West Antarctic glacier loss appears unstoppable, study finds

May 12, 2014
A map of West Antarctica. Credit: Wikipedia

A rapidly melting section of the West Antarctic Ice Sheet appears to be in irreversible decline, with nothing to stop the entire glacial basin from disappearing into the sea, according to researchers at the University of California, Irvine and NASA.

The new study presents multiple lines of evidence – incorporating 40 years of observations – that six in the Amundsen Sea sector "have passed the point of no return," according to glaciologist Eric Rignot, a UC Irvine Earth system science professor who is also with NASA's Jet Propulsion Laboratory. The new study has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union.

These glaciers already contribute significantly to , releasing as much into the ocean each year as the entire Greenland Ice Sheet does. They contain enough ice to boost the by 4 feet (1.2 meters) and are melting faster than most scientists had expected. Rignot said the findings will require that current predictions of sea level rise be revised upward.

"This sector will be a major contributor to sea level rise in the decades and centuries to come," Rignot said. "A conservative estimate is that it could take several centuries for all of the ice to flow into the sea."

Three major lines of evidence point to the glaciers' eventual demise: changes in their flow speeds, how much of each glacier floats on seawater, and the slope and depth below sea level of the terrain they're flowing over. In a paper published last month, the research group showed that the speed at which the glaciers are moving has accelerated steadily for four decades, increasing the amount of ice draining from them by 77 percent from 1973 to 2013. This new study focuses on the other two lines of evidence.

The West Antarctic glaciers flow out from land over the ocean, with their front edges afloat. The point at which they lose contact with land is called the grounding line. Virtually all glacial melting occurs on the undersides of their floating sections – beyond the grounding line.

Just as a boat that's run aground can float again if its cargo is unloaded, a glacier can float over an area where it used to be grounded if it becomes lighter, which it does by melting or by stretching out and thinning. The Antarctic glaciers studied by Rignot's group have shrunk so much that they're now floating above places where they used to sit solidly on land, which means the grounding lines are retreating inland.

They're "buried under a thousand or more meters of ice, so it's incredibly challenging for a human observer on the surface to figure out exactly where the transition is," Rignot said. "This analysis is best done via satellite techniques."

The team used radar observations from the European Remote Sensing satellites (ERS-1 and ERS-2) between 1992 and 2011 to map the grounding lines' inland creep. The satellites employ a method called radar interferometry that enables scientists to measure very precisely – within a quarter of an inch – how Earth's surface is moving. Glaciers shift horizontally as they flow downstream, but their floating portions also rise and fall with changes in the tides. Rignot and his group mapped how far inland these vertical motions extend to locate the grounding lines.

The accelerating flow speeds and retreating grounding lines reinforce each other in a recurring loop. As glaciers move faster, they stretch out and thin, which decreases their weight and lifts them farther off the bedrock. As the grounding line retreats and more of the glacier becomes waterborne, there's less resistance underneath, so the flow accelerates, and so on – with each action intensifying the next.

Slowing or stopping these changes requires "pinning points" – bumps or hills rising from the glacier bed that snag the ice from below. To locate them, researchers produced a more accurate map of bed elevation that combines ice velocity data from ERS-1 and ERS-2 and ice thickness data from NASA's Operation IceBridge mission and other airborne campaigns. The results confirmed that just one pinning point remains upstream of the current grounding lines. Only Haynes Glacier has major bedrock obstructions upstream, but it drains a small sector and is retreating as rapidly as the other glaciers.

Bed topography is another key to the fate of the ice in this basin. All the glacier beds slope deeper below as they extend inland. As they retreat, they cannot escape the ocean's reach, and the relatively warm water melts them even more rapidly.

The accelerating flow rates, lack of pinning points and sloping bedrock all point to one conclusion, Rignot said:

"The collapse of this sector of West Antarctica appears to be unstoppable. The fact that the retreat is happening simultaneously over a large sector suggests it was triggered by a common cause, such as an increase in the amount of ocean heat beneath the floating parts of the . At this point, the end appears to be inevitable."

Explore further: New study shows major increase in West Antarctic glacial loss

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TegiriNenashi
1.8 / 5 (16) May 12, 2014
What "relatively warm water" are they talking about? If the authors of this study lift their heads [damaged by global warming hysteria] out of the sand, they would notice that sea ice around Antarctic is growing.
runrig
4.3 / 5 (16) May 12, 2014
What "relatively warm water" are they talking about? If the authors of this study lift their heads [damaged by global warming hysteria] out of the sand, they would notice that sea ice around Antarctic is growing.

You are aware that sea ice can form anywhere between Zero and -2C?
And therefore SST's could rise 2C and still form ice.
FFS.
supamark23
3.6 / 5 (17) May 12, 2014
What "relatively warm water" are they talking about? If the authors of this study lift their heads [damaged by global warming hysteria] out of the sand, they would notice that sea ice around Antarctic is growing.


Demonstrating yet again that stupid knows no bounds.
TegiriNenashi
1.6 / 5 (14) May 12, 2014

You are aware that sea ice can form anywhere between Zero and -2C?
And therefore SST's could rise 2C and still form ice.


Are you sure this subtlety works in your favor? Sea water becomes frozen at -2C ... so it requires lower temperature to form [compared to ice freezing at 0C at the Antarctic continent].

Let me reiterate the argument. Sea ice is forming as at the latitude as low as 58 degree south. [West] Antarctic ice shelves are located 72 degree and higher. Do you suggest that it is cold enough at 58 degree south, and yet at 72 degree the ice is melting?
supamark23
3.4 / 5 (18) May 12, 2014

You are aware that sea ice can form anywhere between Zero and -2C?
And therefore SST's could rise 2C and still form ice.


Are you sure this subtlety works in your favor? Sea water becomes frozen at -2C ... so it requires lower temperature to form [compared to ice freezing at 0C at the Antarctic continent].

Let me reiterate the argument. Sea ice is forming as at the latitude as low as 58 degree south. [West] Antarctic ice shelves are located 72 degree and higher. Do you suggest that it is cold enough at 58 degree south, and yet at 72 degree the ice is melting?


Why don't you drag your ignorant ass down there and measure it yourself? Otherwise, you're just running your fool mouth and need to STFU with your anti-science trolling.
TegiriNenashi
1.8 / 5 (15) May 12, 2014
Why don't you drag your ignorant ass down there and measure it yourself? Otherwise, you're just running your fool mouth and need to STFU with your anti-science trolling.


You mean like that infamous last year expedition stuck in the ice [the very disappearance of which it wanted to measure]? Once again, ice forming at 58 parallel, and disappearing at 72 -- do you have any explanation of this elementary and profound inconsistency?
Maggnus
4 / 5 (16) May 12, 2014
What "relatively warm water" are they talking about? If the authors of this study lift their heads [damaged by global warming hysteria] out of the sand, they would notice that sea ice around Antarctic is growing.
Back to zombie arguments again. Must we go through the difference between ice extent and ice volume with you again?

What is it with denialists and their zombie arguments? Pretending that it didn't get explained before and reposting the same garbage over and over seems to be the quintessential definition of insanity - if it wasn't true the first twenty six times it was posted, what ever makes you think it will be true the twenty seventh?

That, good people, is an example of argument by stupidity!

Maggnus
4 / 5 (16) May 12, 2014
Are you sure this subtlety works in your favor? Sea water becomes frozen at -2C ... so it requires lower temperature to form [compared to ice freezing at 0C at the Antarctic continent].

Let me reiterate the argument. Sea ice is forming as at the latitude as low as 58 degree south. [West] Antarctic ice shelves are located 72 degree and higher. Do you suggest that it is cold enough at 58 degree south, and yet at 72 degree the ice is melting?
What an excellent example of misunderstanding presented as meaningful dialog! Hint there skippy - you are not "reiterating" an argument, you are trying to reconstruct an already disproven strawman argument.

And around and around we go!
supamark23
3.7 / 5 (18) May 12, 2014
Why don't you drag your ignorant ass down there and measure it yourself? Otherwise, you're just running your fool mouth and need to STFU with your anti-science trolling.


You mean like that infamous last year expedition stuck in the ice [the very disappearance of which it wanted to measure]? Once again, ice forming at 58 parallel, and disappearing at 72 -- do you have any explanation of this elementary and profound inconsistency?


Again... present actual evidence to the contrary, or STFU. Look, everyone here knows you're an ignorant troll, paid to post misinformation about AGW on websites - it's actually pretty pointless to post your drivel here as the avg reader is far too well informed to fall for your lies. It's a pathetic way to make a living, and honestly you should be ashamed of yourself.
TegiriNenashi
1.3 / 5 (13) May 12, 2014
Must we go through the difference between ice extent and ice volume with you again?


Do you imply that ice extent, which is easy to measure with great accuracy, is increasing, and yet, the volume, which is hard to reliably measure, is decreasing? How convenient. If you challenge the simple idea that volume is much harder to estimate, why are there 20 competing ice extent maps/charts vs. a lonely ice thickness map
http://wattsupwit...ce-page/
TegiriNenashi
1.3 / 5 (15) May 12, 2014
Look, everyone here knows you're an ignorant troll, paid to post misinformation about AGW on websites - it's actually pretty pointless to post your drivel here as the avg reader is far too well informed to fall for your lies. It's a pathetic way to make a living, and honestly you should be ashamed of yourself.


It doesn't matter what "everyone here knows". If you are unable to refute elementary argument, your idea is impotent. And you insist defending flawed idea is honorable?
verkle
1.8 / 5 (13) May 12, 2014
With that much ice melting into the seawaters, it seems that it would have a global effect on cooling the oceans as it is melting.
RealityCheck
3.5 / 5 (11) May 12, 2014
What "relatively warm water" are they talking about? If the authors of this study lift their heads [damaged by global warming hysteria] out of the sand, they would notice that sea ice around Antarctic is growing.

The air can be freezing at the surface while the main body of water can be warmer below. Have you ever jumped in the pool on a 'cold-air-mass-day' so you can get warm because 'it's warmer in than out'?

The air from the interior antarctic comes out over the water and the air is cold because much of its heat has been transferred to the surface ice inland, and so freezes the ocean surface as that surface water transfers some heat to the cold air.

Its all in motion from one part of the system to another. You have to look at where the heat of air circulating from the tropics etc is being 'dumped', and where 'cold effects' are THEN felt when that cooled air mass heads back towards the tropics etc, along the way freezing surface water just off antactica coast. Complex. :)
aksdad
1.7 / 5 (12) May 12, 2014
They contain enough ice to boost the global sea level by 4 feet

Yes, but the relevant fact that it would take thousands of years at the current rate was left out. For example, from 2009:

http://news.psu.e...ce-sheet

Intentional? Of course. It paints an alarmist scenario, as the headline makes evident: "West Antarctic glacier loss appears unstoppable". It could easily (and more accurately) have read "West Antarctic glacier discharge increases since 1970".

Lots of glaciers have had faces retreat (by miles!) then advance as local (not global) climate changed: precipitation, temperatures, etc. It's unlikely the West Antarctic glacier mass loss is "unstoppable" as no one alive has a handle on century- to millenial-scale local (or global) climate trends.

On another note, TegiriNenashi is right about record sea ice around Antarctica:

https://www.ncdc....1401.gif
Caliban
4.8 / 5 (11) May 12, 2014
aksdad,

These new findings indicate that the ice-offloading is ACCELERATING.

This means that the timescale for sealaevel rise will have to be revised, and, indeed, in the article itself, they say on the order of a few centuries --not a thousand-- years. You can expect this to be revised downward going forward, as it is a positive feedback.

Additionally, there is the new finding of accelerating uplift in Northern Anarctica, which will further amplify this feedback.

And TugNads is correct in one particular, only. Sea ice is at record extent. But this says nothing of the total volume, and ignores the fact that it is entirely SEASONAL.

Meanwhile, the waters surrounding Antarctica continue to both warm AND rise.

This is dire news. If you live on a coastal plain or low lying river basin, I suggest you consider relocating to higher ground.
aksdad
1.4 / 5 (10) May 12, 2014
Utter nonsense, BaconBits. More like 10 inches by 2100 if current trends continue. The IPCC gives a range of 10 inches to 32 inches (2 ft 8 in) by 2100. There is no prediction of 10 to 20 feet. See IPCC Fifth Assessment (2014), Technical Summary, Table TS.1 (pg. 90).

It should be noted that the IPCC bases its scenarios largely on computer generated global climate models, all of which have been shown to be overstated in the last decade.

The current instrument measurements and trends can be found here:

From tide gauges, 2.8 ± 0.8 mm/yr (1993 to 2009):
http://sealevel.colorado.edu/content/tide-gauge-sea-level" title="http://http://sealevel.colorado.edu/content/tide-gauge-sea-level" rel="nofollow" target="_blank">http://sealevel.c...ea-level

From satellite altimetry, 3.2 ± 0.44 mm/yr (1992 to present):
http://sealevel.colorado.edu/

So using some simple math it would take:

-1,088 years to rise 10 feet at 2.8 ± 0.8 mm/yr or 2,176 years to rise 20 feet
-952 years to rise 10 feet at 3.2 ± 0.44 mm/yr or 1,904 years to rise 20 feet
Caliban
5 / 5 (10) May 12, 2014
Utter nonsense, BaconBits. More like 10 inches by 2100 if current trends continue. The IPCC gives a range of 10 inches to 32 inches (2 ft 8 in) by 2100. There is no prediction of 10 to 20 feet. See IPCC Fifth Assessment (2014), Technical Summary, Table TS.1 (pg. 90).

It should be noted that the IPCC bases its scenarios largely on computer generated global climate models, all of which have been shown to be overstated in the last decade.

The current instrument measurements and trends can be found here:

From tide gauges, 2.8 ± 0.8 mm/yr (1993 to 2009):


Repeating myself...yet again:

These new findings indicate that the ice-offloading is ACCELERATING.

Moreover, the same trend has been identified in North and East Antarctica, too, and all represent positive feedbacks, and none of which are accounted for in your outdated citations.

Get yourself up to speed or get lost.
jyro
2.3 / 5 (3) May 12, 2014
Unstoppable for 4 billion years, plan for it.
Bonnie_
1 / 5 (12) May 13, 2014
I enjoy reading the increasingly desperate claims of the global warming crowd, and the pretzel twists they put themselves into in order to continue to claim tax dollars. Meanwhile the rest of us have already figured out the hoax. If your income is dependent upon global warming alarmism, you should probably start working on your resume.
Uncle Ira
4.2 / 5 (10) May 13, 2014
I enjoy reading the increasingly desperate claims of the global warming crowd, and the pretzel twists they put themselves into in order to continue to claim tax dollars. Meanwhile the rest of us have already figured out the hoax. If your income is dependent upon global warming alarmism, you should probably start working on your resume.


I suppose that you the science-man Skippy? So Mr. Bonnie-Skippy how you figure this thing out you?
Bonnie_
1.4 / 5 (11) May 13, 2014
I don't know who Skippy is. I occasionally find comment threads like this one and enjoy watching the global warmists get taken apart by logic and science. To see Michael Mann revealed as a liar and a cheat and seeing the global warming crowd become a laughingstock has been a real pleasure. Yes, I'm a scientist. One whose income does not depend upon perpetuating a fraud.
runrig
5 / 5 (10) May 13, 2014

You are aware that sea ice can form anywhere between Zero and -2C?
And therefore SST's could rise 2C and still form ice.


Are you sure this subtlety works in your favor? Sea water becomes frozen at -2C ... so it requires lower temperature to form [compared to ice freezing at 0C at the Antarctic continent].

Let me reiterate the argument. Sea ice is forming as at the latitude as low as 58 degree south. [West] Antarctic ice shelves are located 72 degree and higher. Do you suggest that it is cold enough at 58 degree south, and yet at 72 degree the ice is melting?

Tegri baby...
Everytime you utter on here you spout bollocks.

Latitude has nothing to do with it. It is JUST a function of being nearby a vast cold continent. It is the frigidly cold offshore winds that form the ice - so waters nearby the sticky-out bit will form sea-ice in winter just as reliably as water next to the nipped-in bits. Comprede?
FFS.
runrig
5 / 5 (9) May 13, 2014
Why don't you drag your ignorant ass down there and measure it yourself? Otherwise, you're just running your fool mouth and need to STFU with your anti-science trolling.


You mean like that infamous last year expedition stuck in the ice [the very disappearance of which it wanted to measure]? Once again, ice forming at 58 parallel, and disappearing at 72 -- do you have any explanation of this elementary and profound inconsistency?


Yes - see my post and apply some science to your thinking - an oxymoron perhaps I know.
Uncle Ira
4.1 / 5 (9) May 13, 2014
I don't know who Skippy is. I occasionally find comment threads like this one and enjoy watching the global warmists get taken apart by logic and science.


Looks like you need the lessons for reading there Skippy. Most peoples is reading it different from you.

To see Michael Mann revealed as a liar and a cheat and seeing the global warming crowd become a laughingstock has been a real pleasure.


Well at least you don't mind being the punching line on the joke you. But who this Michael Mann-Skippy? Ol Ira can not find his name in this article. And when I googles him I can't find no article he wrote in two or one years.

Yes, I'm a scientist. One whose income does not depend upon perpetuating a fraud.


Are you the real scientist? Or just play the scientist on the internet forum? So far to now you haven't said nothing that sounds like the science-man-Skippy. So far to now you sound like the Obama-sock-Skippy.
runrig
5 / 5 (10) May 13, 2014
I don't know who Skippy is. I occasionally find comment threads like this one and enjoy watching the global warmists get taken apart by logic and science. To see Michael Mann revealed as a liar and a cheat and seeing the global warming crowd become a laughingstock has been a real pleasure. Yes, I'm a scientist. One whose income does not depend upon perpetuating a fraud.

I would suggest this experiment sunshine (hypothetically).
Get a gun with 3 bullets taken out of the 100 shot magazine and put the pointy end to your temple. Do you really think that 32:1 ratio is worth pulling the trigger on, no matter what the bet?
So with AGW climate science. It's blindingly obvious the vast majority of the world's experts have it wrong, either because of incompetence or through some grand socialist conspiracy/fraud. After all they are dripping in vast wealth. Stands to reason eh -they've all cheated at patience?
No it doesn't .... to anyone who is not clouded by ideological denial.
FFS
TegiriNenashi
1 / 5 (11) May 13, 2014
"...Latitude has nothing to do with it. It is JUST a function of being nearby a vast cold continent..."

If you imply that solar radiation doesn't depend on latitude, that is the most bizarre assertion I've read in this thread.

Egleton
2.3 / 5 (6) May 13, 2014
More like 10 inches by 2100 if current trends continue. The IPCC gives a range of 10 inches to 32 inches (2 ft 8 in) by 2100.

Eer. What is an inch? How much is that in vershok?
Captain Stumpy
4.6 / 5 (11) May 13, 2014
watching the global warmists get taken apart by logic and science
@bonnie come lately
I've been reading here longer than two years and commenting for a year and I have YET to see ANY empirical data shared that refutes global warming. please provide proof/links/data supporting your conjecture, because only a gullible scientifically illiterate person would fall for the anti-warming propaganda that gets posted here
showing ONE person to have lied is NOT showing where all the REST of the scientific community (97% approximately) has done anything wrong
Yes, I'm a scientist
until you can prove this, it is conjecture without evidence.

feel free to add empirical data, or links to studies from reputable sites
oh wait... there ARE NONE. that's right... that's why they use blogs here.

Runrig is a scientist too. as well as Tim Thompson. THEY PROVIDE LINKS AND PROOF. all you got so far is BS commentary, an not very good BS at that

thanks for playing.
runrig
5 / 5 (9) May 13, 2014
"...Latitude has nothing to do with it. It is JUST a function of being nearby a vast cold continent..."

If you imply that solar radiation doesn't depend on latitude, that is the most bizarre assertion I've read in this thread.


Look, were you borne obtuse or did you have to work at it?
Insolation has nothing to do with it either.
On June 22nd there is no sunlight from 66.5 deg S to the SP.
Insolation at just 8.5 north of there is negligible.
ALL that matters is the cooling effect of offshore winds.
I really don't know how to describe it in simpler terms - have you not noticed air spilling S over Canada from the Arctic into the US (I assume you are a citizen) in winter tends to be cold and will, like, freeze things. Sunshine will not melt it as the wet-bulb temperature is below freezing - that is the evaporation ( read sublimation ) will cool the ice to keep it frozen.
Without the Sun, heat/cold is ADVECTED and only heats from sensible heating via the surface it blows over.

ryggesogn2
1 / 5 (10) May 13, 2014
Norway's fjords used to be filled with glaciers.
Why did they disappear?

Runrig is a scientist too. as well as Tim Thompson.

To be precise, Runrig didn't claim to have a PhD (I'm sure he will correct me) and didn't Tim retire from JPL and if this is he, http://www.tim-thompson.com, he doesn't have a PhD or a degree in climate science.
To be fair, AGWites consistently assert the ONLY climate scientists can provide any critique of climate science.
And I am sure that anyone who doesn't have a PhD would be soundly rejected by AGWites in spite of the fact AGWites reject scientists with PhDs who have been in climate science for decades.
supamark23
4.1 / 5 (9) May 13, 2014
"...Latitude has nothing to do with it. It is JUST a function of being nearby a vast cold continent..."

If you imply that solar radiation doesn't depend on latitude, that is the most bizarre assertion I've read in this thread.



That's not the implication at all, only a moron would make that leap. So, why is Great Britain so much warmer in the winter than Canada? Leeds is at the same latitude as Edmonton, yet it doesn't go below freezing much... but Edmonton? Below freezing for several months each year. Oh, latitude doesn't actually determine temperature on its own. Please, do us all a favor and just go away. I mean, sure it's fun to belittle the moron posting nonsense but shooting fish in a barrel is only fun for so long...
supamark23
3 / 5 (6) May 13, 2014
Yes, I'm a scientist
until you can prove this, it is conjecture without evidence.

feel free to add empirical data, or links to studies from reputable sites
oh wait... there ARE NONE. that's right... that's why they use blogs here.

Runrig is a scientist too. as well as Tim Thompson. THEY PROVIDE LINKS AND PROOF. all you got so far is BS commentary, an not very good BS at that

thanks for playing.


He may, or not, be a scientist but one thing is for sure - he is several orders of magnitude more intelligent than you. Have a nice day.
Maggnus
5 / 5 (8) May 13, 2014
Do you imply that ice extent, which is easy to measure with great accuracy, is increasing, and yet, the volume, which is hard to reliably measure, is decreasing?
So we DO have to school you again! Yes, see: Sheppard et al (2012) http://www.scienc...11/1183, or review the data from GRACE, showing an accelerating volume loss, or the studies I linked you to the last time you made this same statement. That volume is harder to measure doesn't mean it can't be measured.
If you challenge the simple idea that volume is much harder to estimate, why are there 20 competing ice extent maps/charts vs. a lonely ice thickness map/
Because you linked to a denialist blog, and their denialism is easier to foist on the gullible when they show maps like that.

Hey, here's a thought! How about you look into the DATA yourself instead of relying on bloggers to tell you what to think?
TegiriNenashi
1 / 5 (10) May 13, 2014
So you have an explanation, and yet fail to predict where this trend [of increased sea ice cover] would stop? Besides, there are glaring contradictions in your story
http://takvera.bl...tic.html
Didn't you predict that polar amplification would decrease temperature difference between polar regions and equator? Where is this increased wind theory is coming from?
TegiriNenashi
1 / 5 (10) May 13, 2014
"...So, why is Great Britain so much warmer in the winter than Canada? Leeds is at the same latitude as Edmonton, yet it doesn't go below freezing much... but Edmonton? Below freezing for several months each year. Oh, latitude doesn't actually determine temperature on its own..."

No. You have sea ice boundary in Southern Ocean around Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous.
runrig
5 / 5 (9) May 13, 2014
Norway's fjords used to be filled with glaciers.
Why did they disappear?

Runrig is a scientist too. as well as Tim Thompson.

To be precise, Runrig didn't claim to have a PhD (I'm sure he will correct me) and didn't Tim retire from JPL and if this is he, http://www.tim-thompson.com, he doesn't have a PhD or a degree in climate science.
To be fair, AGWites consistently assert the ONLY climate scientists can provide any critique of climate science.
And I am sure that anyone who doesn't have a PhD would be soundly rejected by AGWites in spite of the fact AGWites reject scientists with PhDs who have been in climate science for decades.
Correct, I don't have a Phd - I was trained in-house after gaining relevant quals in Maths/Physics/Stats. I don't claim to be an exhaustive expert in Climate science - I am an expert in meteorology and that is it's cousin.
Re Glaciers in Norway having disappeared - you mught want to investigate THE major driver of climate - Mr Milankovitch
runrig
5 / 5 (9) May 13, 2014
"...So, why is Great Britain so much warmer in the winter than Canada? Leeds is at the same latitude as Edmonton, yet it doesn't go below freezing much... but Edmonton? Below freezing for several months each year. Oh, latitude doesn't actually determine temperature on its own..."

No. You have sea ice boundary in Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous.

FFS
Sea-ice forms in winter and melts in F*** summer - as does shelf ice!!!!!
Dr_toad
May 13, 2014
This comment has been removed by a moderator.
runrig
5 / 5 (9) May 13, 2014
So you have an explanation, and yet fail to predict where this trend [of increased sea ice cover] would stop? Besides, there are glaring contradictions in your story
http://takvera.blogspot.....
Didn't you predict that polar amplification would decrease temperature difference between polar regions and equator? Where is this increased wind theory is coming from?

It'll stop where it will stop - it matters not a jot as it's not caused by decreasing temperature.
Blogs aren't a source of unbiased science - merely biased opinion.
The idea of Polar amplification is correct - however Antarctica is not a typical pole.
I'll let you investigate why.
I've posted the reasons often enough.
Oh, and man has helped there too - with O3 depletion.
Antarctica is staying cold whilst the temperate zone is warming = increased density gradient = increased pressure gradient = increased winds + less convergent into the resident LP over Antarctica due strength negating frictional veering better.
rockwolf1000
5 / 5 (10) May 13, 2014
Anata wa oshiri desu, Tegiri. You and RigidSOB should have children.


Not possible. Each of them would just deny that the other exists.
thermodynamics
5 / 5 (9) May 13, 2014
Anata wa oshiri desu, Tegiri. You and RigidSOB should have children.


Not possible. Each of them would just deny that the other exists.


And not desirable. Can you imagine what the offspring would be like?
supamark23
4.6 / 5 (9) May 13, 2014
"...So, why is Great Britain so much warmer in the winter than Canada? Leeds is at the same latitude as Edmonton, yet it doesn't go below freezing much... but Edmonton? Below freezing for several months each year. Oh, latitude doesn't actually determine temperature on its own..."

No. You have sea ice boundary in Southern Ocean around Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous.


Wait, so now it is not latitude? Make up your mind... oh, wait... you're just pulling stuff out of your butt, sniffing it, then throwing it like a monkey in a cage.
Dr_toad
May 13, 2014
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (9) May 13, 2014
To be fair, AGWites consistently assert the ONLY climate scientists can provide any critique of climate science
@rygtard
I've never asserted this, but when it is explained by people IN THE FIELD like mentioned above, then you had better at least look at the data and UNDERSTAND IT before popping off at the mouth, as you are likely to look the fool, like you normally do. take THIS comment for instance
he doesn't have a PhD or a degree in climate science
ON http://www.tim-thompson.com/ there is this
I worked on the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) project
now READ TIL THE END... he worked with climate science
we were officially known as the Atmospheric Corrections Team
which again, makes you look stupid or illiterate http://www.tim-thompson.com/aster.html
plus, Runrig IS A METEOROLOGIST
AND he brigs empirical data NOT political party line crap with links to irrelevant poli-sci bull crap.
try learning to read/comprehend, Rygtard
TegiriNenashi
1 / 5 (9) May 13, 2014
Me: "You have sea ice boundary in Southern Ocean around Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous."

Supa: "Wait, so now it is not latitude? Make up your mind... oh, wait... you're just pulling stuff out of your butt, sniffing it, then throwing it like a monkey in a cage."

Do you have reading comprehension problems? 5 to 10 degrees north means exactly the difference in latitude.
Captain Stumpy
5 / 5 (8) May 13, 2014
Anata wa oshiri desu, Tegiri. You and RigidSOB should have children.
painful fetus exit strategy there. guess rygg would have to carry?
Me: "You have sea ice boundary in Southern Ocean around Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous."
runrig has explained this before, so between his explanations, the link here http://phys.org/n...ice.html and other studies in the mix, there is explanation. Physics works
there is plenty of information out there that is not on a conspiracy site that you can access.
Your sources also reflect on your argument.

Empirical data, studies from peer reviewed sources are best, and so on down the line, making blogs, conjecture, postings from unknowns with good "sound-bite" quotes and etc the last line and only valid to cranks.
TegiriNenashi
1 / 5 (7) May 13, 2014
"...runrig has explained this before...there is plenty of information...peer reviewed sources..."

Irrelevant. Examine average summer temperature map
http://en.wikiped...ture.png
and report back if you found location where it exceeds ice melting point. What does the paper that we are discussing suggests; that there is some evil warm current under sea ice pack which threatens to destabilize continental ice shelf?
supamark23
4.6 / 5 (9) May 13, 2014
Me: "You have sea ice boundary in Southern Ocean around Antarctic which is 5 to 10 degrees north of the continent boundary. The suggestion that sea ice is freezing up north and yet ice shelves are melting south is just ridiculous."

Supa: "Wait, so now it is not latitude? Make up your mind... oh, wait... you're just pulling stuff out of your butt, sniffing it, then throwing it like a monkey in a cage."

Do you have reading comprehension problems? 5 to 10 degrees north means exactly the difference in latitude.


You've yet to explain how two cities at the same latitude - Leeds, England and Edmonton, Canada - have such wildly different local climate. When you understand that, you'll understand why your statement about N vs S polar ice is so stupid. Or not, you are pretty stupid and may not even understand what I'm talking about.
supamark23
4.6 / 5 (9) May 13, 2014
"...runrig has explained this before...there is plenty of information...peer reviewed sources..."

Irrelevant. Examine average summer temperature map
http://en.wikiped...ture.png
and report back if you found location where it exceeds ice melting point. What does the paper that we are discussing suggests; that there is some evil warm current under sea ice pack which threatens to destabilize continental ice shelf?


lol, wait... I'm still laughing.... wait... still laughing... okay. So, peer reviewed sources are irrelevant but wikipedia isn't? Possibly the stupidest thing I've read in 2 weeks.
RealityCheck
4.3 / 5 (7) May 13, 2014
Hi all. :) I was already logged in attending to another matter, so....

@TegiriNenashi and others. :) West antarctic more island-like than continental-like; separated from most of antarctica by high mountain ridge.

Also it juts out into waters where its larger 'surface-to-mass' ratio allows more rapid exchange of heat than East Ant.

Also, warming ocean currents can reach more intimately close to more ice/cold mass/surfaces for more rapid heat exchange than in East Ant coast where incoming heat spread more slowly/thinly over longer less wrinkled coastal ice/cold mass/surfaces. See: http://en.wikiped...tica.svg

Half of ocean water at those latitudes washes around much smaller/rippled Western mass compared to larger/smoother Eastern half. So Western warms faster than Eastern.

Similar with Wind currents.

Related article: http://phys.org/n...tml#nRlv

Glacier accelerates if ice melting removes 'brake' at sea 'mouth'. :)
ryggesogn2
1 / 5 (7) May 13, 2014
he worked with climate science

So?
Runrig IS A METEOROLOGIST

So?
Stumpy asserted they were climate scientists, implying they rank with Judith Curry, Lindzen, John Christy, Pielke, Roy Spencer, ....all who have published, peer reviewed papers.

"Joe Bastardi, for example, a senior forecaster and meteorologist with AccuWeather, maintains that it is more likely that the planet is cooling, and he distrusts the data put forward by climate scientists as evidence for rising global temperatures. "
http://www.nytime...ing.html

These scientists disagree:
http://object.cat...mate.pdf
Why are Tim and Runrig correct?
Define 'consensus'. What percentage of 'climate scientists'? Who can be a 'climate scientist'? Any PhD who studies climate, someone with a BS in meteorology, ...?
ryggesogn2
1 / 5 (7) May 13, 2014
"A Nobel laureate has quit one of the world's leading organisations for scientists in protest at its assertion that the evidence of damaging global warming is "incontrovertible". "
"The US-based Norwegian physicist, who is the chief technology officer at Applied Biophysics Inc and a retired academic at Rensselaer Polytechnic Institute, the oldest technological university in the English-speaking world, added: "Global warming has become the new religion." "
""Global warming has become a new religion. We frequently hear about the number of scientists who support it. But the number is not important: only whether they are correct is important. "
http://www.telegr...est.html
But run and Tim know more than a Nobel prize winner in physics?
RealityCheck
3.3 / 5 (8) May 13, 2014
PS: @TegiriNenashi and others. Please listen closely and understand what supamark23 is trying to tell you about ALL the effective factors involved, including the ocean currents that determine local climes for whole regions/landmasses like UK (and West Antarctica too!, as per my post above).

If you don't understand what supamark23 is telling you, then ask questions of him on the details and I'm sure he will oblige IF you promise to listen and not just carry on in spite of information/explanation you may not have taken into account before you made up your mind up to now on partial/incorrect info from some political-shill blogger or other.

Good luck and good thinking, everyone! I probably won't be posting again unless I am really really forced to in the interests of science and fair play. Cheers and Bye all! :)
Caliban
5 / 5 (7) May 13, 2014
"...runrig has explained this before...there is plenty of information...peer reviewed sources..."

Irrelevant. Examine average summer temperature map
http://en.wikiped...ture.png
and report back if you found location where it exceeds ice melting point. What does the paper that we are discussing suggests; that there is some evil warm current under sea ice pack which threatens to destabilize continental ice shelf?


Dearest TugNads,

From your source:

"Data is the near-surface (1.5m) temperature from ECMWF 40 year reanalyses, for the period 1979-2001. There remain uncertainties in the values."

So, _approximately_ 0C, at a depth of 1.5m, from '79-'01.

Out of date and not sensitive enough to be conclusive in supporting what you hoped to assert.

That's a double-fail, moron.
TegiriNenashi
1 / 5 (9) May 13, 2014
...You've yet to explain how two cities at the same latitude - Leeds, England and Edmonton, Canada - have such wildly different local climate...


You must realize what assertion are you refuting here. "All places at the same latitude have the same temperature?" -- that is not what I said.

Take any geographic location. Now you move poleward 5-10 degrees. Do you expect the average temperature to increase? In order for your counterexample to work you must to find two cities at the same longitude.
TegiriNenashi
1 / 5 (8) May 13, 2014
"...Out of date and not sensitive enough to be conclusive in supporting what you hoped to assert..."

Find the one which supports your position, then. Do you challenge the simple idea that the ice pack boundary is rough approximation for -2C isotherm?
Caliban
5 / 5 (7) May 13, 2014
So then, rygsuckn', let's see their latest peer-reviwed publications.

What's that? There aren't any?

Of course not --you've just served up another steaming pile of dog's vomit from the Vault of Irrelevant Inanity.

Now do as all good doggies do.
Caliban
5 / 5 (7) May 13, 2014
"...Out of date and not sensitive enough to be conclusive in supporting what you hoped to assert..."

Find the one which supports your position, then. Do you challenge the simple idea that the ice pack boundary is rough approximation for -2C isotherm?


By your own logic, it could just as well be coterminous with +2C isotherm, you moron. And since you trotted out the claim AND the supposed supporting evidence for it, it's YOUR job to dig up the relevant factual data for said claim.

Another double fail for TugNads.
TegiriNenashi
1 / 5 (9) May 13, 2014
Do you challenge the simple idea that the ice pack boundary is rough approximation for -2C isotherm?


By your own logic, it could just as well be coterminous with +2C isotherm


-2C (i.e. -1.8 degrees Celsius) is freezing point of sea water. What +2C is supposed to represent?
Bonnie_
1 / 5 (15) May 13, 2014
The global warmist fanatics on this site have no idea who Michael Mann is? The infamous hockey stick hoax perpetuated by the IPCC?

Well I guess we could play a game to see if the kiddies here know how to look up "IPCC" on google.

I'm wasting my time here, but it was fun to pop in and see how low the intellect has fallen in the climate change debate. I'm relieved.
TegiriNenashi
1.4 / 5 (7) May 13, 2014
The global warmist fanatics on this site have no idea who Michael Mann is?


In the context of the article JH Mercer name is much more relevant. Here is James Hansen himself describing "John Mercer effect":
http://climateand...el-rise/
Uncle Ira
5 / 5 (7) May 13, 2014
Who Michael Mann is?


Well Mr-Scientist-Man-Bonnie-Skippy. Why you asking us that? It was you that brought him up. I still can no find him in the article up there.

Well I guess we could play a game to see if the kiddies here know how to look up "IPCC" on google.


It's a stupid game for you Skippy. I told you I look up the Michael Mann on the google, and everything they got is two or one year old, he ain't been around much. Maybe you should try something new.There is a lot of stuffs on the google that could bring you up to date.

I'm wasting my time here,


Skippy what kind of scientist man you are? It must not be much important if all got to keep you busy wasting your time with ol Ira. I'm not the really science man, peoples just make that mistake because I use the google when I want to say some science thing. Maybe if you wouldn't waste your times on one 3 or 2 year ago guy and spent more time reading the google you could say some science stuff.
runrig
5 / 5 (9) May 14, 2014
...Examine average summer temperature map
http://en.wikiped...ture.png
and report back if you found location where it exceeds ice melting point. What does the paper that we are discussing suggests; that there is some evil warm current under sea ice pack which threatens to destabilize continental ice shelf?

Tegri baby...

That map is an ave temp map, and so there will be some days, especially in mid-summer when temps will be higher (that's what an ave means).
Also around the continents periphery, especailly in the WAIS there will be incusions of more maritime air - which has a wet-bulb above 0C. Sunshine will act to melt the ice have an amplified effect by not being cooled to below zero via evaporation/sublimation. There will also be some rainfall at extremities which is a major melter of snow/ice. This is on the surface. The floating sheets are NOT being melted by an "evil warm current" - rather, it's just subtle warming.
runrig
5 / 5 (9) May 14, 2014
http://www.telegr...est.html
But run and Tim know more than a Nobel prize winner in physics?

Well the *Tory*graph would ...
One day you will apply logic and understand, that people, being people, bring many things into play in their decision making (may one of those be ideological bias?) and so, as you do, to expect 100% unanimity on the subject of AGW is beyond logical. NOTHING in life has unanimity of agreement where humans are concerned. And to argue, as you do, that because 1 Phd or 3% of science papers do not agree - that they are correct and the majority are wrong is a fail of truly epic proportions in critical thinking.
Maggnus
5 / 5 (7) May 14, 2014
Just to give some support to runrig's comment about the 3%, here is what the debate really looks like: https://www.youtu...GCJJUGsg
ryggesogn2
1 / 5 (11) May 14, 2014
And to argue, as you do, that because 1 Phd or 3% of science papers do not agree -

The history of science shows that real science advances when a minority disagree with the 'consensus'.
Also, in science, 'consensus' proscribes conformity and that is what AGWites are promoting, conformity.
If ANYONE does agree with them, they must be shouted down, expunged, ridiculed, attacked.
That is not science, that is religion, just as Giaever, and many others have stated.
TegiriNenashi
1 / 5 (11) May 14, 2014
That map is an ave temp map, and so there will be some days, especially in mid-summer when temps will be higher (that's what an ave means).
Also around the continents periphery, especailly in the WAIS there will be incusions of more maritime air - which has a wet-bulb above 0C. Sunshine will act to melt the ice have an amplified effect by not being cooled to below zero via evaporation/sublimation. There will also be some rainfall at extremities which is a major melter of snow/ice. This is on the surface. The floating sheets are NOT being melted by an "evil warm current" - rather, it's just subtle warming.


So, if temperature raises above freezing one day in summer, the whole antarctic west shield is in danger of collapse?
Maggnus
5 / 5 (10) May 14, 2014
So, if temperature raises above freezing one day in summer, the whole antarctic west shield is in danger of collapse?
Of course not, and what a pathetic attempt at a strawman argument! The ice sheet is in danger of collapse because it is flowing off the land faster and faster as the grounding line retreats. This is the result of warming ocean waters melting the glaciers from underneath. It says that clearly in the article, and even more clearly in the paper, if you would read it!

And you are back to the thin sea ice extent yet again! This has been explained to you several times, Denialist-Negator and yet you trot it out every time you post to one of these articles. Give your head a shake, your eyes have become stuck!
Maggnus
5 / 5 (7) May 14, 2014
And to argue, as you do, that because 1 Phd or 3% of science papers do not agree -

The history of science shows that real science advances when a minority disagree with the 'consensus'.
Also, in science, 'consensus' proscribes conformity and that is what AGWites are promoting, conformity.
If ANYONE does agree with them, they must be shouted down, expunged, ridiculed, attacked.
That is not science, that is religion, just as Giaever, and many others have stated.
Too bad you have no idea what you are talking about! Your cries of repression have become shrill indeed, and your lunatic paranoid ranting lunacy has descended into noise in the background. Your duplicity and obfuscation have become irrelevant to the conversation, and you're inane meanderings of New World Order conspiracies a laughing stock.

You are a paranoid loon.
supamark23
4.1 / 5 (9) May 14, 2014
...You've yet to explain how two cities at the same latitude - Leeds, England and Edmonton, Canada - have such wildly different local climate...


You must realize what assertion are you refuting here. "All places at the same latitude have the same temperature?" -- that is not what I said.

Take any geographic location. Now you move poleward 5-10 degrees. Do you expect the average temperature to increase? In order for your counterexample to work you must to find two cities at the same longitude.


Well, it's actually warmer in Seattle in the Summer than San Francisco... and Seattle is 10 deg. farther North. You should really do some research before running your mouth, it'd make it less simple to see just how stupid you are.
Captain Stumpy
5 / 5 (8) May 14, 2014
So, if temperature raises above freezing one day in summer, the whole antarctic west shield is in danger of collapse?
@tegiri
this argument can be represented thus:
Maggnus
The ice sheet is in danger of collapse because it is flowing off the land faster and faster as the grounding line retreats. This is the result of warming ocean waters melting the glaciers from underneath. It says that clearly in the article, and even more clearly in the paper
Tegiri:
I don't believe in science. Nu-uh! & my horoscope says I am right
P.S. Empirical data and science ALWAYS wins, tegiri. you should watch Maggnus video
global warmist fanatics on this site have no idea who Michael Mann is?
@head-up-your-bonnie
perhaps you should re-read all the above posts?
I'm wasting my time here
no. you wasted OUR time, with NO data/links/proof and only conjecture
see how low the intellect has fallen in the climate change debate
It will grow exponentially larger once you leave. THANKS
Captain Stumpy
5 / 5 (8) May 14, 2014
Stumpy asserted they were climate scientists, implying they rank with Judith Curry, Lindzen, John Christy, Pielke, Roy Spencer, ....all who have published, peer reviewed papers
@Rygg
this is the most insanely stupid thing you've ever wrote. You know as well as I that Mr. Thompson has peer reviewed papers out there... http://www.tim-th...rch.html guess you REALLY CAN'T READ!!!! I thought it a joke, but YOU REALLY CAN'T! wow!

tell you what, why don't you accuse him directly of being a fraud with no peer reviewed papers! You have his contact info!

@Everyone else, EXCEPT bonnie, rygg, tegiri, and stupidity et al
Sorry for being so snarky today.
runrig
5 / 5 (8) May 14, 2014
That map is an ave temp map, and so there will be some days, especially in mid-summer when temps will be higher (that's what an ave means).
Also around the continents periphery, especailly in the WAIS there will be incusions of more maritime air - which has a wet-bulb above 0C. Sunshine will act to melt the ice have an amplified effect by not being cooled to below zero via evaporation/sublimation. There will also be some rainfall at extremities which is a major melter of snow/ice. This is on the surface. The floating sheets are NOT being melted by an "evil warm current" - rather, it's just subtle warming.


So, if temperature raises above freezing one day in summer, the whole antarctic west shield is in danger of collapse?

Eer ... from the article...
""This sector will be a major contributor to sea level rise in the decades and centuries to come," Rignot said. "A conservative estimate is that it could take several centuries for all of the ice to flow into the sea.""
FFS
rockwolf1000
5 / 5 (9) May 14, 2014
@ Captain Stumpy

"@Everyone else, EXCEPT bonnie, rygg, tegiri, and stupidity et al
Sorry for being so snarky today."

No apology required.

Snarkiness is a direct and natural consequence of attempting a logical discourse with people whose brains atrophied long ago.
ryggesogn2
1 / 5 (7) May 14, 2014
So stump, peer reviewed papers, not a degree qualify one to be a 'scientist'?
But none of Tim's papers are on climate science.
Maggnus
5 / 5 (9) May 14, 2014
So stump, peer reviewed papers, not a degree qualify one to be a 'scientist'?
But none of Tim's papers are on climate science.
Begging the question, no doubt to set up some anti-socialist/lunatic fringe talking point.

I can also cherry-pick 3% of scientists who say the HIV virus was made to kill gay men. Your making of a strawman is recognized for the socialist ploy it is loon.

TegiriNenashi
1 / 5 (8) May 14, 2014
Well, it's actually warmer in Seattle in the Summer than San Francisco... and Seattle is 10 deg. farther North.


So, is average yearly temperature in Seattle higher than in San Francisco? We are talking climate here, so please spare me of weather anecdotes.
Maggnus
5 / 5 (9) May 14, 2014
Well, it's actually warmer in Seattle in the Summer than San Francisco... and Seattle is 10 deg. farther North.


So, is average yearly temperature in Seattle higher than in San Francisco? We are talking climate here, so please spare me of weather anecdotes.
Still belaboring the point? Do you even remember what the question centered on?
supamark23
4.2 / 5 (10) May 14, 2014
Well, it's actually warmer in Seattle in the Summer than San Francisco... and Seattle is 10 deg. farther North.


So, is average yearly temperature in Seattle higher than in San Francisco? We are talking climate here, so please spare me of weather anecdotes.


Move the goalposts much? You asked where on the same longitude it could be warmer closer to the pole, and I gave you an example. I win, you lose, STFU and accept that you're the loser. Again.

You must get paid by the post, regardless of content.
TegiriNenashi
1.3 / 5 (8) May 14, 2014
"Still belaboring the point?"

In the context of glacier formation the fact that you can have a day or two (or even whole month) above freezing temperatures is irrelevant. Thus the emphasis on yearly average temperature. However, if you (and your comrade) dismiss the simple idea that sea ice cover is a faithful representation of -2C isotherm, which is located 5-10 degrees north of the "endangered" ice shields, then we reached impasse.
Maggnus
5 / 5 (9) May 14, 2014
In the context of glacier formation the fact that you can have a day or two (or even whole month) above freezing temperatures is irrelevant.
But you were not talking about glacier formation, you are talking about the formation and extent of sea ice around the continent.
Thus the emphasis on yearly average temperature.
Which is immaterial.
However, if you (and your comrade) dismiss the simple idea that sea ice cover is a faithful representation of -2C isotherm, which is located 5-10 degrees north of the "endangered" ice shields, then we reached impasse.
Lets focus here then. Can you expand on this "simple idea" as I am not catching what you are pitching.
supamark23
4.3 / 5 (11) May 14, 2014
"Still belaboring the point?"

In the context of glacier formation the fact that you can have a day or two (or even whole month) above freezing temperatures is irrelevant. Thus the emphasis on yearly average temperature. However, if you (and your comrade) dismiss the simple idea that sea ice cover is a faithful representation of -2C isotherm, which is located 5-10 degrees north of the "endangered" ice shields, then we reached impasse.


The only impasse is that you are unable, or unwilling, to do the basic work of understanding the topic. Of course we can't have an intelligent discussion when you aren't able to understand the topic.
TegiriNenashi
1.1 / 5 (9) May 14, 2014
...simple idea that sea ice cover is a faithful representation of -2C isotherm, which is located 5-10 degrees north of the "endangered" ice shields, then we reached impasse.
Lets focus here then. Can you expand on this "simple idea" as I am not catching what you are pitching.


What is the pivotal mechanism of the alleged West Antarctic ice shield disintegration? There supposedly is some mysterious warm current undermining glacier bed. This current has to travel 1000 miles under the sea ice cover, so I doubt that when it reaches its destination it's warm by any stretch of imagination. Moreover, with expanding sea ice cover, this current get's warmer causing "accelerated" ice shelf loss? That is absurd.
TegiriNenashi
1.1 / 5 (7) May 14, 2014
What is the pivotal mechanism of the alleged West Antarctic ice shield disintegration? There supposedly is some mysterious warm current undermining glacier bed. This current has to travel 1000 miles under the sea ice cover, so I doubt that when it reaches its destination it's warm by any stretch of imagination. Moreover, with expanding sea ice cover, this current get's warmer causing "accelerated" ice shelf loss? That is absurd.


Let me explain it in simpler terms. Several other phenomena should happen before we can seriously consider possibility of West Antarctic ice shield disintegration:
1. Average temperature in the region should rise. As of now, Antarctica is not merely cold place. It's frigid.
2. The sea ice cover should disappear for the summer, creating possibility for warm water to contact glacier bed.
RealityCheck
3.7 / 5 (10) May 14, 2014
@TegiriNenashi. :) Please be aware that there is always a 'last straw' condition where a system can be unbalanced and enter a new 'accelerating' stage. You don't have to remove all the ice at the sea mouth, just enough that it no longer balances or 'brakes' the glacier's current advance to its present 'disgorging/calving' rate there. Glaciers move faster or slower depending on all the factors involved. If just a little more heat incursions cause just a little more 'marginal difference' amount of melting beneath OR on surface of glacier, then extra meltwater percolating down/along the glacier bottom will 'lubricate' more, and so allow speeding up glacier motion to sea.

If BOTH things are happening (ie, less 'braking' ice at mouth; and more underside lubrication), then the glacier dynamics will result in faster discharge/calving rate, as observed elsewhere.

It's not as simple as you think, mate! Leave this one to those who know glacier dynamics/heat-transport/incursion etc. Bye. :)
Maggnus
5 / 5 (10) May 14, 2014
What is the pivotal mechanism of the alleged West Antarctic ice shield disintegration? There supposedly is some mysterious warm current undermining glacier bed. This current has to travel 1000 miles under the sea ice cover, so I doubt that when it reaches its destination it's warm by any stretch of imagination. Moreover, with expanding sea ice cover, this current get's warmer causing "accelerated" ice shelf loss? That is absurd.
And this statement clearly details your lack of understanding of global ocean currents. It's actually hard to know where to start, as you're misunderstanding is so profound.

Ok, start here to get an understanding of how currents actually work (hint - they aren't mysterious).( http://geography....nts.htm)
Look at these southern subpolar current maps: http://www.herbar...n-M.html
Realize that there is more water in one of those currents than all of the Earth's rivers combined. (cont)
Caliban
5 / 5 (9) May 14, 2014
Do you challenge the simple idea that the ice pack boundary is rough approximation for -2C isotherm?


Yes, I do, TugNads. the ice pack boundary can and frequently does correspond with the aforementioned "Grounding Line", ANY temp above freezing, or for the extent of the ice pack beyond which mechanical, wind/tide forces are sufficient to transport the ice away, and so, therefore:

By your own logic, it could just as well be coterminous with +2C isotherm


As for this last egregiously superfluous query:

-2C (i.e. -1.8 degrees Celsius) is freezing point of sea water. What +2C is supposed to represent?


I could, just to indulge you, play nice and say that +2 represents the boundary of ice extent for any reason besides temperatures at or above -2C....

BUT, instead-- let's just say that +2 represents the isoMORON, or, as it is sometimes known, the isoSTUPIDITY, where your microcephalus refuses to distinguish a known unknown from a willful disunderstanding.
TegiriNenashi
1 / 5 (6) May 14, 2014
"Ok, start here to get an understanding of how currents actually work (hint - they aren't mysterious).( http://geography....nts.htm)
Look at these southern subpolar current maps: http://www.herbar...n-M.html
Realize that there is more water in one of those currents than all of the Earth's rivers combined. (cont)"

Are you sure your links support your position? I checked both, and none refers to elusive current delivering warm water to West Antarctic Ice Sheet. Circumpolar current flows happily around the continent and exhibits no intention to deflect south (and destroy WAIS).
PinkElephant
5 / 5 (10) May 14, 2014
@TegiriNenashi,
Against my better judgement, I will pretend that I can reason with someone of your 'intellect'... here goes
Circumpolar current flows happily around the continent and exhibits no intention to deflect south (and destroy WAIS)
Check this slightly less oversimplified depiction:
http://www.parks..../acc.htm
When done, report on what you've found...
What is the pivotal mechanism of the alleged West Antarctic ice shield disintegration?
See RealityCheck's immediately preceding post to you (3 posts above mine, as I write this.) He basically has it right. (A loud OT spammer, but he did finally manage a good post, in the end...)
This current has to travel 1000 miles under the sea ice cover, so I doubt that when it reaches its destination it's warm by any stretch of imagination.
The ice cover acts as an insulator from cold air above. And the ocean current isn't warm per se: it's merely just slightly *warmer* than before.
PinkElephant
5 / 5 (10) May 14, 2014
So, start at equilibrium:

glacier growth rate = glacier calving rate ==> glacier is stable.

Now man messes with radiative balance, the Sun cooks the oceans, the oceans warm up just a fraction of a degree (so far). Ocean currents carry this extra heat everywhere (including to great depths and high latitudes). So:

1) warmer water arrives at bottom of glacier on the sea bed (note: not at sea surface!) where the glacier is anchored.
2) warmer water gradually erodes the bottom ahchoring of the glacier
3) glacier loses friction against ground, experiences greater tidal/wind stresses, begins to calve/flow faster
4) calving/flow rates exceed glacier growth/replenisment rate
5) glacier is losing mass; getting thinner
6) thinner glacier is more pliable, lifts more off the seabed, warm water penetrates further into anchoring, eroding more
7) glacier is experiencing even less friction, moving even faster
8) water keeps slowly growing ever warmer, by the way...

Rinse the above; repeat; etc.
Dr_toad
May 14, 2014
This comment has been removed by a moderator.
PinkElephant
5 / 5 (9) May 14, 2014
@TegiriNenashi,

One more thing. I can see you objecting that how can it be a warmer ocean should coexist with more surface ice. I'll give you an example from a commonly encountered phenomenon here in the real universe (I don't know if that ever happens in the alternative reality you inhabit, but bear with me):

1) make yourself a cup of piping-hot coffee
2) try to drink it -- ouch, boiled tongue
3) what to do? what if we ... blow on its surface? Eureka! Evaporative cooling FTW!! Suddenly the surface is cold-enough to sip -- despite the fact that the bulk of the coffee underneath is still scalding-hot.

Now, change of scale.

Southern ocean == big volume of water.
Southern ocean surface == not as big a volume of water.
Intensified circumpolar and Antarctic off-shore winds (driven by AGW & ozone hole, by the way!) ==> faster cooling of circumpolar ocean SURFACE ==> more ice formation (especially in winter)

BUT ... the bulk of the ocean underneath is still marginally warmer.
TegiriNenashi
1 / 5 (4) May 15, 2014
Check this slightly less oversimplified depiction:
http://www.parks..../acc.htm


This is good reference. However, it is vague on the issue in question: is there significant flow of warm water delivered to WAIS?

So, your (and RealityCheck's) main idea is that 0.1 degree Southern Ocean temperature increase
http://judithcurr...ainties/
is capable undermining WAIS? BTW, with sea ice extent growing this 0.1 degree increase is dubious itself.
PinkElephant
5 / 5 (9) May 15, 2014
So, your (and RealityCheck's) main idea is that 0.1 degree Southern Ocean temperature increase
http://judithcurr...ainties/
is capable undermining WAIS?
Firstly, your link provides no justification for your 0.1 degree figure. Here's a better reference:

http://www.enviro...rn-ocean

"Since 1950, the upper kilometre of the water column and densest part of Antarctic bottom water in the Weddell Sea warmed by 0.2°C at 700-1000 metres between 35°S and 65°S."

Here's another:

http://www.nature...671.html

"The record reveals a linear increase in annual temperature between 1958 and 2010 by 2.4±1.2 °C, establishing central West Antarctica as one of the fastest-warming regions globally."

Secondly, when you jolt a dynamical system out of equilibrium, depending on the dynamics, the ball may keep rolling downhill for a long time before it comes to a stop again (so to speak.)
runrig
5 / 5 (8) May 15, 2014
So, start at equilibrium:

glacier growth rate = glacier calving rate ==> glacier is stable.

Now man messes with radiative balance, the Sun cooks the oceans, the oceans warm up just a fraction of a degree (so far). Ocean currents carry this extra heat everywhere (including to great depths and high latitudes). So: ........................................


A really excellent post Pink.
Just read the follow up .... make it 2.
Well done.