Antarctic ice

An article at the Live Science website says that we sceptics are putting far too much emphasis on the current high levels of Antarctic sea ice. The title is a bit of a straw man:

Record-High Antarctic Sea Ice Levels Don't Disprove Global Warming

I don't think anyone has actually said this - certainly the article doesn't give any examples, although it does stoop to putting words into Steven Goddard's mouth:

He reasons that the Southern Hemisphere must be balancing the warming of the Northern Hemisphere by becoming colder (and thus, net global warming is zero).

The Goddard article is here - so you can judge for yourself whether the bit is actually something Goddard said or not.

More interestingly, the article quotes Mark Serreze of NSIDC as follows:

Projections made from climate models all predict that global warming should impact Arctic sea ice first and most intensely, Serreze said. "We have known for many years that as the Earth started to warm up, the effects would be seen first in the Arctic and not the Antarctic. The physical geography of the two hemispheres is very different. Largely as a result of that, they behave very differently."

This is very interesting, because I was discussing this very issue with Ed Hawkins and Doug McNeall on Twittter last month. Ed pointed me to AR4 on the subject;

In 20th- and 21st-century simulations, antarctic sea ice cover is projected to decrease more slowly than in the Arctic (Figures 10.13c,d and 10.14), particularly in the vicinity of the Ross Sea where most models predict a local minimum in surface warming. This is commensurate with the region with the greatest reduction in ocean heat loss, which results from reduced vertical mixing in the ocean (Gregory, 2000).

This seems to support Serreze on "more intense in the Arctic" but not on "first in the Arctic". Ed also pointed me to this article, which is cited by AR4. It says this in its abstract:

The climate change projections over the 21st century reveal that the annual mean sea ice extent decreases at similar rates in both hemispheres...

Here's the relevant graph

Changes in Arctic and Antarctic annual mean sea ice extent (a) and volume (b) at the end of the 21st century. For each model the left (right) bar represents Arctic (Antarctic). The model FGOALS-g1.0 was excluded from the model average.The extent projections, which is what Live Science are discussing, doesn't seem to make the case.

Comments

[Dave Salt]

Heide De Klein: [snip] much of the arguments surrounding CAGW are based upon a lack of understanding of the Scientific Method (i.e. hypothesize, predict, test, compare, modify or enhance, predict, test... etc.) and the fact that it's mostly based upon predictions that have not been sufficiently tested or, even worse, falsified.

Concerning the original subject of this thread, my understanding is that a lack of coverage of the Antarctic maximum, as compared to the large coverage of the Arctic minimum, is direct proof of media bias but proves nothing about CAGW.

[Epimendes]

My understanding is that water is predominantly what melts arctic ice and not air because it has so little specific heat by volume.

Any of you have a link to this?

Obviously there is a tie up between warmer air and ocean but, I would imagine, only over hundreds or thousands of years. This whole business looks to me like a change of ocean currents and nothing to do with CO2, if the data is true.

[AlecM]

This report shows a remarkable fact: http://www.scoop.co.nz/stories/SC1209/S00050/antarctic-ice-area-sets-record-high.htm

“Over the 33-year period aggregate global sea ice volumes have remained steady.........

“The author also avoids mentioning the glaring facts that no significant global warming has been recorded in the past 16 years, and that sea level rise is apparently decelerating.'

Looks like game, set and match for sanity......

[Heide De Klein]

We've had plenty of direct proof of media bias. In fact we had exactly the same situation in 2007 when there were record highs/lows in the antarctic/arctic.

[ducdorleans]

re. Arctic and/or Antarctic (sea) ice extent ...

could somebody direct me to either

- a theory that states the exact surface that it should be, taking into account all known variables ?

- or a number, representing a direct line to the Maker, where I could check what number he had in mind when he created this thing called earth ?

tia

[Richard Betts]

HaroldW

The latest Met Office analysis of Arctic sea ice is here.

Cheers

Richard

[HaroldW]

Thanks very much for the link Richard.

I find it a little odd that a paper of August 2012 stated "Since 2007, while there have been years with near-record low ice cover [...], there has not been a new record set, despite an ongoing decline in multi-year ice." By mid-August it was quite apparent that the sea ice extent record would be broken. In fact the ice extent has been at or below 2007 levels all summer. [Source]

Looking at the paper's conclusions re: ice-free Arctic, I think the difference between the Met Office prediction of 2040 to 2060, and other predictions of 2015 to 2020, is an exaggeration. Figure 4.1.2 shows that the Met Office expects the September ice area to drop to around 1 million km^2 by c.2020, but only slowly decrease to zero over the next 30 to 40 years. Whether that last bit of ice succumbs immediately or a few decades later isn't a critical difference, although it seems to be the milestone most often mentioned. The key effects of minimal Arctic summertime ice will be present in any case by around 2020.

In any case, I'm pleased that the Met Office didn't go all "Chicken Little" over the Arctic ice reduction, in notable contrast to some commentators.

[Geoff Cruickshank]

Thankyou for that link Richard.
Using this site
http://climexp.knmi.nl/select.cgi?id...field=noaa_olr
and entering 70-90N, 0-360E, it appears that the OLR for the ocean area is up about an average of 4-6w / m2 since about 2006. I'm wondering would this most likely be due to
1) More open water in the melt season
2) Warmer water when there is open water
3) Change in cloud cover
or something else.
Appreciate any help with this.

[DennisA]

Dung says, (first comment):

As with all things said by both (or all?) sides in the Climate debate the mistake is as follows:

We have known for many years that as the Earth started to warm up, the effects would be seen first in the Arctic and not the Antarctic

Correct version :

We have believed for many years that as the Earth started to warm up, the effects would be seen first in the Arctic and not the Antarctic.
-------------------------------------------------------------------------------------

I posted this at WUWT, as they linked to the Bishop, I thought it appropriate to re-post it, with a little extra comment .

Why is Alaska cooling?

“The First Decade of the New Century: A Cooling Trend for Most of Alaska”,
G. Wendler*, L. Chen and B. Moore, Alaska Climate Research Center, Geophysical Institute, University of Alaska, Fairbanks, AK 99775, USA

http://www.benthamscience.com/open/toascj/articles/V006/111TOASCJ.pdf

Abstract:
“During the first decade of the 21st century most of Alaska experienced a cooling shift, modifying the long-term warming trend, which has been about twice the global change up to this time. All of Alaska cooled with the exception of Northern Regions.

This trend was caused by a change in sign of the Pacific Decadal Oscillation (PDO), which became dominantly negative, weakening the Aleutian Low. This weakening results in less relatively warm air being advected from the Northern Pacific. This transport is especially important in winter when the solar radiation is weak. It is during this period that the strongest cooling was observed.

In addition, the cooling was especially pronounced in Western Alaska, closest to the area of the center of the Aleutian Low. The changes seen in the reanalyzed data were confirmed from surface observations, both in the decrease of the North-South atmospheric pressure gradient, as well as the decrease in the mean wind speeds for stations located in the Bering Sea area.”

There is an interesting paper here on the PDO and ENSO, especially so in view of Bob Tisdale's recent work on ENSO: “Understanding Alaska’s Climate Variation”, John Papineau, Ph.D NWS Anchorage, Alaska, http://pafc.arh.noaa.gov/climvar/climate-paper.html

Tisdale link:http://wattsupwiththat.com/2012/09/16/tisdale-the-warming-of-the-global-oceans-are-manmade-greenhouse-gases-important-or-impotent/

Also some interesting temperature history from Sue Ann Bowling (rtd) here:
http://climate.gi.alaska.edu/Bowling/FANB.html

and this: “Problems with the Use of Climatological Data to Detect Climatic Change at High Latitudes” http://climate.gi.alaska.edu/Bowling/AKchange.html

The PDO shift in the mid 70′s was the reason for the jump in temperature in 1976-7 and effectively is the “polar amplification” where the Arctic has supposedly warmed at twice the rate of the rest of the planet. This description from 2005 seems to have been disappeared, but is still on Wayback, the charts are similar to Sue Ann Bowling’s.

http://web.archive.org/web/20051124061828/http://climate.gi.alaska.edu/ClimTrends/Change/4904Change.html

“If a linear trend is taken through mean annual temperatures, the average change over the last 5 decades is 3.4°F. However, when analyzing the trends for the four seasons, it can be seen that most of the change has occurred in winter and spring, with less of a change in summer and autumn”

“Considering just a linear trend can mask some important variability characteristics in the time series. Figure 2 shows clearly that this trend is non-linear: a linear trend might have been expected from the fairly steady observed increase of CO2 during this time period. The figure shows the temperature departure from the long-term mean (1949-2004) for the average of all stations.

It can be seen that there are large variations from year to year and the 5-year moving average demonstrates cyclical behavior. The period 1949 to 1975 was substantially colder than the period from 1977 to 2004, however since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations.

In 1976, a stepwise shift appears in the temperature data, which corresponds to a phase shift of the Pacific Decadal Oscillation from a negative phase to a positive phase.

Synoptic conditions with the positive phase tend to consist of increased southerly flow and warm air advection into Alaska during the winter, resulting in positive temperature anomalies.”

If you read the Papineau paper, you see that the PDO was also negative during the cooling of the 60's and 70's. The charts from Sue Ann Bowling are interesting because they show the phase shift in temperature just by removing one data point. Instead of a linear progression you get two distinct levels.

Around 2020 should be interesting when the next reversal should take place and "global warming" returns, thereby proving the models "correct".

Who was that guy with the razor?

[Sparks]

@Richard Betts The Arctic sea Ice extent went above normal or was at normal last winter, then NSIDC put a new trailing average algorithm online with no notice, and bungled the climatology in the process. There was a lot of controversy over this, but this is the norm in climate science and some people have no memory at all of these events in this field of science.

"seems to be a combination of reduced thickness over last winter, which led the ice to be more susceptible to being broken up when conditions became stormy in the summer."

How can extent be up but thickness be down?, If the storms in the summer reduced the sea Ice thickness and sea Ice extent over this summer wouldn't the majority of sea Ice that is left be the thickest ice and therefor shouldn't this Ice be thicker next year as a result with greater sea Ice extent if their are no major storms to speed up the seasonal melt. As far as I'm aware temperatures in the Arctic are still below the freezing point of water. If you look at the weak data the right way it seems the Arctic may have a surprise coming. :)

[Sparks]

The south pole (Antarctica) cools first it's land based! you can be a real idiot and say; Sea ice warms first.

[john williams]

Keep in mind it was also Mark Serreze that said the Bering Sea ice in 2010 was a "fluke". Not a word from Serreze about 2012 30 year record ice in the Bering Sea, nor Alaska which has been referred to as the canary in the coal mine.

They just make it up as they go along.