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Unforced Variations; June 2012

Filed under: — group @ 1 June 2012

This month’s open thread…


408 Responses to “Unforced Variations; June 2012”

  1. 51
    Hank Roberts says:

    Wow. For those who don’t remember why we have a Clean Air Act, and for those who may be wondering why it’s taking so long to update those old laws:

    http://www.spc.noaa.gov/publications/corfidi/haze.html

    Haze Over the Central and Eastern United States
    Stephen F. Corfidi
    NOAA/NWS Storm Prediction Center
    Norman, OK 73072
    Mar. 1996; Updated Dec. 2004, Feb. 2009, and Jan. 2012

  2. 52
    vukcevic says:

    @ #49 Unsettled Scientist 5 Jun 2012 at 2:32 PM
    I have added details and a quote on the webpage:
    http://www.vukcevic.talktalk.net/00f.htm

  3. 53
    Susan Anderson says:

    Those who believe that somehow sulfur dioxide will do us a world of good seem to have forgotten a whole lot of history and science. We are at quite a different level than we were in the mid 1900s. At this point, multiple forms of pollution and multiple consequences are assailing us all over the globe. The idea that a limited fix would somehow reestablish polar freezing and allow us all a breather is pure dreaming.

    It is particularly distressing to see real experts whose knowledge and hearts are solid getting so desperate they appear to be forgetting their own science.

    Whatever might be the solution, I cannot believe increasing sulfur will do anything but contribute to our continuing air and water problems, including but not limited to ocean acidification.

  4. 54
    Susan Anderson says:

    Aaron Lewis and Brian Dodge @~48,49

    Thank you for knowledgeable queries and information
    BP WHOI FOIA – an alphabet soup of corruption

    [Response: Note that the BP request is under discovery, not FOIA. Wholly different legal basis, and it does not place the materials in the public domain. - gavin]

    Lewis comment about Arctic as a source of water vapor will, I hope, be addressed by those more knowledgeable than I. It makes sense to me, but I’m an unscientific water vapor animation addict; certainly there is an increase in both activity and level over the last few years:
    http://weather.unisys.com/satellite/sat_wv_hem_loop-12.gif
    http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/wv_nhem_anim.gif
    (yes, it would be lovely if the latter could be slowed down but the north pole center is valuable)

  5. 55
    Susan Anderson says:

    Thanks for the clarification. Discovery is just as (or more) time-consuming and intrusive, but indeed a different process and not in the public domain.
    – change subject:
    Just opening my weekly Earth Observatory summary, and this is beautifully done and only a minute and a half long; please watch the video!

    http://earthobservatory.nasa.gov/blogs/earthmatters/2012/06/04/i-can-see-my-home-from-here-landsat-contest/?src=eoa-blogs

  6. 56
    Anteros says:

    Paging Louise -

    In case you haven’t found good cause to re-visit either Lucia’s site or Climate Etc, here are the two graphs you asked me to show you -

    Please show me the datasets that show global cooling and you can then give up wondering what I’ll say.

    http://www.woodfortrees.org/plot/rss/from:1997.25/to:2012.25/plot/rss/from:1997.25/to:2012.25/trend

    http://www.woodfortrees.org/plot/hadcrut3vgl/from:1997.25/to:2012.25/plot/hadcrut3vgl/from:1997.25/to:2012.25/trend

    Two lovely graphs of a 15 year cooling trend just for the price of your thoughts – surely a veritable climate-bargain! :)

  7. 57
    Unsettled Scientist says:

    >vukcevic @52, it seems you are still confusing the 1960s with 1971, which is the year that Washington Post article mentioned on your page was published. So I will take that as a yes, “analysis” is in quotes because it is sloppy work.

    For the rest of us, I would simply direct you to a post on this site. It will serve to illuminate the issue better than that link above will.

    http://www.realclimate.org/index.php/archives/2005/01/the-global-cooling-myth/

  8. 58
    MARodger says:

    DP @50
    You say “…Northern Hemishere snow cover could hit a record low this June.” To add a bit more.
    Simply the snow cover has been meltng away quicker & quicker over the last few decades & now it will be melting away down to its ‘minimum’ during June rather than July.

    Minimum NH land snow cover occurs in September (as per Arctic Sea Ice) with the minimum of a couple of million sq km of difficult-to-melt snow remaining each year. Since the records began (Rulgers from 1966 with a few early gaps), August snow cover was pretty much at the same level as September. July has been slowly dropping down to approach that same level in the last few years.
    Now its June’s turn to start its drop. It has a bigger drop to make & as June is also the month of maximum insolation, the reduction of albedo in northern climes has added significance.

    See graph two click down this link.

  9. 59
    Susan Anderson says:

    Anteros:

    What a bore. Take a look -
    http://www.skepticalscience.com/graphics.php?g=47

    When we have context, it is dishonest to leave it out.

  10. 60
    Susan Anderson says:

    Brian Dodge posted a link to a statement from WHOI, and at the risk of boring on and bringing coals to Newcastle, it’s worth more of a look. I would add that it should no longer be possible to regard the proliferation of time-consuming provocation as in any way innocent. Some extracts here, full statement at:
    http://www.whoi.edu/main/president-director/statement/scientific-deliberative-process

    This case raises issues that go far beyond our institution and BP. Despite earlier Supreme Court recognition of the importance of the deliberative scientific process, there remains inadequate legislation and legal precedent to shield researchers and institutions who are not parties to litigation from having to surrender pre-publication materials, including deliberative emails and notes, manuscript drafts, reviewers’ comments, and other private correspondence. This situation leaves scientists and institutions vulnerable to litigants who could disregard context and use the material inappropriately and inaccurately in an effort to discredit their work. In addition, there is no guarantee that the costs, both time and material, incurred by an institution in response to court-mandated requests will be reimbursed by the litigants.

    …. threatens to facilitate misinterpretation of scientific findings by highlighting preliminary evaluations and opinions, conflating facts with assumptions, and implying conclusions without a valid scientific process or review. …. researchers and their institutions may reasonably fear that their deliberative process can be attacked and their intellectual property exposed, or that they will become entrained in litigation to which they are not parties and where they are unlikely to derive any benefit. As a consequence, scientists may feel forced to curtail, censor or avoid the normal deliberative process. In future … researchers may be more reluctant to volunteer expertise and technology.

    …. It is unlikely that institutions such as WHOI would be able to identify or prosecute this infringement of intellectual property rights.

    …. some of these very qualities that drew scientists into the response effort will suffer as the deliberative process is eroded.

  11. 61
    Dan H. says:

    MA and DP,
    Yes, the snowpack has started its melt earlier in recent years as evident by the Rutgers data. This has resulted in neither a change in the annual minimum, nor annual maximum (see link winter, spring and fall data). The timing of the melt may have implications in agriculture, flood control, and winter sports (last year, many of the Colorado ski resorts had special July 4th celebrations due to the late snowmelt, which also resulted in later year flooding of the Missouri River).

    http://climate.rutgers.edu/snowcover/chart_seasonal.php?ui_set=nhland&ui_season=4

    This earlier paper shows that the greatest change in spring melt has occurred in central Canada, from the Rockies to the Great Lakes.

    http://www.mendeley.com/research/spatial-variability-trends-observed-snow-depth-north-america-1/

    A few papers have linked Eurasian snow extent to summer temperatures and rainfall in Asia. A lesser inverse link was found between North American snow cover and monsoons. A suggested difference is the larger oceanic influence in Norht America compared to Eurasia.

    http://www.iges.org/people/Shukla's%20Articles/1999/Relation%20Snow%20Cover.pdf

    http://journals.ametsoc.org/doi/abs/10.1175/JCLI4068.1

    Remember, the snow extent does not necessarily relate to snow depths, as evident from this paper.

    http://water.columbia.edu/files/2011/11/Gong2008Observed.pdf

  12. 62
    flxible says:

    Anteros @56 takes cherry picking to the next level . . . remove the ‘point25′ from the dates and watch the “15 year cooling trend” magically revert to the real worlds warming trend. Is Anteros the “avenger of unrequited love” for the denialators?

  13. 63
    Anteros says:

    Susan Anderson -

    When we have context, it is dishonest to leave it out

    It seems to me you may have let a prejudice get in the way of an accurate assessment of my comment.

    There seemed no need for me to state the obvious – which is (to me) that the 15 years of ‘cooling’ (in just two sets of data) mean, signify, or are evidence for virtually nothing, except the sound of noise.

    You’ll notice that I made not the slightest mention of such things – so it seems to me you merely assumed them.

    The context – if you really must know – is that last year I asked Louise (out of interest, and in its own context) this question – “what would you say when two sets of data show 15 years of cooling this coming spring?” Louise said she’d get back to me…

    Well, I’d forgotten about it until a few days ago when Louise appeared on two separate blogs crowing about how there were no data sets showing 15 years of cooling etc etc. So, to find out what she would actually say I presented her with the appropriate graphs.

    I think it is relevant and pertinent – for all of us – to answer the same question. Indeed, I think the SkS escalator is one very good interpretation (even if it is expressed in confrontational and partisan language) and it also happens to be close to my own..

    I’m sorry you find the neutral offerings of two graphs as a ‘bore’, but having said that I’d rather not have the accusations of dishonesty, especially when they are founded on nothing but unwarranted supposition.

    FWIW, I’m on record as predicting next year as the ‘hottest ever’ – also without any intended implied meaning. It is simply what I expect.

  14. 64
    Susan Anderson says:

    Anteros, humble apologies … my bad.

  15. 65
    Ray Ladbury says:

    Anteros,
    A couple of things. First, starting with an El Nino and ending just as we are leaving a La Nina is certainly cherrypicking. Second, if you use HADCRUT4, even then the trend is positive. Third, RSS (and UAH) for that matter tend to be overly influenced by ENSO, so any effect of ENSO is going to be greatly exaggerated.

    Fourth… yawn!

  16. 66
    Hank Roberts says:

    Anteros, you should review your part in the thread “bickmore-on-the-wsj-response” where you pointed to charts and made claims that people found were mistaken.

    You are pointing to and interpreting part of what’s available and doing that incorrectly.

    Do you remember how many years of that data set are needed to claim whether or not a detectable trend exists?

    Do you remember how if you pick sufficiently long time spans to do the statistical calculation, it’s possible to say there’s a trend?

    Do you remember that if you pick stretches too short to be valid, you can get the “escalator” result Susan points out, and mistakenly claim cooling?

  17. 67
    Steve Fish says:

    Re- Comment by Anteros — 6 Jun 2012 @ 8:50 AM:

    Your response to Susan is disingenuous. Why were you responding to someone here who had posted elsewhere? With no context!

    Steve

  18. 68
    Jason says:

    It’s good to see other websites posting good information about the environment and how we can work to change our negative environmental impact as a modern society. I recently posted a story to my blog (thenewsmovement.com) that concludes Earth is headed for an Apocalypse of sorts if we don’t get our act together!

    Come on people, let’s get with it and do something!

  19. 69
    grypo says:

    The Pacific Institute is pleased to welcome Dr. Peter Gleick back to his position as president of the Institute. An independent review conducted by outside counsel on behalf of the Institute has supported what Dr. Gleick has stated publicly regarding his interaction with the Heartland Institute. This independent investigation has further confirmed and the Pacific Institute is satisfied that none of its staff knew of or was involved in any way.

    http://www.pacinst.org/press_center/press_releases/statement6612.html

  20. 70
    David B. Benson says:

    Arctic Ice Melt Is Setting Stage for Severe Winters
    http://www.sciencedaily.com/releases/2012/06/120606132420.htm
    Better prepare.

  21. 71
    Dan H. says:

    David,
    Furthering the theory, it has been postulated that the Arctic warms until it is completley ice free, allowing much greater evaporation of the polar waters, leading to a succession of severe winters, triggering another ice age. The extent of glaciations reduces evaporation, gradually leading to a reduction in winter snowfall, and a retreat of the glaciers.

  22. 72
    J Bowers says:

    Anteros — “Two lovely graphs of a 15 year cooling trend just for the price of your thoughts – surely a veritable climate-bargain! :)”

    Paging Anteros, see what happens when you change the dates to 1996 to 2011: Two lovely graphs of a 15 year warming trend.

  23. 73

    71, Dan H,

    I’m afraid you’ve completely misunderstood (or failed to read) the link.

    The theory has to do with the redistribution of heat (or cold) from north to south, a result of climate change, not a cause of it.

    Your own theory about evaporation (a supporting link would be nice, or is that an “it has been postulated by me” instance?) similarly would not warm or cool the climate, but instead simply result in vertical energy transport.

    I find it very hard to believe that increased evaporation due to warmer temperatures in the Arctic would “trigger another ice age.”

    Come on. Really?

  24. 74
    Hank Roberts says:

    “Pierre Deschamps and colleagues now report the results of a major coral-drilling programme in Tahiti, and establish that meltwater pulse 1A took place between 14,650 and 14,310 years ago, coincident with a warming spike. Sea levels rose by between 14 and 18 metres. Such a large rise suggests that ice-sheet collapse in Antarctica may have contributed to these changes, previously a point of much contention.”
    http://www.nature.com/nature/journal/v483/n7391/full/nature10902.html?WT.ec_id=NATURE-20120329

  25. 75
    Unsettled Scientist says:

    A few months ago I took my mother to the doctor, and apparently she and he share a love of gardening. They were discussing certain flowers which were blooming very early. IIRC this was in February. It seems very straightforward: early warmth brings early blooms. But some flowers don’t respond to the early Spring, or even bloom late. Why do they do this? Interestingly it appears these other plants are taking their cues not from the timing and magnitude of Spring temps, but rather from the previous Autumn. Initially this surprised me but then I remembered that there are some plants that require a certain number of days that are cold enough to even flower at all the next year.

    http://www.sciencenews.org/view/generic/id/340952/title/Delay_of_bloom_blamed_on_climate_change

  26. 76
    flxible says:

    Unsettled – speaking from experience, I’d add that the winter temperatures are as, or more important, than the fall onset. The cold season length can be short if the low temperatures are low enough. Here on Vancouver Island warmer winters result in light fruit bloom and trees that throw additional bloom in the fall when night temps start to drop again, giving those particular buds the additional chill time they missed last winter, short stretches of intense cold act the same as long stretches of “mild” cold . . . very troubling re future fruit production as the climate changes.

  27. 77
    Susan Anderson says:

    Anteros,

    Now it’s your turn to apologize for framing your response deceptively. It appears you are *not* honestly concerned about these issues, only interested in demonstrating your false premise.

    I’m getting really tired of accusations that reverse the truth of the supposed “debate”. On one side are almost all the facts, and on the other is a whole lot of hot air, masquerading in some cases as a concern for civility.

    The evolving history of violence is frightening, and it appears those trying to incite the violence are very busy getting out in front and accusing their potential and actual victims of intending mayhem.

    I don’t think exploiting fear, rage, and the rest while claiming hostilities are being initiated by the victims is a good way to solve problems which affect not only future generations, but at this point, our all too current situation.

  28. 78
    David B. Benson says:

    Dan H. @51 — Not possible.

  29. 79
    dbostrom says:

    More news on the Homo Bolidus impact event:

    Earth may be near tipping point, scientists warn

    Source article forthcoming in Friday edition of Nature.

  30. 80
    Guy Rowland says:

    Hi all – as many of you know, there’s an awful lot of the “no cooling since 199x” meme flying around these days. Clearly that’s not a tenable position, so under pressure this then gives rise to the next meme – “the warming, overall, is too small to worry about”. So a few questions arising from that proposition:

    1 – is it accurate to say that average decadal temperature rise since 1980 is between 0.15 and 0.2 degrees?

    2 – Since a 1.5 degree rise over a century is lower than most projections, is it thought that the temperature will FURTHER rise either from heat from the oceans, positive feedbacks etc? (references too if pos, thanks).

    3 – Is it bad enough even at 1.5 degrees? What’s the latest on attribution for extreme weather events? I see there’s work ongoing here – http://www.wcrp-climate.org/conference2011/documents/Stott.pdf – just wondering if I’d missed anything.

    Thanks all.

  31. 81
    Dan H. says:

    Sphaerica,
    Really. Just because you are unfamiliar with something does not mean it does not exist. I am referring to the old Ewing Donn hypothesis. Here is a new take on this age old theory.

    http://www1.umn.edu/news/news-releases/2002/UR_RELEASE_MIG_166.html

    [Response: Just because a theory exists doesn't mean it has any credibility. - gavin]

  32. 82
    Lawrence Coleman says:

    Just wondering how many of you would consider that the current rate of ice albedo in the arctic constitutes a breached tipping point? If not what are the signs and symptoms of this tipping point being breached? How do we know when it’s too late? We currently have a severely impared balance mechanism about to go into oscillation as far as I can make out. The summers are longer and hotter, thus more ice melts, consequently the winters are shorter and warmer so not as much ice forms or at least not to the usual quality since midway through the pliocene. The relentless ice melt has been quite predictable now for at least the past 10 years. The arctic oceans are progressively becoming warmer and causes great additional forcing onto the failing system. I’m trying not to ignore the elephant in the room here which many of you seem to be doing by my observations. I’m guessing that we are already witnessing probably the planet’s most important and influential tipping point well into the process of being breached.
    What do you think?

  33. 83
    Brian Dodge says:

    “…it has been postulated that the Arctic warms until it is completley ice free, allowing much greater evaporation of the polar waters, leading to a succession of severe winters, triggering another ice age.”

    What I have seen postulated (e.g. here) is that the closing of the Isthmus of Panama altered the Atlantic circulation. The Antarctic Circumpolar vortex drives surface water north via Eckman transport, and the only place for the water to go after the Isthmus closed is into a newly formed Gulf Stream.*

    This is where the evaporation which allows the formation of continental ice sheets (by Milankovic driven albedo feedback) originates. The warm salty surface water is cooled and made saltier by evaporation, and when it get far enough north that the increase in density cause the water to sink, thermohaline circulation adds to the wind driven Atlantic Meridional Overturning Circulation.

    And if the Arctic became ice free during interglacials, there would be a record in the Lomonosov Ridge sediment record.
    “Recently, a few coccoliths have been reported from late Pliocene and Pleistocene central Arctic sediment (Worsley and Herman, 1980). Although this is interpreted to indicate episodic ice-free conditions for the central Arctic, the occurrence of ice-rafted debris with the sparse coccoliths is more easily interpreted to represent transportation of coccoliths from ice-free continental seas marginal to the central Arctic. The sediment record as well as theoretical considerations make strong argument against alternating ice-covered and ice-free conditions (Donn and Shaw, 1966; Clark et al., 1980). Although the time of development of the pack ice for the central Arctic Ocean is unknown, to date there is no evidence that precludes a Miocene origin.” http://www.nap.edu/openbook.php?record_id=11798&page=137 And some probably originate in the open water of polynyas, but this represents a small area compared to the amount of ice free Arctic surface seen in the last decade.

    *Warm water is piled up in the Gulf of Mexico by the equatorial trade winds, instead of exiting through the former “straights of Panama”. Geostrophic flow around the North Atlantic gyre pushes it north along the east US coast. ThermoHaline Circulation returns the water south as a bottom current(less what has evaporated but with all the salt), and much of the bottom water spreads east into the Pacific through the wide gap between Africa and Antarctica. http://hermes.mbl.edu/news/press_releases/images/thermohaline_circulation.jpg
    The closure also caused reversal of current through the Bering Straight, bringing warmer Pacific water further north. http://geology.gsapubs.org/content/28/6/551.abstract

    PS – shoot down the bad ideas, not the messenger.
    PPS – reCaptcha says “hottest fusiform”

  34. 84
    Ray Ladbury says:

    Guy Rowland,
    Ultimately, the amount of warming is determined by what temperature must be reached to restore radiative equilibrium at the top of the atmosphere, while what we care about is the change in surface temperature. What is more, we are not talking about a single-solid sphere, but rather multiple, interconnected temperature reserviors–the atmosphere, the shallow ocean, the deep ocean. So, while we are seeing moderate warming now, there could be more “in the pipeline” as the effects of greenhouse gas absorption continue to increase.

    This is a trick denialists play often–they know if they assume the planet returns to equilibrium rapidly, they get a low sensitivity. However, if you take actual physics into account, you see that such rapid return to equilibrium is not possible. The atmosphere does interact with the shallow ocean, which interacts with the deep ocean–on timescales of decades, perhaps centuries in come cases. What is more, some feedbacks evolve quite slowly. So the current rate of warming of 1.5-2 degrees per century is likely the tip of the melting iceberg.

    Tamino has developed a very instructive 2-box model of the climate–one box representing the atmosphere, which nears equilibrium on a timescale of about a year, and the other representing the oceans with a timescale of about 30 years. He gets pretty good agreement with this model. Check out Open Mind and the Open Mind archives at Skepticalscience.

  35. 85
    Dan H. says:

    Guy,
    1. The average GISS temp rise since 1980 is 0.16 C/decade, while CRU is 0.15, and UAH is 0.14. So, the low end of your range has been observed. The rise has not been steady, with the middle decade showing the highest rise; all three data sets show a rise of ~0.4 C/decade between 1992 and 2002. These are all higher than longer term trnds (60+ years), so a slowdown in recent years was not unexpected.

    2. Predictions are all over the map here, and constantly being modified with new estimates due to solar, cloud, albedo changes, etc.

    3. Obviously, 1.5 is not as bad as 2, but worse than 1. The greatest effect would be felt in the Arctic, with the least experienced in the tropics. Extreme weather events are still uncertain, as higher water vapor leads to greater precipitation events, but the lessened temperature gradient is expect to lead to a reduction. The main question is how the atmospheric circulation would change with respect to NAO, AO, PDO, and ENSO.

  36. 86
    Steve Fish says:

    Re- Comment by Dan H. — 8 Jun 2012 @ 5:36 AM:

    If your ice age theory is “age old,” then you should be able to supply several references to peer reviewed research about it. So far, you can’t even claim that it is new age blather because you have only provided a link to a news item. Until you provide appropriate science to support your assertions, you should not complain when people don’t take you seriously.

    Steve

  37. 87
    Hank Roberts says:

    2002 isn’t new, and that link’s not to a paper.

    Ewing and Donn’s theory is mentioned twice in this book:

    Fixing Climate: The Story of Climate Science – And How to Stop Global Warming
    By Robert Kunzig, Wallace S. Broecker
    http://books.google.com/books?id=q4PrZTHtx_UC

    “… unfortunately for the Ewing-Donn theory, however, which is now generally disregarded, the evidence from Arctic sediments indicates ….”

    and

    “Maurice Ewing and William Donn were pushing a theory that placed the cyclic mechanism entirely within the Arctic Ocean, rather than in outer space ….”

    http://scholar.google.com/scholar?as_ylo=2008&q=%22Ewing%22+%22Donn%22++arctic+cycle&hl=en&as_sdt=1,5&as_vis=1

  38. 88
    Guy Rowland says:

    Thank you very much Ray and Dan, very helpful. Tamino’s excellent post here – http://tamino.wordpress.com/2011/01/20/how-fast-is-earth-warming/ – left me wanting more. He concludes: “To answer the question posed in the title of this post: presently, Earth is warming at about 1.7 deg.C per century. There’s good reason to believe that it’ll be warming even faster in the upcoming decades”. I’d love some more info on this, which was beyond anything my search found – all pointers and references gratefully received.

  39. 89
    Ray Ladbury says:

    Dan H.: “. Predictions are all over the map here…”

    Actually, no they aren’t. The midrange remains 3 degrees per doubling, with steadily decreasing uncertainty on either end of the 90% CL.

  40. 90
    Hank Roberts says:

    for Guy Rowland, a quick search limited by site is often useful, e.g.:
    https://duckduckgo.com/?q=site%3Aipcc.ch+warming+rate+change

  41. 91
    Hank Roberts says:

    > Dan H…..
    > data sets show a rise of ~0.4 C/decade between 1992 and 2002

    New readers–don’t trust claims posted in comments by unidentified people at RC; often they’re unsupported. Check every claim.

    How many years of data are needed to detect a trend in any particular data set?

    This will help:
    https://tamino.wordpress.com/2011/11/07/berkeley-and-the-long-term-trend/

  42. 92
    Unsettled Scientist says:

    Steve Fish @ 86, it’s even worse. Dan H’s link doesn’t even mention Ewing-Donn. That guy does very little to provide illumination, but certainly does much to provide confusion. This is, of course, his goal. “Oh, you’ve never heard of Ewing-Donn? Well read this which discusses something different.” Some of us are trying to learn the current consensus science, Dan H. is trying to make that harder for us.

  43. 93
    Dan H. says:

    Steve,
    It is neither my ice age theory, nor do I support it. I was merely responding to David’s post about less ice leading to more severe winters. The premise had been around for quite some time, of which many here were apparently unaware. Some people are way to picky/insecure, that they demand a link to everything imaginable, which is difficult for work half a century old. Some people even think that this will lead to confusion among the gullible. What is science, but the postulation of new theories, and then research to prove or disprove them. If we just sat around, content with all the old answers, we never progress.

    The premise that a melting Arctic will lead to more severe wintes is nothing new.

  44. 94
    Dan H. says:

    Guy,
    The Earth has warmed ~0.8C over the past 130 years (equating to ~0.6C/century). All of that (and more) occurred over the four decades of the 1920, 30s, 90s, ans 2000s. The remaining decades exhibited cooling or stagnant temperatures, as seen here:

    http://woodfortrees.org/plot/hadcrut3vgl

    There are those who claim that temperatures will rise more rapidly this century than last, resulting in greater than 1C temperature rise by 2100. Forward predictions demand on various assumptions; including atmospheric CO2 and aerosol levels, solar output, clouds and oceanic responses.

  45. 95
    Guy Rowland says:

    Thanks Hank @90 – that’s where I’m still a little confused though. The first article referenced there – http://www.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-projections-of.html – shows the familiar different projections. However, only A2 shows a rate of increase in the warming, the others look (to my untrained eye) linear, eventually tailing off in the 2nd half of the century. Also, in this 2007 report, they say observed warming is 0.2 degrees, whereas it is now revised to 0.17 degrees – a fraction lower. Still within range, but at the lower end of projections.

    I might have this completely wrong, but is it the case that our emissions thus far are closest to the A1 scanerio? If so, I’m still struggling to see research that suggests that the rate of warming will likely increase, as suggested by Tamino, beyond the slightly vague notions of possible positive feedbacks. I’m just checking I have that right, or if there’s something I’ve missed. Once again thanks for all help.

  46. 96
    Hank Roberts says:

    try this:
    http://www.nature.com/nclimate/journal/v2/n4/full/nclimate1385.html

    Global warming under old and new scenarios using IPCC climate sensitivity range estimates

    Joeri Rogelj, Malte Meinshausen & Reto Knutti

    Nature Climate Change 2, 248–253 (2012)
    doi:10.1038/nclimate1385

    Published online 05 February 2012

  47. 97
    Steve Fish says:

    Re- Comment by Dan H. — 8 Jun 2012 @ 12:45 PM:

    New hypotheses are suggested in science all the time and if they have any worth they are studied by scientists. A 50 year old hypothesis should be in the literature if it explained anything useful and you should be able to find it or subsequent research on it.

    Asking for references is a standard part of the scientific process, not due to being “picky/insecure.” This is especially the case when someone, such as yourself, makes a habit of making off the wall statements, like your ice age comment, without reference, and who often provides references that do not support their contentions. This disingenuous behavior is also the method used by denialists and the agencies that denialists often work for in order to of fool individuals who are not familiar with the literature being discussed. Why don’t you change your ways?

    Steve

  48. 98
    Hank Roberts says:

    PS for Guy — always look at authors’ home pages for material that may otherwise be paywalled, or for variants that are free to read. Knutti’s:
    http://www.iac.ethz.ch/people/knuttir

  49. 99
    Rick Brown says:

    The paper by Rogelj that Hank cites @96 is available at
    https://www1.ethz.ch/iac/people/knuttir/papers/rogelj12natcc.pdf

  50. 100

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