Poles apart: Arctic sea ice has shrunk but Antarctic sea ice has grown

Jul 09, 2014 by Dr Daryl Holland

A new study of satellite sea ice measurements shows that over the last 35 years there have been dramatic changes in sea ice cover around the world.

Lead investigator, Professor Ian Simmonds, from the School of Earth Sciences at the University of Melbourne said, "The late-summer Artic coverage has shrunk by 3 million square kilometres since 1979."

"There were significant decreases for every month of the year, with the greatest rate of decrease in September. Some are now suggesting that September sea ice could disappear from the Arctic in as little as 25 years.

"In contrast, Antarctic sea ice has been expanding, and 2013 was a record-breaking year. In September, we saw the greatest coverage of sea ice since satellite records started in 1979," said Professor Simmonds.

Overall, sea ice around the world is shrinking by about 35,000 square kilometres per year.

These dramatic changes are of concern as the polar regions influence global climate patterns.

Professor Simmonds said, "It seems counter-intuitive, but the growth in the Antarctic sea ice is consistent with global warming and the effects of increased . There is strong evidence to indicate changes in the concentration of greenhouse gases in the atmosphere are leading to region-specific changes in climate."

"The greenhouse effect is strengthening the westerlies over the Southern Ocean and this could be causing the increase in the Antarctic sea ice zone. Ultimately ocean warming will counteract this but it may be a number of years before that takes place."

This study is published online in the Annals of Glaciology.

Explore further: How wind helps Antarctic sea ice grow, even as the Arctic melts

More information: Annals of Glaciology, www.igsoc.org/annals/56/69/a69A909.html

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User comments : 34

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antigoracle
1.4 / 5 (20) Jul 09, 2014
Wow!!
Just when the "science" was settled, they add another chapter in their AGW Scientology doctrine.
runrig
4.5 / 5 (16) Jul 09, 2014
Wow!!
Just when the "science" was settled, they add another chapter in their AGW Scientology doctrine.

Just basic meteorology oh spamming denier.
Go tell your doctor he dont know nothin cos you red a blog wot said e wer rong.
FFS
The world does bend to your rules my friend.
To twist it around to say the ignorant know better than the expert is a bizarre psychology that the Internet age has grown... you strange types can Blog and bolster your own paranoia, with "just logical" "facts" like ... err - CO2 will sink (swallow) GW contradicts the 2nd law of thermodynamics (hockeyschtick.com).
Far, far beyond what Mr Dunning and Mr Kruger imagined.
Distilled through the selfish grey-matter of the right-winger. Who doesn't what "his" tax dollars touched.
Ah f***g diddums.
The Alchemist
3.6 / 5 (8) Jul 09, 2014
Hmmm... nothing about ice thickness or geometry.

I'll take a guess that ice build-up is thinner and thus less permanent in character. Lending itself to greater weather extremes, and other predictable effects we'll all be able to see from home.

If we are not so unbiased to observe.
Captain Stumpy
4.3 / 5 (11) Jul 09, 2014
Hmmm... nothing about ice thickness or geometry.
I'll take a guess that ice build-up is thinner and thus less permanent in character. Lending itself to greater weather extremes, and other predictable effects we'll all be able to see from home.
If we are not so unbiased to observe.
@Alkie AKA Verkle
Now is YOUR CHANCE to prove you are correct!
http://dialogueso...nge.html

go get your $30,000! it is waiting... but hurry... you dont have to be original, but you DO have to be first! someone else steals your idea's and proves it first, you will not get SQUAT!

better hurry to the challenge... PROVE IT
PROVE YOURSELF CORRECT

failure to do it only reinforces and proves to US and EVERYONE ELSE that you are only another 2-bit TROLL
Dr_toad
Jul 09, 2014
This comment has been removed by a moderator.
TegiriNenashi
1.5 / 5 (17) Jul 10, 2014
Lame excuses. Decreased salinity, and ozone hole were just laughable arguments. Increased winds is plausible, but is hard to verify/refute. Why not much simpler explanation (that southern polar region temperatures didn't really change, or actually dropped)?

Please note, that with total ice area (northern+southern hemisphere) running in the black -- just contrary to the very polar amplification effect -- where does it leave you with global warming hypothesis?
runrig
4.5 / 5 (15) Jul 10, 2014
Lame excuses. Decreased salinity, and ozone hole were just laughable arguments. Increased winds is plausible, but is hard to verify/refute. Why not much simpler explanation (that southern polar region temperatures didn't really change, or actually dropped)?

Only to the ignorant denier my friend.
Otherwise it's just simple meteorology and physics. Shame that innit?
Temps haven't dropped and sea ice isn't reliant on 0C or confined, as is the Arctic's - it is free to expand if blown.

Please note, that with total ice area (northern+southern hemisphere) running in the black -- just contrary to the very polar amplification effect -- where does it leave you with global warming hypothesis?

Sorry, as stated above, sea-ice isn't a proxy for temps. It's the freezing of water that can take place between -3C and OC... so you see, that is a very inaccurate thermometer.
Also, sea-ice extent with both poles added is still declining ,,,, AND Antarctic ice is on average half as thick
ryggesogn2
1.3 / 5 (13) Jul 10, 2014
What about land ice?
Antarctica is a continent.
runrig
4.4 / 5 (14) Jul 10, 2014
What about land ice?
Antarctica is a continent.

Very probably increasing in parts my friend ..... because you see WARMER air will hold more snow .... as it must be at an average height of 12000ft.
Western ice sheets are slowly melting, as you would know if you did not reflexively ignore/deny science published on here.
Back to la-la land you go.
TegiriNenashi
1.5 / 5 (15) Jul 10, 2014
Sorry, as stated above, sea-ice isn't a proxy for temps. It's the freezing of water that can take place between -3C and OC... so you see, that is a very inaccurate thermometer


Are you for real? Take a look at basic sea water freezing point calculator
http://www.csgnet...alc.html
Consider two extreme salinity levels: 30 and 35 PSU (very generous threshold; you can see from any salinity map that PSU variation in polar regions is much lower). One corresponds to temp -1.5C and another -2.0C. Both "-3C" and "0C" featured in your hogwash are pure nonsense. Given that regional yearly average temperature swings are typically several degrees, that 0.5K error band makes ice cover pretty good temperature proxy.

BTW, how is that infamous 2007 prediction that Arctic sea ice would be gone in 5 years is doing lately?
ryggesogn2
1.3 / 5 (12) Jul 10, 2014
If land ice is increasing, more heat is being lost.
antigoracle
1.6 / 5 (14) Jul 10, 2014
Western ice sheets are slowly melting, as you would know if you did not reflexively ignore/deny science published on here.
--runrig
As you would well know, this is due to geothermal activity, if you did not try to use this to propagate your CO2 lies.
runrig
4.4 / 5 (13) Jul 11, 2014
Western ice sheets are slowly melting, as you would know if you did not reflexively ignore/deny science published on here.
--runrig
As you would well know, this is due to geothermal activity, if you did not try to use this to propagate your CO2 lies.

There is a contribution, yes but you don't get to claim it all my friend ... except in your dreams anyway.
And it's just the Thwaites Glacier .... A massive slice of the continent (not).
cdn.antarcticglaciers.org/wp-content/uploads/2012/10/Pine_island_glacier.png

http://phys.org/n...mal.html
runrig
4.4 / 5 (14) Jul 11, 2014
If land ice is increasing, more heat is being lost.


Look ryggy....
I did tell you to leave the science alone for the big boys.

When water freezes it gives up heat (latent) and adds to the temperature of the surrounding air.
It is not being lost.
It is being stored as a buffer and solar energy will eventually be used to melt it.
.... the same (amount of) solar energy that was given up as latent heat when it froze.
runrig
4.3 / 5 (12) Jul 11, 2014
Are you for real? ....
Consider two extreme salinity levels: 30 and 35 PSU (very generous threshold; you can see from any salinity map that PSU variation in polar regions is much lower). One corresponds to temp -1.5C and another -2.0C. Both "-3C" and "0C" featured in your hogwash are pure nonsense. Given that regional yearly average temperature swings are typically several degrees, that 0.5K error band makes ice cover pretty good temperature proxy.

OK - I used a figure (-3C) I had in my head from years ago. It is around -1.8C normally. (35psu).
Hogwash?? You dont agree that fresh water freezes at 0C then?
We are talking of freshening here as land ice melts but you are right in the sense that the range in practise is a lot narrower than I stated.
BTW, how is that infamous 2007 prediction that Arctic sea ice would be gone in 5 years is doing lately?

You mean the one that was made by one team and did not come from the IPCC
http://news.bbc.c...9797.stm
TegiriNenashi
1.7 / 5 (12) Jul 11, 2014
You dont agree that fresh water freezes at 0C then?
We are talking of freshening here as land ice melts but you are right in the sense that the range in practise is a lot narrower than I stated.


Look at the sea ice map. Check the distance between floating ice boundary and the continent. It is 1000 km or more. You imply that the alleged melting of ice shelves 1000 km away makes the seawater at the floating ice boundary fresh??? Or there are so many icebergs floating that the entire Southern ocean is freshwater? Shall we go through simple calculation comparing icebergs volume to the ocean? Even simpler argument: look at salinity map, and tell us where you see 0 PSU.

The salinity argument is dead. The "increased winds" may linger for a while, but will be dispelled too. It is hard to argue with ubiquitous Law of Nature: "lower temperature -> more ice".
runrig
4.4 / 5 (13) Jul 11, 2014
Look at the sea ice map. Check the distance between floating ice boundary and the continent. It is 1000 km or more. You imply that the alleged melting of ice shelves 1000 km away makes the seawater at the floating ice boundary fresh??? Or there are so many icebergs floating that the entire Southern ocean is freshwater? Shall we go through simple calculation comparing icebergs volume to the ocean? Even simpler argument: look at salinity map, and tell us where you see 0 PSU.

The salinity argument is dead. The "increased winds" may linger for a while, but will be dispelled too. It is hard to argue with ubiquitous Law of Nature: "lower temperature -> more ice".

No the ice forms closer the continent (sooner) because of lower salinity and is blown further afield because of increased winds (which are less convergent into the continent as a result)
So you are saying that ice is increasing there because it's colder? - while the Arctic is decreasing because?
I would welcome your evidence
TegiriNenashi
1.9 / 5 (13) Jul 11, 2014
I can't deny that ice can form close to the continent as well. However, in southern winter season, when ice cover is growing, it is reasonable to suggest that the temperature close to the continent is well below freezing (regardless of the exact figure we arguing about). It is hard to imagine any glassier melt happening this time of year.

Regardless of the fine points, my main problem with warmist interpretation is that they take well observed phenomenon (increased sea ice) and try to explain it in terms of something not that well measured (increased wind). Sure this is plausible, but is it compelling argument?
TegiriNenashi
1.6 / 5 (13) Jul 11, 2014
Regarding Arctic, the simplest possible explanation is that satellite observation record started in 1979, just around infamous "ice age" news buzz. This anomalous reference point created illusion of diminishing ice cover.

You may be tempted to exclaim: "Just look at the graph, how can you be blind to a trend here!", to which my answer is: "I would believe to what this graph implies when I see the same story in southern hemisphere".
Captain Stumpy
4.1 / 5 (13) Jul 12, 2014
where does it leave you with global warming hypothesis?
@TegiriNenashi
Well, why don't you just explain it all at this link?
http://dialogueso...nge.html

PROVE to everyone that AGW is not happening, and that the science is wrong.
you win, you get $30,000.00
fame, and bragging rights
AND likely everyone here will respect the opinion too, because SCIENCE is about empirical data, so....
USE the scientific method and prove AGW wrong at tahat link.
show us all up...
The salinity argument is dead. The "increased winds" may linger for a while, but will be dispelled too. It is hard to argue with ubiquitous Law of Nature
well SHOW IT TO THE SITE and prove that we are all ignorant and that a predominant amount of the WORLD scientists are wrong!

what say you? CAN you offer up something that will be accepted?
or are you afraid of public humiliation?
runrig
4.1 / 5 (14) Jul 12, 2014
I can't deny that ice can form close to the continent as well. However, in southern winter season, when ice cover is growing, it is reasonable to suggest that the temperature close to the continent is well below freezing (regardless of the exact figure we arguing about). It is hard to imagine any glassier melt happening this time of year.

tegri:
Primary melt is occurring on the bottom of the ice-shelf, via contact with warmer waters. This will happen all year round, given currents bring in that warmer water.
also...
". Such studies typically assume negligible melting in water near the freez-
ing point on the Antarctic continental shelf. Where grounding lines are deep, however, melt
rates can exceed 20 m/year in water at -2C, close to the ambient temperature for most of
our study areas."
http://trs-new.jp...n_detail
TegiriNenashi
1.6 / 5 (14) Jul 12, 2014
Assume that glacier internals temperature is the same as ambient air. That would be -20C this time of year, at least. According to your article the alleged deep ocean current temperature is merely 2-3K above melting point. Given not much difference between thermal capacities of ice and water (compared to an order of magnitude temperature difference) how much of current water needs to be in contact with ice in order to heat it from -20C to melt point? If you need tons and tons of sea water exchanging the heat and resulting in melting of just a cubic meter of ice, don't you think this newly melted fresh water would be diluted to the point that difference in salinity would be negligible?
Eddy Courant
1.7 / 5 (10) Jul 13, 2014
Oh we're DOOMED
Egleton
4.6 / 5 (11) Jul 14, 2014
The oceans are storing most of the heat. The atmosphere is a puny thin thing.
The extra heat of the oceans upwells underneath the snouts of the glaciers causing the grounding line to migrate inland. More land ice finds itself floating.
Nice video from NASA
https://www.youtu...YHMx5bN8
TegiriNenashi
1.5 / 5 (8) Jul 14, 2014
Why this "extra heat of the oceans" does't cause sea ice cover shrinking, but still is malicious enough to travel under 1000 km of expanding sea ice and undermine WAIS? Does ARGO float network support your hypothesis?
Maggnus
4.1 / 5 (9) Jul 14, 2014
Why this "extra heat of the oceans" does't cause sea ice cover shrinking, but still is malicious enough to travel under 1000 km of expanding sea ice and undermine WAIS? Does ARGO float network support your hypothesis?
Why pretend interest? It'sd been explained to you multiple times by a number of different people. Just admit you are too blinded by ideology to understand science and get lost.
Egleton
5 / 5 (8) Jul 14, 2014
Does ARGO float network support your hypothesis?

Not a hypothesis- it is an empirical observation.
TegiriNenashi
1.6 / 5 (7) Jul 14, 2014
Does ARGO float network support your hypothesis?

Not a hypothesis- it is an empirical observation.


https://climateda...sed-argo

That looks like plateau to me. Keep inventing excuses.
thermodynamics
5 / 5 (7) Jul 14, 2014
Tegiri said:
Does ARGO float network support your hypothesis?

Not a hypothesis- it is an empirical observation.


https://climateda...sed-argo

If you go to the section on "expert guidance" in the same URL you will find that they have an analysis of the data:

"The 6-year trend is calculated using a weighted least square fit and accounts for 0.54±0.1 Wm-2 for the ocean surface, i.e. 0.38±0.1 Wm-2 for the Earth's surface."

Are you saying your eye is better than their regression analysis or are you just saying you didn't read it?

TegiriNenashi
1.6 / 5 (7) Jul 14, 2014
"Are you saying your eye is better than their regression analysis or are you just saying you didn't read it?"

It is flat compared to the ocean's heat content graph they exhibit prior to Argo. If one believes their error margin (20-25%) then what kind of error was it when they had two or three order of magnitude less number of sensors?
thermodynamics
5 / 5 (7) Jul 14, 2014
Tegiri says:
"Are you saying your eye is better than their regression analysis or are you just saying you didn't read it?"

It is flat compared to the ocean's heat content graph they exhibit prior to Argo. If one believes their error margin (20-25%) then what kind of error was it when they had two or three order of magnitude less number of sensors?


Did you read the information? They readily admit that there are uncertainties. However, they also show the trend and error in the trend.

Once again, is your eye better than the regression analysis they did? Is that your claim?
TegiriNenashi
1 / 5 (6) Jul 14, 2014
If you insist: by simple eyeballing this graph, one can easily see that the sky is not falling. Whether, this intuition is better or not compared to their "rigorous" (or should I say "robust"?) regression analysis is irrelevant.
Captain Stumpy
5 / 5 (7) Jul 14, 2014
If you insist: by simple eyeballing this graph, one can easily see that the sky is not falling
@Thermo
there is your answer... he simply eyeballed the graph... he can't read, apparently
Whether, this intuition is better or not compared to their "rigorous" (or should I say "robust"?) regression analysis is irrelevant.
and this proves he knows SQUAT about science, statistics etc...

too bad... no win at the challenge for you, teg
Egleton
5 / 5 (5) Jul 14, 2014
empirical
ɛmˈpɪrɪk(ə)l,ɪm-/
adjective
adjective: empirical

based on, concerned with, or verifiable by observation or experience rather than theory or pure logic.
"they provided considerable empirical evidence to support their argument"
synonyms: observed, seen, factual, actual, real, verifiable, first-hand;
experimental, experiential;
practical, pragmatic, hands-on, applied;
technicalheuristic;
rareempiric
"many of these predictions have received empirical confirmation"
antigoracle
1 / 5 (4) Jul 15, 2014

https://climateda...sed-argo

That looks like plateau to me. Keep inventing excuses.

Nice one.
They say it takes 20 lies to coverup a single one.
Well, the AGW Chicken Littles can't count pass 20 without dropping their pants. One can expect more lies and excuses from them.