“Steepest slope ever.”
By Steven Goddard
We have been hearing a lot about how the decline in Arctic ice is following the “steepest slope ever.” The point is largely meaningless, but we can have some fun with it. The Bremen Arctic/Antarctic maps are superimposed above, showing that ice in the Antarctic is at a record high and growing at the “steepest slope ever.” You will also note that most of the world’s sea ice is located in the Antarctic. But those are inconvenient truths when trying to frighten people into believing that “the polar ice caps are melting.”
There are several favorite lines of defense when trying to rationalize away the record Antarctic ice.
1. It is the Ozone Hole – which is also the fault of evil, American SUV drivers. That is a nice guilt trip, but sadly the Ozone Hole doesn’t form until August and is gone by December. Strike one.
The next one is to point out that some regions of the west side of the tiny Antarctic Peninsula have been warming. Never mind that the Antarctic Peninsula is an active volcanic ridge, and that the waters around it have not shown any significant warming. Strike two.
UAH shows Antarctica cooling slightly over the last 30 years.
The third favorite line of defense is to argue that “we expected Antarctica to warm more slowly because of the mass of the southern oceans.” Nice try – “slower warming” is not the same as “cooling.” Strike three.
(The AGW view of Antarctica is every bit as irrational as FIFA’s stand that not having instant replays somehow helps the referees’ reputations.)
On to the Arctic. First graph is a JAXA comparison of 2006, 2007 and 2010. Note that 2006 and 2007 were nearly identical, until early July. The main difference between 2006 (second highest in the JAXA record) and 2007 (lowest in the JAXA record) was that strong southerly winds compacted and melted the ice in 2007. As you can see below, the summer extent numbers are nearly meaningless before July/August. So far, 2010 is tracking very closely with both 2006 and 2007, and it appears the three will intersect in about a week.
Let’s take a closer look at the mechanisms using the PIPS ice and wind data. If we watch the movement of Arctic ice during the summer, we can see that when the winds blow away from the pole (i.e. from the north) the ice expands. When the wind blows from the south, the ice contracts. Some summers, the winds alternate between north and south, and the ice extent changes less during the summer – like in 2000 below.
Other years, like 2007, the summer winds blew consistently from the south, causing the ice to melt at a faster pace and compress towards the north.
So basically, it is weather (wind) rather than climate which controls the summer minimum. Of course, it is harder to compress and melt thick ice than thin ice – so the thickness of the ice is important. It is too early to determine if 2010 will see winds like 2007, or if summer winds this year will be more like 2006.
No one has demonstrated much skill at forecasting winds six weeks in the future, so it is really anybody’s guess what wil happen this summer. Before August arrives, the pattern should be clear.
The video below shows ice movement near Barrow, AK over the past 10 days.
The winds were blowing strongly and contracting the ice edge until the last few days, when they died down. Over the past two or three days, the ice edge has not moved very much.
Over the last week, almost all of the ice loss in the Arctic has been in the Hudson Bay, as seen in the modified NSIDC image below in red. The Hudson Bay is normally almost ice free in September, so the recent losses are are almost meaningless with respect to the summer minimum.
The modified NSIDCimage below shows ice loss since early April. All of the areas shown in red are normally ice free in September.
The modified NSIDC image below is a comparison of 2010 vs 2007. Areas of red had more ice in 2007. Areas of green have more ice in 2010.
‘
The modified NSIDC image below shows the current deficiencies in red. Again, all of those areas are normally ice free in September, so they don’t tell us much about the summer minimum.
Below is my forecast for the remainder of the summer.
But it all depends on the wind.
From the 9th century to the 13th century almost no ice was reported there. This was the period- of Norse colonization of’ Iceland and Greenland. Then, conditions worsened and the Norse colonies declined. After the Little Ice Age of 1650 to 1840 the ice began to vanish near Iceland and had almost disappeared when the trend re versed, disastrously crippling Icelandic fisheries last year.
The thick ice that has for ages covered the Arctic Ocean at the pole has turned to water, recent visitors there reported yesterday. At least for the time being, an ice-free patch of ocean about a mile wide has opened at the very top of the world, something that has presumably never before been seen by humans and is more evidence that global warming may be real and already affecting climate. The last time scientists can be certain the pole was awash in water was more than 50 million years ago.
Is it possible that the IPCC is trying to rewrite the history books?
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Phil. says:
June 29, 2010 at 7:48 pm
The Nares strait is very interesting, in most years it is blocked off by ice until late in the summer, when some ice floes (the thickest ice in the Arctic) leak out into the Baffin Sea where it later melts. One of the unusual factors of summer 2007 was that the Nares strait opened very early and much more ice escaped. The same thing happened this year and ice has been flowing out all spring.
Phil, Doesn’t surprise me it has been warm up there all winter and spring, perhaps we will get a large collapse again like last year?
Have you seen current temps at Resolute? http://www.weatheroffice.gc.ca/city/pages/nu-27_metric_e.html
NW passage open by the northern route? I still think both NW and N (NE) passages will be open again this year, is that 2 or 3 years now in a row?
Andy
Just The Facts says:
June 29, 2010 at 6:46 am
Looking back at some of the historical SST anomalies 2010 appears to be the coldest around Antarctica that its been in the last decade:
Do you concur?
No I don’t actually, I think looking and comparing images like that just confirms the bias of the viewer because I read it the other way! Also, after thinking about it for some time, I am not sure how much sea temps actually effect the maxima for Antarctica due to the fact that the Southern Ocean wind strengths are so large, I think that is the limiting factor in the main.
Andy
Correct me if I’m wrong, but it’s possible that the Arctic ice isn’t actually melting – it could be doing what it did in 2007 – the wind is compressing the ice – essentially stacking it up….
Pamela Gray,
Here’s my prediction for the year, less than 5×10^6 km2.
Based on gut feeling :p . Ok, due to the fact that the winter was warm due to the AO up there, it’s still warm up there and there has been a lot more clear sunny days up to now this year than last at the “North Pole” webcam. Nares straight is open so ice being lost that way, and I expect if 2010 is like 2007 then the ice may well be pushed north again by winds from the Siberian side which will melt it in situe and keep the extent low.
What’s your guess and why?
Andy
Pamela:
… I posted a Formal Outlook, 1 of 16 in the World, so I am already on the Spot:
MY CAUSE:: this year’s El Nino makes for a HUGE MELT.
…. think of it as a “Warmth Storm”, like 2007 but worse. Actually the most Significant thing about the 3 Open Water patches I keep harping on, is that they are in the SAME 3 PLACES as in 2007’s “Great Melt-Off.”.
IF WRONG – – the Reason will be More CLOUDS than 2007
.
Let me quote all of their Summary of my submission (read the rest in: http://www.arcus.org/files/search/sea-ice-outlook/2010/06/pdf/pan-arctic/wilsonjuneoutlook.pdf: )
“Wilson (No organization provided); 1.0 Million Square Kilometers; [Methods = ] Statistical and Heuristic
2007’s El Nino did three things to melt off 40% of ice volume relative to 2006:
(1) 2007 was hot, 2010 was more so; December was the highest monthly anomaly ever, February was 4th highest, March 10th highest, April 7th highest and the warmest April ever (these are figures from the Satellite (uah) Lower Troposphere breakout for N. Polar OCEAN).
(2) Winds pushed ice, though this will be critical mainly in July. 2007 and 2010 are unique in breaking the Nares Ice Dam, and 2010 broke it much worse.
(3) Cloudiness was 16% less than norm; if I am wrong, it will be here.”
I wish they’d put in my simple equation: Last Year’s Minimum Ice, Minus the Ice melted over the previous Minimum by 2007’s 1.1 El Nino, times the ratio of the 2 El Ninos:
5800 km3 – ( 4000 x 1.8/1.1 ) = -545 … i.e. it melts off, and: EARLY.
Charles Wilson, don’t you think that estimate is rather on the low side? The authors of the formal outlook seem to as they wrote;-
“With 16 responses, the June Outlook reflected both these arguments. The range of June Outlook estimates is 4.2 to 5.7 million square kilometers, with an additional estimate of 1.0 million square kilometers (Figure 1, below).”
So they seem to be grouping yours in it’s own class !
Are you just an amateur enthusiast ?
Andy
According to JAXA and some other sources sea ice extent is very low on arctic this year and high on antarctic.
I wonder if this has something to do with it:
“06 April 2009
Tie points Used in Algorithm May Result in a Relative Change in Sea Ice Area and Extent Two recent improvements in tie points used in the AMSR-E standard sea ice concentration algorithm may result in a relative change in sea ice area and extent for users working with multiple versions of the data. The effect on the output depends on season and hemisphere, but users may notice a decline in area and extent across the Arctic and an increase in the Antarctic in data with the most recent algorithm. The algorithm changes are reflected in the change from versions B06 to T08 and T08 to V10.
AMSR-E Level-3 sea ice products using the standard sea ice concentration algorithm include the following:
•AMSR-E/Aqua Daily L3 12.5 km Brightness Temperature, Sea Ice Concentration, & Snow Depth Polar Grids (AE_SI12)
•AMSR-E/Aqua Daily L3 25 km Brightness Temperature & Sea Ice Concentration Polar Grids (AE_SI25)
NSIDC encourages users to always work with the latest data (highest version number) available for a given date. Data from 19 June 2002 (start of the AMSR-E mission) to 26 January 2009 will be reprocessed to V10. We will send an announcement when reprocessing begins. More information on versions of AMSR-E data is available at the AMSR-E Versions Web page.
I wonder if JAXA has re-prosessed all years from 2002 and updated the graphics accordingly.
http://nsidc.org/data/amsre/news.html
I’ve been curious about Southern Ocean temperatures because they are consistently “blamed” for the Antarctic Peninsula’s high warming rate. That’s why I’m checking this.’
Causes of Antarctic Peninsula Warming
“The processes that might lead to the warming are not entirely clear; but warming,
does appear to be correlated with atmospheric circulation [van den Broeke and
van Lipzig, 2003], and particularly with changes in the Southern Annular Mode
caused by anthropogenic influence [Marshall, et al., 2004]. The winter warming
on the west coast also appears to be related to persistent retreat of sea ice
in the Bellingshausen Sea [Parkinson, 2002], and warming of the nearby seas
[Meredith and King, 2005]. The spring depletion of ozone over Antarctica
(the Antarctic Ozone Hole) has also been implicated [Thompson and Solomon, 2002]
in driving circulation change, but this has also been disputed [Marshall, et al., 2004].
While substantial recent progress has been made, current General Circulation Models
(GCM) do not, however, simulate the observed warming in this area over the past
50 years [King, 2003] and until the past warming can be properly simulated, there
is little basis for prediction that rapid warming will continue in future. This
in turn limits our ability to predict the future biological and physical impacts.”
Intriguing, the observations show warming, the models don’t.
Refer to Figure 7 of the Gille paper. The Antarctic Peninsula is located
approximately 70 deg. W (-70). This figure indicates warming in excess of
0.03 deg C per year at that longitude, down to at least 200 meters depth, and
the data extends back to the 1930s, according to the text. The analyzed latitude
is 55-60 degrees North, as this analysis is for the Antarctic Circumpolar Current.
Meredith, M. P., and J. C. King (2005), Rapid climate change in the ocean west of the
Antarctic Peninsula during the second half of the 20th century, Geophys. Res. Let., 32.
Abstract:
“The climate of the Western Antarctic Peninsula (WAP) is the most rapidly changing
in the Southern Hemisphere, with a rise in atmospheric temperature of nearly 3°C
since 1951 and associated cryospheric impacts. We demonstrate here, for the first time, that the adjacent ocean showed profound coincident changes, with surface summer temperatures rising more than 1°C and a strong upper-layer salinification.
Initially driven by atmospheric warming and reduced rates of sea ice production,
these changes constitute positive feedbacks that will contribute significantly to
the continued climate change. Marine species in this region have extreme sensitivities
to their environment, with population and species removal predicted in response to very small increases in ocean temperature. The WAP region is an important breeding and nursery ground for Antarctic krill, a key species in the Southern Ocean foodweb with a known dependence on the physical environment. The changes observed thus have significant ecological implications.”
M.J. Whitehouse, M.P. Meredith, P. Rothery, A. Atkinson, P. Ward, R.E. Korb, Rapid warming of the ocean around South Georgia, Southern Ocean, during the 20th century: Forcings, characteristics and implications for lower trophic levels, Deep Sea Research Part I: Oceanographic Research Papers, Volume 55, Issue 10, October 2008, Pages 1218-1228.
Abstract
“The Southern Ocean is known to have warmed considerably during the second half of the 20th century but there are few locations with data before the 1950s. In addition, assessments of change in this region are hampered by the strong seasonal bias in sampling, with the vast majority of data collected during the austral summer. However, oceanographic measurements near South Georgia span most of the last century, and we here consider almost year-round data from this location over an 81-year period (1925–2006). We observe significant warming between the early and late 20th century, with differential warming between summer and winter months and an indication that late 20th century summer temperatures peaked ~6 days
earlier. To quantify the long-term warming trend in this highly variable data, a mixed model utilising a Residual Maximum Likelihood (REML) method was used. Over the 81-year period, a mean increase of ~0.9 °C in January and ~2.3 °C in August was evident in the top 100 m of the water column. Warming diminished below 100 m and approached 0 at 200 m. Thus the long-term warming around South Georgia is substantial—more so than documented previously for the circumpolar warming of the Southern Ocean. We examine potential causal effects of this trend, including local atmospheric and cryospheric change, the influence of upstream waters and the role of coupled modes of climate variability such as El Niño/Southern Oscillation and the Southern Annular Mode (SAM). It is likely that all of these play a part in the
observed temperature increase. However, the role of the SAM is strongly indicated, via its likely role in the circumpolar warming trend in the Southern Ocean, and also by the atypical response of the South Georgia region to changes in heat fluxes associated with the SAM. Furthermore, the combination of a regional decline in ice extent and strong upstream warming likely explains a significant part of the strong seasonal variation apparent in the warming trend. In addition, we consider the implications that long-term warming has for South Georgia’s lower trophic levels. For Euphausia superba, at their northern limit, we find a significant negative relationship between summer South Georgia water temperatures and mean summer density of E. superba across the southwest Atlantic sector of the Southern Ocean. Simple abundance and growth rate relationships with our long-term temperature data appear to show declining habitat suitability for E. superba. In contrast, the warming trend is likely to favour other macro- and mesozooplankton species that occupy the more northerly parts of the Antarctic Circumpolar Current, and it is likely to promote phytoplankton growth.”
Based on the above references, I submit that the ERSST shown by GISS is not capturing a trend observed by several independent researchers and ascertained by a variety of methodologies. On this basis your “strike two” might be a candidate for being struck itself. It is peripheral to your primary thesis and thus the erroneous nature of this statement detracts from the general overall agility of the presentation.
MAK says:
June 30, 2010 at 2:15 am
According to JAXA and some other sources sea ice extent is very low on arctic this year and high on antarctic.
. . . . . . . . . . .
I wonder if JAXA has re-prosessed all years from 2002 and updated the graphics accordingly.
http://nsidc.org/data/amsre/news.html
Per your link, but higher up (date-wise);
13 May 2009
Reprocessing has Begun for AMSR-E Level-3 Land, Sea Ice, and Snow Data Products
Reprocessing has begun for the following AMSR-E Level-3 data products:
Land Product
AMSR-E/Aqua Daily L3 Surface Soil Moisture, Interpretive Parameters, & QC EASE-Grids (AE_Land3)
Algorithm: Validated 06
Sea Ice Products
AMSR-E/Aqua Daily L3 6.25 km 89 GHz Brightness Temperature Polar Grids (AE_SI6)
AMSR-E/Aqua Daily L3 12.5 km Brightness Temperatures, Sea Ice Concentration, & Snow Depth Polar Grids (AE_SI12)
AMSR-E/Aqua Daily L3 25 km Brightness Temperatures & Sea Ice Concentration Polar Grids (AE_SI25)
Algorithm: Validated 10
Snow Products
AMSR-E/Aqua Daily L3 Global Snow Water Equivalent EASE-Grids (AE_DySno)
AMSR-E/Aqua 5-Day L3 Global Snow Water Equivalent EASE-Grids (AE_5DSno)
AMSR-E/Aqua Monthly L3 Global Snow Water Equivalent EASE-Grids (AE_MoSno)
Algorithm: Validated 09
Data from 19 June 2002, the date the AMSR-E mission began, through the present will be reprocessed. Another announcement will be sent when reprocessing is complete.
___________________________________________________________
They started reprocessing 13 May 2009
They complted reprocessing on 27 July 2009;
Reprocessing Complete for AMSR-E Level-3 Land, Sea Ice, and Snow Data Products
Reprocessing is now complete for the following AMSR-E Level 3 products:
Land Product:
AMSR-E/Aqua Daily L3 Surface Soil Moisture, Interpretive Parms, & QC EASE-Grids (AE_Land3)
Algorithm: Validated 06
Sea Ice Products:
AMSR-E/Aqua Daily L3 6.25 km 89 GHz Brightness Temperature Polar Grids (AE_SI6)
AMSR-E/Aqua Daily L3 12.5 km Brightness Temperatures, Sea Ice Concentration, & Snow Depth Polar Grids (AE_SI12)
AMSR-E/Aqua Daily L3 25 km Brightness Temperatures & Sea Ice Concentration Polar Grids (AE_SI25)
Algorithm: Validated 11
Snow Products:
AMSR-E/Aqua Daily L3 Global Snow Water Equivalent EASE-Grids (AE_DySno)
AMSR-E/Aqua 5-Day L3 Global Snow Water Equivalent EASE-Grids (AE_5DSno)
AMSR-E/Aqua Monthly L3 Global Snow Water Equivalent EASE-Grids (AE_MoSno)
Algorithm: Validated 09
All data from 19 June 2002, the beginning of the AMSR-E mission, through the present now use the most up-to-date algorithm. For more information regarding the algorithm history of AMSR-E products, refer to the Data Versions for V002 Web page. For data access and documentation, visit the Data Summaries Web page
___________________________________________________________
They updated to V12 on 02 April 2010;
V12-Stage 1 AMSR-E Level-3 Sea Ice Products Now Available
NSIDC is pleased to announce the release of Validated 12 (V12-Stage 1) AMSR-E Level-3 sea ice products. The V12 algorithm corrects an error in the method for applying the multi-year sea ice mask that had caused large areas of Arctic to be erroneously masked in the Snow Depth on Sea Ice parameter. The multi-year sea ice mask and the snow melt mask are now stored within the AMSR-E/Aqua Daily L3 12.5 km Brightness Temperature, Sea Ice Concentration, & Snow Depth Polar Grids (AE_SI12) product. The AE_SI12 product is the only sea ice product with the Snow Depth on Sea Ice parameter, but all AMSR-E sea ice products use the same production code and therefore will be processed with the V12 algorithm.
AMSR-E Level-3 sea ice products include the following:
AMSR-E/Aqua Daily L3 6.25 km 89 GHz Brightness Temperature Polar Grids (AE_SI6)
AMSR-E/Aqua Daily L3 12.5 km Brightness Temperature, Sea Ice Concentration, & Snow Depth Polar Grids (AE_SI12)
AMSR-E/Aqua Daily L3 25 km Brightness Temperature & Sea Ice Concentration Polar Grids (AE_SI25)
NSIDC encourages users to always work with the latest data/highest version number available for a given date. The AMSR-E Science Investigator-led Processing System (SIPS) has begun reprocessing data, and NSIDC will notify data users when reprocessing is complete. Forward processing will begin once reprocessing is complete.
_____________________________________________________________
Methinks that one should read the entire page before cherry picking.
AndyW says:
June 30, 2010 at 1:05 am
Andy, I notice that despite his undertaking to you Steve McI didn’t come up with a new thread.
EFS_Junior says:
June 30, 2010 at 6:58 am
“Methinks that one should read the entire page before cherry picking.”
NSIDC’s sea ice product and JAXA’s web pages are two different animals. The question is not about reprocessing of the original sea ice products (yes, they have done that), but if JAXA has also reprocessed the sea ice graphics using the new sea ice data products or not.
I don’t recall seeing any updates to earlier years except of smoothing the June data – that was done earlier this year, I think.
My prediction is at least 2 weeks away. I am at my ranch in a remote area of NE Oregon and am on dial up (approx 40kbps and I get kicked off about every 10 minutes). That means that current online information is not available to me unless I want to sit in front of the ‘puter instead of out checking my stock water flow. I have wireless on order but there is a three week waiting list.
I am wondering about the changed algorithm we heard about earlier that removed the blip used to compensate for satellite confusion on melt ponds above the ice versus open ocean. The steep decline began right where the blip was removed. Just a thought but not a part of my thoughts about September minimum at the moment.
addendum re the algorithm. It would be interesting to see what the graphs looked like using last year’s version of ice melt algorithms.
MAK says:
June 30, 2010 at 7:33 am
EFS_Junior says:
June 30, 2010 at 6:58 am
“Methinks that one should read the entire page before cherry picking.”
NSIDC’s sea ice product and JAXA’s web pages are two different animals. The question is not about reprocessing of the original sea ice products (yes, they have done that), but if JAXA has also reprocessed the sea ice graphics using the new sea ice data products or not.
I don’t recall seeing any updates to earlier years except of smoothing the June data – that was done earlier this year, I think.
____________________________________________________________
The only way to find out, is to dig up older JAXA data, I know I had last season’s JAXA melt season data, somewhere on my ~dozen+ HD’s/flash drives.
Given the time, I’ll see if that older JAXA data can be resurrected, and post what I find, others here may also have older JAXA datasets.
Pamela Gray says:
June 30, 2010 at 8:04 am
I am wondering about the changed algorithm we heard about earlier that removed the blip used to compensate for satellite confusion on melt ponds above the ice versus open ocean. The steep decline began right where the blip was removed. Just a thought but not a part of my thoughts about September minimum at the moment.
Bear in mind that the blip was also removed from all the previous years as well. Also other algorithms (NSIDC, CT) which never produced such a blip and therefore didn’t make any change still show the decline.
In regards to Antarctic sea ice….
The AAO (the Antarctic Oscillation defined as the leading principal component of 850 hPa geopotential height anomalies south of 20S via Thompson and Wallace 2000 and is basically the same as the SAM-Southern Annular Mode) http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao_index.html has been strongly positive the past two months as the sea ice anomaly has grown. This supports the Ekman forcing argument that scientists have linked to increases in Antarctic sea ice.
What do you think of the 7-day forecast for this town on the Russian arctic coast?
http://www.wunderground.com/cgi-bin/findweather/getForecast?query=cherskij,%20russia&wuSelect=WEATHER
Pamela Gray says:
June 30, 2010 at 8:04 am
“My prediction is at least 2 weeks away. I am at my ranch in a remote area of NE Oregon and am on dial up (approx 40kbps and I get kicked off about every 10 minutes). That means that current online information is not available to me unless I want to sit in front of the ‘puter instead of out checking my stock water flow. I have wireless on order but there is a three week waiting list.”
You seem to have enough bandwidth to be able to demand and check other peoples guesses for the year but then have “other factors” that stop you posting a guess.
I think you just like stirring the pot rather than pissing in it. Either put your money where your mouth is or desist you demands on other posters here. Waiting 2 weeks to gamble, that is hardly impressive….
I said sub 5.0 and explained why, feel free to do likewise. NOW.
Andy
Pamela said
“The steep decline began right where the blip was removed. Just a thought but not a part of my thoughts about September minimum at the moment.”
I have a 100% accurate record on sea ice minimum. Mind you, some say its cheating not to forecast it until October 🙂
tonyb
Gavin,
If your prediction that 2010 minimum will be less than 2007 doesn’t happen are you going to come back to this blog and say you were wrong?
“In three days, the slope of the Arctic extent graph will begin to drop off.
Mark it on your calendar.”
It looks as though you have been proven correct here, steven goddard. JAXA is reporting that the melt has stalled, with a provisional daily figure of loss of just 46,875 square kilometres, and this will likely be revised downwards (these provisional figures usually are). Well done. 🙂
Out of curiosity, do any of you know how to do real statistical analysis? After centuries of there being no Northwest Passage since Henry Hudson first looked for it, we are very likely to have a Northwest Passage for the third year out of four. The year there wasn’t a Northwest Passage, there was a Northeast Passage, something that has also not been reported.
What are the odds on this being pure weather and not climate. I can calculate that; can you?
Dan M.,
I would be very interested to learn how to do that. Intuitively, such a distribution would seem unlikely to be weather, but I am unsure of how to calculate chances of the distribution being a random one.
AndyW says: June 29, 2010 at 10:33 pm
“No I don’t actually, I think looking and comparing images like that just confirms the bias of the viewer because I read it the other way!”
But if you look at how low the mint and aquamarine colors extend down on the historical map versus the current maps, there’s clearly been a precipitous decline… Kidding 🙂 Could be a bit of confirmation bias, but I still see some colder temps. When I have time I will see if I can get these maps quantified, maybe average temps below the 59th and 60th southern parallels.
Julienne says: June 30, 2010 at 12:10 pm
“In regards to Antarctic sea ice….
The AAO (the Antarctic Oscillation defined as the leading principal component of 850 hPa geopotential height anomalies south of 20S via Thompson and Wallace 2000 and is basically the same as the SAM-Southern Annular Mode) http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao_index.html has been strongly positive the past two months as the sea ice anomaly has grown. This supports the Ekman forcing argument that scientists have linked to increases in Antarctic sea ice.”
Your presence here is most welcome. I’ve done some prelim research on the AAO and will study and track it with interest.