Sea Ice News #35 – Less ice, more snow

This is NSIDC’s report, and since I’m on a road trip, I’m unable to do an in-depth analysis. However, the WUWT Sea Ice page has more, and you can draw your own conclusions from the data presented there. Here’s one contributing factor, just have a look at 2 meter surface temperature, courtesy Dr. Ryan Maue:

Courtesy Ryan Maue, FSU – click to enlarge 

Either global warming acts in blob fashion, or that’s what we call weather. Just remember, when NSIDC says “record low” it is for a 30 year satellite data set, not for the century, or millenium, or longer. Look for pronouncements from Dr. Mark “death spiral” Serreze and from others in the media soon. As a counterpoint to such pronouncements, I suggest reading this post from Willis on sea ice recover mechanisms that seems to be overlooked by the media.- Anthony

From NSIDC: February Arctic ice extent ties 2005 for record low; extensive snow cover persists

Arctic sea ice extent for February 2011 tied with February 2005 as the lowest recorded in the satellite record. Sea ice extent was particularly low in the Labrador Sea and Gulf of St. Lawrence. In contrast, winter snow cover remained extensive in many parts of the Northern Hemisphere.

map from space showing sea ice extent, continentsFigure 1. Arctic sea ice extent for February 2011 was 14.36 million square kilometers (5.54 million square miles). The magenta line shows the 1979 to 2000 median extent for that month. The black cross indicates the geographic North Pole. Sea Ice Index data. About the data.
—Credit: National Snow and Ice Data Center 

High-resolution image


Overview of conditions

Sea ice extent averaged over the month of February 2011 was 14.36 million square kilometers (5.54 million square miles). This was a tie with the previous record low for the month, set in 2005. February ice extent remained below normal in both the Atlantic and Pacific sectors, particularly in the Labrador Sea and the Gulf of St. Lawrence.

While ice extent has declined less in winter months than in summer, the downward winter trend is clear. The 1979 to 2000 average is 15.64 million square kilometers (6.04 million square miles). From 1979 through 2003, the February extent averaged 15.60 million square kilometers (6.02 million square miles). Every year since 2004 has had a mean February extent below 15 million square kilometers (5.79 million square miles).

graph with months on x axis and extent on y axis Figure 2. The graph above shows daily Arctic sea ice extent as of February 28, 2011, along with daily ice extents for previous low-ice-extent years in the month of February. Light blue indicates 2011, green shows 2007, purple shows 2005 (the record low for the month was in 2005), and dark gray shows the 1979 to 2000 average. The gray area around the average line shows the two standard deviation range of the data. Sea Ice Index data.
—Credit: National Snow and Ice Data Center 

High-resolution image

Conditions in context

While ice extent grew at average rates for February, the overall extent remained anomalously low. Air temperatures over most of the Arctic Ocean were between 2 and 4 degrees Celsius (4 and 7 degrees Fahrenheit) higher than normal. Over the East Greenland Sea and north towards the Pole, air temperatures were 5 to 7 degrees Celsius (9 to 13 degrees Fahrenheit) higher than normal. Colder conditions, 2 to 6 degrees Celsius (4 to 11 degrees Fahrenheit) below average persisted over western Eurasia, east-central Eurasia and some of the Canadian Arctic.

As air temperatures dropped in the eastern Canadian Arctic in February, parts of the Labrador Sea started to freeze over. However, the Gulf of St. Lawrence remained mostly free of ice. As during winter 2010, when Environment Canada reported that sea ice in the Gulf of St. Lawrence was at the lowest level on record, the lack of ice will make it difficult for harp seals to give birth to their pups on the sea ice, as they normally do in February and March.

monthly graph Figure 3. Monthly February ice extent for 1979 to 2011 shows a decline of 3.0% per decade.
—Credit: National Snow and Ice Data Center 

High-resolution image

February 2011 compared to past yearsFebruary 2011 tied February 2005 for the lowest ice extent for the month in the satellite record. Including 2011, the February trend is now at -3.0 percent per decade.

Through most of January, the Arctic Oscillation (AO) was generally in a strongly negative phase, similar to the pattern that dominated the winter of 2009 to 2010. This led to very warm temperatures over the eastern Arctic, helping to account for the low ice extents over the Labrador Sea and Gulf of Saint Lawrence. However, toward the end of January, the AO returned to a positive phase, and ice began to grow in the Labrador Sea and Gulf of St. Lawrence. For more information on current AO conditions, visit the NOAA Climate Prediction Center Web page.

figure 4: masie graph Figure 4. Ice motion charts for December 2009 and December 2010 show mean sea ice drift, with the size and direction of the arrows indicating average speed and direction of ice motion. December 2010 saw stronger anticyclonic (clockwise) motion that transported ice towards the southern Beaufort and Chukchi seas.
—Credit: NSIDC courtesy James Maslanik and Chuck Fowler, CU Boulder

High-resolution image

Ice motion

Typically during a negative AO phase, weather patterns favor the retention of thick ice in the central Arctic and Canada basin, where it can better survive the summer. The negative AO also typically leads to a stronger Beaufort Gyre, which helps move ice from the western to eastern Arctic. There the ice thickens, ridging and rafting against the Siberian coast.

Last winter, the AO was in its most negative phase since at least 1951. However, slight differences from the typical AO pattern in the location of the sea level pressure anomalies had a significant impact on how the ice moved within and out of the Arctic Basin. During winter 2009 to 2010 the peak pressure anomalies were shifted towards the Barents and Kara seas, which helped transport ice from the Canadian Arctic towards the southern Beaufort and Chukchi seas. Since some of the oldest and thickest ice in the Arctic is found north of the Canadian Archipelago, this atmospheric pattern ended up further depleting the Arctic of its store of old, thick ice as that old ice melted during summer in these southerly locations.

This winter also saw a relatively strong negative AO index during December and January.  However, as we discussed in our January 5, 2011 post, the positive sea level pressure anomalies were centered near Iceland. This led to a more extensive anticyclonic (clockwise) transport pattern than last winter.  This may help keep a more extensive distribution of multiyear ice cover as summer approaches.

figure 5: snow cover extent and anomaly Figure 5. The maps of January and February 2011 snow cover data show the extent of snow cover over the Northern Hemisphere (top), and the percent difference from average snow cover extent from 1966 to 2010 (bottom). Strong positive departures can be seen over the midwestern U.S., western China, and Mongolia.
—Credit: NSIDC courtesy Dave Robinson and Thomas Estilow, Rutgers UniversityHigh-resolution image 

January and February Northern Hemisphere snow cover

Sea ice extent is only one of a number of data sets scientists use to understand how climate is changing. Rutgers University and NOAA have compiled a 45-year record of Northern Hemisphere snow cover extent from NOAA snow charts. These data show that much of northern North America, Scandinavia and northern Eurasia are snow covered between 90 and 100 percent of the time in January and February. High elevation plains and mountains at lower latitudes, such as the southern Rocky Mountains in the U.S. and Hindu Kush in Asia, also have extensive snow cover.

Over this record, in January, Northern Hemisphere snow cover averages 47 million square kilometers (18.1 million square miles), and in February it averages 46 million square kilometers (17.8 square miles)—approximately 45 to 46 percent of the land area in the region. While sea ice extent was below average for January 2011, this month had the sixth-largest snow cover extent since the record started in 1966, at 49 million square kilometers (18.9 million square miles). Snow was unusually widespread over the mid-western and eastern United States, eastern Europe, and western China. Snow cover in February remained above average at 47.4 million square kilometers (18.3 million square miles), with more snow than usual in the western and central U.S., eastern Europe, Tibet and northeastern China.

Reduced sea ice extent and extensive snow cover are not contradictory, and are both linked to a strong negative phase of the Arctic Oscillation (see our January 5, 2011 post). A strongly negative AO favors outbreaks of cold Arctic air over northern Europe and the U.S., as many people experienced first-hand these last two winters. Whether this is a trend, or in any way linked to ongoing climate warming in the Arctic, remains to be seen.

Further reading

Stroeve, J.C., J. Maslanik, M.C. Serreze, I. Rigor and W. Meier. 2010. Sea ice response to an extreme negative phase of the Arctic Oscillation during winter 2009/2010. Geophysical Research Letters, doi: 2010GL045662.

For previous analyses, please see the drop-down menu under Archives in the right navigation at the top of this page.

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77 thoughts on “Sea Ice News #35 – Less ice, more snow

  1. Which means that nothing has changed in the past 30 years…

    …and normal starts when they were predicting the coming of the next ice age

  2. why should anyone trust wuwt over actual experts at the nsidc. you guys have staked your flag on arctic sea ice “recovering” based on dubious wishful thinking. history will record you as being wrong.

  3. Notice the wording:
    “Typically during a negative AO phase, weather patterns favor the retention of thick ice in the central Arctic and Canada basin, where it can better survive the summer.”

    Rather than “….tends to be more retention of thick ice in negative AO phase, ……thick ice then lasts through summer..”… Or something to that effect.

    The subliminal suggestion here is the attribution of human emotion and a need to survive, yes, those beautiful and innocent thick ices, borne of virgin snow, gently, Mother Nature in her most precious and loving moments……B.S. We’re talking about the weather.

    This drives me nuts. There’s always the inclusion of some subliminal or even not-so-subtle pulling of heartstrings with these papers, and it detracts from the purity of the science.

    I expect this from DISNEY, not NSIDC.

    Then, we go on to say that Rutgers and NOAA have compiled a 45yr record of snow cover? 45 years?? That’s a blip in the timeline, hardly worth more than noting its value as a data set for future scrutiny in, say, 90 years.

  4. This is a key: ” This may help keep a more extensive distribution of multiyear ice cover as summer approaches…”
    During solar minimums this is what probably happened. Colder temperatures for NA and Europe while not so cold in the Artic.

  5. Why aren’t moving averages used, like for every other event, like stocks, oil, gold, etc.? Why isn’t there a 40 year, 30 year and 10 year moving average used in the reckoning, for example?

  6. Unless ice melts, it is of no use to man nor critter. One cannot eat it, nor grow on it, nor permanently live on it. It is anti-life. But when it melts, it becomes another story.

    “Towards thee I roll, thou all-destroying but unconquering ice sheet; to the last I grapple with thee; from hell’s heart I stab at thee; for hate’s sake I spit my last breath at thee.”

    Captain Ahab GK

  7. “Sea ice extent was particularly low in the Labrador Sea and Gulf of St. Lawrence. ”

    When did the Gulf of St Lawrence become part of the Arctic?

    It will no doubt be a very big surprise to residents of Quebec’ North Shore, New Brunswick & PEI that they are now part of Nunavut.

  8. Good news!! Less ice around Nfld, means less seal pups, meaning Cod stocks will increase!!! Win – Win for Nfld, lesss seals more Cod!

  9. Lets see what this year’s minimum looks like. If you look at the data, you will see little to no correlation between a year’s minimum and its maximum.

  10. What’s not to like about eliminating ice from the Arctic ocean? Better shipping, more biological activity, etc. Unfortunately, it seems the negative feedbacks result in a recovery a couple of years later. Oh, well.

  11. Golly gee ! Can that be real, if you uncover the warmer sea water, so it can evaporate some more, you actually get snow on the surrounding land; and also on the remaining sea ice.
    And as we all know, there is more land in the Arctic, than there is water, so covering the land with snow, is better for the albedo, than the sea ice is; it’s further south too, so reflects far more sunshine.

    Seems impossible to me.

  12. cthulhu says on March 3, 2011 at 8:24 am

    why should anyone trust wuwt over actual experts at the nsidc. you guys have staked your flag on arctic sea ice “recovering” based on dubious wishful thinking. history will record you as being wrong.

    Just like it records Holdren and his ilk as being wrong about the imminent ice age back in the ’70s, eh …

  13. Calling on all the precipitations experts.
    Ok, England does not get much snow or ice but it gets lots of rain. County of Oxfordshire, which is roughly in the mid-England, has detailed monthly rainfall records going back to 1853. If the rainfall is compared to the SSN no obvious correlation is perceptible, however there is an unusual 40+ year pattern. Most interesting bit about it that the periods 1920 -1960 and 1960-2000 match very closely (Rsq = 0.73). There is no correlation with the CETs or the AMO. Very odd ?!
    http://www.vukcevic.talktalk.net/ORR.htm (see graphs 2 & 3)
    Any ideas ?
    Worth looking into other globe’s regions, where the 1920- 2000 period rain records available, if the above pattern is repeated.

  14. cthulhu says:
    March 3, 2011 at 8:24 am
    why should anyone trust wuwt over actual experts at the nsidc. you guys have staked your flag on arctic sea ice “recovering” based on dubious wishful thinking. history will record you as being wrong.

    Here is a history lesson:

    http://dx.doi.org/10.1016/j.quascirev.2010.08.016

    http://adsabs.harvard.edu/abs/2007AGUFMPP11A0203F

    http://geology.geoscienceworld.org/cgi/content/abstract/21/3/227

    What happened to the positive feedback loop amplification?

    Reading Eagle – Apr 5, 1959
    “The ice mass covering the pole is slowly melting. The Arctic ice pack is 40 per cent thinner and 12 per cent small than it was at the beginning of he century. Experts predict that in not too many decades the region will melt altogether in the summer months.”

    http://tinyurl.com/6ktjjcn

    You’ll need tea and biscuits for this one.

    http://noconsensus.wordpress.com/2009/06/16/historic-variation-in-arctic-ice-tony-b/

  15. The color scheme is a bit confusing on the temp map. Can we not have white = zero anom; yellows to red, postive anom ascending; light blues to violets, negative anom, descending.

    Thanks.

  16. Note no mention of ice volume. Which anyone can see is more substantial than 2007. These people make me puke.

  17. It was about this time last year that skeptics noted a late-season “bump up” in Arctic Sea Ice extent, and were certain that it was further proof that the Arctic was recovering. Skeptics noted at the time (and correctly so) that 2008 and 2009 has shown some recovery after the record summer low of 2007. Thus, when the March-April 2010 “bump up” in Arctic sea ice occurred, we saw the likes of Rush Limbaugh crowing about how it “proved” the greenies were wrong, and that the Arctic sea ice was recovering. Some skeptics were even predicting that the summer low extent would recover all the way back to 6.0 million sq. km. Of course, those of us with a bit more understanding of the dynamics involved knew that the short-term bump up in the spring of 2010 was in no way indicative of any long-term change to the general decline of the Arctic Sea ice. A few months of growth hardly can make up for mult-year declines, and the spring 2010 “bump up” was largely very thin ice that in fact melted very quickly when the real melt season kicked in and we saw some very steep rates of decline in late spring and early summer, leading to another very low summer minimum. So what of this spring and the forecast for this summer’s extent?

    I’ll come out of the gate early as say that it looks like indications are that we’re headed for a summer low that will be very close to what we saw in 2007. Certainly, I completely reject the analysis given by Joe Bastardi that we’ll start to see some recovery to the Arctic Sea ice. Joe seems to base his idea of recovery on changes in the AMO and PDO, as these shift back their so-called cold cycle, and perhaps also the relatively quiet sun we’re having. I would not disagree that there could be some effects on Arctic Sea ice extent from these things, but what Joe et. al. seem to neglect are much more significant factors that are continuing to keep the year-to-year Arctic Sea heading ice in a downward direction. This winter, for example, especially early winter, we saw record warmth over Greenland while that cold air was pushed over Europe and other points south. These same areas saw very low sea ice. We saw a frequent Dipole Anomaly this winter, leading to the meridonal flow of air across the Arctic. This flow allowed the normally trapped cold air over the Arctic to be pushed south. Some have likened this to be “the freezer door being left open”, which is roughly accurate in terms of the effect. The net effect of this is that the Arctic has generally been above average in temps over the past several years. If we’d seen the Arctic colder than normal and the entire N. Hemipshere colder than normal than I might be pursuaded a bit more by Joe Bastardi et. al., but this hasn’t been the case.

    But beyond the effects of this winter is the longer term higher temps that have been seen across the arctic for many years, and not just air temps, but the more important warmer temperuatures of deep ocean water moving into the Arctic. This large amount of energy is not reflected in the changes in surface temps as revealed things like the PDO or AMO. Recent studies have revealed a large warming of the deeper water moving into the Arctic:

    http://www.sciencedaily.com/releases/2011/01/110127141659.htm

    But this deeper water warming is not just the Arctic, but in the Antarctic as well:

    http://climatesignals.org/2010/10/deep-ocean-waters-warming/

    Now of course, some skeptics will want to discount these kinds of studies, but the continued decline in Arctic sea ice, as well as melting of permafrost, etc. indicate continued warmth in the Arctic. This years continued low summer Arctic sea ice extent (despite whatever the PDO or AMO or solar cycle are doing) will be strong indication that the 40% rise in CO2 since the industrial revolution is playing a bigger role in the climate than these other natural variations.

  18. cthulhu says:
    March 3, 2011 at 8:24 am
    why should anyone trust wuwt over actual experts at the nsidc. you guys have staked your flag on arctic sea ice “recovering” based on dubious wishful thinking. history will record you as being wrong.
    ======
    Does this mean you won’t be making any donations for Anthony’s “road trip”:

    http://wattsupwiththat.com/2011/03/02/light-posting-this-week-and-next-but-theres-also-good-news/

    Wherein Anthony humbly says:
    “But if anyone can help with the road trip expenses for those 5 days, there’s an orange donate button on the right sidebar.”

    I figure my donations to Anthony not only help to keep him going, but also do wonders for my own sanity (such as it is), by keeping this site alive.

    You mention history.
    I ask, how will it record you?

    I would hope, that question, might get us out of this mess.

  19. How about ice thickness? that is the area that will tell the tale this summer….

    The ice thickness looks not too bad from PIPS2, but I think the tale will be one more year of death-spiral. There is a lag of a year or two between El Nino and low Arctic ice, and the 2009-10 El Nino is going to hit 2011’s summer ice. Close to 2007’s record level is on the cards, IMHO.

    Rich.

  20. “Last winter, the AO was in its most negative phase since at least 1951. However, slight differences from the typical AO pattern in the location of the sea level pressure anomalies had a significant impact on how the ice moved within and out of the Arctic Basin. During winter 2009 to 2010 the peak pressure anomalies were shifted towards the Barents and Kara seas, which helped transport ice from the Canadian Arctic towards the southern Beaufort and Chukchi seas. Since some of the oldest and thickest ice in the Arctic is found north of the Canadian Archipelago, this atmospheric pattern ended up further depleting the Arctic of its store of old, thick ice as that old ice melted during summer in these southerly locations.”

    AFAIK, no one has ever established any connection between patterns of the AO or the BG and anthropogenically generated atmospheric CO2. On the other hand quite a bit of science exists which suggests that changes in both have played a major role in the decline of Arctic Sea Ice over recent decades. They are correct that at this point “some of the oldest and thickest ice in the Arctic is found north of the Canadian Archipelago”, but prior to 1990 most all of a much larger quantity was confined to the West of the Pole by a BG circulation that covered most of the Arctic Ocean between the Pole and the Bering Strait. Rigor And Wallace 2004 revealed that a paradigm shift in the BG and the Transpolar Drift, which occurred in 89-90, lead to a dramatic decline in the amount of old thick ice in the Arctic Ocean, from 80% of the total ice to less than 30% in little over a year. These are the notes they provided for the animations the prepared to accompany their paper

    This animation of the age of sea ice shows:
    1.) A large Beaufort Gyre which covers most of the Arctic Ocean during the 1980s, and a transpolar drift stream shifted towards the Eurasian Arctic. Older, thicker sea ice (white ice) covers about 80% of the Arctic Ocean up to 1988. The date is shown in the upper left corner.
    2.) With the step to high-AO conditions in 1989, the Beaufort Gyre shrinks and is confined to the corner between Alaska and Canada. The Transpolar Drift Stream now sweeps across most of the Arctic Ocean, carrying most of the older, thicker sea ice out of the Arctic Ocean through Fram Strait (lower right). By 1990, only about 30% of the Arctic Ocean is covered by older thicker sea ice.
    3.) During the high-AO years that follow (1991 and on), this younger thinner sea ice is shown to recirculated back to the Alaskan coast where extensive open water has been observed during summer.
    The age of sea ice drifting towards the coast explains over 50% of the variance in summer sea ice extent (compared to less than 15% of the variance explained by the seasonal redistribution of sea ice, and advection of heat by summer winds).

    Here is an updated version of that animation from Dec 09

    There has been a decline in sea ice in the Arctic, but there is not much to suggest that CO2 is the major culprit behind it.

  21. Dave Wendt says:

    “There has been a decline in sea ice in the Arctic, but there is not much to suggest that CO2 is the major culprit behind it.”

    It has to be CO2. Humans don’t emit ocean currents so that will make it hard to control the global rationing of wealth, I mean energy.

    Great video.

  22. R. Gates says:
    March 3, 2011 at 12:03 pm

    This years continued low summer Arctic sea ice extent (despite whatever the PDO or AMO or solar cycle are doing) will be strong indication that the 40% rise in CO2 since the industrial revolution is playing a bigger role in the climate than these other natural variations.

    You were doing ok up until this point. Most sensible folk here know that the ‘recovery’ of arctic sea ice is a two steps forward one step back kind of progress. Ice is thicker than it was in 2007 though, so it will tolerate some warm anomalous weather. The warming of the deep ocean by co2 is a fantasy, there is no mechanism for it. However, the oceans were significantly warmed by a hyperactive sun during the C20th, and this will continue to have effects for some time yet.

  23. So let me get this straight:

    R. Gates says:
    March 3, 2011 at 12:03 pm

    Recent studies have revealed a large warming of the deeper water moving into the Arctic:

    http://www.sciencedaily.com/releases/2011/01/110127141659.htm

    But this deeper water warming is not just the Arctic, but in the Antarctic as well:

    http://climatesignals.org/2010/10/deep-ocean-waters-warming/

    but…

    This years continued low summer Arctic sea ice extent (despite whatever the PDO or AMO or solar cycle are doing) will be strong indication that the 40% rise in CO2 since the industrial revolution is playing a bigger role in the climate than these other natural variations.

    And the mechanism by which CO2 is moving warm water into the poles is what now?

    So in the Arctic, we have organisms, that are of course only sensitive to temperature, (there simply couldn’t be a single other variable which might cause their populations to increase or decrease), showing us a definitive change in temperature of 3.5°F. Wow, those are some super sensitive organism. This increase in temperature is of course due to a decrease in sea ice. But then in the Antarctic, where the anomaly has been increasing over the satellite record, we have a deep water warming trend of a whopping 0.03°C per decade.

    Amazing how both more and less ice both cause warming. Reminds me of the flood-droughts and cold-heat waves that CO2 also causes

  24. Dave Wendt says:
    March 3, 2011 at 12:31 pm
    AFAIK, no one has ever established any connection between patterns of the AO or the BG and anthropogenically generated atmospheric CO2.

    Exactly Dave. R Gates takes any decadal pattern of weather and grafts his belief system to it.

  25. R. Gates says:
    March 3, 2011 at 12:03 pm

    “We saw a frequent Dipole Anomaly this winter, leading to the meridonal flow of air across the Arctic. This flow allowed the normally trapped cold air over the Arctic to be pushed south. Some have likened this to be “the freezer door being left open”, which is roughly accurate in terms of the effect. The net effect of this is that the Arctic has generally been above average in temps over the past several years.”
    =========
    I may be mistaken, but I believe last year your theory was that the ice was being melted by the warm arctic water. And that the cold air present at the time was not having much of an effect. Shall I search the archives ?

  26. R Gates
    It took 30 years for the Arctic to get to this stage, do you expect it to regain all its loses in a couple of years.Joe Bastardi stated that over the next 20-30 years the ice would regain, not in a few years.
    Perhaps the Dipole Anomaly will disappear with the PDO entering its cold phase.

  27. AleaJactaEst says: March 3, 2011 at 11:31 am
    Can you also overlay the CET…

    Hi
    A bit of correlation with the CET’s winters, particularly 1870 – 1910; more puzzling is that the 1870 – 1910 period’s winter temperature resambles strongly to the rainfall of 40 and 80 years later, 3 peaks on way down and 2 on way up (solid blue line) see graph 4 in:

    http://www.vukcevic.talktalk.net/ORR.htm

  28. Dr. Mark “death spiral” Serreze seems to have already rejected his ‘tipping point’ idea in a news article in this weeks Nature magazine

  29. Why are we concerned about a trend in a graph that starts in 1979 and which the average is based on just 21 years of data? The Arctic has been there for over millions of years.

    In addition, when they started tracking Arctic ice area, it was just about at the same time as when the Pacific Decadal Oscillation switched from the cold period to the warm period.

    http://climate.gi.alaska.edu/ClimTrends/Change/TempChange.html

  30. u.k.(us) says:
    March 3, 2011 at 1:49 pm
    R. Gates says:
    March 3, 2011 at 12:03 pm

    “We saw a frequent Dipole Anomaly this winter, leading to the meridonal flow of air across the Arctic. This flow allowed the normally trapped cold air over the Arctic to be pushed south. Some have likened this to be “the freezer door being left open”, which is roughly accurate in terms of the effect. The net effect of this is that the Arctic has generally been above average in temps over the past several years.”
    =========
    I may be mistaken, but I believe last year your theory was that the ice was being melted by the warm arctic water. And that the cold air present at the time was not having much of an effect. Shall I search the archives ?
    ——-
    No need to search anything. There are several different processes going on covering several different seasons. During the late summer melt season, when insolation is starting to rapidly decrease once more, (i.e. mid-August into mid-September) the melting of the ice largly comes from the heat remaining in the water. This is why the amount of open water in specific areas of the Arctic earlier in the season is one of the best predictors for how the late season melt will go– that open water is warming more and will cause more melting of ice late in the summer. During the the winter months, it is not the temperature of the water that will dictate how much the ice will expand but air temperatures, as the thermal gradient between the air and sea temperatures will determine how quickly that heat can escape from the water. For example, near Greenland earlier this winter we were seeing air temperatures 20 to 30 degrees above normal. It is very hard for the water to release heat and begin to freeze over as fast when the air temperatures are so high, and in fact, it was these areas around Greenland that saw the lowest amount of sea ice and accounted for a great deal of the anomaly.

    But the bottom line is, there is simply more heat in and around the Arctic than there has been in quite some time, both air temps and ocean temps. GCM’s show that this is exactly what happens when CO2 increases, and this heat will cause the decline in seasonal sea-ice extent as well as of course, the melting of permafrost, and perhaps the additional release of methane from various warming sources underground and under the sea bed.

  31. “you guys have staked your flag on arctic sea ice “recovering” […] history will record you as being wrong.”

    cthulhu’s prediction is in. Who knows cthulhu, you could be the one… or not.
    Glad to have you jump right in there for the 2011 sea ice games! ☺

  32. mycroft says:
    March 3, 2011 at 1:51 pm
    R Gates
    It took 30 years for the Arctic to get to this stage, do you expect it to regain all its loses in a couple of years.Joe Bastardi stated that over the next 20-30 years the ice would regain, not in a few years.
    Perhaps the Dipole Anomaly will disappear with the PDO entering its cold phase.
    ______
    Perhaps…but the PDO has been going into its cold phase for several years, during which time the Dipole Anomaly has been increasing in frequency– so your supposition doesn’t seem to be holding true.

    As I stated last year, I do in fact believe that there is some influence on Arctic Sea ice from some natural cycles– from ocean to solar, but that the 40% increase in CO2 since the 1700’s is now providing a stronger influence overall. Especially interesting is the warming of the deeper waters near the Arctic and Greenland– with the deeper waters near Greenland at their warmest in 2000 years. It would seem that this certainly can’t be explained by ocean cycles alone, but perhaps some longer solar cycle is the culprit. A longer solar cycle, something in the neighborhood of 1500 years, perhaps related to the Bond cycles, is the source of my skepticism about AGW. But if I had to place money on a bet of Solar/Ocean vs. CO2 for the modern decline in Arctic Sea ice, I certainly put it on the 40% increase in CO2 since the 1700’s.

  33. A question for those who know about this sort of thing. Would satellite’s read a higher temperature anomaly if they were measuring through a snow fall? Energy, after all, is released during any form or precipitatioin isn’t it? Just wondering.

  34. I have come to the conclusion that I fail to realize the rationale behind totting the ice extent in and around the north pole.

    We have a flat trend between circa 2004 and circa 2010. Some might say seeing that way is utter BS for it is only seven years. Might be right, however, it is almost a third of the time span used for the average so it is almost a thousand years for an average calculated over three thousand years, so it’s proportionally at the least. Further we a their downwards trend during a time frame that includes the last upwards trend in temperatures from the sixties to about 1998. What would the average ice extent be if the cold of the sixties were included I wonder.

    We also have 20-30 year periodic documented history of record ice melt in the north pole and the prospect of a future of no ice during summer since circa 1880 at least.

    So essentially noting that there is, at times, less ice in and around the north pole, going from below average temperatures to above average temperatures is as concluding as noting that the same thing has happened before, several times no less, during the last 150 years, and worrying over that is about as intelligent as worrying over that the ice is fast disappearing compared to the ice extent during the recent, which we apparently ain’t free from yet, ice age.

    And since I’m such a terrible person for liking to point out the obvious what do you think would the average ice extent really be taking into consideration the optimum ice extent during the last ice age? (If it is ok to mix and match and splice proxy temperature data why not mix and match proxy data of ice extent, and thickness as well to get a proper average in this department too?)

  35. crosspatch writes,
    “If you look at the data, you will see little to no correlation between a year’s minimum and its maximum.”

    If you look at the data, there *is* a significant correlation, almost .7, between March and September Arctic sea ice extent. And both March and September ice correlate even more strongly with Northern Hemisphere temperature: warmer air, less ice. Not that the air alone is melting the ice, but both show the changing climate.

  36. If Joe Bastardi was still public he’d sing:

    “What do seals have to do with it?”

    (To the tune of Tina Turner singing, “What’s love got to do with it.”)

    The answer is that seal pups are adorable little creatures. Tremendous outrage was felt when people heard that these cute, cuddly critters were harvested for coats. The people wearing such coats all blushed scarlet, and hid their coats, or else they were doused by buckets of scarlet paint, as they walked into a theatre, by an incensed Animal Rights activist. So a very small bit of Canadian Economy was hurt, by a Save-the-Seals movement. (Small unless you happen to live in the arctic, where seals are a very big part of avoiding starvation,) (unless you depend on welfare.)

    Seals survived, to eat codfish. Codfish are not cute. No one ever saw a picture of a codfish face and had the strong urge to cuddle the cute, little creature. (Or, well, maybe someone did, but they were a bit weird, by modern standards.)

    Codfish are a far more major part of Canadian economy. Furthermore, eating fish is more common than eating seal blubber. Codfish do much more good than seals. For one thing, they help us avoid famine. So why on earth does no person say, “Save the Codfish?”

    It is due to a evolutionary phenomenon Darwin failed to notice: “Survival of the cutest.”

    It is for this reason the NSIDC’s report mentions seals. They think that, ever since women got the vote, mentioning cute creatures will help them survive. However they fail to understand how women behave when an economy gets bad. (Kipling understood, when he stated “There is no fury like the fury of a woman scorned.”)

    When a woman sees her own children hungry, and understands there are no codfish because cute seals have eaten them, “Save the seals” will be replaced by “kill the bastards!”

    We will know the economy is really going bad, if the next NSIDC report mentions codfish, but doesn’t mention seals.

  37. What would be truly climate-changy stuff would be if the Arctic DIDN’T warm in response to the warmed left-over El Nino and NAO water circulating into the bowl.

  38. I have projected the linear trend backwards in time to a pre-industrial time of about the mid 1700’s and come up with an sea ice extend for February of about 30 million square kilometers. Since there were no satelites around at that time, is there any way to confirm this extent of sea ice at that time?

  39. Ok, I am confused. I recall reading Sea Ice threads and seeing many comments such as the following:

    Then we’ve got less volume to start the melt season then we had last year at this time, (meaning thinner ice arctic wide), and since melt is really an issue more to do with volume than extent, we should have a very healthy melt. The point you raised on another post about the lack of “multi-year ice” getting flushed out this winter because of the negative AO index was true, until about the middle of March, when we saw a big uptick in ice flushing through the Fram Strait, as can be seen in this photo:

    and more particularly one such as this:

    Volume is ultimately what determines melting. Thin ice melts fast (as we saw when all the new March “bump up” ice melt away and return the Bering Sea to normal. But the warm winter (in the Arctic) really did have an impact on how thick the ice could get, and as the chart above shows, the volume of sea ice in the Arctic continues to show a very negative anomaly.

    Which between this and numerous other comments on Sea Ice pages seem to suggest that despite the slight recover of area the sea ice had after 2007 what we should really be looking at is sea ice volume.

    Accordingly, I was curious, as was others about the Sea Ice volume.

    Between Jaxa:

    and

    PIPS: (Thanks Dan)

    03.03.2011

    http://www7320.nrlssc.navy.mil/pips2/archive/retrievepic.html?filetype=Thickness&year=2011&month=3&day=3

    03.03.2008

    http://www7320.nrlssc.navy.mil/pips2/archive/retrievepic.html?filetype=Thickness&year=2008&month=3&day=3

    The Arctic Ice seems to be gaining thickness. Assuming the first quotes are correct I assume that means there is still not much to see here?

    Then again I have a feeling that now the 2 measurements have flipped positions, I am going to be told (with a very scientific meme) that now the volume doesn’t matter so much as the extent.

    At the end of the day, the record of Sea Ice extent and volume are so incredibly short that I still fail to see the point of trying to atribute any changes in Sea Ice with Human Activity when that connection is at times bizzare and apparently changes to suit the whim of the person who is doing the reporting.

  40. Looking at the IARC-JAXA extent data, only 2006 had a lower extent at this time of year. It went on to record a summer minimum of 5.8 million sq km.

  41. First the ocean cools near the equator, then it takes up to 18 years to spread up to the N. Pole. I don’t know what happens in the Atlantic, but something similar is likely at work. At any rate, the ocean has taken a decade plus a bit to cool from the 1998 peak, and the last vestage of the “hot ends” of the 60 year cycle are burning out in the Arctic Ocean.

    After this comes 30 years of building ice, just like last time (when it was open at the pole during the 1950’s and ’60s and subs surfaced there… we have photos and personal testimonials…) when the open water froze over during the New Ice Age scare.

  42. J. Bastardi forecast a 5.5×10^6km2 summer minima for 2011 I seem to recall, so it will be interesting to see if that is close. I tend to agree with R.Gates though and it will be much lower.

    I also expect, given average weather , quick melt in Hudson Bay and that quadrant.

    Is it me or is ice on the pacific side already weakening?

    Andy

  43. Pamela Gray says:
    March 3, 2011 at 7:11 pm
    What would be truly climate-changy stuff would be if the Arctic DIDN’T warm in response to the warmed left-over El Nino and NAO water circulating into the bowl.

    That would be frightening. It would mean that the oceans are getting exhausted of their heat stores.
    The last place you want to pump your warm air from your heater is outside the house, the house being the inhabitable latitudes.
    I dare say the public has had enough of the Global Warming causes Global Cooling bilge to last it a lifetime.
    Besides, Arctic Sea Ice doesn’t butter our toast, and next thing you know, they’ll be claiming that anthropogenic food comsumption causes global something.

  44. rbateman says:
    March 4, 2011 at 4:52 am

    “Besides, Arctic Sea Ice doesn’t butter our toast, and next thing you know, they’ll be claiming that anthropogenic food comsumption causes global something.”

    ___
    Actually, we don’t know whether or not the presence of Arctic Sea ice does or doesn’t butter our toast. We don’t have enough data. Ever since humans have been making butter, we’ve had sea ice in the Arctic, so there is no way of knowing how the lack of sea ice in that region might affect the ability of humans to produce butter…or toast for that matter.

  45. R. Gates says:
    March 4, 2011 at 6:26 am
    rbateman says:
    March 4, 2011 at 4:52 am

    “Besides, Arctic Sea Ice doesn’t butter our toast, and next thing you know, they’ll be claiming that anthropogenic food comsumption causes global something.”

    ___
    Actually, we don’t know whether or not the presence of Arctic Sea ice does or doesn’t butter our toast. We don’t have enough data. Ever since humans have been making butter, we’ve had sea ice in the Arctic, so there is no way of knowing how the lack of sea ice in that region might affect the ability of humans to produce butter…or toast for that matter.

    Now I know you were being facetious here, however rbateman’s claim was that “Arctic Sea Ice doesn’t butter our toast”

    now we know that toast has in fact been buttered.

    however, there is no documented occurrence of Arctic Sea Ice actively buttering a person’s toast for them.

    I think it is therefore a reasonable conclusion to reach that Arctic Sea Ice does not in fact butter our toast. There must therefore be other mechanisms by which our toast becomes buttered.

  46. @Gary Mount

    Tamino (Grant Foster) from the Open Mind blog, fitted recent sea ice extents in September by a polynomial. Extrapolating this backwards in time, this correctly showed a decrease in September extent before the 1940s.

    Arctic ice extent appears to oscillate with a PDO/AMO like frequency.

  47. kenboldt says:
    March 4, 2011 at 7:28 am
    R. Gates says:
    March 4, 2011 at 6:26 am
    rbateman says:
    March 4, 2011 at 4:52 am

    “Besides, Arctic Sea Ice doesn’t butter our toast, and next thing you know, they’ll be claiming that anthropogenic food comsumption causes global something.”

    ___
    Actually, we don’t know whether or not the presence of Arctic Sea ice does or doesn’t butter our toast. We don’t have enough data. Ever since humans have been making butter, we’ve had sea ice in the Arctic, so there is no way of knowing how the lack of sea ice in that region might affect the ability of humans to produce butter…or toast for that matter.

    Now I know you were being facetious here, however rbateman’s claim was that “Arctic Sea Ice doesn’t butter our toast”

    now we know that toast has in fact been buttered.

    however, there is no documented occurrence of Arctic Sea Ice actively buttering a person’s toast for them.

    I think it is therefore a reasonable conclusion to reach that Arctic Sea Ice does not in fact butter our toast. There must therefore be other mechanisms by which our toast becomes buttered.

    ____
    Well, yes, there was a bit of sarcasm, but truly, the shinning sun also butters your toast, for without that wonderful energy source, you’d have no butter, toast, nor energy to butter with at any rate. The interconnectedness of all things was my point, and so, how the presence of lack thereof of sea ice might in fact impact the general existence of both butter, toast, and humans to do the buttering would be the larger point.

    phlogiston says:
    March 4, 2011 at 9:12 am
    @Gary Mount

    Tamino (Grant Foster) from the Open Mind blog, fitted recent sea ice extents in September by a polynomial. Extrapolating this backwards in time, this correctly showed a decrease in September extent before the 1940s.

    Arctic ice extent appears to oscillate with a PDO/AMO like frequency.

  48. I loved the “Survival of the cutest” post. Having lived in Santa Cruz, CA for 50 years now, I can tell you that;

    a) The ‘protected’ Sea Lion population explosion of the past few decades has completely decimated local fish populations in close in coastal areas of Monterey Bay, and

    b) I’d much rather eat Salmon than Seals, and

    c) One of the places I fished as a kid, the Santa Cruz Municipal wharf, yielded thousands of fish of a wide variety of species back then. Endless barred perch, Kingfish, Walleye perch, Rock cod, Flounder, Sand Dabs, Rainbow Perch, Jacksmelt, etc etc.

    Now with the exploded Sea Lion population hanging about, the poor folks fishing from the wharf get…nothing. (And I check this personally, several times a month).

    Oh yes, for the resident NumNut who believes that the “Pinapple Express” is creating all the rain this year. Balderdash. (That’s an ancient fossil term, for you Gen X,Y,Z crowd).

    Our storms and the excessive rain from them have been the classic Gulf of Alaska origin pattern, with very heavy winds and COLDER than normal temps..and have missed the ‘warm spot’ in the Pacific altogether. These cold North Pacific storms have dumped higher than normal rainfall on the CA coast, and much higher than normal snowfall at LOWER ELEVATIONS than normal in The Sierras. 150% of normal in many places.

    Oh incidentally, our sea level here hasn’t budged in DECADES either.

    It’s so very inconvenient to the ‘story’ when actual data and observations don’t fit the alarmist computer model predictions. One must quickly flee from “AGW will cause snow to cease altogether, children won’t know what it is”…to “AGW will create a lot more snow”, in a hurry eh?

    Hmm, how did that prediction about horrible Hurricane seasons coming every year work out again???

    But then, what do I know. I’m just a lowly rocket science engineer. Maybe someday I can become a “D” science student like AlGore and create some hockey stick graphs.

    Surely we should all go back to cave dwelling, enact massive carbon taxes tomorrow, send all our jobs to emerging market economies who will pollute approx 3X what we do in the West to make the products.

    This should solve our ‘warming’ problems immediately. Well, time to break out the firewood for this weekend storm. Brrrr!

  49. What I’m seeing so far is a chance we break thru the 2007 summer low somewhat on the low side, to around 2008 on the high side. I don’t see anything that gives any indication of recovery from 2010 levels back towards 2009 or higher.

  50. r.bates said something about rbatemen and buttered toast.

    Actually now r.bateman has been mentioned I wonder if he can now comment on his thoughts over the summer that the combined extent value for both Arctic and Antarctic in December would be 21×10^6km2 ? It never did get to that value and both are low at the moment.

    The hoped for winter bounce from the sceptical side of the argument has not happened so far, unless there is a late spring like last year in the Arctic. So that is 2 summers and 1 winter favouring one side of the argument.

    Andy

  51. Andy W writes,
    “The hoped for winter bounce from the sceptical side of the argument has not happened so far, unless there is a late spring like last year in the Arctic. So that is 2 summers and 1 winter favouring one side of the argument. ”

    This spring as the Arctic melt season begins, I suspect we won’t see as many ignore-the-science predictions of “recovery” as were common last spring. Judging from comments above, this year’s predictions will more often concede that yes, Arctic ice is declining, but that’s just because of PDO/AMO/sine waves/sunspots/Atlantic water/or anything else except ACC. Recovery can still be imagined, it’s just far enough away that no evidence shows it.

    As of early March, my guess for September mean NSIDC extent is 4.6. What’s yours?

  52. geo says:
    March 5, 2011 at 7:58 am

    What I’m seeing so far is a chance we break thru the 2007 summer low somewhat on the low side, to around 2008 on the high side. I don’t see anything that gives any indication of recovery from 2010 levels back towards 2009 or higher.

    ____
    There are essentially only 2 camps on the issue of arctic sea ice:

    Camp 1: The GCM’s are generally correct and the 40% increase in CO2 since the 1700’s is now overwhelming any other natural variations and Arctic sea ice will slowly spiral down over the next few decades until we have a seasonally ice free arctic. Furthermore some models seem to show that this seasonally ice free Arctic will have profound effects on atmospheric circulation patterns (i.e. affect the N. Hemisphere weather).

    Camp 2: Nope, CO2 levels, despite being at their highest levels in at least 800,000 years have little or no affect on Arctic Sea ice, and the last few decades of decline in the Sea ice is all the result of ocean cycles such as the PDO, AMO, etc., solar cycles, or some combination thereof, and we are just at the point when arctic sea ice will begin a slow recovery as these natural cycles shift back. Folks like Joe Bastardi would be in this camp.

    Of course, the Camp 2 people were quite giddy with delight when the Arctic Sea ice appeared to make what they called a “recovery” of sorts in 2008 & 2009, and of course were quite disappointed last year when this supposed recovery did not continue on. But not to be discouraged, they quickly point out the fact that it took several decades for the sea ice to fall this far so one can’t expect it to go straight back up. Additionally, some in Camp 2 point out that the big losses for the Arctic Sea ice have all been because of the winds in the Arctic, and have nothing to do with heating, etc.

    The Camp 1 people people know that there is indeed years of ups and downs of natural variability, but it is the long term trend that really matters, and that the likelihood of there being a seasonally ice free Arctic between 2030 and 2100 is very high, and that furthermore, the likelihood that this condition is being caused by the 40% increase anthropogenic GH gases (and related positive feedbacks) is also quite high. Finally, the odds that the GCM’s would have just “happened” to have modeled the effects of increasing CO2 that just “happened” to have matched natural variability is very very low.

    Of course, I am in Camp 1, (at least 75% so, meaning I am not sitting on the fence between the two), though I stand on my tippy toes to peek over the fence and at least explore and weigh the arguments that the more educated in Camp 2 throw out. Many here in Camp 1 are “true believers” and have long since sat down by the 95-100% warmist campfire, certain in their convictions. I have no problem with that, and perhaps one day I will join them, but for now, I’ll stand near the fence and peek over occasionally. Certainly though, in the next few years, if the Arctic Sea ice continues its anticipated decline, skeptical voices such as Joe Bastardi will slowly fade away and it will be very hard for anyone to believe the AGW skeptics position, just as no one today (at least not rational people) believe that cigarette smoking does not cause cancer.

    As far as where I stand on this year’s summer sea ice minimum…it looks to be heading back close to 2007’s lows this year. The dipole anomaly and related negative AO (early in the season) has made for a generally warmer than average winter in the Arctic and the sea ice extent has been below average for the whole winter. A first projection this year puts the minimum extent somewhere around 4.2 million sq. km, but a warmer than average spring and summer in the Arctic, with a lot of early summer season melting (i.e. more early season open water) could certainly push the minimum extent down even below 4.0 million sq. km..

  53. And thus R. Gates disregards the null hypothesis, a cornerstone of the scientific method.

    During the holocene it has been up to several degrees warmer quite a few times. Did CO2 cause the ice caps to melt then, too? Gates is just making his usual argumentum ad ignorantium: “Since I can’t think of any other cause, then it must be due to CO2.”

    Scientology.

  54. Smokey says:
    March 5, 2011 at 2:12 pm

    And thus R. Gates disregards the null hypothesis, a cornerstone of the scientific method.

    During the holocene it has been up to several degrees warmer quite a few times. Did CO2 cause the ice caps to melt then, too? Gates is just making his usual argumentum ad ignorantium: “Since I can’t think of any other cause, then it must be due to CO2.”

    Scientology.
    ____

    You sit comfortably on the other side of the fence, in Camp #2, by the skeptics campfire. When the direction of sea ice is no longer a random walk, but is heading in the direction that your models indicate it would with the 40% increase in CO2 since the 1700’s, the null-hypothesis is no longer valid when applied here. Something is indeed happening outside of natural variability and the models tell us what and why.

  55. Gates says:

    “”…your models indicate it would with the 40% increase in CO2 since the 1700′s, the null-hypothesis is no longer valid when applied here. Something is indeed happening outside of natural variability and the models tell us what and why.””

    Sheesh, this guy Gates just doesn’t get it.

    What models? Models are the curse of the Warmists. They’re almost never right. Well maybe twice a day.
    Mr. Gates doesn’t remember that the 1700s were called the Little Ice Age. So its gotten warmer since then . No kidding.

  56. Rocky H writes,
    “What models? Models are the curse of the Warmists. ”

    No, most scientific interest in the Arctic centers around data, which show melting faster than predicted by the models. So researchers have been scrambling to figure out why, and where it’s all going.

    “Mr. Gates doesn’t remember that the 1700s were called the Little Ice Age. So its gotten warmer since then . No kidding.”

    Was 1980 still the Little Ice Age? It’s gotten warmer since then, no kidding.

  57. Gneiss says:
    March 5, 2011 at 3:23 pm

    Was 1980 still the Little Ice Age? It’s gotten warmer since then, no kidding.

    Tough to explain the sea ice trend when the measured change in temperature (between 1980 and now is negative …. (Granted, not very negative, but it is still still negative with UAH data being below zero.)

    Also, let’s assume somehow that a “global average air temperature” (for regions of the earth below 80 north in previous decades) did somehow affect current sea ice extents in the Arctic in winter. (When actual observation shows that sea ice melts in the summer – when measured 80 north temperatures for each summer have been declining since 1958.) So, exactly what IS the calculated change in sea ice extents for a approximated global change in temperature of only 1/4 of one degree?

    Does not this measured change in sea ice extents require a change in temperature of some 12 degrees? And does not this difference between actual real-world results and unreal-world models indicate that the models (modelers!) are dead wrong in their assumptions (er, models)?

  58. Gneiss says:

    “Was 1980 still the Little Ice Age?”

    Reading comprehension -1. The depth of the LIA was mid-1600’s – ≈1800. Estimates vary. But that was approximately the low temperature point.

    Since then the planet has been gradually emerging from the LIA. The current warming is exactly what would be expected. Therefore, the null hypothesis remains un-falsified; there is no measurable difference between natural variability and observations.

    According to the scientific method, of which the null hypothesis is an important part, you need to convincingly show that the CO2=CAGW conjecture has caused the climate to exceed its previous Holocene parameters.

  59. “Therefore, the null hypothesis remains un-falsified;”

    Smokey, it would appear that you don’t know what a null hypothesis is or how the concept is used in science. Perhaps you should describe the concept you are referring to and we can help you identify the correct terminology.

  60. Thank you R. Gates for reminding the readers of the big deal made last year on WUWT about the winter ice cover (for some reading see: http://wattsupwiththat.com/2010/03/31/arctic-sea-ice-about-to-hit-normal-what-will-the-news-say/). Back then the fact that the winter ice cover approached the 1979-2000 mean and was the latest freeze-up on during the satellite record, many readers and originators of these articles said the extensive winter ice cover meant the summer ice would recover. And as we all know, that didn’t happen.

    Now I see a lot of back peddling saying how winter ice has nothing to do with what will happen in to the summer ice in the Arctic Basin. And it is true, we cannot predict what the summer ice extent will be based on the winter ice extent. The southerly reaches of the winter ice cover are thin first-year ice that melt easily in summer. But we can say that ice growth may have been limited by warmer than normal winter temperatures (and perhaps ocean temperatures too—though I haven’t looked at the ocean buoy data). What is important is how thin the ice in the Arctic basin is and what the summer weather patterns will shape up to be. 2007-2010 were dominated by the Arctic Dipole Anomaly pattern, which in 2007 was persistent and strong the entire summer and helped lead to the large ice loss that occurred that year. But it has been present every summer since then, contributing to continued anomalously low ice years.

  61. Gneiss says:
    March 5, 2011 at 10:15 am

    As of early March, my guess for September mean NSIDC extent is 4.6. What’s yours?

    I did say last year that it would be 4.75. I think it would be around last years and plumped for a little lower. Certainly I don’t think a recovery like Jo B. was saying.

    Julienne, flavour of the month springs to mind, hence why the Antarctic is not mentioned anymore! Until it favours being mentioned ;-)

    I wonder what the ice rate melt will be when Spring starts? It was slow last year due to the weather, the ice around the edges should be thinner this year as it has been put on late, so I predict, given average weather a quick drop before hitting the normal rate later.

    Andy

  62. Does anyone know if Cryosat-2 data will become available before the dreaded PIPS vs. PIOMAS debate begins again?

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