What happens to Steig et al’s warming when you divide Antarctica into two distinct climate zones?

A week ago I made this comment to Jeff Id on The Air Vent regarding his reconstruction of the Steig et al Antarctic temperature trends paper. The idea was to treat Antarctica as two distinct climate zones. I should point out that this idea has not been accepted yet, but there are some good reasons to consider it.

Köppen world climate classification

Köppen world climate classification

As seen in the map above, currently Antarctica is classified per the Köppen climate classification system entirely as EF, or “Ice Cap”. But here is what it might look like if the peninsula was classified differently.

antarctic_climate_zones1

I’ve made some enhancements with inline images and links to my original comment on The Air Vent for WUWT readers:

Jeff, in looking at your output maps above something occurred to me about the climate the Antarctic peninsula.

The biggest problem I see with Antarctica in either yours or Steig’s reconstructions is the treatment of the continent as a single climate zone, when in fact the climate of the peninsula has a significantly different set of temperature and precipitation norms than the majority of the main continent.

Going back to basic climatology one can recall the Köppen climate classification system. Antarctica has been classified as EF

EF =Ice Cap Climate – All twelve months have average temperatures below 0 °C (32°F) There has been some discussion that the Aleutian peninsula might be better served if newly classified as EM (Maritime Polar) This would separate relatively mild marine locations such as Ushuaia, Argentina and the outer Aleutian Islands like Unalaska The climate of Unalaska from the colder, continental climates. The mean annual temperature for Unalaska is about 38 °F (3.4 °C), being about 30°F (−1.1°C) in January and about 52°F (11.1°C) in August. With about 250 rainy days a year.

Contrast that to interior Alaska temperatures which are not moderated by the presence of the sea. Fairbanks for example has an mean annual temperature for Fairbanks is 26.9°F (-2.8°C) and with 106 rainy days.

Using the Unalaska to Fairbanks comparison, the Antarctic peninsula would be a candidate for this new “Maritime Polar” (EM) classification IMHO.

In support of that, here is a seasonal temperature map submitted to Wikipedia by Stoat’s William Connelly:

Antarctic surface temperature from ECMWF (era40) reanalyses, 1979-2001.

Antarctic surface temperature from ECMWF (era40) reanalyses, 1979-2001.

Note how in winter the Antarctic peninsula is completely at the other end of the temperature scale from the interior just as we see in the Unalaska to Fairbanks comparison. In the summer, the effect is less, but the Antarctic peninsula agrees mostly with the sea temperature band surrounding the Antarctic continent.

Another piece of support evidence that the Antarctic peninsula climate is vastly different than the interior continent is precipitation, the other half of the Köppen climate classification system.

Here is a map of Antarctic precipitation:

Map of average annual precipitation (liquid equivalent, mm) on Antarctica

Map of average annual precipitation (liquid equivalent, mm) on Antarctica

Note once again that in terms of precipitation the Antarctic peninsula climate is also vastly different than the interior continent. It seems the Antarctic peninsula is an outlier when compared to the rest of the continent. The peninsula gets 400-600+ mm of precip while the interior gets 0-100mm.

As Köppen understood, places that are connected geographically and politically aren’t always connected by a common climate. Note another factor that you pointed out in this article:

http://noconsensus.wordpress.com/2009/02/15/aws-gridded-reconstruction/

Note that we have the majority of weather stations in Antarctica on the peninsula in your grid cell C, a total of 11. No other place in Antarctica comes close in the number of weather stations. Further, that grid cell also happens to be the one where the climate diverges from the interior of Antarctica the most.

So why is the obviously different Antarctic peninsula climatic zone being considered in the Steig study at all? The answers are: 1) it is connected geographically to the continent so that when saying “Antarctica is warming” the statement is true. 2)Treatment of the Antarctic peninsula climate zone as an outlier likely ruins the premise of the study in the first place.

Of course the counter argument would be that: “Antarctica is classified as one climate zone, thus our analysis in robust” but my counter argument would be that we could also likely find the same results from a study of the USA if we had the majority density of weather stations in the study based in the Florida keys and south Florida, with a remainder around the coastal cities of the USA and maybe a few in the interior. Could we accurately derive the climate trend of the USA from such and arrangement? Me thinks not.

To test this, I’d like to see what happens when the interior and the peninsula are are treated as separate climate zones. You could pick a delineation line right at the base, or go further out the peninsula, I doubt it would make much difference given the station weighting. Produce separate outputs showing the continent versus the peninsula.

I’ll bet the results will be obvious and telling.

Well, Jeff obliged and did the analysis I suggested. I thank him for that. While the decadal temperature  trend does switch from positive to negative, there is some new information that has emerged about the RegEM analysis.

Spatially Weighted Antarctic Temperatures – No Peninsula

Posted by Jeff Id “The Air Vent” on April 18, 2009

From this post and others I’ve determined that the temperature trend in the RegEM versioins of the Antarctic are not entirely created by smearing of the peninsula station’s data.

In order to interpret the RegEM results from the previous peninsula free reconstruction, we need to see a baseline reasonable reconstruction without the peninsula. These trends are based entirely on the surface station data. I saw several questions on WUWT about the improved accuracy of satellite temperatures. The satellite temperatures in this paper are of a different type than UAH or RSS use and these are affected substantially by clouds. The result is a much noisier and less trustworthy dataset than surface measurements.

In my opinion this sort of thing is about the best we can do in determining a total trend for the Antarctic over this timeframe. There are a few tweaks which might help but beyond that we have to accept that we don’t know any better than this method shows.

Now removing the peninsula does have basis in science because the ultra thin strip of land is primarily dependent on ocean temperatures and currents. It will be seen as cherry picking because I’ve clipped the part of the Antarctic warming the most. Before TCO or someone points out that I wouldn’t clip it if it didn’t have warming, keep in mind that I show it both with and without the peninsula and I make no claim that clipping the peninsula is the preferred method. It does make some sense though.

First the full trend.

nop-id-recon-total-trend

Figure 1

Spatial trends with clipping region shown in black Figure 2.

Figure 2

Figure 2

As I’ve shown before, the trends from 1967 onward.

Figure 3

Figure 3

Spatial distribution 1967 onward.

Figure 4

Figure 4

If I’ve learned anything from all these plots, it’s that the Antarctic isn’t warming at 0.12 +/- 0.7 C/decade. It just isn’t. The actual trend is much lower than that and since 1967 it has even dropped a little across the continent.

Now from the other reconstructions we have the following.

trend-table

Compared to the 0.12 that Steig et al. claims the real trends are pretty low. When the peninsula is removed in the properly weighted reconstruction presented here the trend drops by(0.52-.39)/.52 x100 =25%. This represents a very large contribution to the average simply because this tiny area has shown so much warming. It doesn’t seem reasonable to adjust the continent upward 25% based on this little strip of land.

Surprisingly, in RegEM the trend changes by an similar amount (0.108-0.074).0.08 x100 =31%. This is impressively similar to me as many have speculated that the positive trend in RegEM is created by smearing of peninsula trends. In my spatial reconstruction above, there is no smearing of the peninsula trend at all and there is a 25% trend drop when the peninsula is removed. This means to me that the RegEM high positive trend is not wholly created by the peninsula. Also, this does not mean the trends aren’t smeared by RegEM, they are.

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64 thoughts on “What happens to Steig et al’s warming when you divide Antarctica into two distinct climate zones?

  1. It would also matter as to the circulation of the ocean current that winds around this continent (the only ocean current that circles the globe). Arctic ice climate patterns (note the plural form) depends very much on where each ice area is in the ocean circulation patterns in that confined space, along with proximity to land. Your idea of climate zones in Antarctica should be fairly easy to delineate by using something similar to how the Arctic is done.

  2. The simplest, and perhaps so simple it is incorrect, explanation of the error in Steig et al is that he, or one or more of his co-authors, illicitly used statistics to spatially smear peninsular warming over the rest of Antarctica and temporally smear old warming into the present. The paper should be withdrawn. It is that bad.

    Kevin Trenberth, hardly a climate skeptic, nailed the problem early on when he said that it is hard to make up data.
    ==========================================

  3. You wrote:

    “Of course the counter argument would be that: “Antarctica is classified as one climate zone, thus our analysis in robust” but my counter argument would be that we could also likely find the same results from a study of the USA if we had the majority density of weather stations in the study based in the Florida keys and south Florida, with a remainder around the coastal cities of the USA and maybe a few in the interior. Could we accurately derive the climate trend of the USA from such and arrangement? Me thinks not.”

    My question is: Is the US data available to do it? If so, why don’t you do it? If not you, then perhaps the Jeffs or Steve M. Someone should do exactly the study you are proposing, treating the US exactly the way Steig has treated Antartica, and let’s see what the results are. Pick a bunch of weather stations in south Florida, a few along the coasts, add in Chicago and maybe Kansas or whatever would be comparable to the data we have for Antartica. Run the same program on the US data that Steig ran on Antartica. The results would be quite humorous, and would tend to undermine the credibility of Steig et al.

  4. You only have to look at a map and see how the Antarctic Peninsula and tip of South America squeeze the ocean currents to know that both regions are vastly affected by the ocean temperature. It is the same in the UK where the Atlantic currentsaffect the climate around the south-west and western parts. They are a lot milder in winter and not so hot (warm!) in summer as the centre and east.

  5. Thanks again to Anthony for running this post. For those who are trying to interpret the meaning as far as the Steig reconstruction is concerned this is a key.

    “the RegEM high positive trend is not wholly created by the peninsula.”

    I believe it is a combination of the peninsula, PCA with too few components, processing of cloud data and spurious trend spreading based on negative correlation.

    In each step listed here, there was an increase in trend.

    1 – TIR sat data (not the same as UAH microwae) has higher trend than surface station

    2 – PCA breakdown of TIR data results in increased trend. It’s mathematically valid and could have decreased the trend but it didn’t. The validity of 3pc’s is in question.

    These two above steps are important because they represents 100% of the RegEM reconstruction after 1982.

    3 – RegEM with regpar=3 smears trends and causes spreading and ‘flipping’ of trend signals. The flipping could have done anything, but in this case it resulted in an overstated trend.

    As before with Mann08, every detail which is wrong is wrong in the direction of increased warming. — I’m not too sure about WUWT policy on speculation regarding this so please be soft worded.

    4 – Peninsula stations result in 25% of the positive trend in both reconstruction methods. I originally jokingly referred to the red spot in the Antarctic as the scientist locater, because of the density of scientists in the peninsula.

  6. “My question is: Is the US data available to do it? If so, why don’t you do it? “

    Thanks TA, my thoughts exactly.

    I suspect however that Hansen is already doing this.

  7. I believe it is justified based on this animation of cloud movements and winds over one year.

    The Antarctic Pennisula is outside of (at the edge of) the south polar vortex and has more in common with the tip of South America than the interior of Antarctica for example.

    https://www.ucar.edu/publications/nsf_review/animations/ccm3.512×256.mpg

    There is, of course, long periods of time when the Atlantic side of the Pennisula is frozen sea ice so it is a frozen world for 9 months of the year (the Pacific side facing the warmer prevailing winds doesn’t get as much sea ice).

  8. Since Jeff mentioned it, as a resident of Florida and someone pretty interested in climate information from these parts, I can confirm that trying to derive the climate trends in the US with data in Florida would definitely be a bad idea, not least because of the heavy influence of land use changes on our regional climate here. We used to have nothing but totally unliveable swamp muck down here, now we have nothing but cities and agriculture. You better believe that is more important than anything CO2 might be doing down here.

    As far as this whole Antartica debacle goes, I think it is pretty clear that we are all quibbling over tiny trends. But Connolley’s graphs are misleading, IMHO-I first mistook them for trends, then thought it was rather odd that red was chosen to be colder than orange and yellow.

  9. As far as reconstructing the RegEM process from the US the difficulty is in obtaining TIR satellite data that has been processed for clouds. Comiso really did a lot of work to make this dataset appear usable. We could replace the TIR with the UAH microwave data however but the frequency dependent temperature multiplier can cause some trouble.

    As something to consider, when surface stations is complete and the best are chosen. We’ll have a more sparse set of surface stations which could be used uncorrected with area weighting as was done in this reconstruction to create a proper US trend.

  10. This is a really great post, taking subject matter that is rather esoteric and presenting it in such a cogent and easily apprehended fashion. After reading this, the idea of designating the peninsula as EM (Maritime Polar) becomes intuitively sensible. I’m sure we’d still hear about the doom awaiting us from collapsing ice shelfs, but it would be possible to mount a better defense, were the peninsula recognized as significantly different from the rest of the continent.

  11. Anthony,
    I have seen various claims of undersea volcanoes leading up to the Peninsula…..is this true?
    If so should not the water temp be higher than the other side of Antartica….or is the continent surrounded by volcanoes thereby having a general rather than localised effect?

    James

  12. The precipitation map is really interested even if you exclude the peninsula. Looking at Jeff’s grid with actual AWS locations, you notice that there are only two (maybe 3) AWS’s located in an area with less than 100mm of precipitation. Steig’s paper rests on the argument that the surface station data gives us a good model of spatial relationships between temperatures in Antarctica–along with the assumption that these spatial relationships hold over time. We need that assumption so that we can estimate what temperatures satellites would have recorded near the pole in the 50s and 60s, even though that data does not exist.

    How does that relationship even make sense if there are clear climactic differences between the internal areas of Antarctica and most of the coast, where most of our measurements were taken? Not to mention the whole mountain range in the middle. I’m increasingly skeptical that this spatial relationship makes enough sense to provide the precise measurement of warming that Steig concludes.

  13. Koppen is claimed to be a climatologist and botanist. His first classification (1884) was based on heat zones. Then he used a world vegetation map prepared by a French plant physiologist along with temperatures. Still later he lessened the role of plants and went to strict empiricism using temperatures and precipitation. Rudolph Geiger also contributed to their world map of climates; first wall map in 1928.
    It is a guess they were not particularly interested in the subtleties of Antarctica’s different geographic characteristics. Of if they were, they had very little information on which to carve it up climatically.
    Neither this classification, nor any other, ought to be considered sacred text. New insights and new and expanded data are legitimate reasons to adjust boundaries. Koppen and his students did this as a matter of record. Go for it.

  14. Interesting, enduser. It appears they are using a 15-year old picture, and pretending that it’s current.

    Also, every time I look at a map of the Antarctic peninsula pointing directly at Tierra del Fuego [“Land of Fire”], I think of the volcanic activity that takes place at the intersection of tectonic plates.

    And notice that the Antarctic peninsula is closer to South America than to the South Pole.

    • Smokey,

      In case you didn’t know, Tierra del Fuego was named for all the smoke rising from native campfires witnessed by European explorers, not for volcanic activity. The original inhabitants roasted a lot of mussels. I’ve hiked over those still existent mussel shell piles.

  15. With all that precipitation on a peninsula that is still below zero temp, no wonder the sea ice calves big time.

    Connolley’s graph is visually seriously misleading – all the Antarctica graphics have become progressively more and more misleading – by using bright red to represent sub-zero temperatures and (in other maps) tiny warming in an environment that is still way below zero. What does the average person imagine? Rommulan Antarctic cattle-grazing pastures rapidly becoming deserts?

    I’ve recoloured Connolley’s maps and when I get back to a broadband machine I’ll upload it so folk can see.

  16. It is evidently just about weather. Think it as the Florida peninsula, this is pointing to the equator, to the south,…see?, the equivalent of that for antactica is its Florida peninsula down there, this time also pointing to the equator north of it. No one would expect to compare, say Vermont´s weather with the Florida peninsula weather.
    This is but another invented issue to back silly GW, which backs not too silly but too “clever” carbon business, or rather carbon´s swindle.

  17. The antarctic peninsula, pointing to the equator, is for antarctica what Florida´s peninsula, pointing to the equator is for the USA. No one would compare Florida´s weather to Vermont´s weather.
    This is from another telltale, pass the word, conveniently written, or better concocted, to back silly GW, which in turn backs the not too silly but too “clever” carbon´s swindle.

  18. Britannic no-see-um,

    Thanks for that link. This particular graphic was interesting: click

    You can see that the Antarctic peninsula and South America were connected 200 mya, and have since been pulled apart.

  19. Increased Katabatic winds could account for the temperature changes in Figure 3 and 4, Has anyone looked into this? I saw a study a while back showing the effect on temperature with increasing Katabatic winds and recall those 2 areas showing warming were areas subjected to Katabatic winds. No time to look for it, just offering this as a possibility in case someone knows something about it.

  20. Dr. Bob Carter, in his speech before the 2009 International Conference on Climate Change – http://www.heartland.org/events/NewYork09/proceedings.html – stated that climate is local or regional, not global.

    I have posted before that the Western Garden Book identifies 24 climate zones in the western United States – west from Montana, Wyoming, Colorado and New Mexico.

    Why should it be a surprise to find two or more climate zones in the Antarctica?

  21. Thanks again jeff and Anthony, but I doubt there this obviously valid premise cannot be implimented because, as you say:
    “2)Treatment of the Antarctic peninsula climate zone as an outlier likely ruins the premise of the study in the first place.”

    enduser (12:09:06) Re: “I notice at NSIDC that the photo for Wilkins, 10 April 2009 ( MODIS visible) is exactly the same as the photo for AVHRR image (visible) 20 February 1994.” This does not seem to be the case. I captured the April 10 2009 and the February 20 1994 images. I scaled the 2009 image as closely as possible to the 1994 image (which I increased the contrast on), and labeled them respectively. See here: http://i44.tinypic.com/eknx5j.jpg

    Smokey When you just follow the link you get a location map that is dated 2003, you have to actually click ‘Show Image’ button to get the image for the date 10 April 2009. It is confusing, and had me going to.

  22. “Smokey When you just follow the link you get a location map that is dated 2003, you have to actually click ‘Show Image’ button to get the image for the date 10 April 2009. It is confusing, and had me going to.”

    What am I missing here?

    Smokey, it had you going?

    I still do not understand why NSIDC shows a 1994 picture and labels it April 10, 2009.

    Seriously, If I have made a mistake here, please tell me what it is. Original post follows:

    I notice at NSIDC that the photo for Wilkins, 10 April 2009 ( MODIS visible) is exactly the same as the photo for AVHRR image (visible) 20 February 1994.

    The very same photo. Please confirm that my eyes are not deceiving me.

    http://nsidc.org/data/iceshelves_images/wilkins.html

  23. James Griffin (13:21:22) :

    the peninsula is part of the Pacific ring of fire so it has many active and extinct volcanoes as does Chile and Bolivia to the north.

    In fact no one actually knows how many undersea volcanoes exist in the area because no one has looked.

    The South Sandwich islands, Decpetion, Bridgeman, Paulet and Penguin islands are all in the area and are active.

    Reply: Deception Island is a beautiful place. I’ve been there. Ready to eat boiled shrimp sometimes wash up on the shore. ~ charles the moderator

  24. Lucy Skywalker (14:38:35) It would be pretty silly to say “Antarctica is rapidly becoming a desert when it actually already is one!

  25. Charles – there must be undersea volcanoes if the shrimp come up boiled already :)

    Reply:The entire Island is a volcano. You sail into the caldera through a collapsed wall. ~ charles the moderator

  26. Well spotted Enduser.

    It makes you wonder just how many old photographs there are out there that are being recycled time after time claiming each time to be the latest, up to date, information.

    Enjoy.

  27. Antarctic weather is dominated by 2 different effects. One is the intense low pressure systems that constantly circle Antartica. The other is the very cold, very dry katabatic winds that blow out from the interior of Antarctica.

    Precipitation would be a good proxy for which dominates where. The precipitation map above shows high precipitation not only on the Peninsula but also along a large part of the edge of East Antarctica.

    If you want to separate Antarctica into 2 climate zones then I would include the parts of East Antarctica with precipitation over 600mm in the polar maritime zone. IMHO of course.

  28. Britannic no-see-um,

    those puzzle pieces really look like they fit well, that is, until you realize that you need to include the continental shelf areas for this type of fitting game.

    Purchase a cheap cardboard globe that shows shelf area, cut out the pieces, and see how well they fit that-a-way!! Doesn’t disprove anything as there could be many stretching/compression areas not easily identified, but, shows it just ain’t that simple!!

  29. Steve Keohane (15:48:56) :

    “Thanks again jeff and Anthony, but I doubt there this obviously valid premise cannot be implimented because, as you say:
    “2)Treatment of the Antarctic peninsula climate zone as an outlier likely ruins the premise of the study in the first place.”

    enduser (12:09:06) Re: “I notice at NSIDC that the photo for Wilkins, 10 April 2009 ( MODIS visible) is exactly the same as the photo for AVHRR image (visible) 20 February 1994.” This does not seem to be the case. I captured the April 10 2009 and the February 20 1994 images. I scaled the 2009 image as closely as possible to the 1994 image (which I increased the contrast on), and labeled them respectively. See here: http://i44.tinypic.com/eknx5j.jpg

    Smokey When you just follow the link you get a location map that is dated 2003, you have to actually click ‘Show Image’ button to get the image for the date 10 April 2009. It is confusing, and had me going to”

    REPLY:

    The picture that is retrieved for AVHRR visible image 20 February 1994 now is NOT the same picture that I retrieved earlier today! SOMETHING IS NOT RIGHT HERE!

    The picture that I retrieved earlier today for 20 February has been changed. I saved it, and have it available on my HD.

  30. C,mon somebody has to have these pictures archived on their computers.

    If I am telling the truth (and I am), then this is very serious.

  31. The summer/winter thermal graphs of Antarctica with temperature gradiants, gave me a picture of just how far cooling extended in the winter. Funny because I had just started wondering how many square Km of open Antarctic waters were exposed to cooling air and I see it here. Thanks for that.
    The whole story about polar contributions to climate change needs to include the cooling of sea water.

  32. janama (16:21:25) :
    Charles – there must be undersea volcanoes if the shrimp come up boiled already :)
    Reply:The entire Island is a volcano. You sail into the caldera through a collapsed wall. ~ charles the moderator

    You’re kidding right Charles? Is there a cocktail sauce fountain and a beer fountain there too, or do you bring your own?

  33. Congratualtions, Anthony? (it was you who posted the climate zone info?). this is really good thinking, and based on the evidence you presented, probably a very useful and realistic revision of the climatic classification of Antarctica. I think you should spruce it up and submit it to an appropriate scientific magazine or body for consideration.

    I had been thinking about writing something along similar but different lines. This just makes what I want to say easier. What we have in Ant. is two (at least) areas that are essentially different. Temperature data from one has no “statistical” correlation with the other(s) except by coincidence.

    Mining geologists have wrestled with similar issues for eons. They have a limited amount of assay data from drill holes and other sampling of a mineralized body. Now they have to make an “ore reserve” estimate in order to determine whether there is an economically feasible mining operation, and if so, then make a mining plan to direct the actual drilling/blasting/digging of rock, some of which gets milled, the rest gets dumped. Steig et al. were, in a sense, doing the “ore reserve”.

    If the ore deposit were relatively homogeneous, then one can reasonably infer that an assay here is related to one over there, and one can infer the ore content of the rock between the two (here is 1 ounce, there is 2 ounces. Halfway between should be 1.5 ounces, no?) Too often, deposits are not homogeneous. Geostatisticians have dealt with this issue for many years, and have developed techniques to cope with two or more populations of sample results.

    Basically, what they would do is to segregate the data for the high-grade vein deposit (West Ant.) from that for the much larger, more homogeneous porphyry copper deposit (East Ant.) and make the calculations – and ultimately – ore reserve estimates (temperature blocks/areas or trends, if you will) for the two areas independently.

    An approach to the “temperature trends” of the Antarctic following this school of statistics would have strong scientific underpinnings. Mixing the two, as both Steig and Id have done, simply is statistically invalid, and most likely, wrong.

  34. The idea of applying Steig’s method to America is interesting, and might be good for a laugh. Australia is similar in some aspects to Antarctica, size, interior different from the perimeter, etc, and might also be a good candidate.

  35. I have to laugh at calling Antarctica ‘one climate zone’.

    That’s like linking Alaska to California – when everyone knows that their climates aren’t linked closely.

    How about Britain to the Balkans?

    And Chukotka to inner Siberia?

    The reason most work is done on the Antarctic peninsula is:
    i. It’s accessible.
    ii. It’s less cold and frigid.
    iii. It shows what people want it to show.

  36. Jim F,

    Mixing the two, as both Steig and Id have done,

    You’ll notice I removed the peninsula in the above reconstruction to analyze temp trends. Ive done this in at least two other reconstructions as well. Also, Jeff C and I have provided several alternative reconstructions all based on improved localization of the temperature data.

    I agree Anthony’s suggestion is quite valid and at the same time I don’t agree that it is statistically invalid to consider both regions in total trend. If you want the temperature trend of the earth you don’t cut off bits. It’s important that the contribution of the different areas are properly weighted though.

    I think it would be hard for someone to argue that a reconstruction excluding the ocean controlled temperatures of the peninsula is invalid, so on that point we agree.

  37. Well, Last night I was ready to claim grand conspiracy, but having slept on it, and looking at the NSIDC site again, I can concede that the most likely thing that happened is that I selected Feb 20, 1994 on the AVHRR menu and accidentally hit the SHOW IMAGE tab for MODIS which was already set by default for Apr 10, 2009.

    Thank you for taking the time to correct me on this, I will go and hang my head in shame for a while….

    Unless…. [eyes narrowing and darting back and forth] You are ALL in on it! In which case I must go and make a tin foil hat.

  38. “Mike McMillan (00:07:22) :
    The idea of applying Steig’s method to America is interesting, and might be good for a laugh. Australia is similar in some aspects to Antarctica, size, interior different from the perimeter, etc, and might also be a good candidate.”

    I think BOM already has that covered.
    Mike

  39. It seems odd that the coldest temperatures in the Antarctic are offset to the East of the South Pole, and the Beaufort Gyre in the Arctic is offset to the West of the North Pole. It’s a nice little bit of symmetry there, but could it mean anything at all?

  40. Jeff Id: Sorry, I didn’t mean to tar you with the brush I would use for Steig. I think I had in mind and was referring to some earlier work you had done on Steig’s data, where you were folding all the data together. I appreciate too that above you have separated the data sets. My apologies for sloppy writing.

    I agree that to get an idea/estimation of the Earth’s climate trends and variability (or maybe Antarctica’s) one would use all the data. But to calculate an estimated temperature at point x, 200 miles thataway from measurements at points y and z, which is what Steig is doing, I think it wrong to mix the data if they are indeed different. The much higher temperatures measured on the Peninsula are relatively localized; they don’t have any effect on the temperatures way up on that mountain of ice called East Ant. Yet Steig’s approach smears a component of those warm results all across the continent. It’s no wonder Antarctica is heating up! ;)

  41. According to the World Climates link”E – Cold Climates … Only about four months of the year have above freezing temperatures.” but according to Connelly’s map even the summertime temperatures are below freezing for anything south of the tip of the Antarctic Peninsula.

    If we’re going to reclassify, shouldn’t there be a primary category F (temperatures below freezing almost year round) with subgroups M (maritime-high rainfall) and D(dry continental interior). These zones might also be applied to Greenland, depending on the precipitation pattern; anyone know when & how much snow falls on interior Greenland?

  42. Philip_B (17:47:48) :

    “Antarctic weather is dominated by 2 different effects. One is the intense low pressure systems that constantly circle Antartica. The other is the very cold, very dry katabatic winds that blow out from the interior of Antarctica.”

    These cold dry katabatic winds flow down from the higher elevations, 2 to 3 miles to the surface and actually warm as they descend, a source of warming at the surface.

    http://profhorn.aos.wisc.edu/wxwise/AckermanKnox/chap12/katabatic_winds.html

  43. jorgekafkazar re volcanism. True, there will be higher heat flow in parts of the volcanic belt in W. Ant. The effects however should be localized; there is such a stupendous amount of cold water impinging on this belt that there will probably be no measurable change in regional oceanic temperatures. Locally, like in a noted caldera, hot springs/lava flows may boil your shrimp dinner for you.

    However, other effects may be noticeable. Hot magma rises, forcing up rocks above it. This could dislodge chunks of ice sheets that apparently are anchored to rocks that the ice has depressed below sea level. Maybe some portions of ice will become dislodged and slide off the building mound. Similarly, lava and hot springs might melt those ice-rock joins, letting the ice float free.

    Much depends on time, first (these are generally slow processes) and second, the composition of the volcanism. Basalts don’t give much explosive activity (the magma has little silica in it, and so is relatively fluid). Andesitic to rhyolitic volcanism – much more siliceous – can result in explosive events, which might blast out a chunk of ice of considerable proportions.

  44. pft, what you say is true. However, to be warming toward the coast would require the lapse rate of the katabatic winds to be greater than temperature differential due to altitude, and that seems not to be the case.

    Ie, katabatic winds are colder than otherwise prevailing temperatures toward the coast.

    I just lost the link and my battery is about to run out. So you will have to take my word.

  45. Not only has this site some fantastic photos but lots and lots of data, volcanoes, volcanoes and more volcanoes, http://www.thewe.cc/weplanet/poles/antarcti/mastvolcanoe.html I would think that any serious study of the volcanic activity on the Antarctic Peninsula would show that it could not be part of any climate study of the Antarctic, think a little, 2km offshore and 2,800mt, water depth and boiling water on the ocean surface could not have any effect on the local climate [one of several] cauldrons off the Peninsula.

  46. More (unitentional) support for this thesis:

    http://www.newscientist.com/article/dn16988-why-antarctic-ice-is-growing-despite-global-warming.html

    pointing out that the antarctic peninsula isn’t like the rest of Antarctica…

    “In a new study, Turner and colleagues show how the ozone hole has changed weather patterns around Antarctica. These changes have drawn in warm air over the Antarctic Peninsula in West Antarctica and cooled the air above East Antarctica.”

    I like the ending “”Over the next 50 to 100 years, the ozone hole will heal,” says Turner. “At the same time, greenhouse gases will rise. In next decade or so we should see sea ice plateauing and then decreasing massively if greenhouse gases continue to increase.”

    I thought CO2/AGW caused ozone depletion, so how is this healing (sometime in the misty future) gonna happen?

  47. “Philip_B (17:30:44) :

    pft, what you say is true. However, to be warming toward the coast would require the lapse rate of the katabatic winds to be greater than temperature differential due to altitude, and that seems not to be the case.”

    Phillip, The followng paper is available online, no time to find link:

    “Climatology of katabatic winds in the McMurdo dry valleys,
    southern Victoria Land, Antarctica, Thomas H. Nylen and Andrew G. Fountain Department of Geology and Department of Geography, Portland State University, Portland, Oregon, USA, Peter T. Doran
    Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
    Received 1 July 2003; revised 16 October 2003; accepted 3 December 2003; published 14 February 2004.

    [1] Katabatic winds dramatically affect the climate of the McMurdo dry valleys, Antarctica. Winter wind events can increase local air temperatures by 30C. The frequency of katabatic winds largely controls winter (June to August) temperatures, increasing 1C per 1% increase in katabatic frequency, and it overwhelms the effect of topographic
    elevation (lapse rate). Summer katabatic winds are important, but their influence on summer temperature is less. The spatial distribution of katabatic winds varies significantly. Winter events increase by 14% for every 10 km up valley toward the ice sheet, and summer events increase by 3%. The spatial distribution of katabatic frequency seems to be partly controlled by inversions………..Although the onset and termination of the katabatic winds are typically abrupt, elevated air temperatures remain for days afterward. We estimate that current frequencies of katabatic winds increase annual average temperatures by 0.7 to 2.2C, depending on location. Seasonally, they increase (decrease) winter average temperatures (relative humidity) by 0.8 to 4.2 (1.8 to 8.5%) and summer
    temperatures by 0.1 to 0.4C (0.9% to 4.1%). Long-term changes of dry valley air temperatures cannot be understood without knowledge of changes in katabatic.”

    The study and effect was observed near the coast.

  48. The Climate of the Peninsula is akin to that of the Aleutian Islands, or, the northern Norwegian Sea coast of Norway. It is correct to split it from the main land mass.

  49. So the total climate temperature range on earth goes from 72F to -36F; a mere 108F total range.

    A really great classification system given that the actual measured range can be from +130F to -140 F, or +60C to -90C or 150 C (270F).

    And just a glance at the color map demonstrates clearly why it isn’t nice to ignore the Nyquist Sampling Criterion.

    So I guess it is nice to to have a system for describinh the weather on the nightly news; but anybody who thinks +72 F is hot is just plain nuts. I think it was around 90 today out in our parking lot; and it didn’t seem the boiling cauldron people think.

    The warmth I could feel was the direct IR radiation from the blacktop parking lot, and my lungs don’t care for the vertical hot air currents; but I’m supersensitive to that; but no way I would describe it as hot.

    George

  50. pft, the warming effect of katabatic in dry valleys appears to be a local phenomena and generally katabatic winds in Antarctica are cold winds, ie colder than the otherwise prevailing temperatures.

    http://en.wikipedia.org/wiki/Katabatic_wind

    Although, it does raise the question that if katabatic winds can produce substantial differences in temperatures as a result of local topography, then siting of the small number of, East Antarctica in particular, weather stations may well result in measuring trends in a local phenomena (katabatic winds) rather than ‘global’ climate effects.

  51. Philip_B (17:50:04) :

    Katabatic winds are heated adiabatically which is why the air and the valleys are dry. They may be cold, but they still tend to end up warmer than prevailing temperatures when they are most intense, especially in the winter. It is a local effect only to the extent that katabatic winds are limited by topography. Any short term warming may be a result of variations in the intensity of these winds from year to year, especially if weather stations happen to be located nearby.

    Anyways, here is that paper.

    http://www.glaciers.pdx.edu/fountain/MyPapers/NylenEtAl2004.pdf

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