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Unforced Variations: Jan 2013

Filed under: — group @ 1 January 2013

A new year… so comments reflecting the past year in climate science, or looking forward to the next are particularly apropos.


301 Responses to “Unforced Variations: Jan 2013”

  1. 1
    Donald says:

    Does anyone know why there appears to be open water near the North Pole in the NCOF charts? See a chart collection at https://sites.google.com/site/apocalypse4realseaice2012/home/sea-ice-concentration-and-thickness-comparison , which indicate that the open water developed about Dec 24. Thanks

  2. 2
    David B. Benson says:

    Donald @1 — Probably because there is open water at that spot. But it is a looong way from there to the North Pole.

  3. 3
  4. 4
    Donald says:

    David, the charts I mentioned show dark blue right next to the ’90 N’ label. Not that long a distance.

  5. 5
    Hank Roberts says:

    Donald, I’d guess there’s something odd with the imagery they generate around the pole at that”apocalypse4realseaice…” page, I’d guess; all its images have something odd around at the pole.

    You might want to compare the sources that page cites, it says it gets the first image’s data from
    http://data.ncof.co.uk:8080/ncWMS/godiva2.html
    which generates a Mercator (I think) rather than a polar projection. Or dig deeper and find the data set they’re using. Remember no “polar orbiting” satellites track directly over the poles: http://www.rap.ucar.edu/~djohnson/satellite/coverage.html#polar
    http://www.rap.ucar.edu/~djohnson/satellite/figures/polar1.gif

    or compare
    http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn/nowcast/ictn2012122618_2013010100_035_arcticictn.001.gif

  6. 6
    T Marvell says:

    post #1. That’s probably missing data. North pole maps often have missing data around the pole.

  7. 7
    Candide says:

    It’s no secret to people who read this site that 2012 was a record breaker in terms of Arctic sea ice melt. I’m very curious to see what happens in the summer 2013.

    One thing I have been trying to learn more about is the AMSR-2 climate satellite. My understanding is that it was launched in May of 2012 but that it is still undergoing calibrations and testing. No real info yet on when it “goes live” and starts sending back what is expected to be the most accurate data yet on polar ice. I went googling for info and came up with surprisingly little. This is the most recent article I could find, and it wasn’t very detailed:

    http://www.jaxa.jp/projects/sat/gcom_w/index_e.html

    This is a Japanese satellite. Seems that NASA doesn’t have the funding to do anything similar, and the old Aqua satellite was allowed to die with no replacement planned.

    Does anyone know more about what is happening in this (climate satellite) arena? Are the Europeans doing anything?

  8. 8
    David B. Benson says:

    Donald @4 — Yes, I think you are right:
    http://geology.com/world/arctic-ocean-map.shtml
    Hank Roberts @5 seems to have nailed it; the image generator does not fill in properly where there is no data.

  9. 9
  10. 10
    Jim Galasyn says:

    50 doomiest stories of 2012

    At some point, the pace of doom will overtake this blog’s capacity to document it. In 2012, Desdemona came pretty close to this threshold, as a burst of extreme weather events battered civilization and illustrated the nature of abrupt climate change to the most obdurate of nation states.

  11. 11
    sidd says:

    What is this paper ? the link in the article seems broken and i see nothing in GRL December ? No author names are given in the article either…

    sidd

  12. 12
    sidd says:

    sorry, i didnt put in the link
    the paper is referred to here

    http://green.blogs.nytimes.com/2012/12/31/light-absorption-speeding-arctic-ice-melt/

    sidd

  13. 13
    GeoffBeacon says:

    Ron Broberg #3

    Have you seen Bob Watson’s presentation at the Meeting of the AGU (Fall 2012)?

    In this presentation he points out that rather than a fall in CO2 emissions by the UK since 1990 as sometimes claimed (I remember 22%) that when the CO2 embedded in imports is counted there has been a rather large increase (I think 18%).

    The UK imported goods more goods that were made abroad during this period – from countries like China. They emitted CO2 on the UK’s behalf. As Professor Watson says, the CO2 from the manufacture of these goods should really go on the UK budget.

    I expect it will be much the same for the US.

    Bob Watson does actually work for the UK government.

  14. 14
    Tom Adams says:

    In March 2009 the White House and some environmental groups decided to avoid references to climate change as a political strategy, substituting various euphemmisms.

    http://www.guardian.co.uk/environment/2012/nov/01/obama-strategy-silence-climate-change

  15. 15
    glen says:

    #3Ron Broberg and #13Geoff Beacon

    One of the better papers on the subject is at http://supplychainco2.stanford.edu/paper.html

  16. 16
    Sean says:

    This may be a dumb question (please don’t lol) – where people NOAA, IPCC etc mention Ocean & Land surface temperatures are they ONLY speaking to the AIR TEMPS measured near the surface?

    In that, when someone speaks about ocean temps, they are not actually talking about the average temp of the “water” but the air just above it.

    iow in all cases where Climate Temps are discussed (historical and present) it is AIR Temps only.

    Then maybe another dumb question: what public info data is there regarding average water temps in the oceans themselves? iow status or changes in the OHC, ocean heat content, i think it’s called. Is the research in this area still very limited, or are new things in the pipeline. THX

  17. 17
    Sean says:

    RE #15 #13, #3 quote from Glens supply chain url

    “Policies seeking to regulate emissions will affect not only the parties burning fuels but also those who extract fuels and consume products. No emissions exist in isolation, and everyone along the supply chain benefits from carbon-based fuels,” Davis said.

    This is of course the Elephant in the room of every international meeting about CC, CO2 targets, and ETS. They do not want to deal with it, and thus avoid reality and reason, and so all agreements are flawed.

    Australia is a good example, decreasing local manufacturing, increasing manufactured imports (eg China), already highest per capita GHG emissions, plus highest per capita exports of Carbon in Gas and Coal (eg to China). Both China and Australia are thus advantaged by avoiding this issue over the bulk of other nations, and neither wish to touch it with a ten foot pole. As Deep Throat wisely suggested to Woodward .. follow the money. :)

  18. 18
    David B. Benson says:

    Science in Ice: Lab Operates Inside a Glacier
    http://www.livescience.com/25931-lab-inside-glacier.html
    Glaciers (at least this one) don’t move quite the way previously thought.

  19. 19

    #16–Sean, it’s good to want to get clear on such issues. Short answer: in general, ocean surface temperatures are actual water temperatures in the surface layer of the ocean, not air temperatures. But it’s good to pay attention to the methodology used by each agency.

    For NOAA/NCDC, for example, the FAQs are here:

    http://www.ncdc.noaa.gov/cmb-faq/anomalies.php

    Point #3 deals with the data:

    Land surface temperatures are available from the Global Historical Climate Network-Monthly (GHCN-M). Sea surface temperatures are determined using the extended reconstructed sea surface temperature (ERSST) analysis. ERSST uses the most recently available International Comprehensive Ocean-Atmosphere Data Set (ICOADS) and statistical methods that allow stable reconstruction using sparse data. The monthly analysis begins January 1854, but due to very sparse data, no global averages are computed before 1880. With more observations after 1880, the signal is stronger and more consistent over time.

    What is “ERSST,” you ask? Well, luckily the acronym is hot-linked, so if you click on the original you get to this page:

    http://www.ncdc.noaa.gov/ersst/

    There are basically three versions of ERSST now; the latest is described here:

    http://www.ncdc.noaa.gov/ersst/papers/SEA.temps08.pdf

    (Be aware that this is not easy reading.)

    Bottom line is that for ERSST.v.3, you’ve got data from ships and buoys (just as in v.1 & v.2), plus satellite data as well.

    (Some limited use is also made of weather station data; but that’s mostly (if I’ve got this right) to help ‘see’ relatively short-term (“high-frequency”) warmings and coolings, and so is not that relevant for climate change.)

    ICOADS info is here:

    http://icoads.noaa.gov/products.html

    And note that it is seriously affected by budget cuts mandated by Congress:

    http://icoads.noaa.gov/ICOADS-notice.pdf

    Just part of the the “if we don’t know, then it isn’t real” approach favored by Tea Party types, I guess.

  20. 20
    Thomas says:

    sidd@12,
    I remember seeing that paper. I thought it a bit odd, they were measuring and increase in light transmitted into the water, but implying that reflected a significant loss of albedo. I was thinking, but isn’t the amount of sunlight that makes it through the ice into the water small enough that transmittance is a (very) poor proxy for albedo. But, I’m not in possession of any numbers.

  21. 21
    melty says:

    #7 Candide: “Seems that NASA doesn’t have the funding to do anything similar, and the old Aqua satellite was allowed to die with no replacement planned.”

    Rumors of Aqua’s demise may have been somewhat exaggerated. The AMSR-E instrument on Aqua failed in October 2011 — the other instruments on that Earth Observing System satellite are still functioning, AFAIK.

  22. 22
    sidd says:

    I see that one number in Pfeffer(2008) is superseded

    “…highest outlet glacier velocity observed anywhere [14.6 km/year (6)],…”

    Apparently JI hit 17 this year

    http://congrexprojects.com/docs/12c20_docs2/1-joughinesa.pdf?sfvrsn=2

    sidd

  23. 23
    Lawrence Coleman says:

    Welcome to 2013 Everybody! Just been reading an article by Coral Davenport in the National Journal re: putting money on adaptation measures now, rather than prevention. I couldn’t agree more!. Also looking at the usual ignorant comments posted at the forum at the bottom of the page. Siting that we are coming out of a little ice age..hence the warming and that it’s just the natural evolution of the climate etc. and that she’s pushing her own personal agenda by cashing in on the climate bandwagon. The denialists probably outnumber the people who ‘understand what’s going on’ by about 3-1. This is the the typical response by the public to these articles by what I’ve seen to date. Anyway she states that it’s too late aready to stop a 2C rise..fair enough! That it wont be until 2015 until the next round of talks and any laws or agreements that are passed wont need to be inacted for another 5 years after that. That President Obama can quite securely say that he has tried to do his best knowing full well that any proposed ammendments will be soundly defeated in the senate. Added to that the postponement of the double pike and somersaut off the fiscal cliff probably will spur a new spurt in growth in the industrialised countries with scant regard to the environment..up goes emissions..up,up and away! It now seems that Jim Hansen was too conservative himself when he pinned his flag to the benchmark 2C (400ppm) rise and in fact we probably have already zoomed past it years ago. The poles are melting just fine way below that mark. The jist of the article was that if we cannot make any headway in reducing emissions, let alone cutting emissions up to 2C we have virtually zero chance of achieving that after 2C and irreversable, uncontrollable and catastophic CC will enevitable follow. So c’mon guys take what we know out into the mainstream to counter the destructive lies by the denyalists with well thought out, factual and logical arguments. At work I’m known as Mr Climate Change and slowly but surely I’m turning my workmates uninformed veiwpoints around.

  24. 24
    Lawrence Coleman says:

    17 Sean: Yeah! I’m an australian and voted labor last election for the 1st time because I thought they had the best environmental policies..Boy! do I now feel cheated and betrayed. I still can’t vote Coalition because they still (apart from Mal Turnbull) don’t believe CC is happening. Labor knows it’s happening but they are firmly under the hold of big mining and oil. Rather frustating isn’t it!

  25. 25
    Patrick 027 says:

    re john byatt @ 358 (Dec.) – thanks.

  26. 26
    prokaryotes says:

    STORM – Development of a high resolution climate model
    Dr. Jin-Song von Storch, group leader in the department „The Ocean in the Earth System“ at Max Planck Institute for Meteorology (MPI-M), and her colleagues have accomplished for the first time an estimate of the Lorenz energy cycle for the world ocean with a one-tenth-degree ocean model developed within the STORM project. Such an estimate has not been possible with a state-of-the-art ocean model and enables more detailed studies on the sensitivity and stability of the Atlantic Meridional Overturning Circulation and more precise representations of climate and climate change.
    http://www.mpimet.mpg.de/en/communication/news/research-news-overview/storm-development-of-a-high-resolution-climate-model.html

    Arctic Storms: A Climate Danger Nobody’s Talking About

    Summer and fall are hurricane season, but for the storms known as polar lows, prime time falls in the dead of winter, when frigid air blows off sea ice to collide with warmer, moister air in the North Atlantic. Polar lows are a lot smaller and weaker than hurricanes, they’re generally shorter-lived, and the only danger they generally pose is to shipping and oil rigs.

    However, according to a new study in Nature Geoscience, the dozens of polar lows that roil the Greenland, Iceland and Norwegian seas every year may have an effect on the climate of North America and Europe. And if polar lows move northward with the changing climate, as some studies have predicted, winters in both places could become colder, even as the planet warms.

    As if that weren’t bad enough, a northward displacement of these Arctic storms could also raise sea level higher along America’s mid-Atlantic coast than the average increase of 3 feet or so projected for the world as a whole by 2100.

    It all has to do with the Atlantic meridional overturning circulation (AMOC), a vast conveyer belt of sea water that includes the Gulf Stream. http://www.climatecentral.org/news/arctic-storms-the-climate-danger-nobodys-talking-about-15363

  27. 27
    Hank Roberts says:

    Well, there’s a known unknown. From the Climatecentral link:

    “… what changes in polar lows might do to ocean temperatures … needs to be incorporated into climate models.
    But …. “It will probably take 10 or even 20 years before we have the raw computing power to do that,….”

    Maybe it’s time to turn some of those big Defense Department and petroleum-exploration computing systems over to the climatologists to hurry this along.

    [Response: It's one of my pet peeves that people say that something 'has to be incorporated into climate models' when it isn't new physics at all. Climate models all have low pressure storms in the Arctic - so you might claim that you need very high resolution to better capture the subtleties or the impacts on upper ocean mixing or something, but you can't claim they aren't included. All too common a trope unfortunately. - gavin]

  28. 28

    #27, Totally agree, its not a resolution problem it is rather a lack of integration or modelling the latest knowledge acquired. For instance the Europeans using refraction with ECMWF

    http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2321

    Using occultation from GPS Radio waves bending from many polar orbiting satellites to determine atmospheric densities. Damn good idea, simple enough and likely not requiring much greater computer capacity. However, I think we can use the sun (or other not so distant objects) optically in order to be vastly more precise, not using computers as much as telescopes, something to complement and check the models instantly. I know that GRIB can’t “see” or calculate some or most Arctic inversions, a key to understanding Arctic weather is routinely foregone. From there the computer long range forecast buildup of winter misses one of its biggest building blocks. In addition, I can easily say that I am completely puzzled by huge variations in sun disk dimensions in short time spans, when there seems to be no readily available explanations, I lack the understanding, just like models project without integrating or cross checking secondary observation sources, crucial in science, we estimate things without knowing all the mechanics. Like a car not quite tuned, a working vehicle nevertheless not as efficient as it can really be.

    But progress is being made, for those familiar with refraction occultation from satellites, we can use lower tropospheric data, they deal with the surface to air interface, the two combined explain a lot.

  29. 29

    I explain more about my #28 comment: http://eh2r.blogspot.ca/

  30. 30
    Hank Roberts says:

    > 27

    My ellipsis took out too much, Gavin — that reference was about incorporating the possible effect of possible changes in arctic storms on ocean circulation — not about incorporating arctic storms per se in climate models. It was an “if this, presumably that” kind of story — and may be more attributable to the newspaper editor than the scientist it got hung on.

    My bad, sorry.

    A bit better, but still an excerpt:

    “… if the ice migrates northward, these storms could migrate northward as well,” said co-author Ian Renfrew, of the University of East Anglia, in the U.K.
    If that happens, their … effect on the AMOC would diminish and the current would presumably slow….”

    [Response: I didn't mean to be overly critical, but these are processes which already happen in coupled GCMs - though the connections are more complex than the quoted 'presumption' would imply. The neat thing about the work being discussed is that ocean eddies are included, and it is conceivable that this will change the nature of the response to forcings in a coupled system..... or not. But it is the nature of the an intermediate step (however necessary and interesting) to not be able to predict the end point (otherwise it wouldn't be intermediate at all). - gavin]

  31. 31
    Hank Roberts says:

    and I munged that bit too; the quote ends at “as well”

  32. 32
    Tom R says:

    I have a question for the experts. I’m investigating the temperature record for my local area and I’m not sure what length of time to use for the average temperature baseline. I have 64 years worth of data and so far my baseline period has been from 1951 to 2010. I’ve used various periods and it can mean the difference between a positive and negative trend. It’s obviously critical to the results.

    Thanks for any help.

  33. 33

    #32–”I’ve used various periods and it can mean the difference between a positive and negative trend. It’s obviously critical to the results.”

    Maybe I’m misunderstanding you, Tom, but baseline should not affect trend, as I see it. The trend is a property of the period analyzed–say, 64 years–which is independent of your baseline value (say, 1951-2001.) (Absurd example: you could baseline not to a mean of any set of years, but to absolute zero if you wanted to.)

    But maybe you meant that the period analyzed affects the trend? (Certainly true.)

  34. 34
    Tom R says:

    Thanks for the reply Kevin.

    Clearly I didn’t think this through. I didn’t frame the question correctly in my statistically novice way. Baseline is probably the wrong term and my approach may be incorrect entirely.

    Here’s what I did.

    I wanted to see how the temperature has changed in my area over the years. So I calculated the average temperature for each year. Then I got the average temperature for the period 1951-2010 (60 years) as a “baseline” to derive the anomaly, i.e, the difference in the baseline average and the average for each year. I then plotted the anomaly vs 0 to see the points on a graph. Then I used a simple linear regression to determine trends.

    My problem was that any period I used to calculate the baseline average temperature would be slightly different meaning a different anomaly.

    I see now that what I called the baseline (avg temp for period) has no effect on the trend but the starting and ending points for the trend does.

    Maybe that would have been the better question. I chose two 30 year periods to determine trends. One from 1951-1980 and the other 1981-2010.

    Sorry for the confusion. Doesn’t matter anyway I guess. Very poor linear correlation.

    Here’s a link to the chart if you’re interested.

    http://imageshack.us/photo/my-images/542/poranomalytrends.png

  35. 35
    prokaryotes says:

    Slip Slidin’ Away – Ice sheets and sea level in a warming world ABRUPT SLR (IN METERS) A LIKELIHOOD http://climatestate.com/climate-state/videos/item/slip-slidin-away-ice-sheets-and-sea-level-in-a-warming-world.html

    New lecture video with Richard Alley

  36. 36
    Hank Roberts says:

    For Tom R.: the discussion here explains the terms and choices:
    http://www.woodfortrees.org/notes#wti

  37. 37
    Guy Walton says:

    “The Climate Guy” would like you to check out his latest post on weather.com at:
    http://www.weather.com/news/climate-lottery-december-20121212

    Please play “The Climate Lottery” and follow how our warming world is affecting the United States on a seasonal basis.

    Cheers!

  38. 38
    sidd says:

    Mr prokaryotes: Thank you for the link to the Alley video.
    One more pinning point under Thwaites b4 WAIS is gone is my takeaway. Glad he has the Pollard ref in there.

    sidd

  39. 39
    vukcevic says:

    OT
    Today is 70th anniversary of death of Nikola Tesla, one of the world’s greatest inventors http://www.teslasociety.ch/info/ton/Fiorello_La_Guardia_uber_Tesla.wma

  40. 40
    Ray Ladbury says:

    Tom R.
    Looks to me as if you are getting a best fit ~0.0225 degrees per year–which is well in line with the global average. I do not understand your frustration?

  41. 41
    Hank Roberts says:

    > Alley video
    That is a good one, well worth 45 minutes to watch.

  42. 42
    prokaryotes says:

    What i find very worrying from the infos here is the mentioning of possible volcano’s beneath Greenland and Antarctica. Imagine we have somewhere a slip and one of the volcano’s wakes up. This could mean a potential feedback to accelerate ice mass lose more inland.

    [Response: this is not something that is very likely to happen. Volcanoes under ice (as in Iceland) have big local effects, but are trivial across the whole ice sheet. - gavin]

  43. 43
    Tom R says:

    Ray, because I was looking at local average highs, lows, extremes and so forth my units are Fahrenheit, so the 1981-2010 trend is about .0123 C for my area. When I run the global land data from NCDC for the same 30 year period I get 0.030 C. R^2 for that trend is 0.735 globally while locally it’s .0334. Solid linear correlation for the former but very poor for the latter.

    So it’s not so much frustration as it is confusion. But, if I understand it correctly, most of the warming is being driven by higher latitudes so my trend for 36 north may be about what was expected despite the lack of correlation.

    Thank guys.

  44. 44
    Russell says:

    Those wishing to congratulate the Editors should note that National Review‘s Planet Gore blog is entering its second decade of publication

  45. 45
    perwis says:

    New paper from the Ice2sea project on expert judgments on future contributions from Greenland and Antarctica to sea level rise:

    J. L. Bamber, W. P. Aspinall. An expert judgement assessment of future sea level rise from the ice sheets. Nature Climate Change, 2013; DOI: 10.1038/nclimate1778

    Summary here: http://www.sciencedaily.com/releases/2013/01/130106145743.htm

    I have not yet been able to read the paper, but I understand it is based on a questionnaire to glaciologists and other experts. The statistical analysis of the replies yields a contribution from ice sheets in year 2100 of +29 cm (median) to +84 cm (95% percentile).

    For a plausible “high end” scenario in 2100 add ca +50 cm for thermal expansion and +20 cm for small glaciers (see Table 1 in Katsman et al 2011).

    The projection of +84 cm from ice sheets in 2100 is more than the Netherlands-based expert assessment (Katsman et al 2011) with +63cm, but less than Pfeffer et al (2008) with +116 cm.

    Prokaroyotes: Thanks for the Richard B. Alley video! Here is a recent popular essay by him: http://geosociety.wordpress.com/2013/01/02/warming-up-to-scott-a-first-glance-at-controls-on-glaciers/

  46. 46
    sidd says:

    Where is the estmate of 116cm from Pfeffer (2008) ? i am looking at table 3 in that paper, but i dont see the numbers add up to 116 cm in any one of his 3 scenarios. The numbers there for the low-1, low-2, hi scenarios are respectively

    GRIS 165,165,538
    AIS 146,128,619
    GIC 174,240,551
    Thermal expansion 300,300,300
    total SLR 785,833,2008

    in mm

    sidd

  47. 47
    sidd says:

    I realize after some arithmetic that the 116cm estimate attributed to Pfeffer comes frm the High Scenario for GRIS and AIS

    sidd

  48. 48
    prokaryotes says:

    I found a bit more about WAIS and volcanoes

    “This eruption occurred close to Pine Island Glacier on the West Antarctic Ice Sheet. The flow of this glacier towards the coast has speeded up in recent decades and it may be possible that heat from the volcano has caused some of that acceleration. However, it cannot explain the more widespread thinning of West Antarctic glaciers that together are contributing nearly 0.2mm per year to sea-level rise. This wider change most probably has its origin in warming ocean waters.”

    Volcanoes are an important component of the Antarctic region. They formed in diverse tectonic settings, mainly as a result of mantle plumes acting on the stationary Antarctic plate. The region also includes amongst the world’s best examples of a long-lived continental margin arc (Antarctic Peninsula), a very young marginal basin (Bransfield Strait) and an oceanic island arc (South Sandwich Islands). Many extinct volcanoes are very well preserved and others are still active (e.g. Deception Island, Mount Erebus, and the South Sandwich Islands). Volcanic eruptions were common during the past 25 million years, and coincided with the great period of climatic deterioration that resulted in the formation of the Antarctic ice sheet. Many of the volcanoes show the effects of interaction with ice. BAS has played a major role in describing these effects and modelling their influences on the resulting volcanic sequences. It is important to describe and understand these interactions in geologically recent times in order to predict future configurations of the ice sheet and its role in the global system. http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=341

    Melting ice caps may trigger more volcanic eruptions

    The shifting stress might even cause eruptions in unexpected places. “We think that during the Gjàlp eruption, magma reached the surface at an unusual location, mid-way between two volcanoes, because of these stress changes,” says Pagli. McGuire thinks the Vatnajökull study is based on “perfectly reasonable” physics. However, he says that climate change presents an even more explosive threat. “It’s not just unloading the crust that triggers volcanic activity but loading as well.”

    He and his team are looking into the effects that rising sea-levels – also a consequence of melting ice caps – will have on volcanoes. “We are going to see a massive increase in volcanic activity globally,” he told New Scientist. “If we look back at previous warm periods, that is what happened.”
    http://www.newscientist.com/article/dn13583-melting-ice-caps-may-trigger-more-volcanic-eruptions.html

  49. 49
    wili says:

    New Hansen article coming out soon:

    “Sea level rise could lead to a cooler, stormier world

    A catastrophic rise in sea level before the end of the century could have a hitherto-unforeseen side effect. Melting icebergs might cool the seas around Greenland and Antarctica so much that the average surface temperature of the entire planet falls by a few degrees, according to unpublished work by climate scientist James Hansen of NASA’s Goddard Institute for Space Studies in New York City.

    While it might sound welcome, the temperature differences produced by the “iceberg cooling effect” could lead to even more climate chaos in a world already devastated by extreme weather. Winter storms, for instance, are powered by the temperature differences between the poles and the equator, so there might be storms of unprecedented ferocity.

    Most other climate scientists think the ice sheets will only melt slowly, largely because this is what happened at the end of past ice ages. Hansen, however, thinks this logic is flawed. The reason that sea level only rose slowly in the past, he writes, is because the planet only warmed slowly. After the last ice age, for instance, it took 10,000 years for the average global temperature to rise around 4 °C. Now the world is on course to warm this much in less than 200 years.”

    http://www.newscientist.com/article/dn23048-sea-level-rise-could-lead-to-a-cooler-stormier-world.html

    Do we wait till the whole article comes out, or can we discuss what is presented here?

    I am curious as to whether the scenario presented in the second paragraph seems plausible to people here. It seem counter-intuitive to me, but lots of things in physics are that way. Could enough icebergs really calve off fast enough to have that kind of global cooling effect? In principle, I guess if you could immediately pulverize the ice in the ice sheets and spread it around the oceans, a lot more cold mass would be exposed to the water and air than is there is now exposed in it’s ice-sheet state. But is still is hard for me to wrap my mind around the magnitude of the claim.

  50. 50
    Ray Ladbury says:

    Tom R.,
    Well, would you not expect weather to dominate more locally than globally? Again, your results are not that far off. Remember we are looking for a relatively small but consistent trend in a very noisy dataset. The noise is weather. The trend is warming.


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