dontdistortthescience says:
“Any why exactly is the water warmer Anthony?”
Ocean currents move around, that’s why.
Many of us have been saying what this article says for several years now: changing ocean currents, storms, water temperature, winds, and other external influences cause changes in polar ice cover. Nothing in the climate remains static for long.
Global CO2 has nothing to do with polar ice — or else Antarctica would also be losing ice mass. Instead, Antarctica is setting a new record for ice cover every year.
Arctic ice loss was the last twig the alarmist crowd was clinging to like a drowning man. Now that twig has become waterlogged; the last failed prediction of the CAGW crowd.
Alarmists have now been proven wrong about everything. At what point do they admit that their runaway global warming conjecture has been falsified? Or are they such religious True Believers that, like Jehovah’s Witnesses, they will never admit that they were ever wrong?

dontdistortthescience

“…changing ocean currents, storms, water temperature, winds, and other external influences cause” – OK, so what is driving those changes?
And how can you rule out CO2 and other GHG?

milodonharlani

DesertYote says:
June 13, 2013 at 5:49 pm
dontdistortthescience says:
June 13, 2013 at 5:29 pm
Any why exactly is the water warmer Anthony?
————————————————-
Possibly because of a doubling in the UV component of TSI.
But whatever it is, it definitely isn’t because of one more CO2 molecule per 10,000 molecules of dry air over the past 150 years.

The main problem with the article are “value statements” like the following, ““But in a number of places around Antarctica, they are melting too fast, ….”
Why is it too fast? Does it even mean anything that the ice melts faster in one area for a number of years due to a warm current? Is this a periodic cycle where the ice declines in one area for a period of time and then usually grows for a period of time? Overall, the Antarctic has been growing recently. In areas that the Antarctic is growing, would this author also write it is growing too fast at those areas?
As was mentioned in the prior comment, from the joannenova.com.au report on the Antarctic show that the continent changes all the time.
The writing of these authors is unscientific and more suited to an editorial than a science paper.

SAMURAI

WOW!! Mother Earth seeking equilibrium…We’re doomed, I tell you, doomed!!! sarc/off..
The Earth is merely getting rid of some the millions of quadrillions of BTUs stored in the oceans and the atmoshpere. This is accomplished through ocean evaporation, cloud formation which blocks solar radiation, altocumulus cloud formation which dumps copious amout of heat out to space, converts thermal energy into kinetic energy in the form of wind, lifting GIGATONS of water kilometers into the air and moving over 300,000,000 cubic miles of ocean water with ocean currents, melting polar ice, etc….
So what?
Earth’s climate is a chaotic, nonlinear, diffuse, decoupled, majestic and often terrifying process that isn’t dictated by the addition of a few hundred ppm of CO2.
Sure, from the empirical evidence to date, CO2 may: increase atmospheric temperatures by 1C/doubling, generate more rain, increase farmland by a few million KM^2 in northern latitudes, and increase crop yields by 50%/doubling, but again, so what? Aren’t all these climate changes net benefits to humanity?
The theory that reducing manmade CO2 can stop the climate from changing isn’t anthropogenic global warming, that’s anthropogenic hubris….
I’m done with these grant whores…. How do we pull the plug on this nonsense?

barry

Neither Steig nor O’Donnell discussed ice shelves or land ice, so I’m not sure why that work is part of this discussion. O’Donnell et al criticised Steig and found that Antarctica was warming, but not as much.
http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3656.1
Of course, it is not axiomatic that because their results show less warming, their approach was better. Both results confirm warming land-surface temps over the Antarctic, so we can say that much with appropriate caveats.
As the researchers cited above talk about fast melting of the ice shelves, and the changing of the continental ice mass, in what way might this be a “game-changer”? Does giving primacy of cause to basalt melting change projections? Perhaps we’ll be able to discover this when the study comes online, which should be soon.
Here is the link to the article quoted in the top post here:
http://news.uci.edu/press-releases/warm-ocean-drives-most-antarctic-ice-shelf-loss-uc-irvine-and-others-show/

REPLY:
As is typical for you, you are being too literally dense. It applies because AGW zealots and media screamed that because the air temperature on Antarctica was going up, melt would occur, ice shelves would collapse.
For example, here it is claimed that the Larsen B ice shelf collapse due to warming air temperature.
http://www.climatehotmap.org/global-warming-locations/larsen-b-ice-shelf-antarctica.html
If they can make such comparisons, I can point out that air temperature is not the cause of melting, warm ocean currents are. Tough noogies if you don’t like the comparison, but turnabout is fair play. – Anthony

dontdistortthescience

[snip- its our old friend, Tom, the fake “moderate republican” under yet another fake name. You’ve been shown the door before – lets help you find it again. – mod]

dontdistortthescience

“But whatever it is, it definitely isn’t because of one more CO2 molecule per 10,000 molecules of dry air over the past 150 years.”
Sorry if I missed this bit, but where is it being argued that CO2 is the sole GHG contributing?

CodeTech

dontdistortthescience:
Don’t attempt to distort reality:
Nothing is CHANGING – just that things constantly CHANGE. See the difference?

dontdistortthescience

CodeTech – unless it is all supernatural magic things don’t just change. There has to be a drive of the change, just as there has been in the past and we are experiencing today. Unless you are saying that you believe in magic…

tjfolkerts

Desert Yote says: “What ever the reason, it has nothing to do with atmospheric CO2. “
It is always interesting to see people who are 100% sure of anything in climate science. Especially when pretty everyone else agrees that CO2 has some effect on the global temperatures.
“That would be like towing a semi-trailer with a moped.”
Or like towing a space shuttle with a pickup truck.
http://www.autoblog.com/2012/10/14/watch-a-toyota-tundra-tow-space-shuttle-endeavor/

otsar

Looks like they have discovered yet another stored and delayed release negative feedback mechanism.

David vun Kannon

Steig 2009 and this study are really apples and oranges, since the one is about continental temperatures and the other is about floating ice shelves.

bertie

I have said this many times in the past,these nutbars should be rounded up and sent to the arctic to live.They will be hoping for global warming after a few days.

R. Shearer

Judging by the Nature photo cover, it must be hot there…red hot.

bean

if you want to melt something, use a medium whose specific heat is 4 times more than air.

Mike H

“Any why exactly is the water warmer Anthony?”
I don’t know, but If Carl Wunsch from M.I.T. is correct, the cause occurred approximately 900 +/- 200 years ago.

Did the authors bother to check to see if the ice is actually melting? I mean…like, you know, it’s not really. http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.antarctic.png
But, if it was melting, that would be a reasonable explanation.

dontdistortthescience

Coverage and mass are two very different things James – are you saying that the ice mass for the whole Southern hemisphere is increasing?

barry

James, the research is about ice-shelves, not sea ice. The cryosphere data doesn’t apply.

REPLY:
As is typical for you, you are being too literally dense. It applies because AGW zealots and media screamed that because the air temperature on Antarctica was going up, melt would occur, ice shelves would collapse.
For example, here it is claimed that the Larsen B ice shelf collapse due to warming air temperature.
http://www.climatehotmap.org/global-warming-locations/larsen-b-ice-shelf-antarctica.html
If they can make such comparisons, I can point out that air temperature is not the cause of melting, warm ocean currents are. Tough noogies if you don’t like the comparison, but turnabout is fair play. – Anthony

JimF

Isn’t this the ultimate result of the processes Bob Tisdale and Willis Eschenbach have discussed here lately: heat from the equatorial Pacific Ocean being distributed to the poles through the action of the Nino-Nina cycle? We see high melting at both poles, but as a result of, among other things, warm water intruding into the ice-covered regions.

dontdistortthescience

JimF – what is driving the warming and changing currents, assuming it isn’t magic…

Janice Moore

Re: “… what is causing the system to warm a little… ” [post in above thread]
It might be less potentially misleading to say instead: “… what is causing this current pattern of energy transfer within the Earth’s climate maintenance mechanism…
There is no data that shows that the overall “system (of oceans – volcanoes – clouds – sun insolation, etc…)” is warming.

Larry Kirk

@ Tim Folkerts 7.54pm
Great shuttle photo! It’s not until you see it there, amongst the familiar clutter of a main street, that you realise just what an incredible beast it was, to be hurtling in through the upper atmosphere at re-entry speed, practically on fire from the friction, and then coast into land, unaided on a runway. Just looking at it makes you realise the risk. A long way from flint arrowheads and animal hides that species..

Larry Kirk

@ Janice Moore 8.47pm:
Correct me if I am wrong Janice, but my information is that there is clear evidence from satellite radar altimetry that there has been a very small but measurable increase in overall global sea level, which is probably indicative of additional heat within the system (giving rise to both slight thermal expansion of the oceans and some net addition of melt-water from land-based ice).
I don’t think there is any dispute over that. The Earth’s climate is not a closed system. At times there is more heat coming into it from the sun than at others, and at times there is also more heat retained by the system relative to that lost to space than at others. Hence constant natural climate change, ice ages, inter-glacial warm periods (including the current one, which was initially notably warmer than the present) and corresponding rises and falls in sea levels.
The only dispute is over the cause of the present slight warming. Is it entirely natural? Or is it in part something that we have inadvertantly caused, (e.g. by mass deforestation, industrial and domestic thermal emissions or by adding a small fraction to the concentration of some atmospheric gases)?
Lots of people on either side of the controversy are convinced that they are know and are right, and some get very hot-blooded about it. As far as I am concerned the jury is still out, and probably will be for a very long time. But if I was to make a guess, as a geologist I would guess that most of it is natural. Which is not to say that the ultimate result, one way or the other, mightn’t get a bit uncomfortable. But I’d rather be able to grow mangoes in my mum’s backyard in London than have to go looking for the remains of the house under several hundred metres of ice.
With regards,

Master_Of_Puppets

Rubbish.
Eric has been beating this particular dead horse for years and still gets very little mileage from all the hot air his little body can produce.
And the Antarctic sea ice extent area just keeps increasing and increasing and increasing and increasing … irrespective of a one foolish Mr. Eric Rignot.
Ah Ha ! AR5 Time Y’all !
Dance dance dance dance.

Claude Harvey

I don’t see a word about the chain of underwater volcanoes that line the vicinity of the ONLY stretch of Antarctic sea ice extent that is contracting and which have been particularly active in recent years. According to the satellites, overall Antarctic sea ice extent is growing and has been for some 40 years. As to the claim that overall “mass” is declining, I don’t recall any data showing what Antarctic ice mass has ever been in the past. Declining from what?

dp

dontdistortthescience says:
June 13, 2013 at 5:29 pm
Any why exactly is the water warmer Anthony?

Willis described this some days ago when analyzing el niño and la niña events.
http://wattsupwiththat.com/2013/06/08/decadal-oscillations-of-the-pacific-kind/