Antarctic Ice Discussion

[Yozzer]

Has anyone noticed the anomolous area of ice just to the south-east of the Kerguelen Islands at approx 53S 70E? Any evidence as to what it is, i.e. a large berg or an area of thin surface ice? Also there seems to be a much smaller area approx 52S 5W, same question!

http://www.wetterzentrale.de/topkarten/fsdivka.html

 

(Click on Sudhemisphare!!)

Edited August 5, 2013 by Yozzer

[BornFromTheVoid]

Antarctic sea ice area booming again, but just behind 2010

http://arctic.atmos.uiuc.edu/cryosphere/

 

Sea ice extent, slightly above average

Edited August 15, 2013 by BornFromTheVoid

[loafer]

Antarctic sea ice area booming again, but just behind last year

http://arctic.atmos.uiuc.edu/cryosphere/

 

Sea ice extent, slightly above average

 

Antarctic Sea Ice Area is well above last year, it is just below 2010 (the record year). http://arctic.atmos.uiuc.edu/cryosphere/antarctic.sea.ice.interactive.html

 

Antarctic Sea Ice Extent anomaly is also second only to 2010. http://nsidc.org/data/seaice_index/index.html

[BornFromTheVoid]

Antarctic Sea Ice Area is well above last year, it is just below 2010 (the record year). http://arctic.atmos.uiuc.edu/cryosphere/antarctic.sea.ice.interactive.html

 

Antarctic Sea Ice Extent anomaly is also second only to 2010. http://nsidc.org/data/seaice_index/index.html

 

Ah yes, 2010, not last year

 

I presume you're referring to the monthly extent there?

[loafer]

Ah yes, 2010, not last year

 

I presume you're referring to the monthly extent there?

 

Yes, that's right.

[BornFromTheVoid]

Yes, that's right.

 

It's a pity that the NSIDC don't do an Antarctic version of this graph.

 

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

[Gray-Wolf]

I wonder why folk look at winter ice as some kind of measure and don't focus more on ice shelf loss/mass loss from the ice sheets?

 

Where we to see, in Antarctica, winter ice becoming multiyear ice then I could grasp it but to  see so many folk  spending such energies on something that is gone by Feb confuses me?

 

We see similar with Winter snowfall in the N.Hemisphere with similar, if not the same folk?, holding up record high snow cover over winter as significant when recent history shows us that it will all go long before any climatic impacts could be harvested from it? What is the point?

 

For me the increases in Weddell ice cover ( nobody focuses on the areas with less sea ice than their historic norm???) points to the impacts we have wrought from both the ozone hole and background AGW...neither anything to make a song and dance about?

 

We see ocean warmth circumnavigating the strengthened circumpolar current and thinning/collapsing ice shelfs so we know general warming is now getting through so how long before atmospheric warming encroaches further than the peninsula and we start seeing rapid changes ( akin to those occurring on Greenland) across the coastal regions of Antarctica? Surely this is an area more worthy of time spent by folks?

[thetonynator]

I wonder why folk look at winter ice as some kind of measure and don't focus more on ice shelf loss/mass loss from the ice sheets?

Presumably because it fits an agenda! 

Where we to see, in Antarctica, winter ice becoming multiyear ice then I could grasp it but to  see so many folk  spending such energies on something that is gone by Feb confuses me? We see similar with Winter snowfall in the N.Hemisphere with similar, if not the same folk?, holding up record high snow cover over winter as significant when recent history shows us that it will all go long before any climatic impacts could be harvested from it? What is the point? For me the increases in Weddell ice cover ( nobody focuses on the areas with less sea ice than their historic norm???) points to the impacts we have wrought from both the ozone hole and background AGW...neither anything to make a song and dance about? We see ocean warmth circumnavigating the strengthened circumpolar current and thinning/collapsing ice shelfs so we know general warming is now getting through so how long before atmospheric warming encroaches further than the peninsula and we start seeing rapid changes ( akin to those occurring on Greenland) across the coastal regions of Antarctica? Surely this is an area more worthy of time spent by folks?

To be fair with regard to summer ice in the SH, last summer had the second highest minimum on record so presumably it does make some difference with albedo and more multiyear ice, but not much.

[knocker]

Life in Antarctica Relies on Shrinking Supply of Krill

 

These tiny crustaceans are a bellwether of climate change.

 

http://news.nationalgeographic.com/news/2013/08/130817-antarctica-krill-whales-ecology-climate-science/

Edited August 20, 2013 by knocker

[stewfox]

It's a pity that the NSIDC don't do an Antarctic version of this graph.

 

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

 

 

I find the NSIDC very good at getting back to general questions so I raised the above query.

 

Feed back as follows

 

 

---------------------------

We don't currently have a "Chantarctic" tool, but will pass this suggestion along to the team involved.

 

Best regards,

Sarah

Sarah Tressel

NSIDC User Services

-------------------------------

[stewfox]

August 24 (Day 236) saw the 29th Daily Record of the Year for Antarctic Sea Ice Extent. This was the 6th record in a row.

 

http://sunshinehours.wordpress.com/tag/antarctic-sea-ice/

 

 

I cant see how we can support a wind argument ?

 

http://nsidc.org/data/seaice_index/images/daily_images/S_bm_extent_hires.png

Edited August 25, 2013 by stewfox

[knocker]

Can anyone explain to me why this fixation with the Antarctic sea ice gain is more important that arctic sea ice loss, smb loss in Greenland, loss from the Antarctic ice sheet and general loss from glaciers world wide? Coupled with sea level rises and natures indications of a warming climate.

[stewfox]

Can anyone explain to me why this fixation with the Antarctic sea ice gain is more important that arctic sea ice loss, smb loss in Greenland, loss from the Antarctic ice sheet and general loss from glaciers world wide? Coupled with sea level rises and natures indications of a warming climate.

 

So the southern hemisphere sea ice doesn't count but the northern hemisphere sea ice does ?. That's a new take on global.

 

Your global assumption are false anyway but can be picked up in other threads.

[knocker]

So the southern hemisphere sea ice doesn't count but the northern hemisphere sea ice does ?. That's a new take on global.

 

Your global assumption are false anyway but can be picked up in other threads.

I didn't say that but it's a matter of relative importance.

 

A major difference between the Arctic and Antarctic is the amount of multi-year sea ice (sea ice that has survived one summer) that is present. In the Antarctic most sea ice melts by the late summer, with only small amounts of ice persisting into the following winter along the coast of East Antarctic and over the western Weddell Sea. In the Arctic, however, there is a higher proportion of multi-year ice present.

 

During periods when solar radiation is received, a number of different 'polar feedback mechanisms can come into play, which can amplify small environmental changes. For example, in the case where the ocean is partially covered by sea ice, once the fractional ice cover has dropped to a certain level, enough solar radiation may be received to warm the upper layers of the ocean, resulting in the rapid melting of the remaining sea ice in a region. This is often the case along the coast of Dronning Maud Land, on the eastern side of the Weddell Sea, Antarctica, where there can be a rapid expansion of the coastal polynya (the ice-free region next to the coast) during December. A similar positive feedback is found over snow-covered land areas during the high latitude spring, where the snow can rapidly retreat once enough bare ground is exposed and sufficient heat has been absorbed by the surface. This takes place across northern Eurasia and results in extensive river runoff into the Arctic Ocean. 

Edited August 26, 2013 by knocker

[4wd]

Wrong kind of ice then as does not meet with theoretical projections.aka: disregard real world data when it does not suitIt's still ice, and will be glaring white regardless of all the other huff and puffGlobal sea ice is at or near normal.Arctic sea ice has rebounded remarkably.Declining ice caused by CO2 - unproven hypothesis.

[knocker]

That wasn't the question. It was what is the importance of increasing sea ice in some areas in winter in the Antarctic compared to the loss going on in the Arctic and other factors?

 

And I have no recollection of mentioning CO²

^.

[knocker]

From a paper by H. Jay Zwall, et al,  in 2002.

 

Variability of Antarctic sea ice 1979–1998

[1] The principal characteristics of the variability of Antarctic sea ice cover as previously described from satellite passive microwave observations are also evident in a systematically calibrated and analyzed data set for 20.2 years (1979–1998). The total Antarctic sea ice extent (concentration >15%) increased by 11,180 ± 4190 km² yr^−1 (0.98 ± 0.37% (decade)^−1). The increase in the area of sea ice within the extent boundary is similar (10,860 ± 3720 km² yr^−1 and 1.26 ± 0.43% (decade)^−1). Regionally, the trends in extent are positive in the Weddel Sea (1.4 ± 0.9% (decade)^−1), Pacific Ocean (2.0 ± 1.4% (decade)^−1), and Ross (6.7 ± 1.1% (decade)^−1) sectors, slightly negative in the Indian Ocean (−1.0 ± 1.0% (decade)^−1), and strongly negative in the Bellingshausen-Amundsen Seas sector (−9.7 ± 1.5% (decade)^−1)). For the entire ice pack, ice increases occur in all seasons, with the largest increase during fall. On a regional basis the trends differ season to season. During summer and fall the trends are positive or near zero in all sectors except the Bellingshausen-Amundsen Seas sector. During winter and spring the trends are negative or near zero in all sectors except the Ross Sea, which has positive trends in all seasons. Components of interannual variability with periods of about 3–5 years are regionally large but tend to counterbalance each other in the total ice pack. The interannual variability of the annual mean sea ice extent is only 1.6% overall, compared to 6–9% in each of five regional sectors. Analysis of the relation between regional sea ice extents and spatially averaged surface temperatures over the ice pack gives an overall sensitivity between winter ice cover and temperature of −0.7% change in sea ice extent per degree Kelvin. For summer some regional ice extents vary positively with temperature, and others vary negatively. The observed increase in Antarctic sea ice cover is counter to the observed decreases in the Arctic. It is also qualitatively consistent with the counterintuitive prediction of a global atmospheric-ocean model of increasing sea ice around Antarctica with climate warming due to the stabilizing effects of increased snowfall on the Southern Ocean.

 

 

http://lgmacweb.env.uea.ac.uk/ajw/Sea_ice/zwally_et_al_2002.pdf

[BARRY]

but that was 11 years ago

[knocker]

I know but it was referenced in fine book, Climate Change in the Polar Regions, Turner and Marshall,2011 so the basic argument still applies. There have been other more recent papers posted on here which introduce later thinking on the subject but I don't see the point of going over it all again.

[stewfox]

I know but it was referenced in fine book, Climate Change in the Polar Regions, Turner and Marshall,2011 so the basic argument still applies. There have been other more recent papers posted on here which introduce later thinking on the subject but I don't see the point of going over it all again.

 

In need what is the point as my original post was a update on Antarctica ice on a Antarctica ice thread and your comment was essentially what's the point.

 

At present global sea ice is just around average and positive/negative feedback mechanism at both poles are well documented and effect of ice/sea/solar radiation angle of etc etc again are well documented and have all been published in the last few years.

[Cheshire Freeze]

Hang on one moment....just seen this thread.

 

So we have lessening sea ice in the Arctic and increasing sea ice in the Antarctic? Makes me wonder what all the fuss is about then as there is obviously some balancing going on when we take the earth as a whole? Surely if CO2 was as big of an issue as some are making out, we'd be seeing a similar rate of decrease towards the S pole as we are at the N pole. Or does this warming effect/melt out just discriminate willy nilly.

[stewfox]

Hang on one moment....just seen this thread.

 

So we have lessening sea ice in the Arctic and increasing sea ice in the Antarctic? Makes me wonder what all the fuss is about then as there is obviously some balancing going on when we take the earth as a whole? Surely if CO2 was as big of an issue as some are making out, we'd be seeing a similar rate of decrease towards the S pole as we are at the N pole. Or does this warming effect/melt out just discriminate willy nilly.

 

in need

 

http://wattsupwiththat.com/2013/07/22/why-antarctic-sea-ice-is-the-better-climate-change-indicator/

 

There are a number of theories why the Antarctic ice continues to expand many plausible, cant see from the attached photo that the wind theory holds out unless someone is standing in the middle and blowing out in all directions ?

 

http://nsidc.org/data/seaice_index/images/daily_images/S_bm_extent_hires.png

[knocker]

There are a number of theories why the Antarctic ice continues to expand many plausible, cant see from the attached photo that the wind theory holds out unless someone is standing in the middle and blowing out in all directions ?

 

http://nsidc.org/data/seaice_index/images/daily_images/S_bm_extent_hires.png

 

Why Antarctic sea ice cover has increased under the effects of climate change

 

The first direct evidence that marked changes to Antarctic sea ice drift have occurred over the last 20 years, in response to changing winds, is published this week in the journal Nature Geoscience. Scientists from NERC's British Antarctic Survey (BAS) and NASA's Jet Propulsion Laboratory (JPL), Pasadena California explain why, unlike the dramatic losses reported in the Arctic, the Antarctic sea ice cover has increased under the effects of climate change.

 

Maps created by JPL using over 5 million individual daily ice motion measurements captured over a period of 19 years by four US Defense Meteorological satellites show, for the first time, the long-term changes in sea ice drift around Antarctica.

 

Lead author, Dr Paul Holland of BAS says: "Until now these changes in ice drift were only speculated upon, using computer models of Antarctic winds. This study of direct satellite observations shows the complexity of climate change. The total Antarctic sea-ice cover is increasing slowly, but individual regions are actually experiencing much larger gains and losses that are almost offsetting each other overall. We now know that these regional changes are caused by changes in the winds, which in turn affect the ice cover through changes in both ice drift and air temperature. The changes in ice drift also suggest large changes in the ocean surrounding Antarctica, which is very sensitive to the cold and salty water produced by sea-ice growth."

 

"Sea ice is constantly on the move; around Antarctica the ice is blown away from the continent by strong northward winds. Since 1992 this ice drift has changed. In some areas the export of ice away from Antarctica has doubled, while in others it has decreased significantly."

 

Sea ice plays a key role in the global environment – reflecting heat from the sun and providing a habitat for marine life. At both poles sea ice cover is at its minimum during late summer. However, during the winter freeze in Antarctica this ice cover expands to an area roughly twice the size of Europe. Ranging in thickness from less than a metre to several metres, the ice insulates the warm ocean from the frigid atmosphere above.

 

The new research also helps explain why observed changes in the amount of sea-ice cover are so different in the two Polar Regions. The Arctic has experienced dramatic ice losses in recent decades while the overall ice extent in the Antarctic has increased slightly. However, this small Antarctic increase is actually the result of much larger regional increases and decreases, which are now shown to be caused by wind-driven changes. In places, increased northward winds have caused the sea-ice cover to expand outwards from Antarctica. The Arctic Ocean is surrounded by land, so changed winds cannot cause Arctic ice to expand in the same way.

 

Dr Ron Kwok, JPL says, "The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the winds around the continent."

 

There has been contrasting climate change observed across the Antarctic in recent decades. The Antarctic Peninsula has warmed as much as anywhere in the Southern Hemisphere, while East Antarctica has shown little change or even a small cooling around the coast. The new research improves understanding of present and future climate change. It is important to distinguish between the Antarctic Ice Sheet – glacial ice – which is losing volume, and Antarctic sea ice – frozen seawater – which is expanding.

###

This research was funded by the Natural Environment Research Council (NERC) and National Aeronautics and Space Administration (NASA).

The paper 'Wind-driven trends in Antarctic sea ice motion' by Paul R. Holland of British Antarctic Survey and Ron Kwok of the Jet Propulsion Laboratory, California, USA is published in Nature Geoscience this week.

I

issued by British Antarctic Survey

 

http://www.eurekalert.org/pub_releases/2012-11/bas-was110912.php

Edited August 26, 2013 by knocker

[stewfox]

Why Antarctic sea ice cover has increased under the effects of climate change

 

The first direct evidence that marked changes to Antarctic sea ice drift have occurred over the last 20 years, in response to changing winds, is published this week in the journal Nature Geoscience. Scientists from NERC's British Antarctic Survey (BAS) and NASA's Jet Propulsion Laboratory (JPL), Pasadena California explain why, unlike the dramatic losses reported in the Arctic, the Antarctic sea ice cover has increased under the effects of climate change.

 

Maps created by JPL using over 5 million individual daily ice motion measurements captured over a period of 19 years by four US Defense Meteorological satellites show, for the first time, the long-term changes in sea ice drift around Antarctica.

 

Lead author, Dr Paul Holland of BAS says: "Until now these changes in ice drift were only speculated upon, using computer models of Antarctic winds. This study of direct satellite observations shows the complexity of climate change. The total Antarctic sea-ice cover is increasing slowly, but individual regions are actually experiencing much larger gains and losses that are almost offsetting each other overall. We now know that these regional changes are caused by changes in the winds, which in turn affect the ice cover through changes in both ice drift and air temperature. The changes in ice drift also suggest large changes in the ocean surrounding Antarctica, which is very sensitive to the cold and salty water produced by sea-ice growth."

 

"Sea ice is constantly on the move; around Antarctica the ice is blown away from the continent by strong northward winds. Since 1992 this ice drift has changed. In some areas the export of ice away from Antarctica has doubled, while in others it has decreased significantly."

 

Sea ice plays a key role in the global environment – reflecting heat from the sun and providing a habitat for marine life. At both poles sea ice cover is at its minimum during late summer. However, during the winter freeze in Antarctica this ice cover expands to an area roughly twice the size of Europe. Ranging in thickness from less than a metre to several metres, the ice insulates the warm ocean from the frigid atmosphere above.

 

The new research also helps explain why observed changes in the amount of sea-ice cover are so different in the two Polar Regions. The Arctic has experienced dramatic ice losses in recent decades while the overall ice extent in the Antarctic has increased slightly. However, this small Antarctic increase is actually the result of much larger regional increases and decreases, which are now shown to be caused by wind-driven changes. In places, increased northward winds have caused the sea-ice cover to expand outwards from Antarctica. The Arctic Ocean is surrounded by land, so changed winds cannot cause Arctic ice to expand in the same way.

 

Dr Ron Kwok, JPL says, "The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the winds around the continent."

 

There has been contrasting climate change observed across the Antarctic in recent decades. The Antarctic Peninsula has warmed as much as anywhere in the Southern Hemisphere, while East Antarctica has shown little change or even a small cooling around the coast. The new research improves understanding of present and future climate change. It is important to distinguish between the Antarctic Ice Sheet – glacial ice – which is losing volume, and Antarctic sea ice – frozen seawater – which is expanding.

###

This research was funded by the Natural Environment Research Council (NERC) and National Aeronautics and Space Administration (NASA).

The paper 'Wind-driven trends in Antarctic sea ice motion' by Paul R. Holland of British Antarctic Survey and Ron Kwok of the Jet Propulsion Laboratory, California, USA is published in Nature Geoscience this week.

I

issued by British Antarctic Survey

 

http://www.eurekalert.org/pub_releases/2012-11/bas-was110912.php

 

Good theory (written at the end of 2012)  lets look at the evidence

 

Looked plausible in June 2013 (clear evidence of wind driven ice with some areas well up on average some well down)

 

http://notalotofpeopleknowthat.wordpress.com/2013/07/04/antarctic-sea-ice-well-above-normal-in-june/

 

 but if you looked at the attached how plausible is that explanation now in August ?

 

http://nsidc.org/data/seaice_index/images/daily_images/S_bm_extent_hires.png

 

There quote

-----------------------

""""Sea ice is constantly on the move; around Antarctica the ice is blown away from the continent by strong northward winds. Since 1992 this ice drift has changed. In some areas the export of ice away from Antarctica has doubled, while in others it has decreased significantly."

-----------------------

 

 

In August 2013 is there any area that shows a significant decrease ??

 

In fact by season end all areas maybe above the long terms average.

Edited August 26, 2013 by stewfox

[knocker]

Isn't this the important point?

 

It is important to distinguish between the Antarctic Ice Sheet – glacial ice – which is losing volume, and Antarctic sea ice – frozen seawater – which is expanding.