RealClimate logo


Unforced variations: Mar 2011

Filed under: — group @ 1 March 2011

This month’s open thread for climate science discussions.


206 Responses to “Unforced variations: Mar 2011”

  1. 1
    Daniel J. Andrews says:

    This is also off-topic. This abstract just came into my inbox today from Nature Climate Change.

    It says that an irreversible decline in Arctic sea ice is unlikely this century, as the mechanisms they’ve modeled lead to a consistent recovery of sea ice in just a few years.

    The abstract for the same paper at this AGU link puts a different emphasis on their findings, so now I’m wondering what the paper itself says, and what other experts think.

    I also wonder how many contrarians will embrace this paper despite it’s conclusions being based on models that contrarians been decrying as unreliable all these years.

    [Response: The issue is that *if* we reduced emissions and concentrations of anthropogenic greenhouse gases, sea ice would come back. i.e. what is happening is not technically irreversible. However, the recovery is predicated on reducing emissions and concentrations - it is not any kind of prediction. Rather it is a statement about how non-linear the regime is and on whether there are real and large scale tipping points in this system. The whole issue is moot in the absence of emissions reductions. - gavin]

  2. 2
    wili says:

    Speaking of extremes, has there been a discussion of the Royal Society publication that recently came out full of studies about what the consequences of a 4 degree rise in global temperature will be?

    http://rsta.royalsocietypublishing.org/content/369/1934/6.short

  3. 3
    EFS_Junior says:

    Maybe we need a new open thread to discuss BEST?

    I’d rather not do it here, as that would severly sidetrack this thread.

    I have my own thoughts on what BEST will do and how they will frame there results in terms of uncertainty.

    But I’ll wait for a new open thread first.

    Suggest people stay on topic or have this thread closed if not.

  4. 4
    Alfio Puglisi says:

    As an IT professional, I have some idle curiosity about the requirements to run climate modes. How much computing power is needed for a decent simulation? What kind of computers are used? Traditional supercomputers? PC clusters? I also wonder how long it takes for a 100 year model run. Days? Weeks? Months?

    [Response: State-of-the-art models generally take a month or so to run 100 years (and this has been true for decades), but what is considered 'state-of-the-art' changes quite quickly as a function of computing resources. Given the speed of development, you can generally run 'state-of-the-art' models from a few years ago on a present day desktop (or even a laptop). However, given the amount of data these models output, you might want to be a little selective in exactly what kind of simulation you want to do (fully coupled oceans are expensive, as are interactive aerosols and chemistry, but AMIP-style AGCM simulations are relatively easy). For instance, the speed up of the GISS AR4 model over our AR5 model is around a factor of 10. - gavin]

  5. 5
    Ken Rushton says:

    Looks like we just may have passed peak ice extent in the northern hemisphere on February 17. To me it looks like there’s less than a 50% chance that there will be any further peaking. And the ice is quite thin , espcially considering this was a La Nina year.

  6. 6
    Jaime Frontero says:

    @ #3 -

    BEST? The EU BioEthanol project?

    Gavin – I note that the list of acronyms was posted on November 27th of 2009, and does not appear to have been updated since then…

  7. 7
    Greg Simpson says:

    To me it looks like there’s less than a 50% chance that there will be any further peaking.

    I’d guess it’s more like 90% that we haven’t peaked yet. I’d wait awhile before claiming a peak.

  8. 8
  9. 9
    SecularAnimist says:

    Jaime Frontero wrote: “BEST? The EU BioEthanol project?”

    BEST is the Berkeley Earth Surface Temperature Study.

  10. 10
    Dan H. says:

    Ken,
    It seems unlikely that we have passed peak ice extent this early in the season, althought it is certainly possible. Each of the past six years peaked in March, as is generally the rule (last year actually peaked in April). If you look at the chart below, you can see several bumps and dips each year which are likely due to changes in wind or ocean currents. If it were to have peaked a few days ago, then it would be the lowest recorded maximum ice extent (slightly below both 2006 and 2007). The final verdict will not be in for another month yet.

    http://ocean.dmi.dk/arctic/icecover.uk.php

    In response to the Nature article, I am inclined to agree with them. Much of the loss in sea ice has occurred in the open waters were the Arctic and Atlantic Oceans meet. Mixing of the warm Atlantic resulted in significantly melting of the exposed ice. The remaining sea ice rests in colder Arctic waters and further from the warm currents.

  11. 11
  12. 12

    http://www.youtube.com/watch?v=IaKQCY5ybMY

    I found this article very hard hitting against the AGW contrarian crowd,
    not because it is loud, rude, and direct to the point, but because it props up
    clear compelling reasoning against the minority of people who attack science
    for breakfast before they cut funds for it come lunch time.

    I also am finding weird extreme arctic tropopause heights regularly, despite finally normal seasonal temperatures returning,
    this is highly unusual, and comes with high RH just at the tropopause. Raypierre may explain,
    but its been discussed a bit, as high 500 mb heights anomalies:

    blogs.agu.org/…/01/…/while-the-u-s-shivered-amazing-arctic-warmth/

    In January that was OK, since surface temperatures were way warm +7 to 30 C above normal on some high Arctic stations
    mainly over Nunavut. But the high heights continued as winter finally settled in.

    My understanding of this is not certain, and would love to hear Raypierre’s take…

  13. 13

    I would like to read Raypierre’s take on the following:

    blogs.agu.org/…/01/…/while-the-u-s-shivered-amazing-arctic-warmth/

    of which high Arctic tropopause heights have persisted, even after January’s incredible surface temp anomalies
    have subsides. Tropopause heights are very high along with RH even though seasonal temperatures
    have returned for the first time in months.

    I have never seen this. Only Raypierre may have an idea???.

  14. 14
    Daniel J. Andrews says:

    Thanks for the prompt response, Gavin. I’ll have to download the paper next time I’m at the university.

  15. 15

    blogs.agu.org/…/01/…/while-the-u-s-shivered-amazing-arctic-warmth/

    High Arctic tropopause heights have persisted despite the return of seasonal Arctic temperatures in February.
    This is Highly unusual. never seen this before. Its OK for the Tropopause to be high when surface temps are +7 to +30 C above normal
    (as it was in some high Arctic stations in January) .
    But the trop is as High as 10 K when surface temps are -30 to -35 C. May be Raypierre can explain..

    Also:

    http://www.youtube.com/watch?v=IaKQCY5ybMY

    This is how to convince anti-AGW believers that something is not quite right at their leadership level…

  16. 16
    Alfio Puglisi says:

    Thanks Gavin, that was interesting. A running time measured in months is surely a big incentive to good software management! Sounds like there is the opportunity for big speedups in proper matching of the software with specialized parallel hardware – but that has probably already looked into (and it’s enough to get a good-sized team’s hands full).

  17. 17
    Chris Dudley says:

    Wish these threads could be weekly or remain going the whole month. Got to get here quick or everyone has left.

    Getting back to the rain in Spain falling only on the plain from a while back, I took a look at the GISS model E precipitation output for 8 times carbon dioxide and it looks as though precipitation falls for most mountain ranges aside from the Andes. http://data.giss.nasa.gov/cgi-bin/cdrar/effij.py

    Spain, unfortunately, gets substantially less rain everywhere.

    So, as a result of the ‘accidental’ arrangement of continents, the effect of warming may be to reduce the amount of new silicate rock surface exposed by physical weathering and available to chemical weathering. It is not clear that this fully counteracts faster chemical weathering reaction rates at higher temperature, but if it does, then the limestone thermostat might be broken and the Venus Syndrome discussed in James Hansen’s new book not halted by that mechanism. Based on the rightmost carbon dioxide point in fig. 30 of that book, I deduce that a sixteen times carbon dioxide run has been conducted which was not reported in the 2005 Efficacy paper. I’m preparing to try to get that output to see if the precipitation in the mountains continues to fall with more warming.

    Surly new rock surface will be exposed in Greenland and Antarctica as ice sheets are eliminated which should also affect the limestone thermostat.

  18. 18
    dhogaza says:

    Alfio Puglisi:

    Sounds like there is the opportunity for big speedups in proper matching of the software with specialized parallel hardware – but that has probably already looked into (and it’s enough to get a good-sized team’s hands full).

    Gavin’s pointed out that their models have taken about a month to simulate about 100 years for “decades”.

    The point is that as computer power continues to increase, they add more to the model or increase resolution to take advantage, rather than simply run the same model in shorter time.

    The goal being skewed towards “better” rather than “faster” …

  19. 19
    Ken Rushton says:

    Re: #5 – that should have been Feb 27, not Feb 10; my typo.

    and #10:
    It seems unlikely that we have passed peak ice extent this early in the season, althought it is certainly possible.
    I’m basing my guess on three facts:
    (1) On the nsidc graph, the peak usually comes in the first 2 weeks of March,
    (2) In the last two days, the extent has declined such that it would be difficult to make up in the next 2 weeks.
    (3) There’s a lot of abnormally warm air over the ice edges (and the pole as well), as shown here . This has always, in my observation, preceded ice loss.
    Ken.

  20. 20
    Tom Flahive says:

    I read a really interesting article in the November 2010 issue of The Atlantic about a “meta-researcher” by the name of John Ioannidis who has found that most of what is published in the field of medical and nutritional research is “misleading, exaggerated, or flat-out wrong” (http://www.theatlantic.com/magazine/archive/2010/11/lies-damned-lies-and-medical-science/8269/#). As the article describes, Ioannidis “charges that as much as 90 percent of the published medical information that doctors rely on is flawed,” and the article goes on to explain the many areas where the errors are coming from. Mostly they come from some form of researcher bias.

    Although I think the science for climate research is solid, and I am a regular reader of Real Climate because I think it is the most trustworthy voice on climate change, if there was one area that I thought climate science might be vulnerable to criticism, it would be in the areas discussed in this article, only because this is a potential weakness that faces all of science. This article brought to mind a couple of questions:

    1) Are there any meta-researchers in the field of climate science, similar to John Ioannidis, who look at the science being published to make sure the methods are robust and the papers don’t suffer from the problems identified in this article?
    2) Is there something about climate research that makes it different from medical and nutritional research such that it is a lot less likely to face the same problems?

    For example, in drug research there are billion dollar incentives for finding that a particular drug has some beneficial effect. I don’t really see the same distorting incentives in climate science (although climate science deniers like to claim otherwise).

  21. 21
    John McManus says:

    Tom Flahive:
    I have had a subscription to the Atlantic for years, but have declined to renew. They still send me issues but no more money will flow their way.

    A once good magazine has become a neo-con rag. it has also become somewhat slimmer. Content and advertising both seem to be suffering.

    I read the article you mentioned. It seemed to me to be unsubstantiated twaddle , written to satisfy the anti-science bias of an editor.

  22. 22
    sidd says:

    Ross breakup:

    http://www.stuff.co.nz/national/4708428/Emergency-airlift-at-McMurdo-in-strife

    Isnt there a tidewater glacier there too ? i seem to recall a paper about stick-slip motion in a tidwater glacier by bindschadler(?) but that was on the other side of the ross shelf…

  23. 23
    Witgren says:

    Alfio — related to your question, there is a grid computing project at http://www.climateprediction.net that allows participants to contribute computing time on their own home computers to run climate simulations in the background or during computer down time. You might take a look at the project and see what information they have vis a vis their models and hardware requirements.

  24. 24
    SecularAnimist says:

    Tom Flahive wrote: “… in drug research there are billion dollar incentives for finding that a particular drug has some beneficial effect.”

    The fossil fuel corporations collectively rake in over one billion dollars PER DAY in profit — not revenue, but PROFIT — from business-as-usual consumption of their products.

    That’s a pretty strong incentive for finding that fossil fuels have no harmful effects.

  25. 25
  26. 26
    Steve Bloom says:

    Re #15: Wayne, could the explanation be warmer temps higher in the troposphere? Alternatively, is it posssible that one of those stratospheric warmings is starting?

  27. 27
    Mike says:

    @Why Are Republicans Against The Science?
    http://www.youtube.com/watch?v=IaKQCY5ybMY

    A small ray of hope:
    http://www.rep.org/
    http://www.climateconservative.org/

    I’d like to suggest RC place these on your “Other Opinions” list.

  28. 28
    Hank Roberts says:

    The sea ice around Ross Island (Antarctica) does break up — William (Stoat) said he hasn’t heard anyone associated with the Antarctic bases expressing surprise. Sounds like more of an inconvenience.

    Here’s a quite old source showing the ice edge over 1956-1962 (it’s quite variable; compare the map there to contemporary maps to see the airstrip location on those, it’s around the area indicated as having pressure ridges I think); found searching Scholar for \ross island\ breakup \open water\

    ICE BREAKOUT AROUND THE SOUTHERN END OF ROSS lSLAND, ANTARCTICA
    AJ HE1NE – New Zealand Journal of Geology and Geophysics –
    … During the spring and summer this fast ice gradually breaks up and floats out to sea … The break up of ice in McMurdo Sound, photographed on 16 January 1962, looking north-east towards Ross Island. …
    Cited by 15
    http://books.google.com/books?hl=en&lr=&id=eiE4AAAAIAAJ&oi=fnd&pg=PA395

  29. 29
    ianash says:

    I am extremely cynical about the BEST project:

    1. If done properly, at best (no pun intended), it will largely reconfirm what is already known.

    2. If done badly, it will create major confusion and more mess for climate scientists to clean up.

    3. Any minor variances in trends, graphs etc will set off a new denialist frenzy.

    4. Richard Muller, the spokesperson about the project, continues to make ‘hockey stick is broken’ claims. Hardly an open and inquiring mind.

    5. The ‘team’ on BEST has quite a few members who are also business associates of Richard Muller through his company Muller & Associates. These include:
    - Elizabeth Muller
    - Arthur Rosenfeld
    - Jonathan Wurtele

    6. Judith Curry is the climate expert on the group. I’ll say that again. Judith Curry is the climate expert on the group. I think the nicest thing I can say is that it perhaps would have been wiser to obtain the services of a climte scientist with experience in this area, if the project wished to promote its credentials.

    7. Funding in part comes from a Koch co fund. The perception here is bad. Judith Curry said they thought it was a good idea to get money from Gates and Koch as some sort of balancing act. Well this has backfired.

    8. Not all funding sources are named. This is a bad look.

  30. 30
    Damien says:

    In case anyone is interested, the Australian (Labor minority) Government have announced that they intend to legislate some sort of carbon price to be implemented mid-2012. The conservative opposition Liberal/National Party are opposing it tooth and nail.

    The plan is a (yet unnamed) fixed price for 3-5 years followed by a full cap-and-trade system. Not yet announced are concessions to household and industries. The previous scheme, the Carbon Pollution Reduction Scheme was rejected by the senate in 2010 and saw the fall of both the sitting Prime Minister and Opposition Leader over the issue.

    No doubt there will be some noise on this over the next little while, so brace yourselves!

  31. 31
    Trent1492 says:

    Richard Muller is going to give a talk U.C Berkley. The title of the talk is The Current Status of Climate Change – A Non-Partisan Analysis. The Q & A should be interesting.

  32. 32
    Mike says:

    @27: And there they are it! Thanks. I could not convince Romm or Watts to include REP.

  33. 33
    ianash says:

    @Damien 30

    ‘some noise’. You have a great way of understating things.

    The conservative party has gone ballistic. The right wing shock jocks are turning purple! And we have ‘Professor’ Bob Carter proclaiming all sorts of weird and wonderful things:

    http://www.quadrant.org.au/blogs/doomed-planet/2011/02/carbon-dioxide-tax-the-people-s-revolt

  34. 34
    Ray Ladbury says:

    Ianash,
    OK, I don’t know either Muller, but Art Rosenfeld is a pretty reasonable guy, and in my interactions with Wurtele, he seemes fairly reasonable as well. Neither of them has any particular expertise in climate. OTOH, it would be nearly impossible to make the warming signal go away without outright fraud

  35. 35
    Hank Roberts says:

    Also now at BEST, Robert Rohde — he has been contributing to climate education for years, turning out useful charts at the same time he’s been working on his PhD.

    “Robert Rohde, a young physicist who left Berkeley with a PhD last year, does most of the hard work. He has written software that trawls public databases, themselves the product of years of painstaking work, for global temperature records. These are compiled, de-duplicated and merged into one huge historical temperature record. The data, by all accounts, are a mess. There are 16 separate datasets in 14 different formats and they overlap, but not completely. …. Rohde has gathered records from 39,340 individual stations worldwide….

    Peter Thorne, who left the Met Office’s Hadley Centre last year to join the Co-operative Institute for Climate and Satellites in North Carolina, is enthusiastic about the Berkeley project but raises an eyebrow at some of Muller’s claims. The Berkeley group will not be the first to put its data and tools online, he says. Teams at Nasa and Noaa have been doing this for many years. And while Muller may have more data, they add little real value, Thorne says. Most are records from stations installed from the 1950s onwards, and then only in a few regions, such as North America. “Do you really need 20 stations in one region to get a monthly temperature figure? The answer is no. Supersaturating your coverage doesn’t give you much more bang for your buck,” he says. They will, however, help researchers spot short-term regional variations in climate change, something that is likely to be valuable as climate change takes hold.

    Despite his reservations, Thorne says climate science stands to benefit from Muller’s project. “We need groups like Berkeley stepping up to the plate and taking this challenge on, because it’s the only way we’re going to move forwards. I wish there were 10 other groups doing this,” he says….”

    http://www.guardian.co.uk/science/2011/feb/27/can-these-scientists-end-climate-change-war

  36. 36
    Marlowe Johnson says:

    @29
    Arthur Rosenfeld is about as straight up as they come. One wonders how and why he got involved.

  37. 37
    Bern says:

    I heard on the radio this morning that one of the independent MPs here in Australia that supports the carbon price has started receiving death threats because of it…
    http://www.abc.net.au/news/stories/2011/03/02/3152798.htm?section=justin

    So much for informed public debate on the issue…

    Oh well, at least we have sites like RC & SkepticalScience to point people at for real, verifiable information.

  38. 38
    John E. Pearson says:

    34 Ray. I’m not sure if Muller is in the NAS, I guess maybe not, but in his book “Physics for Future Presidents” he said that he reviewed the hockey stick for the NAS . He said words to the effect that it is warmer now than in the last 400 years with certainty (or near certainty) and the certainty goes down with time further into the past but that it is likely warmer now than in something like 1000 years. I found him annoying. I’m not sure how much misinformation the book contains in general but it there were significant gems in there, such as reactor grade plutonium can’t be used to build bombs. If I had to choose between Burton Richter’s Beyond Smoke and Mirrors and Mullin’s Physics for Future Presidents, Richter wins hands down. Richter covers energy and climate. Mullins covers energy and climate plus lots of other stuff. I didn’t get the impression that Mullins had actually researched his subject. To me it seemed a lot like two physicist’s in a bar late at night trying to show each other up by pontificating on subjects they know nothing about.

  39. 39
    ianash says:

    @34, 36

    I dont make any comment on whether or not Rosenfeld and Wurtele are straight shooters, only that they are also listed as business associates of Muller & Associates on his consulting website. My perception is that it all looks very clubby – something that Muller and Curry have been quick to denounce in other areas.

  40. 40
    Susan Anderson says:

    BEST association with denialist Will Happer of Princeton – definitely not good.

    I heard that Fred Singer likes it. Also, standard climate cranks (I like that term) are beginning to explain to anyone who will listen that it will save us from ourselves.

    [Response: Whatever Singer says, you can safely assume the opposite is true. I have not heard of any connection of BEST to people like Happer though - do you have a reference for that? - gavin]

  41. 41
    ccpo says:

    @ Sea ice was thin a week ago. Site is has not been updated for almost a week. http://tinyurl.com/6ajzhzc Very little over 1.5M.

  42. 42
    AIC says:

    (Repeating from the tail-end of Unforced Variations for February)

    Any comments on this?

    http://www.pnas.org/content/early/2010/02/02/0906548107.abstract

    http://www.nasa.gov/topics/earth/features/road-transportation.html

    Attribution of climate forcing to economic sectors

    1. Nadine Unger
    2. Tami C. Bond
    3. James S. Wang
    4. Dorothy M. Koch
    5. Surabi Menon
    6. Drew T. Shindell and
    7. Susanne Bauer

  43. 43
    P. Lewis says:

    I couldn’t find any BEST/Happer link myself with a quick Google, but I did turn up The Truth About Climate Change Open Letter — Open Letter to the United States Congress: 8 February 2011 he is a signatory to, a letter that references the Center for the Study of Carbon Dioxide and Global Change and the NIPCC’s Climate Change Reconsidered: The 2009 Report of the Nongovernmental International Panel on Climate Change as two recent compilations of scientific research to consult!

    Did this ‘important’ contribution to the climate ‘debate’ get overlooked in the Pearcegate/Tallbloke furore? (Well, it did by me anyway!)

    Oh, BTW, sorry for raising it if it did get overlooked, because it should obviously have stayed overlooked!

  44. 44
    Ianash says:

    @40
    I think it might refer in part to this article

    http://online.wsj.com/article/SB10001424052748703514404574588673072577680.html

    Muller says:

    “Another option is that we could learn to live with global warming. Despite claims to the contrary, storms aren’t increasing. The rate of hurricanes hitting the U.S. coast has been constant for a century, and the number of damaging tornadoes has been going down. Will Happer, a former director of research for the Department of Energy, argues that additional CO2 may have helped the agricultural revolution. And chilly Berkeley might be nicer with a few degrees warming.”

  45. 45
    Ray Ladbury says:

    John Pearson,
    I’d say so far, I’m agnostic on BEST. Unless it is a complete fraud or done with utter incompetence, it should show warming comparable to the other 5 indices. If it does not, I am sure that it will be exposed for what it is–though this will take time. If it does show comparable warming, the denialists will denounce it as a fraud even if they put it together. The web-trolling seems to me to be a novel but risky strategy. One wonders how much they know about the data series they are using.

    The thing about nature is that she tends to give consistent answers as long as you ask the right questions.

    The whole idea of advising Presidents is a rather fraught proposition. Most aren’t interested in science. I think we need a book that advises the people about what they need to know about science–maybe then they’d elect better Presidents.

  46. 46
    EFS_Junior says:

    With respect to the BEST Team, here is what I would conjecture at this point time given the pre-PR PR, and the “proported” involvement of you know who at WUWT? infamy;

    Researchers doing what researchers do, they will likely want to make some “bold” statements about their analyses. I mean, if it’s the same old same old (agrees with the existing global SAT from “the establishment”), it’s not going to be newsworthy in the least, and will be seen by the MSM as a complete waste of time (IMHO).

    I’m also not sure what it means to include all of the data from all stations, as we pretty much know that there is a very high degree of spatial autocorrelation, and that the spatial density of SAT sites is highly biased (concentrated) in urban areas (e. g. the dreaded UHI will rear it’s ugly head).

    The BEST Team will do the usual; land vs ocean SAT’s (look see land is warming more that oceans), rural vs urban SAT’s (look see urban is warming more than rural via UHI), the usual geopolitical regions (look see CONUS is different than the rest of the world, d’oh), decadal (and longer) natural variabilities (look see ocean indices and ENSO and volcanos, oh my) junk.

    If the BEST Team does not publish there results in the highly respected peer reviewed climate science literature, we can pretty much conclude that this BEST Effort was largely political in nature, and not aimed at any improvement in our current understanding of the Global SAT temperature record.

    My thoughts (call it a hunch) are that the BEST Team will try to claim higher uncertainty in the global and regional SAT’s than is commonly accepted by the scientific community today. You just have to make the front page of the NYT, don’t you know?

    Conjecture OFF!

    Having recently downloaded most of Canada’s HAWS (an aggrigate of 23 onshore stations using an anomaly period of 60 years (1951-2010)), Greenland’s (west onshore side, same anomaly period, after a data request to DMI (the just released their 1958-2010 report on daily temperature records, I’ll be looking at the northeast, north, and northwest), and Norway’s Svalbard (and other high latitude island onshore locations for Norway, same anomaly period), I will look on in keen interest as to what the BEST team has to say about high Arctic warming.

    What’s different here is that all data is raw daily temperature records, no monthlies, no annuals, which let’s me do some FFT’s (and other filtering techniques) and spot higher harmonics in the temperature record (once the records are made stationary, of course), which dovetails rather nicely with similar work I’ve done with the UIUC sea ice area daily time series. Got to prepare for the upcoming SIO, you know.

    My own analyses suggest an overall warming of ~4C since the early 1920′s and an overall warming of ~3C since the early 70′s (most pronounced for the upper Canadian Archipelago (Eureka, Resolute, Mould Bay, Isachsen, and Alert, the original 5 HAWS)). Current warming in that region is ~0.25C/yr +/-0.15C/yr, quite (Dare I say it?) “alarming” actually. The overall pattern is consistant with the overall global SAT, warming from the early 20′s through the mid-40′s, flatline/cooling until the early 70′s, than a very dramatic and apparently accelerating warming period to the present.

  47. 47

    4: “he speed up of the GISS AR4 model over our AR5 model is around a factor of 10. – gavin”

    BPL: I assume you got AR4 and AR5 reversed here? Or are you saying the earlier model, because it’s simpler, takes less time to run?

    [Response: The older model has coarser resolution and less 'stuff', and so is much faster. -gavin]

  48. 48
    Ray Ladbury says:

    The worries about BEST remind me of the story about U. S. Grant before his first battle against the Army of Northern Virginia. He overheard some of his officers speculating about what Lee would do and upbraided them saying he didn’t want to hear about what Lee was going to do to them but rather what they were going to do to Lee.

    It is pretty much beyond question that the planet is warming. We have 5 more or less independent datasets that show comparable trends. At its worst, BEST will be wrong. Wrong isn’t so bad. Wrong is correctable–just at UAH was correctable. The arguments we need to worry about are the ones that are “not even wrong”. The people advancing them can’t be persuaded by evidence.

  49. 49
    Hunt Janin says:

    If you happen to know of any websites that show which world cities are most at risk from sea level rise, I’d be very grateful if you could tell me off-list at huntjanin@aol.com.

    Thanks

    Hunt Janin

  50. 50
    Michael Doliner says:

    Climate science is complicated, but it seems to me the question is easy. If the earth retains more of the suns heat that heat must either raise temperatures or be used in some other way. Is there any other way that this heat might be used other than in melting ice, that is what we called in high school the heat of fusion?


Switch to our mobile site