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Unforced Variations: Feb 2016

Filed under: — group @ 1 February 2016

This month’s open thread.

Just so you know, a lot of people have complained that these threads have devolved – particularly when the discussion has turned to differing visions of solutions – and have therefore become much less interesting. Some suggestions last month were for a side thread for that kind of stuff that wouldn’t clog interesting issues of climate science. Other suggestions were for tighter moderation. The third suggestion is that people really just stay within the parameters of what this site has to offer: knowledgeable people on climate science issues and context for the science that’s being discussed elsewhere. For the time being, let’s try the last one, combined with some moderation. The goal is not to censor, but rather to maintain somewhere where the science issues don’t get drowned out by the noise.

173 Responses to “Unforced Variations: Feb 2016”

  1. 1
    Matt Skaggs says:

    [Jan. 8]

    “12.What is your comment on Nicholas Lewis´ review of your article on climateaudit.org? http://climateaudit.org/2016/01/08/appraising-marvel-et-al-implications-of-forcing-efficacies-for-climate-sensitivity-estimates/

    [Response: Mostly confused, but there are a couple of points worth following up on. Should have the relevant sensitivity tests available next week. – gavin]”

    Just us patient grasshoppers saying hi!

  2. 2
    wili says:

    How about a “three strikes you’re out” approach. This gives new people (and old!) plenty of warning on what kinds of things are considered off topic. Then they are banned/boreholed, forever or perhaps for some ‘breathing time.’ Might be a little much to administer, but I think it will reduce the attention seeking.

    Probably 90% of the distracting commentary is the work of maybe a half dozen posters, so I think it could refocus discussion into more productive areas. Most of us even who don’t intend to can get side tracked and drawn into discussions by the sense that we need to respond to some trollish comment or other. So this can help us all stay focused. Thanks, as always, for a generally great and important site.

  3. 3
    wili says:

    I’m not seeing the ReCaptcha plug-in yet. Does that mean that posts aren’t going through yet?

  4. 4
    SecularAnimist says:

    I find real value in the climate science articles by RealClimate’s contributors.

    Frankly, there are other sites that IMHO do a better job of informing the public about the underlying science, and in particular about ongoing developments in climate science — e.g. ClimateCentral,, or SkepticalScience — probably in large part because they have professional science journalists on staff to create a steady flow of articles.

    The relatively infrequent articles at RealClimate seem to me more like “inside baseball” by and for the climate science community, and for the edification of laypersons with a relatively advanced technical understanding of the issues being addressed. That is a unique, and I think valuable, contribution, and I’m grateful to the RealClimate folks for taking the time to provide it.

    Having said that, I don’t think the “unforced variations” open threads do anything to enhance that contribution, and in fact they detract from it.

    It has become very apparent that the hosts have neither the expertise nor the time nor the interest to referee arguments about non-fossil fuel energy technologies, and that a handful of individuals continually take advantage of that situation to fill up the threads with ill-informed, inaccurate, disparaging claims about renewable energy, and then when criticized for doing so, they respond with the most juvenile insults and name-calling and personal attacks that I have seen since USENET was young.

    So, I respectfully offer two suggestions:

    1. Do away with the “unforced variations” open threads completely.

    2. Heavily moderate the comments on RC’s climate science articles. Indeed, I strongly suggest going beyond heavy moderation, and instead going to a “letters to the editor” approach, where comments are submitted to the article’s author for review. RC’s contributors then would accept ONLY those comments that are directly relevant to the article, and that ask important questions or provide important insight or additional information, and would publish those comments along with a response from the author. There would be no “discussion” between commenters.

    I just see no point in any of RC’s hosts wasting even one second of their time trying to moderate a free-wheeling, open discussion forum. And in the absence of aggressive, time-consuming moderation, the discussion threads will inevitably degenerate into a soapbox for self-impressed cranks who sneer at the moderators’ voluntary guidelines.

    [Response: The reason for the UV threads in the first place was because threads on topic posts invariably went off topic. So the UV threads dealt with that appropriately. The other alternative would be to add a real forum – but that still needs moderation. – gavin]

  5. 5
    mike says:

    Does anybody know of any study trying to do the same as this one, especially one that’s more recent?

    Probabilistic Forecast for Twenty-First-Century Climate Based on Uncertainties in Emissions (Without Policy) and Climate Parameters

    October 2009
    http://journals.ametsoc.org/doi/abs/10.1175/2009JCLI2863.1

    And the associated press release: http://globalchange.mit.edu/focus-areas/uncertainty/gamble

  6. 6
    Magma says:

    News has been going around the echo chamber recently that “300 scientists” have sent a letter to Congress insisting that the latter bring the NOAA to heel.

    1. Most of the signatories are retired.

    2. Many weren’t scientists.

    3. There appear to be, very generously, about a dozen climate scientists on the list. Only two (Richard Lindzen and Roy Spencer) are of any note at all.

    4. Showing the razor-sharp attention to detail and quantitative data they are renowned for, none of the blogs, publications and commenters touting this noticed that there are only 195 signatures on the list, not 300.

  7. 7
    JoeT says:

    I had a question in the 2015 Temperatures thread that I’m going to try again here. On the bottom of slide 10 of the NASA/NOAA news briefing is the ranking of 2015 for each atmospheric layer as measured by radiosondes. If I match this up with the RATPAC-A data set, it agrees exactly. Can I conclude from this that RATPAC was indeed the radiosonde data that is referenced here? Or were other data sets averaged in with the RATPAC data? If so, which ones?

    It’s interesting to see that the RATPAC surface data for 2015 shows a whopping 0.28C increase over the previous year, but I presume this is biased more to NH land data. Is that correct?

    Also if I look at the RATPAC 800 – 350 mb data, then 2015 is clearly the warmest year for the globe contrary to the satellite TLT data. Why not show the 850-300 mb data set in the presentation?

  8. 8
    Theo van den Berg says:

    Re wili @ 2: If this this not a site, where a member of the public, who is seriously interested in Climate Change, can ask the odd question, you should lock it up with logons for acceptable participants only. Can you recommend another site ? And wili, if you now strike me out, an email would be the right protocol.
    (Today received the 10 years of data from my local Met office. With it, I hope to prove in numbers, that at my location, I am experiencing a Greenhouse effect. If then true or not, I may want to interact about my results)

  9. 9
    sidd says:

    I support having a separate thread. Perhaps we could call it the Borehole.

  10. 10
    Killian says:

    For me it comes down to “ignore the trolls,” though the “trolls” tend to be mean-spirited, long-time participants that seem to feel entitled because they’ve never been moderated. Therefore…

    if you see something like, “#555 Somebodyrude said !!” you will know a troll has been seen round these parts.

    But what is a troll? Friends, a troll is not someone who you disagree with, think is unintelligent, doesn’t cite their sources to your liking, has a world view different from yours, uses poor logic, etc.

    A troll is someone who intentionally stirs iSht up. For the purposes of this site we can define two primary common types. Given the ironclad knowledge of climate changes currently ongoing, we can label denial as trolling: It has zero support or foundation.

    The second type is the Arrogant Ivory Tower Long-Timer. You know them by their rudeness. It’s not hard to “change the channel” and simply not respond to people you merely disagree with. It’s not hard to merely state responses without being denigrating or disrespectful. History, however, teaches us that long-time participants of any internet site tend to subtly shape, almost take over, a site in the sense their collective bullying and ridicule drives others away and a culture develops of ingrained intolerance.

    Ten years ago I got lots of “cite your sources” comments here. Now, I get almost constant disrespect from the core cadre of self-appointed gate keepers. This despite my forward-looking statements all being anywhere from generally to completely accurate. Yes, I abhor posting cites when I know everyone already knows what I am referring to. But, the other problem is the things I share have been largely ignored by the scientific community. In the groupthink that is this site at times, that equals *our* failing, not that of the science community. And it makes no difference to these gatekeepers that I have always been borne out as being correct. Just for some e.g.’s:

    Said Antarctica would be melting before 2100… in 2007.
    Said methane would be worse than mainstream thinks… in 2007.
    Have been on the pessimistic side of ASI… since 2007.
    Expected general degredation to be much more rapid than science said… since 2007… and acidification, anyone? Thermohaline, anyone? SLR faster than expected, anyone?
    Have talked about the importance of soil… then had an Australian group get all excited about all that life IN the soil. (Seriously.)
    The U.N. now talks about soil as a major mitigation pathway… something I have said since probably 2009.

    And on and on.

    I have said this before: There are different ways of knowing. Scientific experimentation does *not* trump all, it primarily confirms.

    Time for some tolerance around here for differing ways of speaking, knowing, contributing. It’s not hard to *not* be a butthead.

    Cheers

  11. 11
    Hank Roberts says:

    Why not show the 850-300 mb data set

    “the 850–300 mb levels (approximately 5,000 to 30,000 feet above the surface)”
    https://www.ncdc.noaa.gov/sotc/upper-air/201013

  12. 12
    jerry smith says:

    I don’t often look at these “open threads” since I have no motivation to do so: What will people blather on about? I mostly agree with comment #4, but I would have said “there are sites that do a better job of keeping the public interested in the underlying science, and in particular about ongoing developments in climate science — e.g. ClimateCentral,, or SkepticalScience — probably in large part because they have professional science journalists on staff to create a steady flow of articles.” This site should not compete with that, but complement it. When something significant (even significantly stupid) comes out, this is where I look for a competent analysis.

  13. 13
    singletrack says:

    In a thread having a preamble suggesting we need more interest, I apologize for having only a relatively boring question (or cluster of questions).

    Having read a lot about solar radiation at the “top of atmosphere” I have seen virtually nothing about where exactly that is. For the purposes of measuring radiation budget, what altitude is considered top of atmosphere (realizing it’s no doubt somewhat arbitrary in any case)? Where do measurements of this value come from?

  14. 14
    Hank Roberts says:

    > top of atmosphere

    I’m just a reader, not a scientist; all I did was try your question in ‘oogle:

    Here’s one discussion (there’s no single answer to the question)

    http://mynasadata.larc.nasa.gov/glossary/top-of-atmosphere/

    Another simple enough answer ‘oogle turns up: it’s where you can assume that

    The only quantitatively important energy sources to the whole system are radiative fluxes to and from space….
    … TOA (top-of-atmosphere) fluxes.

    That’s from:
    ATM 623: Climate Modeling
    Brian E. J. Rose, University at Albany
    Lecture 1: Planetary energy budget

    which would be worth looking through as a good introduction to the idea

  15. 15
    MA Rodger says:

    Spencer has posted for January. The interest in the satellite data is what it shows of the El Nino. (Note this is UAH TLT v6.0beta Spencer is posting.) The Jan 2016 figure is still below the peak of the 1998 El Nino temperatures, and is the 5th warmest on record at 0.54ºC (for comparison, Jan 2016 is 0.05ºC above Jan 1998) with top spot still held by April 1998 at 0.742ºC. The UAH rise continues at a lower pace than 1997/98. Nov to Jan was 0.21ºC which compares with the 1997/98 figure of 0.398ºC. While we await to see what RSS will do, it does begin to suggest that the temperature measured by the satellites through this El Nino (up at +4,000m) may not exceed the 1998 values.

  16. 16
    tony lynch says:

    Well, something had to be said.

  17. 17
    barry says:

    singletrack @13 – I have had the same question for years.

    “For the purposes of measuring radiation budget, what altitude is considered top of atmosphere…?”

    TOA = Tropopause? Outer limit of the exosphere?

  18. 18

    Singletrack,

    The Top of Atmosphere is technically at 100 km altitude, the “Karman Line.” In practice, 99% or more of the mass of the atmosphere is below the stratopause, at about 48 km up.

    The Solar constant at TOA averages about 1360.8 W m^-2 according to the latest figures. Since Earth is a sphere (4 π R^2 as opposed to just π R^2), this means 340.2 W m^-2 on average over the whole surface. With an albedo somewhere around 0.3 (modern estimates range from 0.28 to 0.33, a disappointingly huge set of error bars), the climate system absorbs 238.14 W m^-2 (I’ve got too many significant digits here, of course), corresponding to an emission temperature of 254.6 K.

  19. 19
    zebra says:

    Since comments about off-topic comments appear to be on topic, let me try to inject a little scientific inquiry into the mix.

    What makes it signal, and what makes it noise? And what kind of noise is it? (I can’t get the analogy right in my mind but pink, red, white, whatever– help would be appreciated.)

    Subjectively, or “eyeballing the graph”, it strikes me that there is a lot of repetition, including actual cut and paste of exactly the same language. Also, lots of long-winded rambling type diatribes containing those repetitions. That kind of thing is what I find most off-putting, not just “uninteresting”. But it’s also the kind of thing that could be moderated by a clever algorithm, which I don’t have the skills to produce, but I suspect someone out there does. Lacking that, something as simple as an upper limit on comments for individuals would probably be beneficial.

    As to whether something is “off topic”, I think the moderators could help by being clearer about this, perhaps even by tagging comments as such, rather than censoring them. We advanced chimps are capable of learning coughbeingconditionedcough that way, after all.

    I’m also going to point out that some of the questions that are clearly specific to climate science don’t get answered; maybe they could also be directed by a simple tag to FAQ where appropriate?

  20. 20
    JCH says:

    discussion about the TOA, top of the atmoshere

    As a layperson, I think of it as the lowest atmospheric layer at which the only energy leaving from within – in my world, reflected SW has never been within – the earth system is long wave radiation.

  21. 21
    wili says:

    theo @8, for heaven’s sake. How much clearer could I be that I am not talking about banning people for asking the occasional odd question. Reading comprehension much? But there needs to be some warning system and then a hard limit on people who get stuck on one off-topic topic and use up all the oxygen in the room.

    I do think that it would be a good idea to have a set of alternative sites to point them to if they want to discuss their particular bugbear. But often these trolls are already well aware of those alternative sites. Tell me what it is, in your case, that you so desperately and oddly want to discuss, and maybe I could find such a site for you.

  22. 22
    wili says:

    New work on the (to me, anyway) interesting possible causal connections between climate change and volcanic activity: http://phys.org/news/2016-02-volcanic-eruptions-ice-age-caps.html

    “Increase in volcanic eruptions at the end of the ice age caused by melting ice caps and erosion”

    “…much faster warming [than] cooling can’t be caused solely by changes in the Earth’s orbit – it must be, at least to some extent, related to something within the Earth system itself. Erosion, by contributing to unload the Earth’s surface and enhance volcanic CO2 emissions, may be the missing factor required to explain such persistent climate asymmetry.”

    Pietro Sternai et al.

    “Deglaciation and glacial erosion: a joint control on magma productivity by continental unloading”

    Geophysical Research Letters (2016). DOI: 10.1002/2015GL067285

  23. 23
    Patrick says:

    Ya’ll need a Facebook.

  24. 24
  25. 25
    Hank Roberts says:

    (Click it, that’s a link to climatescientists
    A public list

  26. 26
    Susan Anderson says:

    Well, that’s rather sad. One of the boringest serial offenders has already held forth above. It’s not about being wrong, it’s about being so sure one is right one loses a sense of perspective. It isn’t necessary to be wrong to be a bore and/or overly free with your opinions of others.

    On the whole, as a layperson, I exercise some care about posting here, but I do sometimes find gems and useful information, such as the identification of the “300 scientists” going after NOAA via the political anti-science zoo now in charge of our Congress. I’m sure I’ll be seeing that one around, and it is useful to be forewarned.

    We are in a pickle, aren’t we?

    I’m strongly for the “climate science from climate scientists” idea. Circumstances have changed (day jobs) but the detailed analysis sits in the background for people like myself who exercise their amateurism in hopes of alleviating the ranker forms of wrong.

    For a wonderful bit of advice on how to make a difference, I strongly recommend Admiral Titley’s commentary/advice here:
    https://www.washingtonpost.com/news/capital-weather-gang/wp/2015/12/14/commentary-after-the-paris-pact-thoughts-on-the-ted-cruz-climate-change-hearing/

  27. 27
    Chris Dudley says:

    It seems to me that climate models do tell us something about planning for future infrastructure. Recently, anticipated effects on stream flows and temperature were analyzed for power generation. http://m.phys.org/news/2016-01-worldwide-electricity-production-vulnerable-climate.html

    [edit – new rules!]

  28. 28

    Thank you Susan – the subject is dynamic and touches everything. I get the most interesting links from comments here, but yes, it requires personal filtering
    I must pass along a great interview with George Monbiot – one of the foremost progressive political thinkers in Britain today. Very recent. https://youtu.be/X9ViX90ehOQ 1 hour is worth it. He writes for the Guardian.

  29. 29
    Ric Merritt says:

    I recommend not getting your knickers in more of a twist than necessary (about silly comments, that is), which may render sterner measures from the moderators unnecessary.

    For example, Susan Anderson, #26, mentioned a serial offender who already appears in the comments to this post. I had to scroll up to see the forgotten comment, whose contents I hadn’t read the first time scrolling by, and didn’t read at this second glance either. I’ve never bothered with more ingeniously managed filtering, but I use quick scrolling quite a bit. Works for me.

  30. 30
    Magma says:

    For whatever it matters, the updated signatory list of the petition supporting Lamar Smith’s harassment of NOAA scientists now lists 302 names. As before, most are retired, many are not scientists, and few worked in any field relevant to climate. 82 of the signers are non-Americans working or living outside the U.S. 58 signers also signed the 2010 petition to the APS about its climate change statement.

  31. 31
    Mal Adapted says:

    I’m a regular visitor here, and an occasional commenter. The contributions of “knowledgeable people on climate science issues and context for the science that’s being discussed elsewhere” are of great value to me, and even the UV threads are worth winnowing for those. BPL’s reply to Singletrack at #18 is an example. Where else could I so conveniently ask a question like Singletrack’s and get that kind of concise and specific answer?

    Serial bores can be exasperating, but I’m aware of the timesink heavy moderation would entail for the site maintainers, and I’m not really bothered by content-free comments. Like Ric Merritt, I don’t find it hard to skim over boring exchanges by quick scrolling. If other commenters call my attention to something worth noting by a serial bore, I can simply scroll back to those comments and respond or not, as I feel appropriate. If I don’t check in with the monthly UV thread for a few days, I usually haven’t missed much. What’s the problem?

  32. 32
    Hank Roberts says:

    Barry and Singletrack — a more elaborate amateur attempt (mostly in hopes of drawing out a real scientist to correct my poetry here)

    “top of atmosphere” gets defined in various papers because it’s not a definite physical target everyone can point to. When you read a paper, do you find it defined for that paper’s purposes? It may simply be a known term that’s assumed to mean what it means in context.

    TOA would be where a photon headed out toward space isn’t likely to encounter a molecule that would absorb it — for radiation physics

    TOA would be where where one molecule heading outward isn’t likely to bounce off another molecule — for diffusion, I’d guess.

    TOA would be where, when ultraviolet breaks up water molecules, there’s a good chance the hydrogen will be swept off into outer space instead of recombining chemically with oxygen or something else.

    (That’s apparently how Venus and Mars lost their water — the hydrogen got away, escaping at the top of their atmospheres — tho’ for different reasons (Venus, close to the Sun, sunblasted; Mars, no magnetic field to hold the solar wind at a distance)

    that sort of thing. It’s where you can assume there’s no atmosphere on the outward bound path.

    That has to be an assumption of “not enough matter there, nothing likely to make an impact” on whatever particular question is being looked at.

  33. 33
    MA Rodger says:

    RSS is also posted for January with very similar outcome to UAH. The Jan 2016 figure is still below the peak of the 1998 El Nino temperatures, and is the 4th (UAH 5th) warmest monthly anomaly on record at +0.663ºC (UAH +0.54ºC). This is 0.113ºC (UAH 0.05ºC) above the equivalent period back then (Jan 1998), with the warmest anomaly on record still April 1998 at +0.857ºC (UAH +0.742ºC). Both satellite records show a slower paced rise than 1997/98. Today’s RSS Nov-to-Jan rise was 0.234ºC (UAH 0.21ºC) which compares with the 1997/98 figure of 0.392ºC (UAH 0.398ºC). This does suggest that the temperature measured by the satellites through this El Nino (up at +4,000m) may struggle to exceed the 1998 values.
    A graph comparing temperature records for the two El Ninos is here (usually 2 clicks to ‘download your attachment’). MEI for January will be posted in a day or so. Not graphed there, NINO3/4 continues to track a little above 1997/98 with predictions indicating to an El Nino very slightly longer in duration than in 1997/98 (when NINO3/4 hit zero at the beginning of June). SOI has been having a bit of a rest over recent days.

  34. 34
    Chris Colose says:

    wili (22)

    We had a two week “Volcanoes and Climate” summer school out in Iceland back in late summer…both Peter Huybers and Charlie Langmuir attended, who have advocated feedbacks between volcanic activity and glaciation/deglaciation (e.g., here). If you asked me whether it was important before this event I would have said no, since we usually think of the oceans as dominating the carbon cycle changes on this timescale.

    A lot of the geophysics was new to me, but I’ve been convinced that volcanic activity does listen to (de)glacial-like changes in ice volume/sea level (with some nuances about what type of volcanoes you’re talking about) and that there’s good evidence of this in the past.

    Still, the CO2 feedback might be on the order of ~5 ppm, so I still think it is second-order when trying to reach carbon cycle closure at the orbital timescale, and not big enough to have substantially altered climate.

  35. 35
    Hank Roberts says:

    Hmmmm. Is there a statistical geological epidemiologist in the house?

    Is there a “worst case” for vulcanism triggered by deglaciation?

    If we melt the ice caps say 100x faster than nature did in the past, does the geology respond with the events in 1/100th the time?

    That could shake things up.

    Only a few years ago nobody knew about subduction earthquakes, or the likelihood and possible magnitude of them, nor about remotely triggered earthquakes.

    What other “rate of change” event surprises may be in store?

  36. 36
    Hank Roberts says:

    Pictures speak louder; sometimes they whine or scream …. from the link I just posted, follow it to this map: “Locations of remotely triggered earthquakes in 1812, 1886” — wow.

    http://pasadena.wr.usgs.gov/office/hough/triggered.eqs.jpg

  37. 37
    Killian says:

    Re: #29Ric Merritt said I recommend not getting your knickers in more of a twist than necessary (about silly comments, that is), which may render sterner measures from the moderators unnecessary.

    For example, Susan Anderson, #26, mentioned a serial offender who already appears in the comments to this post. I had to scroll up to see the forgotten comment, whose contents I hadn’t read the first time scrolling by, and didn’t read at this second glance either. I’ve never bothered with more ingeniously managed filtering, but I use quick scrolling quite a bit. Works for me.

    Someone with a modicum of intelligence and self-control. Whaddaya know.

    It matters not that you don’t like someone, Susan. The trick is to keep your mouth shut about it because – surprise! – they likely think the same of you. Or, more likely, don’t give even the tiniest rats hind end *what* you think. Pointless to even bother. Solve problems, leave your ego and judgment out of it. Simple.

  38. 38
    Robert McLachlan says:

    Does anyone know the status of Richard Seager’s theory (http://www.ldeo.columbia.edu/res/div/ocp/gs/) on the relatively small effect of the Gulf Stream on climate? Seems relevant in view of the current influence of AMOC slowdown on the weather on the eastern seaboard and on local sealevel rise.

  39. 39
    B A Carter says:

    Re: 35, Hank Roberts – since the Baltic area is still rising after losing its overburden of ice, and this is after about 10k years, I doubt that rapid loss of ice will lead to rapid isostatic recovery. I suspect that any volcanic activity consequent to rapid loss of overburden will be significantly delayed but it will be interesting to see what happens.

    B A Carter

  40. 40
  41. 41
    Omega Centauri says:

    B A Carter #38
    There are two components to isostatic rebound. The elastic response is almost instantaneous. This is like the response of a spring to changing applied force. There is also a slow “plastic” response, as the underlying mantle adjusts to the changing pressure by slowly creeping from low to high pressure. The later is like watching an iron ball slowly descend into a slab of butter.

  42. 42
    Edward Greisch says:

    Moderator: “[edit – new rules!]” [27 Chris Dudley] Thank you very much.

  43. 43
    Vendicar Decarian says:

    #39 What comes next after the Anthropocene?

    The Mechacene.

  44. 44
    Chris Colose says:

    Robert McLachlan (37)

    The first-order influence of ocean heat transport in the present climate is to hold back the sea ice edge.

    It is common in idealized climate modeling experiments to replace a dynamic ocean with a “swamp” of some depth (say, 10 or 50 meters), often to cut down on computation expense of the simulation…effectively the ocean behaves as a bunch of 1-D columns capable of storing and releasing heat, as well as providing a source of water vapor and heat capacity, but does not advect energy between these columns. It has long been recognized that if you do this, you must artificially mimic the effect of ocean heat convergence/divergence (which is related to the surface flux out of the ocean) by prescribing a so-called “q-flux,” which is a correction term that can be derived from output of a fully-coupled GCM.

    If you set this q-flux to zero (essentially zeroing out ocean heat transport), the main effect is for the sea ice to expand and dramatically cooling the planet. Brian Rose (in my department) has done such an experiment, see his AGU abstract and I’m sure he’ll get around to writing this up. This is true despite the fact that the atmosphere is responsible for much more poleward heat transport outside of the deep tropics than is the ocean.

    Seager et al. essentially argue that if such an experiment were done in the limit of fixed sea ice, you’d get relatively minor effects, though they still show some 3-5 C cooling across Europe. But in this context, “small effect” seems to be referring to the relative temperature difference across the Atlantic (e.g., comparing UK to some location off the east coast of the United States) in which case it is probably true that the “Gulf Stream” (but not really, see the old stuff here at RC on Carl Wunsch and terminology) impacts both sides of the Atlantic similarly. But if you’re interested in absolute temperatures (or comparisons to basins with no such MOC, as in the North Pacific), then the Gulf Stream absolutely does matter and helps keep winters there more mild.

    We have paleoclimate evidence of a much less extreme version of the “zero q-flux” limit, namely reduced MOC during deglacial conditions, that absolutely involve large changes in Europe and elsewhere…including the tropical ITCZ location, the tropical rainbelt that persists (in the annual-mean) in the Northern Hemisphere ultimately because of net ocean heat transport into the Northern Hemisphere.

  45. 45

    I don’t comment here anymore – but how about the IPCC and 20 odd leading climate scientists?

    “In sum, a strategy must recognise what is possible. In climate research and modelling, we should recognise that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible.” https://www.ipcc.ch/ipccreports/tar/wg1/505.htm

    “The fractionally dimensioned space occupied by the trajectories of the solutions of these nonlinear equations became known as the Lorenz attractor (figure 1), which suggests that nonlinear systems, such as the atmosphere, may exhibit regime-like structures that are, although fully deterministic, subject to abrupt and seemingly random change.” http://rsta.royalsocietypublishing.org/content/369/1956/4751

    “Technically, an abrupt climate change occurs when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause. Chaotic processes in the climate system may allow the cause of such an abrupt climate change to be undetectably small.” http://www.nap.edu/read/10136/chapter/3#14

    “A vigorous spectrum of interdecadal internal variability presents numerous challenges to our current understanding of the climate. First, it suggests that climate models in general still have difficulty reproducing the magnitude and spatiotemporal patterns of internal variability necessary to capture the observed character of the 20th century climate trajectory. Presumably, this is due primarily to deficiencies in ocean dynamics… Finally, the presence of vigorous climate variability presents significant challenges to near-term climate prediction (25, 26), leaving open the possibility of steady or even declining global mean surface temperatures over the next several decades…” http://www.pnas.org/content/106/38/16120.full

  46. 46
    Chris Dudley says:

    ” The goal is not to censor, but rather to maintain somewhere where the science issues don’t get drowned out by the noise.”

    And yet a conclusion from a recent paper in Nature Climate Change got censored… Hopefully peer reviewed work in a climate journal is not considered noise here.

  47. 47
    nigelj says:

    Keep people very closely on topic on specific science subjects, and have a weekly or monthly general thread for absolutely anything, ranting included, and only very lightly moderated. Call it the ranting thread.

    The simplest and most obvious solution is often best. Occams Razor.

  48. 48
    Chuck Hughes says:

    No offense intended because I’m not the sharpest tool in the shed but, would someone please explain Russell to me? I read his short posts that link to his VVatts Up site but it seems a little, shall we say… esoteric.

    Am i missing something? My apologies to Russell.

  49. 49
    wili says:

    Thanks Chris C and Hank for relevant links and info. It’s almost like having a scientific discussion!! OMG! ‘-)

  50. 50

    For other people’s benefit, I’ll complete one of Robert Ellison’s quote

    In climate research and modelling, we should recognise that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible. The most we can expect to achieve is the prediction of the probability distribution of the system’s future possible states by the generation of ensembles of model solutions.

    So, yes, it isn’t possible to make long-term predictions of future climate states. However, this is not what is being claimed and is not what is being presented. What is typically presented are distributions of possible future states. Given that these are distributions, they give an indication of the probability of various future climate states. It is possible that the outcome could be quite different to the mean of this distribution, but the distribution then tells you something of the likelihood of such an outcome.


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