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warmer air temps mean more antarctic sea ice


forkyfork

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i've been saying this on the forums for years and no one seems to pick it up. in a nutshell, the warmer sfc temps lead to a bigger gradient between the top of the ocean and the layers below, creating more stability and lessening the mixing of more salty water from below. fresher water is easier to freeze.

http://psc.apl.washington.edu/zhang/Pubs/Zhang_Antarctic_20-11-2515.pdf

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i've been saying this on the forums for years and no one seems to pick it up. in a nutshell, the warmer sfc temps lead to a bigger gradient between the top of the ocean and the layers below, creating more stability and lessening the mixing of more salty water from below. fresher water is easier to freeze.

http://psc.apl.washi..._20-11-2515.pdf

Then we should see this occur with the Arctic Sea Ice Extent as well, instead of just the Antarctic, but we don't observe this.

Hypothesis falsified!

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The Southern Hemisphere has been cooling at 0.05C/decade according to GISS since 2002, and 0.03/decade since 2000. The argument that warming has been causing increases in sea ice doesn't really hold water because that region is actually one of the fastest cooling on the entire globe. I believe the Southern Ocean and most of Antarctica, excluding the Antarctic Peninsula, have actually experienced a more drastic drop in temperatures than the GISS figures for the entire Southern Hemisphere that I quoted.

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The Southern Hemisphere has been cooling at 0.05C/decade according to GISS since 2002, and 0.03/decade since 2000. The argument that warming has been causing increases in sea ice doesn't really hold water because that region is actually one of the fastest cooling on the entire globe. I believe the Southern Ocean and most of Antarctica, excluding the Antarctic Peninsula, have actually experienced a more drastic drop in temperatures than the GISS figures for the entire Southern Hemisphere that I quoted.

What?

The arctic is currently on a yearly basis on GISS sitting above 2C+ anomaly's and your talking about fastest cooling stuff in the hundredths of degree's spectrum. I doubt a cooling in the hundredth's of a degree Celsius is having a big impact on anything.

Antarctic Surface temps anomaly's 1981-2010 climo the last year.

75-3.png

Antarctica surface temp's composite anomaly for 2007-2011 vs 1950-2000 anomaly for the same time period, which is the Southern Hemisphere solar blackout.

75-4.png

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What?

The arctic is currently on a yearly basis on GISS sitting above 2C+ anomaly's and your talking about fastest cooling stuff in the hundredths of degree's spectrum. I doubt a cooling in the hundredth's of a degree Celsius is having a big impact on anything.

Antarctic Surface temps anomaly's 1981-2010 climo the last year.

Antarctica surface temp's composite anomaly for 2007-2011 vs 1950-2000 anomaly for the same time period, which is the Southern Hemisphere solar blackout.

He's mostly referring to this:

13-monthly-southern-ocean.png

And your graph only shows that current temps are still higher than the 1950-2000 mean...it doesn't tell us what is going on the last ten years when most of the sea ice rise has occurred

1zd7yhg.jpg

I actually haven't read the paper yet so I cannot comment on it, but nzucker is right that there has been some significant cooling in the region. Its not uniform of course and it may be temporary, but its been there.

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You should also read the O'Donnell et al 2011 paper (in rebuttal to the Steig et al 2009 paper) on the Antarctic temperature trends.

Both of those papers were well after this one came out in 2006...and they are not in agreement with the NCEP maps.

oggdg8.jpg

Here are the satellite trends too

2rgdmy8.jpg

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Latest cop-out of the day! Meanwhile its -110 below zero in central Antarctica today.

Why not post your well researched well thought out analysis. Against Jinlun Zhang. Let's see first off what credentials he has.

Education

B.S. Shipbuilding & Ocean Engineering, Harbin Shipbuilding Engineering Institute, China, 1982

M.S. Ship Fluid Dynamics & Ocean Engineering, China Ship Scientific Research Center, 1984

Ph.D. Ice and Ocean Dynamics, Thayer School of Engineering, Dartmouth College, 1993

He has only had a PHD in Ice and Ocean Dynamics for 20 years. It has been roughly 7,300 days since Jinlun received his PHD that is a lot of time to continue to ascend his knowledge and perceptions of the craft.

Here is a photo of Mr. Zhang with is email and phone number, so he is transparent about contacting him about his work. You should take the time to email him about his COPOUT work he is doing as a PHD holder for 20 years in the field.

email address: [email protected]

Phone: 206-543-5569

zhang_jinlun.jpg

He is also the creator, I guess I should say co-creator of Piomas and many other projects. It's funny though he and his colleges created piomas and it turned out to be right. Pretty impressive among the list of things he has worked on.

Or you could read the paper or other papers on the subject and revise your COPOUT position on these highly accredited scientists.

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After reading the paper, they definitely use the NCEP reanalysis for surface temperatures in their study of 1979-2004 Antarctica trends as is cited by them more than once. The O'Donnell et al 2011 paper clearly differs from the NCEP reanalysis as shown in my previous post with the 1979-2003 trend they showed.

Its clear that in the O'Donnell et al 2011 temperature maps, the Antarctic region is not defined by a uniform significant warming in the peripheral regions of the Antarctic continent that is shown in the Zhang et al 2006 paper.

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Why not post your well researched well thought out analysis. Against Jinlun Zhang. Let's see first off what credentials he has.

He has only had a PHD in Ice and Ocean Dynamics for 20 years. It has been roughly 7,300 days since Jinlun received his PHD that is a lot of time to continue to ascend his knowledge and perceptions of the craft.

Here is a photo of Mr. Zhang with is email and phone number, so he is transparent about contacting him about his work. You should take the time to email him about his COPOUT work he is doing as a PHD holder for 20 years in the field.

email address: [email protected]

Phone: 206-543-5569

zhang_jinlun.jpg

He is also the creator, I guess I should say co-creator of Piomas and many other projects. It's funny though he and his colleges created piomas and it turned out to be right. Pretty impressive among the list of things he has worked on.

Or you could read the paper or other papers on the subject and revise your COPOUT position on these highly accredited scientists.

For one thing, the Antarctic area has cooled quite a bit more since his paper was published 6 years ago!

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For one thing, the Antarctic area has cooled quite a bit more since his paper was published 6 years ago!

I think his assumed (based on NCEP) trend from 1979-2004 was too warm to begin with anyway based on the O'Donnell et al 2011 paper. The satellite trends do not support the NCEP maps either...however, always some caution with those since its lower troposphere, but the Steig/O'Donnell papers seemed to place a more clear picture on the Antarctica sfc temperature trends.

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DISCLAIMER WHAT I POST BELOW IS LIKELY WRONG.

Here is my question. I know there has been cooling but. Southern Hemisphere Sea Ice has slowly gone up over the 34 years of dual band passive microwave. But the further we go back it was a lot cooler than now and the ice wasn't covering as much ocean as it is now.

seaice-15.png?t=1345334566

It was colder the further we go back. The ice area average was also lower. Since 1994 The southern ice has slowly grown and more recently has peaked up, but there is still a lot of natural variation vs the arctic which is to be expected because of the Earth's surface down there. the current high anomaly peaks are pretty inverse to the ones back in the 1980s but opposite.Both periods from 1979-1989 had wild fluctiations then 2001-current has also seen this. with a more steady period between them.

75-11.png

75-12.png

75-13.png?t=1345337140

75-14.png?t=1345337187

Could the shift in H5 anomalies which if I am on the right track would indicate more ridging over the land region because of increased heat flux upwards? Even if I am completely wrong on that, which is likely, wouldn't this indicate more blocking with the cold air dumping out of Antarctica.

75-15.png?t=1345337707

75-16.png?t=1345337800

75-17.png?t=1345337902

Again, I don't know much about it. But it would make sense to me if more PV intrusions from the Land Area continually move out over the waters they will cool and allow ice to form over larger regions away from the lower latitudes.

It also looks like more precipitation might be falling around and over the ice sheet during winter This might have an effect on the fresh water top layer for ice growth.

75-18.png

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DISCLAIMER WHAT I POST BELOW IS LIKELY WRONG.

Here is my question. I know there has been cooling but. Southern Hemisphere Sea Ice has slowly gone up over the 34 years of dual band passive microwave. But the further we go back it was a lot cooler than now and the ice wasn't covering as much ocean as it is now.

It was colder the further we go back. The ice area average was also lower. Since 1994 The southern ice has slowly grown and more recently has peaked up, but there is still a lot of natural variation vs the arctic which is to be expected because of the Earth's surface down there. the current high anomaly peaks are pretty inverse to the ones back in the 1980s but opposite.Both periods from 1979-1989 had wild fluctiations then 2001-current has also seen this. with a more steady period between them.

Do we know this for sure prior to the satellite era? Zhang's model showed a net increase in ice since 1948, but do we have observation confirmation for Antarctic sea ice since 1948 prior to the 1979 satellite era? This is an important question because the warming of Antarctica from 1948 is largely confined to the 1950s-1970s period and since then, not so much. So its possible there was more ice further back but we don't have confirmation and since the satellite era when the warming in Antarctica stopped, the ice has expanded in response to that as confirmed by satellites.

But I don't totally doubt Zhang's paper on increasing sea ice with warmer temps either...it seems to have validity...however, I'm just not sure its accurate to say there was less sea ice there in the 1950s-1960s or that its accurate to say its been warming since 1979.

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I was only referring to the satellite ERA. Not before. Unfortunately unlike the arctic the antarctic doesn't have anywhere near close the pre passive microwave data. There is data back to 1972 but that isn't much of a help.

I was just throwing out the argument that the land regions have warmed some equaling more ridging and more blocking lead to move cold intrusions from the land region into the Southern Ocean possible helping the ice growth.

But that is also under the assumption that the antarctic land region is warmer the last decade vs the 1979-2002 time.

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I was only referring to the satellite ERA. Not before. Unfortunately unlike the arctic the antarctic doesn't have anywhere near close the pre passive microwave data. There is data back to 1972 but that isn't much of a help.

I was just throwing out the argument that the land regions have warmed some equaling more ridging and more blocking lead to move cold intrusions from the land region into the Southern Ocean possible helping the ice growth.

But that is also under the assumption that the antarctic land region is warmer the last decade vs the 1979-2002 time.

Yes I'm not sure this correct. It might be...but its not currently supported by the O'Donnell et al paper outside of the peninsula. The Zhang et al paper assumes a lot of widespread warming on the periphery including the southern ocean that is also not supported by the O'donnell paper and also not supported by the SST reynolds data...its only supported by NCEP reanalysis.

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Yes I'm not sure this correct. It might be...but its not currently supported by the O'Donnell et al paper outside of the peninsula. The Zhang et al paper assumes a lot of widespread warming on the periphery including the southern ocean that is also not supported by the O'donnell paper and also not supported by the SST reynolds data...its only supported by NCEP reanalysis.

Regardless of the land temps, Friv could still be correct that a -AAO has allowed for more ice build-up in the surrounding seas like the Ross.

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Regardless of the land temps, Friv could still be correct that a -AAO has allowed for more ice build-up in the surrounding seas like the Ross.

Yes...but that would still fly in the face that the southern ocean has warmed like Zhang et al claims....whereas the other analysis shows it has not in the satellite era...esp recently.

But its still perfectly valid that warming may cause an increase in sea ice there too. Its just that the paper by Zhang may be incorrect in assuming warming has occurred where NCEP says it has because the O'Donnell paper says otherwise and so do satellites.

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Its interesting that the Zhang et al 2006 model shows an increase in Antarctic sea ice volume from 1948 too....yet nobody talks about the antarctic like we do with the arctic.

I'm not sure I believe the Zhang et al model though. As its assumptions seem to be very well challenged by the O'Donnell et al paper.

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Its interesting that the Zhang et al 2006 model shows an increase in Antarctic sea ice volume from 1948 too....yet nobody talks about the antarctic like we do with the arctic.

I'm not sure I believe the Zhang et al model though. As its assumptions seem to be very well challenged by the O'Donnell et al paper.

A lot of discrepancies to figure out.

NCEP re-analysis is way warmer than than the O'Donnell et al analysis, but there has been no response by NCEP to the O'Donnell et al 2011 claims.

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There is also a recent paper out that links winter warming in Western Antarctica to Central Tropical Pacific warming.

http://www.nature.com/ngeo/journal/v4/n6/abs/ngeo1129.html

The Pacific sector of Antarctica, including both the Antarctic Peninsula and continental West Antarctica, has experienced substantial warming in the past 30 years. An increase in the circumpolar westerlies, owing in part to the decline in stratospheric ozone concentrations since the late 1970s, may account for warming trends in the peninsula region in austral summer and autumn. The more widespread warming in continental West Antarctica (Ellsworth Land and Marie Byrd Land) occurs primarily in austral winter and spring, and remains unexplained. Here we use observations of Antarctic surface temperature and global sea surface temperature, and atmospheric circulation data to show that recent warming in continental West Antarctica is linked to sea surface temperature changes in the tropical Pacific. Over the past 30 years, anomalous sea surface temperatures in the central tropical Pacific have generated an atmospheric Rossby wave response that influences atmospheric circulation over the Amundsen Sea, causing increased advection of warm air to the Antarctic continent. General circulation model experiments show that the central tropical Pacific is a critical region for producing the observed high latitude response. We conclude that, by affecting the atmospheric circulation at high southern latitudes, increasing tropical sea surface temperatures may account for West Antarctic warming through most of the twentieth century.

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