More on the Arctic

By Michael Mann & Phil Jones (guest)

Svalbard, an Arctic island in the Northern North Atlantic, is predicted to warm considerably more than most of the rest of the earth in many model-based scenarios. See for example the figure to the right, which represents a relatively high-end IPCC Third Assessment Report scenario for the projected surface temperature difference between the period 2071 -2100 and 1961-1990. Svalbard is the island north of Norway at about 80N between 15-30E.

The enhanced warming in this region is related to the issue of polar amplification that we have discussed previously on RC. It also happens that the Svalbard meteorological station is the 2nd station in the World Meteorological Organization (WMO) meteorological station list. This means that it tends to get noticed. The Climatic Research Unit (CRU) of the University of East Anglia maintains one prominent version of the global surface temperature data set and as part of its routine quality control, CRU flags any unusual (anomalous warm or cold) new measurements that come in. Svalbard has now been flagged consistently over the past several months, but the values have been confirmed as accurate by the Norwegian Met Service, which operates the Svalbard station.

Here are the recent Svalbard monthly surface temperature measurements, the long-term (1961-1990) means (“ybar”) and standard deviations (“sd”), and associated anomalies i.e., departure from average (“delta”) for Dec 2005 through April 2006 (all in degrees C):

Month Value ybar sd Delta

Dec 05 -3.8 -13.3 4.4 +9.5

Jan 06 -2.7 -15.3 4.7 +12.6

Feb 06 -9.8 -16.3 3.7 +6.5

Mar 06 -13.1 -15.8 3.7 +2.7

Apr 06 0.0 -12.4 2.7 +12.4

The numbers are fairly remarkable. April’06 was warmer than any previously recorded May, and January ’06 was warmer than any previously recorded April. The previously warmest April was -7.0C (1996) -4.3C (2004). There is currently an absence of sea ice off much of the coast of Svalbard, which is also unprecedented for so early in the year.

The April mean temperature is almost 5 standard deviations above the mean, a “5 sigma event” in statistical parlance. Under the assumption of stationary ‘normal’ statistics, such an event is considered astronomically improbable (< 1 in 106), and, like the summer heat wave in Europe in 2003 (which was a 5 sigma event in Switzerland, 3 sigma over Europe as a whole), deserves special attention. As we have nonetheless remarked before on RC, particular events, even seasonally-persistent anomalies as unusual as these, do not “prove” anthropogenic warming. But in a statistical sense, large outliers like this make it more probable that the underlying distributions are shifting and give us a glimpse into the types of anomalies we might expect to become more common in the decades ahead.

Correction and update: (1 June) Micheal Shouler points out that we misread the previous April record (corrected above). And now that the May 06 data has come in at a record-breaking +0.9 C, our statement that April 06 was warmer than all previously recorded Mays is still true – but only just! Things move fast in this field…

88 comments on this post.
  1. Adam:

    Quick point, the link “absence of sea ice” gives “404 not found”.

    [Response: Thanks for pointing this out. Apparently that file was moved. I've replaced with an alternative image at the same site. - mike]

  2. Hank Roberts:

    That link works for me. Note the target is a .pdf file.

  3. tom brogle:

    How is the Antarctic sea ice behaving ? Is it also showing Polar Ampification?

    [Response: See our previous article "Thank you..." for a link to an extended discussion of Antarctic trennds. - mike]

  4. stephan harrison:

    Is this pattern linked in some way to the very cold winter that central and eastern Europe experienced this winter?

    [Response: This pattern appears far more persistent, as it continues well into the present season. In part, this may relate to the longer timescale of response of certain components such as sea ice to warm atmospheric conditions (such as were found for Svalbard this winter). - mike]

  5. Karen Street:

    Mike, please explain again your answer to question 4. I too am interested in the answer.

    [Response: This is an example of a more general phenomenon. The climate system represents an interaction between components that respond on fairly fast timescales (e.g. the atmosphere) and components that respond on longer timescales (e.g. the oceans, ice sheets, and to some extent the vegetation and land surface). Sea ice falls into a middle category, but it is certainly a slower response component than the atmosphere. This means that if the atmosphere tends to lock into a particular pattern in a given winter leading to e.g. a colder central europe but a relatively warm North America and a warm Eurasian arctic such as was observed this winter, then the oceans and the sea ice, both may show the effects of this atmospheric pattern well into the spring and summer, even if the atmospheric pattern itself broke down by the end of the winter. So the warm temperatures this winter over much of North America and much of the Euroasian Arctic are relevant to understanding why sea surface temperatures over the Gulf of Mexico are unusually warm this spring, and why there is so little sea ice bordering Svalbard right now. - mike]

  6. Terry Haran:

    I think you meant to say that “The *January* mean temperature is almost 5 standard deviations above the mean…”, not April. It’s also worth noting that apparently the variability in March mean temperatures must be much lower than the variablility in April mean temperatures since a March delta of only +2.7 produced an sd of 3.7, while an April delta of +12.4 produced an sd of only 2.7.

  7. Alex R:

    Is there any simple explanation for why models show so much more warming in the northern hemisphere than in the southern?

    (This, of course, has policy consequences as well, considering that the vast majority of the world’s highly developed economies are in the northern hemisphere…)

    [Response: Largely that oceans warm slower than land, and there is more land in the NH - William]

  8. Alastair McDonald:

    At the end of 1999 it was reported that the Arctic sea ice had thinned by 40% during the years preceding 1997 [DA Rothrock, Y. Yu, and GA Maykut, "Thinning of the Arctic Sea-Ice Cover" (Geophysical Research Letters, vol. 26, no. 23, December 1, 1999)]. http://www.agu.org/pubs/sample_articles/cr/2001JC001208/2001JC001208.pdf
    Since then I have been monitoring the Arctic sea ice on my web pages at http://www.abmcdonald.freeserve.co.uk/north.htm. The maps there are produced by Robert Grumbine of NOAA, and they are not altered by me in any way. They show that the lack of sea ice around Svalbard has been happening for over four weeks, but it also shows that the extent of sea ice in the whole of Barents Sea is unusually low. Moreover, the three maps for the same day of the year, today, three years ago and six years ago show that the concentration of the ice has steadily decreased. That indicates to me that the thinning of the ice has continued, and if another 40% has melted in the last ten years it may have reached a state where it is no longer sustainable.

    This early collapse of the Arctic sea ice has not been predicted by the computer models, and it seems obvious to me that therefore the models must be wrong. I very much doubt that they are correctly calculating the effect that will occur when the sea ice suddenly disappears and the planetary albedo is permanently altered.

  9. tom brogle:

    Of course the fact that much of Europe has had a colder winter is no evidence that GW is slowing. The fact that a small part of the arctic is warmer than it ought to be, is conclusive of the opposite.

    [Response: See response to comment #5 above. Parts of Europe were cold, but much of North American and the Arctic were anomalously warm. While the European winter cold was not a statistical outlier, the Svalbard temperatures were indeed a statistical outlier, as shown above. - mike]

  10. Terry Haran:

    Ooops! Please disregard my previous comment. Obviously sd is the variability in degrees C, so the number of standard deviations that the delta value represents is delta / sd; hence April is about 12.4 / 2.7 =~ 4.6 or almost 5 standard deviations above the mean, and March has a somewhat higher variablility than April (3.7 vs. 2.7). Sorry for the confusion on my part.

  11. Steve Latham:

    I believe that a warming skeptic would argue against presenting the mean and variance for the area 1960-1990 as being ‘average’ or ‘normal’ and therefore a good basis for comparison.

    [Response: The anomalies reported are dramatic record breakers for the entire record back to 1911. The reference period was only used to define a representative mean and variance (neither of which are all that sensitive to which period is used to define the long-term statistics). It doesn't influence the conclusion that the e.g. January was warmer than any previous April. - mike]

    We already know the Earth has warmed since 1975, so it shouldn’t be very surprising that some places have warmed a lot.

    [Response: You've sort of missed the point here. What you are stating, in different language, is what is implicit here. That the 'null hypothesis' of no warming looks increasingly less tenable. i.e., that events such as this reinforce the evidence that the statistics are changing in a direction consistent with what is predicted by anthropogenic climate change. - mike]

    Next, a skeptic might make point #9 that a focus on one place is unwarranted. My lack of Bayesian training/understanding leaves me by default a frequentist, and the frequentist inside me cries out for some kind of Bonferroni correction or Fisher’s method of combining probabilities over time and/or area to evaluate the result in context. Of course, neither approach is appropriate because results aren’t independent in time or space.

    [Response:Your two statements above are not really consistent. On the one hand you're arguing that this isn't representative because it only looks at one station (as we point out, there are good a priori reasons to look at this particular station) and yet on the other hand, that the trend here is likely indicative of larger-scale trends because of spatial correlation. The latter statement is true, and, of course, it is implicit in why we look at Svalbard, which is one of the few long-term available meteorological stations which fall within the broad region where models predict the greatest warming (e.g. as indicated by the A2 scenario simulations results shown) - mike]

    But there is something to be said for putting the result in context! Perhaps a more complete post would include evaluation of what happened at Svalbard in other recent years

    [Response: If you look at the table, its clear that what has happened in this year is remarkably different from what has happened in any past year (the record goes back to 1911), including recent years. - mike]

    , or, since the main point seems to be about variance in sensitivities among places, a comparison to results at other places would be in order (e.g. somewhere with a WMO station that models suggest will not warm very much). Sorry for whining — I’ll check the links to see if I can find the context.

  12. Caspar Henderson:

    In May 2003, a group of us with CapeFarewell saw a polar bear swimming offshore at Bear Island, some distance S of Svalbard. The captain and his crew said this was a freakishly rare event these days. See here

    A trivial and thoroughly unscientific anecdote; but at an intuitive level it struck home.

  13. pete best:

    Here in the UK the cool recent winter was explained by the North Atlantic Oscillation being weaker between the front in the Azores and the front off Iceland. Is there any evidence of the NAO being effected by GW?

    [Response: The NAO is predicted to tend increasingly towards the positive phase in some simulations of the response of the atmospheric circulation to anthropogenic forcing. See e.g. this Nature article by Shindell et al (1999). - mike]

  14. Dan Hughes:

    The figure shown in the introduction for this thread are calculated results for the period 2071 – 2100 using the IPCC TAR A2 scenario.

    What are the calculated results for December 2005 – April 2006 using the historical record as the scenario?

  15. Chip Knappenberger:

    Dear RC,

    Using maps of climate model projections of patterns of warming as a priori evidence of the temperature behavior in specific locations is an acceptable practice? Can this technique only be used in the positive sense? Or, since SRES A2 doesn’t show a relatively high warming rate for the Antarctic Peninsula (relative to the rest on Antarctica), a location often referred to as having one of the greatest warming rates on the planet, does the behavior of the Peninsula serve as evidence counter to our understanding?

    Also, I am confused about comparing Switzerland and Svalbard. How do I interpret the fact that the SRES A2 projection that you showed indicates that Switzerland should only be warming at about half the rate of Svalbard and yet both places recently experienced 5 sigma events? Do the projected patterns of warming matter? Is it the warming rate that matters or the variances or both? Based on the recent events in Switzerland and Svalbard, and using the a priori information from the A2 depiction of projected climate changes that you provided, where are some other places that we should expect to see large positive temperature events? Or, perhaps more importantly, where are some places that we should NOT expect to see them?

    Thanks,

    -Chip Knappenberger
    (disclosure: I have, to some degree, been funded by the fossil fuel industry since 1992)

    [Response: You raise some good quesitons. With respect to your first point, note that this post did not make any claim that the data validate the model, or vice versa. There happens to be qualitative agreement, but Mike and Phil weren't making the claim that the observations prove that the models are accurate. The lack of warming respresented in (most) models for the Antarctic Peninsula is indeed an important issue. However, modelers are well aware that they don't get sea ice, ocean heat advection, or stratosphere-troposphere coupling right in the models in the Antarctic at the moment -- largely due to lack of resolution. All of these are implicated in the particular pattern of warming and cooling in Antarctica. It comes as no surprise, then, that we don't get the Antarctic warming right. We don't really understand it yet, in my view. Having said that, model runs I've looked at do indeed show more warming over the Peninsula that anywhere else in the Southern Hemisphere -- but they don't show as much as observed. -eric]

  16. Steve Latham:

    Hi Mike,
    Re #11, I followed the global surface temperature data set link and tried to download some temperature data (first time I’ve ever tried) and got a bunch of missing data (-9999) and a lot of zeros. I wanted to look at the table of data back to 1911, but I’m embarrassed to admit that I didn’t figure out how to do it.

    I confused myself by trying to come at this like a GW skeptic (which I am not), and it wouldn’t surprise me if I sort of missed the point. I thought you were saying that Svalbard 2006 was special. I was saying that to evaluate that special-ness, there should be more context — the number of 4 and 5 sigma events (compared to ’61-’91 means) since 1992, say, over the number of such events possible is the kind of thing I would search out for confirmation. And I was thinking in terms of “On record breaking events” by Rasmus: http://www.realclimate.org/index.php/archives/2005/08/on-record-high-temperatures/
    (which is missing the helpful graphs, btw).

    [Response:You can see an illustration for the April month here, based on met.no station data from Svalbard airport (other months do not look as spectacular...). The data is also available on-line from met.no eKlima, but this web-site is unfortunately only in Norwegian (and one needs to registrer before accessing data). -rasmus]

  17. Alastair McDonald:

    Here’s the real truth about what is happening in Svalbard. It is not an isolated incident. We have passed the tipping point in the Arctic. see:

    Meltdown fear as Arctic ice cover falls to record winter low

    David Adam, environment correspondent
    Monday May 15, 2006
    The Guardian
    http://www.guardian.co.uk/science/story/0,,1774815,00.html

  18. Steve Sadlov:

    This year, the North Pacific is colder than normal and the North Atlantic / low longitude Arctic is higher than normal. How long is the Atlantic Cycle, and I don’t ask this from sheer ignorance. I ask it due to the fact that while ENSO is comparatively well studied, the Atlantic version is less studied. For example, what if there is a 40 plus year supercycle in the Atlantic? There has been lots of debate on this, but no bullet proof conclusions.

  19. llewelly:

    Related data point: In this graph one can see that over the arctic as a whole, sea ice extent is currently lower than it was at this time last year. By a related graph one can see that this has been the case for all ~4.5 months of 2006. A similar graph for the Barents Sea is available on the same site.

    I’m wondering how arctic climatologists make seasonal forecasts of sea ice extent, and where such forecasts are announced.

  20. Steve Latham:

    Dear Chip (#15), I’m going to try a quick answer before somebody more knowledgable steps in. If you are trying to question whether model projections have more often been supported or refuted by subsequent data, you will no doubt find that the answer is the former (overwhelmingly). If you want to examine the accuracy of model outputs for specific geographic locations in 2071-2100, you’ll have to wait for average temperatures to be recorded in the future. I admit that I didn’t fully understand this post, but surely you are tilting at windmills. I think the takehome message here is that as average temperatures in time and space rise, some locales (in both time and space) are likely to reach very extreme values. What do your benefactors want you to say with regard to costs borne by those forced to endure those extremes?

  21. Gareth:

    I posted this elsewhere (in the wrong place – now the right place comes along!):
    What are the model sensitivities to Arctic sea-ice melt? We’ve recently had an interesting post on the Greenland and Antarctic ice sheets, but I can’t recall much on sea ice. Specifically, what do the current models suggest is a reasonable time frame for Arctic sea ice reduction (timing and extent), and are we “on target”? I get the sense that we’re into positive feedback here, and that there’s some surprise at how fast things are happening, but perhaps I’m only reacting to alarmist media coverage… ;-)

  22. greeny:

    “”
    How is the Antarctic sea ice behaving ? Is it also showing Polar Ampification?

    [Response: See our previous article "Thank you..." for a link to an extended discussion of Antarctic trennds. - mike]

    Comment by tom brogle â?? 22 May 2006 @ 9:51 am
    “”

    could you please add a hyperlink to the “Thank you…” article
    because I cannot find it in your archives or with a search.
    Thanks,

    [Response: I meant our most recent previous post (May 18) "Thank you for Emitting" just below this one. It has links to our previous discussions of the Antarctic. - mike]

  23. Hank Roberts:

    #20, Steve L., you’ve run together the statement in #14 (Dan Hughes) — referring to dates in the future — with the following post #15, written by Chip K.

  24. Steve Bloom:

    Re #21: The difficulty with abrupt feedbacks is that they’re a little tough to incorporate into a model before there are any observations. We saw the same problem with dynamical ice loss. There are plenty of other examples, another Arctic one being methane loss from tundra. It’s this sort of thing that makes a lot of people (including most climate scientists, I think) very nervous about even the lower-end IPCC scenarios. But regarding the sea ice, read the story linked in #17 and in particular the last paragraph. Eek, if so.

    If there were a sea ice modeler among the RC authors, perhaps we could even hope for a post on all of this. :)

  25. Dan Hughes:

    The processes that can lead to reduction in the mass of ice compared to a reference period include: (1) air temperature above the freezing temperature for longer periods of time, (2) increased water temperature for the case of floating ice, (3) increased rates of sublimation, (4) increases in the ice-air and ice-water surface area (smaller chunks of ice have more surface area than a single chunk having the same mass), (5) decreased precipitation under conditions suitable for freezing, (6) increases in the absorbed radiative flux compared to the reference period, and (7) increases in precipitation under conditions suitable for melting. There are most likely others.

    Which of these has been identified by measured data to be the dominant factor in the observed reductions in ice mass.

  26. Gareth:

    SB: “Eek, if so.”

    Quite.

  27. Nigel Williams:

    As we fear about sea level rise, what sort of loss of water do the models see from the global atmosphere to the vacuum of space? Is there actually significantly less available water (as surface water or ice) on the earth now than during past events, and if so would that lower the high-tide mark for a given temperature rise over that at previous events?

  28. Hank Roberts:

    Wow. From the Guardian article Alastair suggested in #17:
    “… Experts at the US Naval Postgraduate School in California think the situation could be even worse. They are about to publish the results of computer simulations that show the current rate of melting, combined with increased access for warmer Pacific water, could make the summertime Arctic ice-free within a decade….”

    Any submariners (US, ex-USSR, or others) reading and able to comment here?

  29. Hank Roberts:

    Here’s a place to look for more info — theses by graduates of the US Navy Postgraduate School, url for search is:
    http://www.nps.navy.mil/moves/Theses.htm

    I tried “sea ice” and: search found 63 titles.

    The first one is about computer modeling of arctic sea ice.

  30. Gareth:

    Further to “Eek”, if you put an ice-free Arctic into models with roughly today’s level of CO2 (or slightly higher, say ten years worth – what, around 400ppm?), what does that do to the rest of the world?

  31. Steve Latham:

    Hi Hank,
    No, I was writing to Chip (#15) about his questions. He was wondering about recent high temperatures in Switzerland and the Antarctic Penninsula, and whether they should undermine our confidence in model results. I was trying to point out that the model results are for average temperatures a long time into the future. Dan Hughes (#14) asked a more sophisticated question than did Chip (IMO), and I hope somebody will soon be able to provide a retrospective evaluation of near term GCM predictions at local scales. My limited understanding, though, is that precision in the model results is low and that only coarse regional predictions would be precise enough to allow meaningful comparisons to observations.

  32. Steve Bloom:

    Re #19: The National Snow and Ice Data Center at http://nsidc.org/ is a much better site for all of this, as UIUC (which is a one-person operation) has data but little explanatory material. For the Antarctic, see the British Antarctic Survey at http://www.antarctica.ac.uk/ (although the site seems to down just now). The latter is rumored to employ a part-time sea ice modeler who might be able to contribute a sea ice update post here.

  33. Steve Bloom:

    Re #28: It was the thought of this potential for cascading positive feedbacks that led to my pithy expletive. Fortunately at a certain point negative feedbacks kick in, or we’d all have to learn to speak Venusian. :)

  34. Gareth:

    Re #30: And there’s more… Reuters UK are currently reporting two papers from GRL’s next issue:

    “It means the warming is happening faster, each decade is actually warming faster than it would have,” [Margaret] Torn [Lawrence Berkeley Nat Lab] said in a telephone interview. “It’s the pace of change that will be one of the big problems. It’s how humans adapt and the cost that will depend on the rate of change of climate.”

    The problem with the negative feedbacks is that if we don’t impose them on ourselves, they may only happen long after our civilisation has gone the way of the Maya.

  35. Steve Bloom:

    Re my #33: What was #28 became #30, in case that’s not obvious.

    Re #31 (Steve L.): Just to make sure you know, Chip wasn’t wondering about any of this. He already knows the answers. Some might call it trolling…

  36. Coby:

    Steve,

    If there were a sea ice modeler among the RC authors, perhaps we could even hope for a post on all of this

    None of the good sea ice modelers have time to blog!
    :-) :-) :-) :-) :-) :-)

  37. Hank Roberts:

    At least they write!

    This may be the basis of the recent press report, though I’m guessing; the author’s conclusion is about summertime ice, not year-round ice conditions.

    http://library.nps.navy.mil/uhtbin/cgisirsi/v3pbVv5ALC/SIRSI/204100014/523/10074

    McNamara, Terry P. Determination of changes in the state of the Arctic ice pack using the NPS Pan-Arctic Coupled ice-ocean model.

    ABSTRACT
    This thesis provides an analysis of the diminishing sea ice trend in the Arctic
    Ocean by examining the NPS 1/12-degree pan-Arctic coupled ice-ocean model. While many previous studies have analyzed changes in ice extent and concentration, this research focuses on ice thickness as it gives a better indication of ice volume variability.

    The skill of the model is examined by comparing its output to sea ice thickness data gathered during the last two decades. The first dataset used is the collection of draft measurements conducted by U.S. Navy submarines between 1986 and 1999. The second is electromagnetic (EM) induction ice thickness measurements gathered using a helicopter by the Alfred Wegener Institute in April 2003. Last, model output is compared with data collected by NASA�s ICESat program using a laser altimeter mounted on a satellite of the same name.

    The NPS model indicates an accelerated thinning trend in Arctic sea ice during
    the last decade. The validation of model output with submarine, EM and ICESat data
    supports this result. This lends credence to the postulation that the Arctic not only might, but is likely to be ice-free during the summer in the near future.

  38. Hank Roberts:

    P.S. — why do we have that Navy submarine data available for research? The area first declassified is called the “Gore box” — the thesis noted above mentions it without explanation, and says subsequently a somewhat larger area was allowed declassified.

    For an explanation we can turn to, of all places, the explanation here: http://www.john-daly.com/polar/arctic.htm

    “not all the Arctic was analysed in this way. For security reasons relating to the Cold War, only the `Gore Box’ was involved, a roughly rectangular region of the central Arctic which the then Vice-President Gore moved to have de-classified for purposes of sea ice data analysis. The criteria for determining the boundaries of the `Gore Box’ is not known …”

  39. Paul Biggs:

    Most of the glaciers in Svalbard are of the ‘surge’ type. It is therefore difficult to use the front position of a single glacier as a climate indicator, because the front will shrink and retreat in periods between surges. The front position therefore gives little information on whether the ice mass is growing or shrinking. The dynamics of surging and the relationship of surging to climatic factors are poorly understood.

    I assume Professor Ole Humlum of the Norwegian research centre on Svalbard is real. He pointed out that glaciers there typically experience a rapid advance lasting 5 to 7 years, then retreat slowly for the next 80 to 100 years; an entirely natural phenomenon.

    I did a quick search a few weeks ago:

    http://www.bioone.org/perlserv/?request=get-abstract&doi=10.1657%2F1523-0430(2003)035%5B0264%3AOTNMBO%5D2.0.CO%3B2

    “The overall total net balance is slightly negative, -4.5 ± 1 km3 yr^-1, giving a specific net balance of ca. -120 ± 30 mm yr^-1 over the archipelago. The contribution of ice caps and glaciers on Svalbard to global sea-level change is, therefore, close to 0.01 mm yr^-1 as an average value over the last 30 years, which is less negative than former estimates.”

    http://pubs.usgs.gov/of/1998/of98-031/norway.htm

    http://adsabs.harvard.edu/abs/2002AGUFM.U71A..02B

    “For the largest icecap in Svalbard (Austfonna) the upper accumulation area shows a remarkable thickening, which, when converted to an ice equivalent value, represents a 36% increase in accumulation rate.”

    http://www.geophysics.helsinki.fi/glaciology/anja.htm

    “The project also aims to improve current knowledge on Svalbard polythermal glaciers: their hydrothermal properties, drainage and behaviour in the changing climate.

    About 60% of Svalbard (36 600 km2) is covered by glaciers of various types. Although this is less than 1% of the total glaciated area of earth’s land surface, globally it is an important area to study glacier behaviour because of the short response times of the glaciers to changes in climate compared to the ice-sheets of Antarctica and Greenland. Svalbard glaciers are classified as sub-polar or polythermal in respect of their thermal structure, typically containing layers of ice that are both at and below the freezing point. This means that their structure is different and more complex than the well-studied mountain glaciers in temperate regions, and therefore their response to changes in climate is also different and more complex and needs careful studying.”

  40. Peter Hearnden:

    According to GISS April 2004 had a mean of -4.3? March 1996 was -7C?

    Whatever, they’re still just amazing figures and, fwiw, I think the analysis right.

  41. Paul Biggs:

    Here’s one I missed:

    Two ice-cored 18O records from Svalbard illustrating climate and sea-ice variability over the last 400 years
    Authors: Isaksson, Elisabeth1; Kohler, Jack1; Pohjola, Veijo2; Moore, John3; Igarashi, Makoto4; Karlof, Lars1; Martma, Tanu5; Meijer, Harro6; Motoyama, Hideaki4; Vaikmae, Rein5; van de Wal, Roderik S.W.7

    Source: The Holocene, Volume 15, Number 4, May 2005, pp. 501-509(9)

    http://www.ingentaconnect.com/content/arn/hol/2005/00000015/00000004/art00003;jsessionid=wn42i7at0pet.victoria

  42. jhm:

    This must have been covered elsewhere, but what are the factors (as far as we think that we know them) that cool the planet after periods of warming? A related question: how possible is a ‘point of no return’ Venus scenario? and what do we think about the conditions that need to be met?

  43. PHEaston:

    Global warming risk “much higher” than already expected:

    http://news.bbc.co.uk/2/hi/science/nature/5006970.stm

    The research will be published in the journal Geophysical Research Letters.

    Note that “The studies challenge the consensus view of the Intergovernmental Panel on Climate Change (IPCC)”, so how much should they be taken seriously?

  44. Mauri Pelto:

    It will be interesting to see the impact of this warmth on glacier mass balance on Svalbard. Two glaciers Midre LovenBreen and Austre Broggerbreen have mass balance records since 1968 and 1967 respectively. The mean annual balance for the first 25 years of the record was -0.32 m/a and -0.4 m/a. From 1993-2004 the balance has been -0.51 m/a and -0.6 m/a respectively. Averaging the loss of a half meter of ice thickness across the entire glacier each year is not a small change. Is it even going to get worse? Fortuitously a project called SLICES is underway (Changes in Glacier Geometry and Extent in Svalbard: Implications for Sea-Level Rise during the 20th and 21st Centuries) undertaken by the University of Wales, Swansea.

  45. Paul Biggs:

    Re; http://news.bbc.co.uk/1/hi/sci/tech/5006970.stm

    Climate modeller James Annan:

    [full text replaced with link]

    http://julesandjames.blogspot.com/2006/05/ho-hum.html

    [Response: You are confusing two issues. These new papers (which we'll have a post on shortly) are not about climate sensitivity in the sense discussed by me and Annan, but about other feedbacks (specifically carbon cycle issues) that are not part of the 'climate sensitivity' question, but that are clearly relevant to what will happen in the future. This difference was explained in my last post on the subject: http://www.realclimate.org/index.php/archives/2006/03/climate-sensitivity-plus-a-change/ -gavin]

  46. Hank Roberts:

    >43
    The BBC article names the several research teams involved.

    As I understand the last round of IPCC models don’t incorporate (because they couldn’t quantify) feedbacks from soils releasing added CO2 (nor feedbacks from burps of methane, which no one has modeled yet, right?).
    .
    Models incorporating these feedbacks would necessarily challenge the 2001 IPCC conclusions, eh? Presumably the 2006 IPCC conclusions will anyhow, whether they include these particular feedbacks or not.

    The whole question of how modelers could possibly include feedbacks we know exist but can’t quantify — like CO2 from massive erosion or dieoffs of plants, or methane from clathrates burping — is a bit of a nightmare, I suspect.

  47. Hugh:

    A little supplement to #43:

    http://www.berkeley.edu/news/media/releases/2006/05/22_icecore.shtml

    which includes…

    “Both researchers emphasize that the large temperature range they predict – 1.6 to 6 degrees Celsius – does not mean that we have an equal chance of ending up with less warming as with greater warming. In other words, it doesn’t mean that the uncertainties are symmetric about an average increase of 3.8ºC.

    “People see this uncertainty and think that we have an equal probability of dodging a bullet as catching it. That is a fallacy,” Torn said.

    “By giving the appearance of symmetric feedback, people have an excuse to say, ‘Maybe we don’t have to worry so much,’” Harte said. “But while there are uncertainties in the feedbacks, all the major feedbacks are positive, meaning they would increase warming, and we know of no significant negative feedbacks that would slow warming.”

  48. wayne davidson:

    Whoaa! And I thought we warmed up (Canadian Arctic), between +3 to +6 C anomalies all winter, with the spring early by a month, and ice thinning and cracking open earlier as well. Swalbard had it much warmer. Hard to imagine, but so. The big question remains: how fast is this global warming? From a perspective of the NH Polar regions, it is hitting the North at a strong pace, agreeing with those who say that IPCC is too conservative, but the key issue of certainty will not be achieved, given complexities related to this Polar warming, it is therefore imperative to explain these related anomalies, ie Russia winter of 2005-06 without confusing some that GW is nevertheless gaining ground. For those who think that the Polar regions are small, think again, they always had a huge impact on the weather at lower latitudes.

  49. Paul Biggs:

    Re; 45

    Sorry, I was linking the 2 issues – the estimate of climate sensitivity and the added CO2 released from ecosystems. If the temperature response to CO2 is logarithmic, adding more CO2 will have diminishing effect. I also wonder if the infra-red absorption bands can become saturated?

    [Response: The logarithmic effect is already incorporated in radiative transfer models. And a "diminishing effect" does not necesessarily mean a "small effect," if that's what you're getting at. Look at it this way: we all agree that the effect of doubling CO2 will be substantial, and any feedback that accelerates CO2 release will make the day of doubling come sooner, giving ecosystems and society less time to adapt, and requiring tighter emissions targets if one is to avoid doubling. The answer to your question at the end is "no." At least not in any sense that should concern us in the least. The CO2 bands are still not completely saturated even for Venus, insofar as the effect on the top of atmosphere radiation budget goes. There are still bands that are relatively transparent to infrared and can be strongly affected by adding more CO2. In fact, the question of saturation doesn't even completely make sense as applied to greenhouse warming, because even in an optically thick atmosphere the radiation that escapes to space always comes from the high (and generally cold) tenuous part of the atmosphere, where the bands are by definition not saturated. In that sense you never reach a point where adding more CO2 stops increasing surface temperature. --raypierre]

  50. Hank Roberts:

    Gavin, may I suggest a new term — “climate reactivity” — for effects of those factors not well understood, not incorporated into models, and not currently part of climate sensitivity calculation.

    The term has analogous uses in chemistry, nuclear physics, and even psychology/psychiatry.

    It always means those factors that may not be well understood and can cause unexpected trouble.

  51. Steve Bloom:

    Re #45 response: But Gavin, note this Martin Wild quote from the BBC story: “If this additional carbon feedback is proven to be realistic, than that would raise the climate sensitivity up by a certain amount.” If you meant that this feedback hasn’t been part of past discussions about sensitivity, I think I understand, but otherwise I’m confused.

    Re #49: Note that these studies track the past behavior of this feedback and extrapolate it to the present climate, so whatever diminishment or saturation may have taken place in the past is “built in” to the calculation of future sensitivity.

  52. Steve Bloom:

    Also re #49: I should add that as far as I understand it this would be true up until the point where the current climate warms up beyond what it has been in the last 400,000 years. We have a ways to go on that. Once out of the historic range, I assume you’re right that the factors you mention would need to be taken into account, and the new studies would have needed to do so in order to come up with sensitivity estimates comparable to prior ones. But I’m way beyond my expertise in speculating about this, especially since I haven’t even seen the papers yet.

  53. Ken Rushton:

    May I draw your attention to an interesting page, which shows the Sea-surface temperatures as compiled by the US navy: https://www.fnmoc.navy.mil/products/NCODA/US058VMET-GIFwxg.NCODA.glbl_sstanomaly.gif . The interesting bit here is that it apparently shows a deeper cross-section than say NOAA’s: http://iridl.ldeo.columbia.edu/SOURCES/.NOAA/.NCEP/.EMC/.CMB/.GLOBAL/.Reyn_SmithOIv2/.weekly/
    The display (I’ve checked it occasionally for years) has been boring, because it shows very little temperature variation in most of the ocean, but recently, in the past couple of years, the temperature around the very northern part of the Atlantic, north of Iceland (and this year west of Greenland) has gone up. It’s now up +4 or 5 degrees. What does it mean? I’ll leave that to you experts, but my armchair guess is that the THC sinking spot has moved over 500 km poleward, and the diagram is showing the warmer waters drawn up form the south, which were formerly a seawater/ice mixture @ -4 degrees or so.

  54. Hank Roberts:

    Ken, very interesting! I wonder if that change is in the thesis I cited in #37, 38, I’ll look. The navy always has better info!

  55. Nigel Williams:

    All this stuff is happening about as fast as you guys can type!

    Is it the intention that govenments will only be allerted by the final edition of IPCC2006 (circa mid 2007), or are there some other mechanisms available that can produce a reasonably cohesive report to the UN et al that will ring some bells sooner?

    How is this new rate-of-change information being assimilated into the ICPP peer review process?

  56. Bill Sneed:

    Re: #44 While it is true that both Midre Lovenbreen and Austre Broggerbreen are well studied it should be mentioned that both are located in one of the warmer parts of the archipelago. The western edge of Svalbard is heavily influenced by relatively warm oceanic and atmospheric currents. Both glaciers are also quite small — about 6 sq. km and 12 sq km respectively and, thus, more likely to influenced by climate variations. Of the approximately 2,200 glacier on Svalvbard, those less than 100 sq. km account for about 47% of the number but only about 34% of the snow and ice covered area. It would seem prudent to exercise some care if one is to use these 2 small glaciers are “mine canaries”.

    Regarding sea ice in the Nordic Seas, Torgny Vinje’s 1 February 2001 paper in the Journal of Climate makes fascinating reading. No doubt things have changed — perhaps significantly — since its publication but it is a valuable perspective nonetheless.

  57. pat neuman:

    re 55.

    No bells rung on TV network news this evening (I watched ABC). There was coverage on the hurricane outlook for 2006 which was issued yesterday by the National Weather Service but there was no mention of global warming in their press release. Public broadcasts by meteorologists occasionally talk about a cool flow of air from the Arctic without acknowledging that climate change in the Arctic is being amplified as expected by global climate modelers.

  58. Dano:

    RE 50 (Roberts):

    “Emergent properties” is the term used in adaptive management and scenario analysis (as in IPCC) to describe roughly what you propose (fancy term for ‘surprise’).

    But I like your term!

    Best,

    D

  59. Hank Roberts:

    Chuckle.
    Reactivity (chemistry): … susceptibility to undergoing a … change that may result in dangerous side effects, such as … toxic emissions. The conditions that cause the reaction, such as heat, … will usually be specified as “Conditions to Avoid” when a chemical’s reactivity is discussed on a MSDS. http://www.weizmann.ac.il/safety/chgl.html

    Reactivity (fission): … a change in power caused a change in reactivity and this in turn had an effect on power. If the change in reactivity is such that the processes caused are against the originating ones, we talk about negative feedback….. In terms of reactor safety it is an obvious intention that all feedbacks should be negative…. As a counter-example … we may mention the RBMK type reactors, because in these positive feedbacks … contributed to the accident of the Chernobyl power plant.

    I’ll skip the psychological uses (grin).

    Aside — on the naval grad school study, at the back — they used monthly averages but could do daily points, the submarine and satellite data is that detailed. And the author makes a clear plea for further declassification and organizing of available data, saying he used almost everything that’s publicly available to model the current situation.

  60. wayne davidson:

    #57, Pat… The networks will get around to report what is going on……. One day…. Mean time
    there is always newsprint which seems to be way ahead on this issue, the polar regions are for writers
    what the tropics are for TV…

  61. Paul Biggs:

    Re;49

    Thanks. If I’m reading this right, the world could warm by 7.7C or more by the year 3000 – a 994 year extrapolation assuming no other factors working in the opposite direction.

  62. C. W. Magee:

    Re: 61: I think we might run out of some, if not all fossil fuels sometime in the next 994 years. At the very least, the current rate of emission increases is likely to slow before then.

  63. PHEaston:

    Re 57 Pat
    Perhaps you should move to the UK. Here, the media never misses an opportunity to link a weather event to global warming. And the BBC is starting a season on Climate Chaos from tonight (with the great David Attenborough): http://www.bbc.co.uk/sn/hottopics/climatechange/climatechaos.shtml
    It strange, however, that with northern Europe going through one of the coldest, most miserable springs for many years (and a friend of mine in Chicago says they are experiencing the same), there’s no mention of how this fits into global warming theory. (Paradixically, parts of southern England also have hose-pipe bans due to a dry winter – wasy to link to global warming). I would be the first to agree that one event or one unusual year does not make a trend, but we regularly see the media assume just that with hot weather or floods.

  64. Almuth Ernsting:

    Re 63:
    The UK and northern Europe going through a cold and miserable spring? You must exclude Scandinavia, which has been very warm. For the UK, March was the first below average month since October 2004. April has been above average, and the Central England Temperature for May is so far above average. It’s indeed a sign of global warming that what would have been warm temperatures in the past are now experienced as ‘cold’!

  65. teacher ocean:

    Re 62: I thought we had about 70-100 years of oil and about 250 years of coal left, if we continue with the current rate of consumption.

  66. Carl Christensen:

    well, PH, the zeal of some media outlets to link everything from coastal erosion to dry spells with global warming doesn’t mean it ain’t happening! ;-) and it sure beats the insipid sort of “CO2 – we call it life” from the right-wing think tanks, n’est-ce pas?

  67. James Davey:

    Current oil reserves and future use are two very different things. With oil companies already looking at oil sands, oil shales and methane hydrates as potential fuel (and money) sources, and the UK coal industry lobbying government to re-open UK coal seams (which may now, it seems, be competitive, there is a big future in fossil fuels.

    IEA World Energy Outlook data suggests global fossil fuel burning will increase by about 50% by 2030, with no signs of slowdown.

    My guess is that we reach 700ppm CO2 long before we start worrying about fossil fuels running out.

  68. Leonard Evens:

    Re #63: Spring in Chicago

    While we have had a lot of cool weather recently, my estimate is that spring arrived about a month earlier than usual. I’ve lived in the Chicago area since 1964. Our typical pattern is that it goes from winter to summer without much of a spring in between. Usually, it hopeless to start planting until late May, but things started growing in April this year. The flowering trees and shrubs have already lost their blooms. While it has been a cool spring, it started much earlier than usual and has lasted quite a while. Temperatures, with a few exceptions have been in the 50s and 60s but the latest forecast is for near 90s by the weekend.

    Our winter was also relatively mild. I’ve been able to cycle outside except for about three weeks in December, which is also unuusal. Usually, I don’t start cycling outside until March or April. I don’t like to cycle when it is much below freezing, so that means our low temperatures this year have been relatively high.

    The problem with Chicago weather is that we are on the boundary between Gulf air and Canadian air, and so we are prone to rapid changes in conditions and we sometimes have long periods of either high or low temperatures. But my general impression is that the trend in recent years has been towards earlier springs.

  69. Steve Sadlov:

    RE: #25. Also, salinity.

  70. Steve Sadlov:

    RE: #56. Many people fail to realize that ever since people have sailed into the Arctic, the effects you mentioned have tended to keep the broad swath between Iceland, the British Isles, the Greenland – Svalbard ice edge and the Eastern ice edge ice free even in winter, most years. The “Arctic Ice Cap” (a misnomer, for sea ice) has never been round in shape. Never.

  71. Steve Sadlov:

    RE: #68 (Lack of) spring in Northern California. Up until now, the most “Springless” year had to be either 2004 or 2005. But this year we are gunning for some new superlatives. We’ve been tricked twice this year into thinking Spring had sprung – once by a REX block back in early Feb then again the more recent one late April into Early May. Both broke down and were replaced by a Siberia Express set up (Ridge out by the date line and persistent trough nearer the W. Coast). We’ll likely have a Bering Sea storm this weekend – the only question will be, is it going to hit above or below 37N. But even anything below 40N is fairly well remarkable this late in the season.

  72. Dan Kamen:

    Hello everyone,

    I’m a 20 year old college student who stumbled across RC several months ago. I’m extremely interested in the current research on climate change and its ramifications for our planet but understandably I have very weak footing in the field.

    Please forgive me if my questions betray a misunderstanding of climate science. I’ve been attempting to understand the articles and debates on climate change with very little formal background. It’s a difficult excercise in interpreting technical jargon, so please excuse me if I’ve missed any important points.

    Recently I watched a film “Earth Changes, the Ripple Effect” the fourth documentary in a series entitled “Earth Rising” by Dr. Nick Begeich. Dr. Begeich mentions increased thermal venting in the artic oceans as a possible explanation for the currently inexplicable acceleration of warming in the region. (He cites a 5-15 degree increase in ocean temperature off the coast of Alaska during the late 90′s as evidence)

    Has RC ever discussed the impact of geothermic changes on the energy balance of our planet? Do we have any empirical data on ocean venting? Could natural increases in geothermic activity, perhaps due to the shift of the magnetic poles or other tectonic phenomena, coupled by anthropogenic warming explain the unexpectedly rapid disapearance of the polar ice sheets? And finally, if we lack the empirical data on geothermal activity in the oceans, isn’t it possible that our climate modles fail to include a huge contribution to the energy balance of our planet?

    I would like to thank all the people involved with RC and all the people contributing to the debates on each one of these articles! You set a standard of legitimate scientific debate that is tragically missing from public discussion, this website has been a great resource for me, thanks again!

  73. pete best:

    Reply #67

    Coal we have in abundance unfortunately, likely to last as long as 200 years. Oil comes in two generic flavours, light and heavy, by light we mean easy to extract and lots of energy return Oil, 1 trillion barrels used and 1 to 2 trillion barrels left or around 50 years worth, by heavy we mean less energy returned and hearder to refine etc, who knows how much of this we have, possibly some trillions of barrels. Gas at present rates of use will last around 70 more years if no more is found.

    All this fossil fuels provides 85% of our energy needs with a infrastructure to match. Fossil fuels will dominate for decades to come even if we could get the required 65% reduction in present levels by 2050 the climate will still be around 450 ppm and climbing.

  74. pat neuman:

    re 63.

    PHEaston,

    Your friend in Chicago should be happier now with warmer temps (and severe weather). I’ve been tracking monthly average temps at climate stations (those with more than 100 years of record). Jan-Apr temperature averages show positive 100 year trends at climate stations in ND and MN. Increasing trends for May and June precipitation are indicated for northeast ND (Devils Lake basin).

    The In-Forum (Fargo, ND) published my letter today called Climate change affects Devils Lake:
    http://www.in-forum.com/articles/index.cfm?id=127753§ion=Opinion

    Plots, 100 year temperature monthly and annual averages and precipitation at climate stations:
    http://pg.photos.yahoo.com/ph/patneuman2000/my_photos

  75. Hank Roberts:

    Dan (72): I found pages by Begeich searching on that movie title.
    He has a lot for sale. Caveat emptor.
    http://www.earthpulse.com/src/category.asp?catid=3
    http://www.earthpulse.com/src/productindex.asp#
    He doesn’t show up in Google Scholar, a good place to start checking science claims.

  76. Hank Roberts:

    Dan (72): midocean ridge spreading volcanic activity is discussed here:
    http://www.realclimate.org/index.php?p=306#comment-13591
    and following in the general thread on vulcanism. Short answer, it both produces (from fresh erupting lava) and absorbs (due to weathering of newly exposed lava) CO2 and these seem to balance; the rate doesn’t seem to have changed.

    While the midocean ridges are among the least accessible places on Earth, so far there’s no evidence they’ve made big changes in the atmosphere on balance, as compared to say the big basalt flows (“Deccan Traps” etc) occurring in the atmosphere.

    I found that by typing “spreading” into the Search box at the top of the home page here (remembering it was here, so I could sort it out from the fairly long list of posts that mention the word “spreading” retrieved.

  77. Alastair McDonald:

    Re Dan #72. The heat from the sun works out at around 400 watts per square meter. The geophysical heat from the core of the earth works out at about 40 mWatts per square meter. Thus the effect from geophysical heat is 0.01% of the heat from the sun, and it has no real effect even when concentrated at the mid ocean ridges because they are several thousand feet below the surface of the ocean. OTOH, the greenhouse effect of carbon dioxide is of the order of 4 watts per sq. meter, and its effect is amplified by water vapour to around 40 watts in round numbers.

  78. Willis Eschenbach:

    Gentlemen:

    This is quite frustrating. I attempted to post the following:

    According to GISS, the Svalbard station only started reporting temperatures in mid 1977. How did you determine the long-term (1961-1990) means (ybar) and standard deviations (sd)?

    Thanks,

    w.

    However, it seems to have been caught by the spam filter or something, as it has not appeared. Could you please fix this?

    Many thanks,

    w.

    [Response: The comment was most likely deleted because it was already indicated above that the record is available back to 1911, and the source of the data (Climatic Research Unit, not GISS) was already indicated. --mike]

  79. Hans Erren:

    re 78:
    Fair enough, but Svalbard Luft started in october 1977 and Isfjord Radio stopped with continuous recording in june 1976. How was the homogenisation obtained between the two stations. Moreover the nearest other station Bjornoya has the 50′s hotter than the 00′s, Which suggests an inhomogeneity in Svalbard in 1977.

    here is the giss list:
    0 km (*) Svalbard Luft 78.2 N 15.5 E 634010080002 rural area 1977 – 2006
    47 km (*) Isfjord Radio 78.1 N 13.6 E 634010050010 rural area 1912 – 1980
    425 km (*) Bjornoya 74.5 N 19.0 E 634010280003 rural area 1949 – 2006

    [Response: For any further details, you and any other interested readers should refer to the linked CRU website for information and references leading to an extensive body of literature that describes how CRU forms representative composite 5 degree latitude x longitude gridbox estimates (which is what is referred to here) that account for time-dependent sampling variations and potential inhomogeneities associated with the individual recording stations that fall within the same grid cell. --mike]

    [Response:(update) I was a bit careless in my wording. The long-term series from 1911 to date currently maintained by the Norwegian Met Service (and to which we are referring to here) is based on the combined record for the Svalbard airport and Isfjord Radio sites. The latter started in 1911. The Norwegian Met Service combined the two records in one of the recent nordic projects, and any inhomogeneities were taken into account in the process. There is little doubt that the anomalies observed so far this year are unprecedented as far back as the measurements go (early 20th century). - mike]

  80. Piers Corbyn:

    YOU SAY: “There is currently an absence of sea ice off much of the coast of Svalbard, which is also unprecedented for so early in the year.”

    This claim is FALSE. I refer you to (HMSO 1964) Met Office ‘Weather in Home Fleet Waters, Volume 1: Northern Seas, Part 1

    A clear map on page 256 of Ice limits for APRIL shows ‘open years’ and ‘heavy years’ which flip-flop to exclude and include Svalbard – West& South coasts – from pack ice. What you claim is ‘unprecedented’ is in fact completely normal. Indeed page 247 states: “…Within this triangular sea (West of Spisbergen) ice is unusual even in April.”

    Thank you – piers@weatheraction.com

    [Response: We should have been more precise in our wording. It is true that April is sometimes ice free. It is very unusual that January is ice free, which was the case this year. The only way to get the type of anomalies seen this year is to either get rid of the sea ice or to have continual southerly advection. --mike]

    [Response:To add to Mike's comment, it's also usually the late winter and early spring when the sea ice-cover is greatest in the Arctic, and my colleagues can inform me that the ice-extent this winter, also April has been unusual (winds blow the ice around, and sometimes open waters in the Arctic may arise from that reason - the wind directions also play a role for the temperatures as well). It is also important to look at the larger region, not just in selected locations, but rather the entire Arctic to get the picture. High quality sea-ice data do not go back in time very far, so I'd only trust the measurements since 1979 (after satellite observations start). If you look at the HadISST1.1 data (1979-1999; which I happened to have at hand), then the mean ice-cover edge tends to be located around Svalbard. Looking at the ice-cover for April 1990, which is an April with the minimum ice cover in the area for the 1979-1990 interval, you still don't see completely ice-free waters east off Svalbard for the entire month. For those of you who understand Scandinavian, there is an article about this on met.no (posted as early as 27.01.2006) -rasmus]

  81. Ferdinand Engelbeen:

    There seems to be some correlation between sea ice extent around Svalbard and the temperature record of Jan Mayen (some 1100 km SW of Svalbard). From E. Isaksson e.a.:

    The Austfonna record correlates well with the temperature record from the more distant and southwesterly located Jan Mayen. A comparison of the ice-core and sea-ice records from this period suggests that sea-ice extent and Austfonna 18O are related over the past 400 years. This may reflect the position of the storm tracks and their direct influence on the relatively low-altitude Austfonna.

    According to the GISS database, the temperature record of
    Jan Mayen shows near as high temperatures in the period 1930-1960 as in the past years…

  82. Steve Bloom:

    This seems as if it would have major implication from the poles to the tropics: http://www.mercurynews.com/mld/mercurynews/living/health/14666521.htm . Sounds to me like a post topic.

  83. John C Wilson:

    5 standard deviations is huge. You are reporting an anomaly that is ongoing January to April. Has someone yet looked to find a proximate cause or are we purely at observation? One thing that occurred to me was that we could be seeing the result of a local methane release but that one does not square well with high Jan. temps when there would be no sun at Svalbard. Any other hypotheses?
    Also, as a 54-year resident of Chicago: the first 3 weeks of December were frightful, esp. since a mild Oct & Nov meant no acclimatization. After that, no winter. It could be St. Louis or Louisville. April was the mildest and most consistent in my memory or in my bicycle diaries by a long shot. May has been uneven but warm. And set to finish in the 90′s.

  84. Hank Roberts:

    The problem is that comment tools have no standard for “character encoding” — and web pages may have any of a dozen different character encodings. See your browser’s “view” menu in Firefox for example. What we see is a picture (font) but what’s behind that — and what’s actually cut there and pasted here — is a computer code (hexadecimal, octal, binary, HTML). So when you paste something in, it brings with it its encoding — then the comment software managles that, and your browser’s set to whatever View option you chose so it interprets the mangle as a garble and displays that on the screen.

    Someone technically competent can probably clarify that. I don’t think there’s a solution except to post a link to the actual page instead of cutting and pasting — using hypertext as it should be used, eh?

  85. Hugh:

    Sorry, I appreciate this is an inappropriate use of this thread but I’m hoping someone can point me in the right direction toward a graph.
    A couple of months ago I recall seeing a very useful plot of CO2 emissions over the last 650,000a, and now I can’t find it again.
    Before you jump to conclusions about my stupidity…it’s *not* the one attached to the 650,000 RC thread, but one that more clearly showed current and, I think, projected concentrations as well.
    Any help gratefully received

    Hugh

  86. Coby:

    Hi Hugh,

    These are not the precise time period you requested but try here:
    http://en.wikipedia.org/wiki/Image:Carbon_Dioxide_400kyr.png
    and here:
    http://www.brighton73.freeserve.co.uk/gw/paleo/20000yrfig.htm

  87. joel Hammer:

    “By giving the appearance of symmetric feedback, people have an excuse to say, ‘Maybe we don’t have to worry so much,’” Harte said. “But while there are uncertainties in the feedbacks, all the major feedbacks are positive, meaning they would increase warming, and we know of no significant negative feedbacks that would slow warming.”

    Comment by Hugh – 23 May 2006 @ 11:38 am

    This is one reason why skeptics like me exist. Nobody on this scientific message board has challenged this statement, so I guess you all believe this or just keep your doubts to yourselves. No significant negative feedbacks exist in nature on global temperature? How do you explain the Ice Age? How do you explain why runaway global warming hasn’t occurred before now?

    [Response:On the ice age, you have it backwards. If there were significant negative feedbacks we didn't know about, then in fact it would be very difficult to get an ice age with the relatively small forcings Nature provides. With regard to lack of spontaneous runaway global warming in the past, it would be fair to say that the increase of infrared emission to space as temperature increases constitutes THE fundamental "negative " feedback allowing climate to equilibrate. Harte's comment was addressing the uncertainties in the climate sensitivity, and I didn't see anything in his remark that implied exclusion of a process like increase of emission with temperature. With regard to climate sensitivity in the next few centuries, the issue is how steeply emission increases with temperature, and there, on the whole I think Harte had it right. We know of a great many positive feedbacks that could increase the sensitivity well beyond the mid-range of the IPCC sensitivity, but we know of essentially no plausible feedbacks that could reduce the sensitivity substantially below the lower end. Now, between the low end and the mid range of IPCC sensitivity, there are indeed some cloud feedbacks operating that could be considered "negative" feedbacks, and in that range it would be justified to qualify Harte's remark somewhat. Still, it takes a rather special set of circumstances for clouds to significantly damp climate sensitivity and I think it's fair to say that we know of a lot more mechanisms that could potentially increase climate sensitivity. --raypierre]

  88. Karen Street:

    For #87, positive feedback doesn’t mean increasing temperature and carbon and negative feedback doesn’t mean reducing the same. There is positive feedback if you are headed in a direction — temperature and carbon up or down — and changes on Earth positively reinforce this shift. As the Earth warms, there is less ice so reflectivity goes down so the Earth warms more. As the Earth cools, there is more ice, so reflectivity increases and the Earth cools more. Both are examples of positive feedback.