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Antarctic Sea Ice Extent


Snow_Miser

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I've heard it on the news for several years.  The increase (about 0.1% / decade) is solid corroboration of the climate science prediction that Antarctic sea ice will slowly increase until mid-century and then begin to decrease.  Warming causing an increase in sea ice may be counter intuitive but the warming has brought increased winds (more polynyas) and increased precipitation (less saline surface waters), both of which increase sea ice production. Two papers worth reading on Antarctic sea ice are Zhang 2007 and Turner 2009.

 

Made after the fact...

Those studies, like many others, had a desired conclusion before they started.

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I've heard it on the news for several years.  The increase (about 0.1% / decade) is solid corroboration of the climate science prediction that Antarctic sea ice will slowly increase until mid-century and then begin to decrease.  Warming causing an increase in sea ice may be counter intuitive but the warming has brought increased winds (more polynyas) and increased precipitation (less saline surface waters), both of which increase sea ice production. Two papers worth reading on Antarctic sea ice are Zhang 2007 and Turner 2009.

 

Read the papers I posted. With just stratospheric ozone changes and GHG changes alone, CMIP5 models predicted a decrease in Antarctic Sea Ice over the last 30-40 years. Does this disprove a human contribution to warming? No, but it highlights another part of the climate system where our understanding is poor.

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Made after the fact...

 

 

Both of those papers are based on reanalysis temperature data (mainly NCDC) which is in disagreement with both O'Donnell et al 2010 and the satellite temperature data which shows Antarctica has not been warming during the time of increased sea ice extent. The southern ocean SST data also confirms any lack of warming down there with a pretty steep cooling trend in the satellite era.

 

So saying increased antarctic sea ice extent because of warming down there might be true...but it would not be accurate to say the last 30 years of obxervations support this hypothesis. A more interesting side effect of AGW which is briefly touched upon in the Turner et al paper is an increased cirumpolar current around Antarctica which could cause cooling in that region which is what satellite SST data shows in the southern ocean.

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  • 4 weeks later...

Highest extent EVER recorded. Still a good week+ left to add to this record.

 

Looks like NSIDC and excuse makers got their stories crossed up.

 

Stronger winds explain puzzling growth of sea ice in Antarctica

 

http://www.washington.edu/news/2013/09/17/stronger-winds-explain-puzzling-growth-of-sea-ice-in-antarctica/

 

From NSIDC:

 

Antarctic weather patterns in August were unusual. Contrary to a 50-year trend towards stronger westerly wind flow—a pattern associated with both ozone loss and increased heat-trapping gases in the atmosphere—August 2013 saw a period of very low westerly wind speed across the continent.

 

 

 

Back to the drawing board..

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Highest extent EVER recorded. Still a good week+ left to add to this record.

 

Looks like NSIDC and excuse makers got their stories crossed up.

 

Stronger winds explain puzzling growth of sea ice in Antarctica

 

http://www.washington.edu/news/2013/09/17/stronger-winds-explain-puzzling-growth-of-sea-ice-in-antarctica/

 

From NSIDC:

 

Antarctic weather patterns in August were unusual. Contrary to a 50-year trend towards stronger westerly wind flow—a pattern associated with both ozone loss and increased heat-trapping gases in the atmosphere—August 2013 saw a period of very low westerly wind speed across the continent.[/size]

 

 

attachicon.gifAnt.jpg

 

Back to the drawing board..

A bit of a slip by the writer of the narrative when stating: "This helps to highlight why scientists are more concerned by Arctic ice shrinkage than by Antarctic ice expansion."

Why would anyone be concerned with ice expansion....anywhere???

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A bit of a slip by the writer of the narrative when stating: "This helps to highlight why scientists are more concerned by Arctic ice shrinkage than by Antarctic ice expansion."

Why would anyone be concerned with ice expansion....anywhere???

 

 

I can think of a lot of reasons why. Read up on "the sea ice years" around iceland in the late 60s and early 70s. Was quite disruptive to supply ships getting there.

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I can think of a lot of reasons why. Read up on "the sea ice years" around iceland in the late 60s and early 70s. Was quite disruptive to supply ships getting there.

LOL, I'm sure the narrator really is concerned about antarctic ice expansion wrt shipping! ;)

 

I'll be interested to see the various spiins (on both sides) when AR5 is officially released.  It should be entertaining, at the very least!

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Wow, I haven't been paying attention to the Antarctic Ice this year - this is really impressive, and now the Arctic seems to be following suit.

 

 

Not even close to reality.

 

 

 

 

This is exactly what Wang said was happening.  Antarctic is torching.  With no consolidated PV.  Just a large HP over the land and multiple PV's rotating around the landmass. 

 

 

 

hnuotmz.png?1?4366

 

 

Some of the Ensemble members super tank the AAO.  The OP GFS keeps the large HP pattern in place and makes it stronger.  Probably going to see even more ice records get broke if that happens.

 

 

aao.sprd2.gif

 

 

 

 

 

 

 

aao.sprd2.gif

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  • 2 weeks later...

This is the first time I've seen the northern tip of the Antarctic Peninsula completely surrounded by solid ice; usually, the tip is exposed to the open ocean, even in the dead of winter, or there's fragmented low concentration ice between the Peninsula and Chile.

 

SSTs are also dropping rapidly to the east of the Antarctic Peninsula where some of the huge positive anomalies in sea ice are. There's a belt of generally below average SSTs around 60S, probably due to the impressive growth of the ice sheet with the -AAO coupled with the long-term cooling of the Southern Ocean which has been ongoing since the 1970s.

 

Overall very impressive to see signs of recovery on both sides of the cryosphere. We're probably looking at one of the best overall global sea ice anomalies in the last 10 years. 

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This is the first time I've seen the northern tip of the Antarctic Peninsula completely surrounded by solid ice; usually, the tip is exposed to the open ocean, even in the dead of winter, or there's fragmented low concentration ice between the Peninsula and Chile.

 

SSTs are also dropping rapidly to the east of the Antarctic Peninsula where some of the huge positive anomalies in sea ice are. There's a belt of generally below average SSTs around 60S, probably due to the impressive growth of the ice sheet with the -AAO coupled with the long-term cooling of the Southern Ocean which has been ongoing since the 1970s.

 

Overall very impressive to see signs of recovery on both sides of the cryosphere. We're probably looking at one of the best overall global sea ice anomalies in the last 10 years. 

 

You may want to rethink you last sentence.  According to CT [link], the global SIA anomaly is still negative, though it has been positive much of 2013 and several times over the past ten years.  So we aren't even looking at the best overall global sea ice anomalies for the past ten months, much less the past ten years.

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You may want to rethink you last sentence.  According to CT [link], the global SIA anomaly is still negative, though it has been positive much of 2013 and several times over the past ten years.  So we aren't even looking at the best overall global sea ice anomalies for the past ten months, much less the past ten years.

 

 

More than that.  The new ice down there is super thin.  The global volume change is still completely in the dumps.

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You may want to rethink you last sentence.  According to CT [link], the global SIA anomaly is still negative, though it has been positive much of 2013 and several times over the past ten years.  So we aren't even looking at the best overall global sea ice anomalies for the past ten months, much less the past ten years.

 

 

More than that.  The new ice down there is super thin.  The global volume change is still completely in the dumps.

Its new extent, that ice is never thick, but the fact it does exists and wasn't modeled to exist, says something. I know there are a few revisionist models that try to include the increase, but as a rule this wasn't supposed to happen.

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You may want to rethink you last sentence.  According to CT [link], the global SIA anomaly is still negative, though it has been positive much of 2013 and several times over the past ten years.  So we aren't even looking at the best overall global sea ice anomalies for the past ten months, much less the past ten years.

 

CT hasn't updated in 10 days either, during which there have been well above average extent increases (and presumably area) which would affect this. 

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CT hasn't updated in 10 days either, during which there have been well above average extent increases (and presumably area) which would affect this. 

 

You're right, CT hasn't updated in a while - but keep in mind that the Antarctic (this thread) is at the start of southern summer so it's beginning to melt about now which will offset some of the refreeze in the arctic.  I expect that the global SIA anomaly will remain negative, or close to neutral, when CT resumes updating.  Still no where near the best in ten years.

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Its new extent, that ice is never thick, but the fact it does exists and wasn't modeled to exist, says something. I know there are a few revisionist models that try to include the increase, but as a rule this wasn't supposed to happen.

 

The long-term decline in Antarctic sea ice was never supposed to be very strong. Which would make it much more susceptible to short-term variability and weather pattern changes which is exactly what we are seeing. 

 

On longer timescales, there is reasonable confidence that antarctic sea ice has seen a significant decline. 

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The long-term decline in Antarctic sea ice was never supposed to be very strong. Which would make it much more susceptible to short-term variability and weather pattern changes which is exactly what we are seeing. 

 

On longer timescales, there is reasonable confidence that antarctic sea ice has seen a significant decline. 

 

Really? Reconstructed or observed with satellites? 

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It wouldn't be able to have been observed by satellites, since we started measuring Sea Ice with satellites in the 1970s. 

 

That was my point, we are currently looking at the best extent since the satellite era began in Antarctica. Pre-Satellite data is cute, but not worth a whole lot in this discussion.

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Its new extent, that ice is never thick, but the fact it does exists and wasn't modeled to exist, says something. I know there are a few revisionist models that try to include the increase, but as a rule this wasn't supposed to happen.

 

 

It has nothing to do with it being new ice.

 

 

This thread is a sad little joke really.

 

The impact of an extra 1-2 million km2 of ice that is 30CM thick meaning it will have crappy albedo given how far South it is, how much water it will carry, how much energy it will trasnmit to the oceans below it's impact vs the Northern Hemisphere losing 2-3 million km2 of ice that was what 1000% thicker with tremendous albedo changes, local energy flux is no where near the same.

 

Because the SH ice is thin.  Around half of it or more is less than 1 meter thick at the end of the freeze season.

 

 

I would love to see something substansial come from this.

 

Wang didn't revise anything while predicting a SH Sea ice increase.  You offer nothing but false truths and lies.

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Wow, Friv, you sound pretty arrogant. What is the purpose of talking down to another poster like this? That shows a lack of class IMO. I'd expect more respect for others from you. Do you think you're perfect or something? I'm certainly not even close. Not throwing stones through glass houses is my recommendation.

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Wow, Friv, you sound pretty arrogant. What is the purpose of talking down to another poster like this? That shows a lack of class IMO. I'd expect more respect for others from you. Do you think you're perfect or something? I'm certainly not even close. Not throwing stones through glass houses is my recommendation.

 

Aren't you throwing stones, too?

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Aren't you throwing stones, too

 

 I'm criticizing Friv for not RESPECTFULLY disagreeing with another poster. Look at his last post. It was quite harsh and suggests extreme arrogance, which suggests feeling superior over another poster and being Mr. Perfect. Well, Friv is not anywhere close to being Mr. Perfect. I feel that I'm respectful when I disagree with another poster. So, I don't feel I'm being a hypocrite when criticizing Friv for being disrespectful. If I did, I'd be guilty of hypocrisy (what I'd consider throwing stones). What is wrong with robust but civil discussion/debate?

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