From Penn State
Underlying ocean melts ice shelf, speeds up glacier movement
Warm ocean water, not warm air, is melting the Pine Island Glacier’s floating ice shelf in Antarctica and may be the culprit for increased melting of other ice shelves, according to an international team of researchers.
“We’ve been dumping heat into the atmosphere for years and the oceans have been doing their job, taking it out of the air and into the ocean,” said Sridhar Anandakrishnan, professor of geosciences, Penn State. “Eventually, with all that atmospheric heat, the oceans will heat up.”
The researchers looked at the remote Pine Island Glacier, a major outlet of the West Antarctic Ice Sheet because it has rapidly thinned and accelerated in the recent past.
“It has taken years and years to do the logistics because it is so remote from established permanent bases,” said Anandakrishnan.
Pine Island Glacier or PIG lies far from McMurdo base, the usual location of American research in Antarctica. Work done in the southern hemisphere’s summer, December through January 2012-13, included drilling holes in the ice to place a variety of instruments and using radar to map the underside of the ice shelf and the bottom of the ocean. Penn State researchers did the geophysics for the project and the research team’s results are reported today (Sept. 13) in Science.
The ice shelf is melting more rapidly from below for a number of reasons. The oceans are warmer than they have been in the past and water can transfer more heat than air. More importantly, the terrain beneath the ice shelf is a series of channels. The floating ice in the channel has ample room beneath it for ocean water to flow in. The water melts some of the ice beneath and cools. If the water remained in the channel, the water would eventually cool to a point where it was not melting much ice, but the channels allow the water to flow out to the open ocean and warmer water to flow in, again melting the ice shelf from beneath.
“The way the ocean water is melting the ice shelf is a deeply non-uniform way,” said Anandakrishnan. “That’s going to be more effective in breaking these ice shelves apart.”
The breaking apart of the ice shelf in the channels is similar to removing an ice jam from a river. The shelf was plugging the channel, but once it is gone, the glacier moves more rapidly toward the sea, forming more ice shelf, but removing large amounts of ice from the glacier.
The melting of floating ice shelves does not contribute to sea level rise because once they are in the water, the ice shelves have already contributed to sea level rise. However, most of the Antarctic glaciers are on land, and rapidly adding new ice shelf material to the floating mass will increase sea level rise.
“Antarctica is relatively stable, but that won’t last forever, said Anandakrishnan. “This is a harbinger of what will happen.”
The researchers believe that the interaction of the ocean beneath the ice shelf and melting of the ice shelf is an important variable that should be incorporated into the sea level rise models of global warming. Other recent research shows that without the channelized underbelly of the ice shelf and glacier, melting would be even more rapid.
“The Antarctic has been relatively quiet as a contributor to sea rise,” said Anandakrishnan. “What this work shows is that we have been blind to a huge phenomenon, something that will be as big a player in sea level rise in the next century as any other contributor.”
Also working on this project were Tim Stanton, research professor, and William J. Shaw, research assistant professor, Department of Oceanography, Naval Postgraduate School; Martin Truffer, professor of physics, Geophysical Institute, University of Alaska, Fairbanks; Hugh Corr, British Antarctic Survey; Leo E. Peters, research associate, Kiya L. Riverman, graduate student, both of Penn State; Robert Bindschadler, emeritus scientist, NASA Goddard Space Flight Center; and David M. Holland, professor of mathematics, New York University.
The National Science Foundation, NASA and the Natural Environment Research Council, UK, supported this work.
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The article does quote Anandakrishnan as saying in part: “What this work shows is that we have been blind to a huge phenomenon…”
If they are missing volcanic activity, then I agree with him.
“We’ve been dumping heat into the atmosphere for years” and when (IMHO) you do that then you create a thermal low and draw in cooler air and therefore it gets cooler.WUWT !? Might work for fluids too…maybe not (heat of pressure?).
Thanks for the interesting articles and comments.
johanna says:
September 13, 2013 at 10:53 pm
“What rubbish! This paper highlights what is wrong with much of contemporary science… In observing and analysing the natural world, you need benchmarks, history, geography and a bunch of other things.”
Indeed. In post-modern science, one basically gets together with a bunch of other “scientists” and hashes out a scenario which everyone agrees appears plausible. Data which support the notion are sought, and those which do not are downplayed. The narrative is then declared immutable fact, to which only Neanderthal knuckle-draggers would object.
We have come full circle. In pre-modern science, the priests of the Church played out the same role. Today, the over-credentialed and under-educated priests of the soi disant scientific establishment have taken over the shop.
Perhaps it is volcanic activity, but it is also possible that the big G-stream in that area has changed its direction a little bit since 2008.
This is more ridiculousness. What a waste of everyone’s time.
Apparently we are all misguided according to Mr Lean
http://www.telegraph.co.uk/earth/environment/globalwarming/10307449/Global-warming-Will-the-truth-brave-the-cold-light-of-day.html
In the meantime Antarctic sea ice remains at or near all time record highs. Enough said.
Volcanic and hydrothermal activity is the cause – end of story.
GIGO
Marc77 says:
September 14, 2013 at 5:44 am
Also, how can water be warm enough to melt land ice and cold enough to produce a record amount of ice on the salty oceans at a latitude farther away from the pole?
There is a lot of upwelling of deep water around Antarctica driven by the katabatic winds that blow off the continent. This water is warm relative to surface water, and it cools as it flows outward from the continent, getting cold enough to form sea ice.
There is no real issue that the upwelling water will cause icesheet melt. The issue is whether this water is getting warmer, and as I said above there is no evidence this is the case.
The most likely explanation is that Antarctica is cooling, increasing the katabatic winds causing a greater volume of upwelling and increasing sea ice.
This explanation isn’t AGW compliant and is therefore rejected out of hand.
reading these responses to the findings of real scientists reminds me of how an 8th grade class reacted to scientific studies whose findings their parents disagreed with. People get frozen in
old time beliefs.
Weather science is a joke…..
” Work done in the southern hemisphere’s summer, December through January 2012-13,”
by the time these bozos get home, write up their paper……the weather changes and makes a damn fool out of all of them
..but it does prove a point, all they can do is extend trend lines
They forget the affect sub sea volcanoes have on ice shelves, there a more under sea active volcanoes in the world than land volcanoes. I don’t have the figures but if you Google ‘undersea active volcanoes’ you will note in the region of Italy and the area around the Greek islands, Crete there are many and land has been sinking for centuries. No ice there?
So, dumping heat into the atmosphere over the US and Europe, is going to melt Antartic ice because the ocean uptake is so rapid.
I’ll give this one ‘line ball’
Line ball fraud or line ball fraud. Take your pick.
regards
( I always believed heat rises into the atmosphere, some lost into space some used in cloud formation. The heat released in midland locales would never ‘smell’ the ocean.???)
“””So if 1 cubic kilometre of ice gets melted we will end up with 21.875 cubic kilometres of very cold, slightly less salty, water which will remain on the surface of the sea. That is enough cold water to cover the global sea area to a depth of 62 centimetres, over half a metre. “””
Really? So the total global sea surface are is about 33 600 km2.
“We’ve been dumping heat into the atmosphere for years and the oceans have been doing their job, taking it out of the air and into the ocean,” said Sridhar Anandakrishnan, professor of geosciences, Penn State. “Eventually, with all that atmospheric heat, the oceans will heat up.”
Considering the atmosphere is on average cooler than the oceans, I’d love to hear him expand on his understanding of how AGW works..
One if the biggest scandals of AGW is the disconnect with oceanography. There is a well established science of how climatic variation arises from ocean circulation patterns, especially the dominant ENSO dynamics. This provides sound underpinning for the null hypothsesis that 20th century climate change is simply normal climate variation / oscillation.
http://cpb.iphy.ac.cn/EN/article/downloadArticleFile.do?attachType=PDF&id=22907
http://grims-model.org/front/bbs/paper/gcm-1/CLM-GCM_1997-4_Nartin_P._Hoerling_et_al.pdf
http://web.yonsei.ac.kr/climate/board/4/20090612072138217_2009-2_TAC_An.pdf
http://lumahai.soest.hawaii.edu/MET/Faculty/jff/2004_02%20Nonlinearity%20and%20Asymmetry%20of%20ENSO.pdf
http://www.lasg.ac.cn/UpLoadFiles/File/papers/2006/2006-dws.pdf
http://o3d.org/web_db_data/articles/1995/Penland-1995.pdf
http://www.ldeo.columbia.edu/res/div/ocp/pub/cane/MunnichEtAl1990.pdf
However the AGW camp have simply decided to ignore this body of scientific research and regard the oceans as a passive puddle whose every change in temperature is directly dominated by atmospheric and solar input, practically in real time.
No new science is needed to refute the AGW lie. Its all there already in the scietific literature, all that is needed is joined up thinking and honesty and real thorough integrated scholarship about the issue, not ignoring the ocean. A good test of this is that, if current MSM journalists can understand a scientific theory, its probably wrong.
To my knowledge there’s no known physical mechanism how atmospheric heat could cause net warming of the ocean.
One could only wonder how somebody can become a geosciences prof when blatantly not understanding basics physics.
But considering the fact that even here we notoriously encounter fervent believers in a colder body warming a warmer one usually via the infamous atmospheric backradiation** I would rather think that for some becoming a prof of geosciences producing then ideas flagrantly violating basic laws of thermodynamics getting support for it from NSF, NASA etc. …and publicity from WUWT becomes sort of inevitable. We live in interesting times.
————-
**purportedly causing the ocean to warm, while they don’t even try to understand that the atmosphere is unable of net heating of the ocean, because having lower average temperature, and that the ocean surface warms far beyond the effective temperature because it has considerably lower emissivity than a blackbody due to refractive properties of the water/air interface which while having extremely low reflectivity (albedo) from outside, it has exceptional reflectivity in the direction from inside, and that it is indeed chiefly the ocean, the chief storage and source of heat on Earth, warmed directly by solar shortwave radiation, but not able to emit same radiation fluxes at its mid-IR spectras, gaining so considerably higher average surface temperature than has the surface air, which is also what causes considerable net warming of the air (not vice versa) -by radiation, latent heat of vaporization ascending up until released, etc., changing considerably atmospheric temperature profile, but never affecting the overal average temperature of the atmosphere as whole, which is the -18C as the Stefan-Boltzman law predicts and which in fact is the very surface of the Earth, when considered from other than an earthbound perspective.
..and please, I don’t deny here nor confirm the existence of atmospheric mid-IR radiation, I just deny the possibility it significantly warms the ocean – the sea is so opaque to mid-IR that it cannot significantly penetrate it more than fraction of milimeter under its surface skin (for 10 micrometer 288K spectrum the 150 micrometer layer of pure water has transmittance 0.00007 and even worse is salt water) – so only what it could significantly contribute there to is the surface water evaporation – sort of very powerful heat pump, transporting from the sea and land surfaces way up more than 30% of all the energy they receive from the Sun in form of shortwave radiation, getting the surface rid of heat amounts many orders of magnitude higher than we are “dumping” into the atmosphere.
The statements in the OP don’t make any sense. The atmosphere is heated from the bottom, as it is nearly transparent to sunlight. The heat comes from the ocean and the ground in the form of sunlight reflected as IR. More than that, the temperature at the ground or sea surface should be a lot higher but its cooled (equalized to atmospheric temps) by evaporation or evapo-transpiration. That’s why cooling the earth leads to drought and warming the earth leads to more precipitation and lucious and bountiful vegetation (oh, the horror of it!). We (humanity) haven’t been ‘dumping heat into the atmosphere’ if anything we have very minimally increased its CO2 content. And the oceans have not been ‘taking it out of the atmosphere into the ocean’ Come on! the oceans have been reflecting heat back into the atmosphere, and also heating the atmosphere through vapor releasing heat as it condenses in the atmosphere in the form of rain. In other words the oceans cool by heating the atmosphere, not the other way around.
http://theextinctionprotocol.wordpress.com/2013/09/16/scientists-find-potential-catalyst-for-earthquakes-on-u-s-east-coast/
this is very interesting and very relevant.
now we can assume all the heat we release is diving into the oceans, working its way into the sea floor and causing continental drift. Bloody humans.
regards.a
Undersea vents from subterranean volcanic activity warm the water. I thought everyone knew this.
There are more submarine active volcanoes than land volcanoes.
“””””……Gary Pearse says:
September 14, 2013 at 7:53 am
“The breaking apart of the ice shelf in the channels is similar to removing an ice jam from a river. The shelf was plugging the channel, but once it is gone, the glacier moves more rapidly toward the sea,”
No. No. Noooo. The floating ice does not retard the inexorable movement of the glacier behind it! These guys wouldn’t even make it as McIntyre’s “high school teachers” in an earlier generation……”””””
Don’t you know; it is those cruise ships tied up to the docks, in San Francisco, that is stopping all those buildings on Russian hill from sliding down into the Bay !!
What is it with CAGW alarmists? Are they simply staging a winner-take-all contest to see who can tell the biggest whopper? I keep wondering if the newbies are simply hanging their shingle out, in hopes someone with deep pockets will hire them to tell their lies for them?
“All the world’s a stage…” – eh?
Philip Bradley
Sept 14, 2013, 3:20 pm
Your explanation about Antarctic cooling and katabatic winds could also explain the apparent increase in recent years of incursions of Antarctic cold air into South America, some of these reaching as far north as the equator.
Can anyone explain to me how global warming can cause localised hot spots that disperse as shown by the NASA sea anomaly file AMSRE_SSTAn_M ?( thought this may have been superseded by now)
If nature has found a way to produce this sort of heat pump that moves widespread low temperature differences to local high temperature ones surely this should be the topic of research not climate at all.