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This Week

Filed under: — mike @ 4 May 2007 - (Türkçe)

There are a few minor items this week worthy of mention:

1. The CO2 rise. Who dunnit?

Here at RealClimate, we have been (naively, apparently) operating under the assumption that climate change contrarians had long ago moved on from the untenable position that humans are not even responsible for the observed increase in CO2 concentrations over the past two centuries. The dubious paper by Ernst Beck we commented on the other day indicates that there is indeed still a rear guard attack being waged. As if to drive the point home further, pundit Alexander Cockburn, known generally for his progressive views, has perplexingly disputed the existence of any link between CO2 emissions and rising CO2 concentrations in the atmosphere in a screed he penned this week for the online journal “Counterpunch” (also printed in The Nation). It’s hard to know where to start, since his piece is so over the top and gets just about everything so thoroughly wrong, it’s almost comical. So we’ll just hit the low points: (a) Cockburn claims that there is zero empirical evidence that anthropogenic production of CO2 is making any measurable contribution to the world’s present warming trend, despite the fact that not even such strident climate change contrarians as Pat Michaels dispute that there is a measurable influence of anthropogenic greenhouse gases on global temperature. Plus there’s all the empirical evidence of course (see the new IPCC report). (b) Going further, Cockburn brazenly opines that ‘it is impossible to assert that the increase in atmospheric CO2 stems from human burning of fossil fuels’ despite the fact that there is an isotopic smoking gun for this connection. He then (c) fails to understand that water vapor is a feedback not a forcing, and citing ‘expert’ Dr. Martin Hertzberg, quite remarkably states that ‘It is the warming of the earth that is causing the increase of carbon dioxide and not the reverse.’ Never mind that isotopic evidence proves otherwise. Upon what evidence does he base this assertion?

Since no anti-global warming op-ed these days is complete without it, Cockburn (d) resorts to the usual misrepresentation of lag/lead relationships between CO2 and temperatures during glacial/interglacial cycles as if they disprove the causal relationship between greenhouse gas concentrations and surface temperatures (see our most recent debunking of this favorite contrarian talking point here). Oh dear.

2. The other (Glenn) Beck–Even Worse!

CNN gave their resident shock-jock Glenn Beck a forum for spreading more disinformation on global warming in an hour-long segment entitled Exposed: The Climate of Fear (see also this discussion by “Media Matters”). We could pick apart his (rather thin) arguments, which constitute the usual cocktail of long debunked contrarian talking points. Suffice it to say, however, that the moment a rhetorician invokes Hitler, Nazi Germany, and Eugenics, it is the moment they are no longer worthy of being listened to (cf Godwin’s Law of usenet debates). We don’t seem to be alone in our opinion here. Beck’s performance earned him the dubious title of “worst person in the world” from analyst Keith Olbermann.

However, there was one amusing moment: Beck asked Christopher ‘Incorrect’ Horner what the key thing to google was that would show that Al Gore was wrong. Horner suggested the lag between CO2 and temperature in the ice cores. Of course, if you do Google that, the first hit is the RealClimate debunking of the issue. Thanks!

3. Nature’s new blog

Nature has started a new blog called “Climate Feedback”, which says of itself ‘Climate Feedback is a blog hosted by Nature Reports: Climate Change to facilitate lively and informative discussion on the science and wider implications of global warming. The blog aims to be an informal forum for debate and commentary on climate science in our journals and others, in the news, and in the world at large.’

We wish it well, remembering their welcome for RealClimate, though early reviews based on the first few posts are decidedly mixed.


280 Responses to “This Week”

  1. 201
    Harry Haymuss says:

    Re the response to #195,

    However, condensation giveth (net) in the mid troposphere and evaporation taketh away (net) at the surface. 1 cm of evaporation is 1 cm of evaporation at the surface.

  2. 202
    Timothy Chase says:

    My apologies. After some digging and lost data…

    Storch comes into this rather late.

    The criticism of the hockey stick was largely initiated with “Corrections to the Mann et al (1998) Proxy Data Base and Northern Hemisphere Average Temperature Series” Energy and Environment 14(6) 751-772 by Stephen McIntyre and Ross McKitrick in 2005. Long story: large scientific bodies commissioning peer-reviewed reports supporting the hockey stick, and a representative from the US Congress commissioning a Wegman report against it – which was not peer-reviewed. Over a dozen reconstructions by different teams using largely independent sets of data arriving at essentially the same hockey stick figure as the original paper. Storch came on the seen in April of 2006 with something decidedly different.

    Undoubtedly the “controversy” will continue for some time to come. Personally, I would be far more interested in what odds McIntyre, McKitrick or Storch might give me on whether the Arctic icecap will see the next ten summers.

    In any case, for those who are interested in a brief but fairly detailed history, you might want to see:

    http://en.wikipedia.org/wiki/Hockey_stick_controversy

    When something is this “controversial,” Wikipedia is generally pretty good at keeping it accurate – and keeping it from being vandalized.

  3. 203
    Timothy Chase says:

    I posted something that comes after Mike’s comment in #200, but I believe I may still have some of the chronology wrong – and the tone isn’t right. For those who are interested, I would strongly recommend the links Mike suggested. I had put the emphasis on politics (more or less), and both posts are much more informative and place the emphasis where it most belongs.

  4. 204
    fredrik says:

    Pat, thanks for your posts. I agree with most of them.

    Hank, I quess your post was directed to me.

    “People keep coming in with this same question over and over.”
    Ok, I haven’t seen if before.

    “I keep asking them where they’re getting their information and why they rely on it.”
    From meteorology books like, Fundamentals of weather and climate, Robin McIlveen and Boundary layer climats, T.R Oke. I rely on them because they are written by people working in meteorology and I like especially the first.

    “I haven’t ever gotten a clear answer to how this idea keeps being promoted, where they find it.”

    Researcher in meteorology seems to have the idea. I found the books in University libraries.

    “But it’s been such a steady flow of new names with the same, simple, wrong idea coming in here,”
    Ok, why it is wrong?

    “saying how radiation can’t be important”

    Where did I say that? The only thing I have said is that the diurnal warming/cooling is mostly through the energy transfer with the ground and convection. Radiaten from the sun and atmosphere warms/cools the ground but the direct energy transfer to the atmosphere seems to be small. The above books seems to mostly ignore it atleast.

    “so the whole theory about CO2 is wrong”

    I have never said that.

    “it has to be conduction and convection.”

    The diurnal variatons, mostly yes.

    “I’m convinced it’s a talking point on one of the PR sites for Western Fuels, or one of the political sites.”

    Or maybe universities books?

    “Please, someone, where are you getting it? Who’s being so successful at fooling new readers that they come to RC believing this stuff and then spend large amounts of time insisting the science is missing their ‘fact’? ”

    Try to understand what people write before coming to your conclusion. Just because C0_2 and radiation is not in every sentence doesn’t imply that the writer is incorrect or saying that people dont belive in global warming.

    Seriously, drawing the conclusion that people that belive that the main diurnal energy transfer in the troposphere is due to convection and advection, i.e. they drive the weather, dont belive in the greehouse effect is just ridicoulus. You really have trouble convincing people if one of the main parts in university level books on meteorology and climate is considered as propaganda from the oil industry. To be clear, the energy transfer on the ground depends on both SW and LW radiaten but the temperature in the atmosphere depends more on convection and advection compared to direct absorbation from radiation.

    I have expected more from you Hank and I was offended by your post.

    Ray, I agree with most of your post and tried to make the same point.

    “It does not make sense to look at any of these mechanisms in isolation. ”

    If for example one layer warms 1e8 times more by convection compared to direct absorbation of radiation, then would I say that it make sense to ignore the radiation.
    Conduction can clearly be ignored at 5000 m above the ground. I belive warming of the atmosphere by absorbation (radiation) could be ignored at 300 m on a sunny day.

    Timothy, I agree with your post. The problem is when some people tries to apply there knoweledge outside the correct field. When people with some knoweledge about an averaged climate model tries to apply that knoweledge to diurnal process. That atleast how I see it.

    Barton, try to understand peoples questions and points before you answer. You misunderstood alexander and you misunderstood me. Answering a sentence out of context is pretty bad. You have also clearly been wrong several times in this thread (atleast if context is included)

    I have read parts of Hougton’s book before and looked through it today. Nothing in it seems to contradict what I am trying to say. For example on page 14-15 is it written that the dominant mechanism of heat transfer is convection in the troposphere and radiation in the stratosphere. The first one is what I tried to say. Once again read people’s post before answering. Thanks for calling me a crackpot by the way.

  5. 205
    caz says:

    Re: #172

    Don’t forget – the IPCC itself claims that natural forces were the dominant cause of the forcing in the earlier half of the 20th century, …..

    How come most of the historical proxy reconstructions portray early 20th century warming as “unprecedented” then?

    Is it because early 20th century solar activity was unprecedented (at least as far as the past 1000 years or so is concerned)?

  6. 206
    Reasic says:

    Question: Why in the world is Roger Pielke, Jr. a contributor at the new Nature blog? Correct me if I’m wrong, but I don’t think he’s a climate scientist. Isn’t his doctorate in POLITICAL science?

  7. 207
    pete best says:

    This thread appears to cover just about everything related to climate change and the denialists from Von Storch and the hockey stick to alternative energy engines. However one item not on the list is that of the fact that climate scientists have been fighting the denialists so long now (since 1988 essentially) and still no real action to combat warming has taken place that I for one personally belive that it will take some 30 years before we are really tackling this issue globally and by then it might be too late to stop 2 degrees C of warming.

    430 ppmv currenly I beleive and come 2040 it will be around 490 – 500 ppmv. Surely that is the reality of our current situation.

    Hadn’t we better preapre society for a 2 C rise in temps?

  8. 208

    This is the way neocons groom their successors. People like Max Mayfield pave the way, and the next thing you know, Chris Landsea is director of the NWS and NHC. Imagine Roger Pielke, Jr. as presidential science advisor, and the next thing you know, your whole day is ruined.

  9. 209

    430 ppmv currently I believe and come 2040 it will be around 490 – 500 ppmv. Surely that is the reality of our current situation.

    Hadn’t we better prepare society for a 2 C rise in temps?

    You need to double check your numbers. It isn’t going to stop at 2 C.

    Wouldn’t it be more productive to prepare society for the reality of having to necessarily implement a technological planetary engineering solution, the now mandatory Anthropocene era, as an alternative response to the Neocene climate which we know is already coming? The only thing standing between today’s climate and the Neocene, are three large ice sheets and a large ice raft, two of which are already on the way out.

    With 10 billion people soon to be residing on this planet, energy conservation alone is not going to get us out of this situation. This is a universal natural test of intelligence, one of many that civilizations must pass in order to proceed. The conservation of energy is a guide, but it is no longer the solution. We need to get all of these future 10 billion souls interested in science, because it is in their own best interest, whether they know it or not. Religion doesn’t cut it in the real world, surely even cave men must have known that.

  10. 210
    Timothy Chase says:

    cas (#205) wrote:

    How come most of the historical proxy reconstructions portray early 20th century warming as “unprecedented” then?

    Is it because early 20th century solar activity was unprecedented (at least as far as the past 1000 years or so is concerned)?

    1. The proxies don’t show the earlier half of the twentieth century as unprecedented: they show the twentieth century as a whole as being unprecedented.
    2. In the earlier half of the twentieth century, our contributions were masked by aerosols – which nevertheless have a short lifespan in the atmosphere such that trying to counteract the effects of climate change would require greater and greater amounts of aerosols to compensate for increased carbon dioxide levels.
    3. Stating that solar variability was responsible for the majority of forcing in the earlier half of the twentieth century is not the same tehing as saying that it was responsible for all of the forcing in the earlier half. Our contributions would still have been responsible for much of the trend, and in logic, we could have been responsible for 49% of the trend.
    4. The population of the earth has expanded considerably since 1950, and therefore one would expect that our contribution has increased more or less proportionally to the populations since then.
    5. The IPCC may very well have been being conservative in its estimates of our contributions.
    6. Giving contrarians the extreme benefit of a doubt by assuming that the sun was responsible for 100% of the forcing during the earlier half of the twentieth century, according to the articles cited in what you were responding to, solar variability could only be contributing to 30% of the forcing since 1970.

    Now you should also keep in mind that given the natural forcing we are experiencing, we should currently be in a cooling trend. We aren’t.

    I would likewise recommend that you check out what has been happening to the arctic ice over the past fifty years. Currently our best estimate is that it will last only the next few decades before it is gone. However, this is likely an underestimate of the rate at which it will melt.

    I would also remind you that simply in terms of the rise in temperatures we have yet to see the full effects of our past forcing.

    1. So far, the ocean has absorbed the good majority of the carbon dioxide we have been emitting.
    2. As temperatures increase, the ocean’s capacity to absorb our emissions decreases. At some point it will in all likelyhood become an emitter.
    3. As the arctic ice melts, it will be exposing more dark ocean, leading to positive feedback.
    4. As the temperature of the ocean increases, this will increase the rate at which the arctic ice melts.
    5. As the permafrost thaws, organic material which has been locked away for millenia will become available to bacteria, and it will begin to release the methane and carbon dioxide which it has locked away for all that time, this, too will result in positive feedback.
    6. As the temperature of the ocean rises, it may destabilize shallow water methane hydrate deposits, which would further add to the amount of greenhouse gases which are in the atmospehre.

    Now I will note that the positive feedbacks mentioned above will not have an indefinite runaway effect. Nevertheless, they will be considerable. Moreover, the projections so far made by the IPCC have not taken them into account, conservatively estimating the future consequences of past and current emissions, and in the case of carbon dioxide, much of it will remain in the atmosphere for millenia.

  11. 211
    Nick Gotts says:

    Re #209 “With 10 billion people soon to be residing on this planet, energy conservation alone is not going to get us out of this situation. This is a universal natural test of intelligence, one of many that civilizations must pass in order to proceed.”

    My hunch is that something close to this explains the Fermi paradox (http://en.wikipedia.org/wiki/Fermi_Paradox). I conjecture that species capable of developing technology arise on many planets, but they all discover capitalism. This swiftly destroys their ecological support systems, and hence renders them extinct before they can get round to sending out von Neumann probes (http://en.wikipedia.org/wiki/Von_Neumann_probe). Each will have produced an expanding shell of radio transmissions a couple of light-centuries thick, but the chances we are currently passing through one that’s still strong enough to detect and decipher against all the background noise is probably negligible ;-).

  12. 212
    William Astley says:

    This paper that shows periodic cooling events in the Southern Hemisphere that appear to be concurrent with periodic Northern Hemisphere cooling events and solar activity minimums is interesting.

    “Solar modulation of Little Ice Age climate in the tropical Andes”

    http://www.pnas.org/cgi/reprint/0603118103v1.pdf

    “The underlying causes of late-Holocene climate variability in the tropics are incompletely understood. Here we report a 1,500-year reconstruction of climate history and glaciation in the Venezuelan Andes using lake sediments. Four glacial advances occurred between anno Domini (A.D.) 1250 and 1810, coincident with solar activity minima. Temperature declines of approx. 3.2 +/- 1.4°C and precipitation increases of approx. 20% are required to produce the observed glacial responses.”

  13. 213
    Timothy Chase says:

    Wlliam Astley (#212) wrote:

    This paper that shows periodic cooling events in the Southern Hemisphere that appear to be concurrent with periodic Northern Hemisphere cooling events and solar activity minimums is interesting.

    Science is interesting, at least when you are interested in science. It is interesting especially when you try experiments which have never been tried before. Then again, there is a saying: “May you live in interesting times.”

  14. 214
    James says:

    Re #209: [With 10 billion people soon to be residing on this planet, energy conservation alone is not going to get us out of this situation. This is a universal natural test of intelligence...]

    Err… I suppose this is getting far off into non-acceptable politics, but I’d think that the starting point for any intelligent analysis ought to be the premise that 10 billion people will be living on the planet. Or perhaps I should say can be living on it, because at this point it looks as though famines, wars, and other side effects will arrange things so that they won’t be – at least not for long.

  15. 215
    Hank Roberts says:

    Fredrik, as one pilot to another — I started hang gliding in 1978 — what I’m asking for is your sources.
    A bit more specific than ‘books’ in ‘university libraries’ — if you’ll give specifics I’ll try to get copies and read them and see what sense I can make of them.

  16. 216
    Danniel Saores says:

    I’d like to know which is the counter argument to Hertzberg’s argument that a 30% drop in human CO2 emissions, by 1930, didn’t affect even by 1 ppm the atmospheric CO2. I found this claim here. I’ve searched a bit for this specific point in this blog but I couldn’t find yet. Maybe there are something, since it’s so big, but I’m asking anyway…

  17. 217
    Danniel Soares says:

    Ops, forget it. Has been answered already on the comments.

  18. 218
    Danniel Soares says:

    About conservatism, leftism and environmentalism… the link I gave above, with the already mentioned point of dr. Hertzberg is some sort of leftist publication.

    In the other hand, there are conservatives in “the other side” too, such as “Republicans for Environmental Protection”, and whoever may follow green libertarianism (links to an article on wikipedia about that). I’ve also found what seems to be a far-right publication (frontpagemag.com) with an article (“The Right Conservative Position On The Environment” )defending right conservative environmentalism. Of course, trying to distinguish itself from left environmentalism.

    I think that this thing of labelling everything manicheistically as either left or right is some sort of psychological thing more than the reality of the things discussed. I do not really know the history, but taking these “anomalies” in account, plus somethings Thomas Lovejoy said in an enterview I watched (about Reagan administration, where Lovejoy had some position, having advanced important laws in environmental protection), I think that this political polarization arised initially by chance; prior to any polarization, it probably was discussed apart from that, only by the scientific viewpoint. But then happened to someone from the political left being more notoriously for environment, or someone from the political right being “against”, that then the other side reacted taking the opposite role, disagreeing with the other side just because that’s the way it use to be in politics.

    Perhaps someone could have been a “trigger” of the inverse polarization, if, say, someone from the right wing called attention to the environmental protection first, they could then have assumed the inverse roles instead…

  19. 219
    Steve Hemphill says:

    Re the response to #195, the reference states “The efficacy curve for the Earth must have an overall U-shape, with sharp upturns to snowball Earth on the left side and runaway greenhouse on the right.”

    I didn’t think anyone seriously believed in a “runaway greenhouse effect” anymore as the lapse rate of all planets is roughly adiabatic, with convection (or what?) stabilizing it.

    I think the point was that evaporation moves heat energy up to the middle troposphere, where it is released by condensation. It is moved away from the surface at a rate of ~0.8 w/m^2 per centimeter of evaporation, based on latent heat calculations. At an average global rate of precipitation (therefore evaporation) of one meter per year, that’s a change of one percent. Do we seriously know the rate of global precipitation within one percent? I doubt it.

    That I think is the point.

  20. 220
    Hank Roberts says:

    > diurnal warming/cooling is mostly through the energy transfer with the ground and convection.
    > Radiaten from the sun and atmosphere warms/cools the ground but
    > the direct energy transfer to the atmosphere seems to be small.

    But in fact it’s well known; Google will find many thousand pages describing how ice is made in the desert under clear night sky conditions. Now if you up the water vapor (clouds) this won’t work, of course, because the heat radiated up is radiated back down again from them.

    Making ice in the desert (Henry Spencer)
    The Romans made ice in the desert that way: insulate the container with a thick layer of straw during the day, expose it to the sky at night(unless it’s cloudy), repeat as necessary. A clear night sky is very cold.
    yarchive.net/space/ice_in_desert.html

  21. 221
    pete best says:

    Re 209/214, yes climate change will exacerbate existing difficulties with increased famine or drought or maybe floods and too much warmth. The 2 C of temp rise is allegedly the point where humans can no longer do anything about warming and hence it all becomes totally academic.

    I believe that 10 billion is too high a number and 8 billion by 2050 is more likely, however by the end of the 21st century the population is scheduled to fall back to 6 billion, the birth rate world wide is dropping.

    So lets prepare for a warmer world and tell our children of what is to come so that they can make plans to.

  22. 222
    ray ladbury says:

    Fredrik, The problem you are having is that you are trying to think of the heat transfer modes in isolation. That won’t work. You can’t neglect radiation just because much of the heat transfer in the day is due to convection and transfer of latent heat. That simply doesn’t work. Yes, energy transfer mechanisms differ between day and night. That doesn’t mean that air isn’t heated over warm rocks at night or that radiation (going up or down) isn’t important during the day. Look at a sunset–clearly the atmosphere is absorbing radiation.

  23. 223

    [[the temperature in the atmosphere depends more on convection and advection compared to direct absorbation from radiation. ]]

    Which part of “radiation from the ground transfers 350 watts per square meter to the atmosphere while convection and evaporation transfer 102 watts per square meter altogether” do you not understand? Then there’s the additional 67 watts per square meter the atmosphere absorbs from sunlight. The dominant mechanism which heats the atmosphere is radiation, Fredrik. Deal with it.

  24. 224

    [[I didn't think anyone seriously believed in a "runaway greenhouse effect" anymore as the lapse rate of all planets is roughly adiabatic, with convection (or what?) stabilizing it.]]

    It happened on Venus. That’s why it’s bone-dry today.

  25. 225
    Steve Hemphill says:

    Also Re 225,

    What do you mean by Venus is “bone dry”? The temperature on the surface is about 400° C. What did you expect?

  26. 226
    Hank Roberts says:

    > lapse rate … no runaway greenhouse

    But see, for example:
    http://www.physchem.ox.ac.uk/~wayne/atmos/lecture1.pdf

    “Runaway Greenhouse Effect Venus – all CO2 in atmosphere: no H2O”

  27. 227
    Steve Hemphill says:

    The lapse rate on Venus is approximately the same as the lapse rate on Earth. The difference is in the thickness of the atmosphere.

  28. 228
    pat n says:

    This week a forest fire in the Boundary Waters Canoe Area expanded to 52,000 acres and crossed the international boundary from Minnesota to Ontario. 657 firefighters and 16 helicopters have been employed as the fire continues to grow. A severe drought, which began early in 2006, led to the fire which began about a week ago. Lake Superior is near an 82 year low surface level. Many non-government people are blaming global warming but state and federal managers, and the media, blame Mother Nature.

    A photos of the fire fighting effort and a link to more photos and information are at:

    http://npat1.newsvine.com/_news/2007/05/12/715305-fire-in-the-bwca

  29. 229
    Timothy Chase says:

    This would seem related to #228…

    It appears that a new form of positive feedback has been kicking in a bit. As you are probably already aware, higher temperatures mean increased evaporation and precipitation, but rainfall will tend to occur closer to where the evaporation takes place. This results in increased risk of drought.

    With drought, plants are less able to make use of increased levels of carbon dioxide or even the amounts they had been adapted to, and are also more likely to release dioxide as the result of fire – hence the feedback.

    There is a non-technical article here:

    Surge in carbon levels shows vegetation struggling to cope
    David Adam
    Friday May 11, 2007
    http://www.guardian.co.uk/science/story/0,,2077117,00.html?gusrc=rss&feed=11

    Knorr et al. state in their conclusion:

    A test of model results against both atmospheric CO2 measurements and satellite observed vegetation activity shows good agreement, further supporting this hypothesis. For particular instances, such as the 1997/1998 extreme El NinË?o event, the assumption of additional CO2 sources, such as from fires, is necessary to explain the observations. For the anomalous CO2 rise during 2002â??2003, we find that it was probably caused by extremely widespread drought conditions in 2002 and 2003.

    Impact of terrestrial biosphere carbon exchanges on the anomalous CO2 increase in 2002â??2003
    W. Knorr, N. Gobron, M. Scholze, T. Kaminski, R. Schnur, and B. Pinty
    published 5 May 2007.
    GEOPHYSICAL RESEARCH LETTERS, VOL. 34, L09703, doi:10.1029/2006GL029019, 2007

    Obviously not the best of news…

  30. 230
    Hank Roberts says:

    Hm?
    http://adsabs.harvard.edu/abs/2006DPS….38.2612M
    “… The middle and lower cloud deck is sustained by a radiative-dynamical feedback whereby heating of the cloud base by radiation from the lower atmosphere destabilizes the lapse rate within the cloud region. …”

    More news soon:
    http://adsabs.harvard.edu/abs/2006DPS….38.1607M

    Much isn’t yet certain, at least as far as these folks are aware:

    “The new discipline of Comparative Planetary Climatology deals with the climate on Earth-like planets and addresses the physical processes that determine environmental conditions, the stability in each case against climate change, and the development of new experiments to further investigate these. By comparing the processes at work on Mars, Venus and Titan to those on our own planet we may gain a deeper understanding of global change on the Earth, the origin and evolution over the long term of this habitable world, and the processes behind threats such as greenhouse warming. Model temperature profiles which give a description of the state of the climate for all four of the terrestrial planet atmospheres in terms of simple physics, can be employed to study, and eventually to answer, questions of climate stability and change, such as: What do the climate systems on all four planets have in common? How stable are their current climates? What controls their stability? ….”

    http://www.ingentaconnect.com/content/klu/geop/2006/00000027/00000002/00003874

    Raypierre’s “Science Fiction Atmospheres” is an interesting approach to this. It appears not to be cut and dry simple.

  31. 231
    Steve Hemphill says:

    Re 230,

    I’m not sure what your point is. The abstract states “warmings of approximately 10 K are required to significantly reduce the cloud optical thickness”. Let’s not lose sight of orders of magnitude, eh?

  32. 232
    Hank Roberts says:

    Point being the scientists publishing as of this year are describing their efforts “to study, and eventually to answer, questions of climate stability and change, such as: What do the climate systems on all four planets have in common? How stable are their current climates? What controls their stability?” — open questions.

  33. 233
    pat n says:

    Re: 229, 228

    A big climate change factor that can increase forest and grassland fires is the earlier warm before vegetation greens up. The vegetation from the previous year can dry up more with warmer temperatures, winds and more days before green-up unless early winter and spring rains are persistent.

    Direct link to updates and images from the Ham Lake Fire in the Boundary Waters Canoe Area (BWCA).

    http://www.hamlakefire.com/

  34. 234

    [[What do you mean by Venus is "bone dry"? The temperature on the surface is about 400° C. What did you expect? ]]

    I’m referring to the fact that Venus very likely started out with oceans, either due to primordial volcanic outgassing or to accumulated material from comets. The water is gone. A runaway greenhouse effect (or Kasting’s (1989) proposed alternative of a “moist greenhouse effect”) is why.

  35. 235
    ray ladbury says:

    Steve, Hank is right about the value of comparative studies. It has been invaluable for geology. Already, from comparing Mars and Earth, we know that without a planetary magnetic field, the atmosphere gets dragged off into space by the solar wind.

  36. 236
    Steve Hemphill says:

    Re #234,

    That just violates basic thermodynamics.

    Re #235,

    I don’t disagree with that point at all. I am pointing out that the lapse rate on all 4 is basically adiabatic, which was the original point.

  37. 237
    Hank Roberts says:

    Steve,
    http://www.google.com/search?q=venus+water

    You’ve been making similar statements about what you believe ever since the John Daly days of Usenet; I don’t see you being convinced by the published science, but I also don’t find published science supporting your beliefs. Might this simply be left as a recognized religious debate like DOS vs. UNIX, until some hard science comes in? Else it’s “I believe” vs. “citations” repeatedly.

  38. 238
    Paul Dietz says:

    234: That just violates basic thermodynamics.

    Not in any way I can see. Perhaps you could explain your reasoning in more detail?

  39. 239
    Steve Hemphill says:

    Re #238:

    Hot air rises.

  40. 240
    Timothy Chase says:

    Re: Venus

    According to Kasting (1988), the runaway greenhouse effect on Venus was more or less independent of the carbon dioxide in its atmosphere.

    The important thing was the increased thermal flux early on in the evolution of Venus. About 15% more than what we get. This would have lead to increased evaporation of the oceans, which would have increased the greenhouse effect. Once the surface reached the boiling point of water (remembering to factor in the difference in atmospheric pressure), this would have boiled away the oceans. The rise in temperature at that point would have lead to the sublimation of silicates, releasing carbon dioxide which now constitutes 95% of the atmosphere. Water vapor would then photodisassociate, and hydrogen would have leaked from the atmosphere. Oxygen, being the highly reactive stuff that it is would have reacted with what was left.

    The temperature on earth would have to be a great deal warmer to put us in danger of this. Nearly 700 Kelvin with an atmospheric pressure of over 100X that which it currently has – unless someone figures out how to shutdown convection. Without that, we are in the realm of positive feedback but no runaway. From what I can see, the chances of our achieving this is somewhere between “not bloody likely” and “nil.” We have plenty of positive feedback to worry about, but it would appear that a runaway effect simply isn’t in the picture.

    Anyway, the tech paper I have in this area is:

    Runaway and Moist Greenhouse Atmospheres and the Evolution of Earth and Venus
    James F. Kasting
    Icarus 74, 472-494 (1988)

    If anyone has something more recent, let me know.

  41. 241
    fredrik says:

    Hank,
    “A bit more specific than ‘books’ in ‘university libraries’ — if you’ll give specifics I’ll try to get copies and read them and see what sense I can make of them.”

    I already gave references to 3 books that I have in my office right now in my post.

    “But in fact it’s well known; Google will find many thousand pages describing how ice is made in the desert under clear night sky conditions. Now if you up the water vapor (clouds) this won’t work, of course, because the heat radiated up is radiated back down again from them.”

    All I have tried to say is that this phenomena is due mainly to the energy transfer at the ground. The energy transfer at the ground depends on the radiation to and from the earth. Clouds radiate back energy and the ground cool less. Isn’t cloud absorbing the energy in the atmospherice window frequencies by the way? How large is the temperature difference at say 2000 meter at a cloudy night and clear night, difference in temperature at cloud level compared to non cloud level? The difference is huge close to the ground. I admitt that I dont have a perfect understanding of everything about the weather and that was the reason I asked questions.

    I still claim that my understanding is in agreement with the books I have read. The explaination in them agree with your explaination.

    Ray
    “You can’t neglect radiation just because much of the heat transfer in the day is due to convection and transfer of latent heat. That simply doesn’t work.”

    Pretty advanced meteorology books seems to mostly ignore the direct absorbation from radiation in short term phenomena, i.e. they dont include the radiation balance and heating from it in the atmosphere. All I have found is a mentioned that it probably isn’t important in the boundary layer but might be higher at higher altitudes where the time constants are longer and that the temperatur would fall 1.1 K per day from the radiation in balance. I was interested in if it actually could be ignored or not and wanted some real numbers but the result was that I had to just defend was it written in the books.

    Barton, why do you just ignore what I write? I am interested in the diurnal variation and heat transfer. Not what makes the mean value. The mean value depends mostly on greenhouse gases as I have said many times before. Happy know?

  42. 242
    fredrik says:

    Some general comments about approximations. Climatologiest on this site sometime make the assumption that convection doesn’t exist. See for example http://www.realclimate.org/index.php?p=58 and the learning from a simple model thread. This is a very large approximation as it would give rise to a lapse rate that isn’t close to the real on. Very few people complain about this approximation but a lot of people complain about the approximation that I and most meteorolgy books seems to do. Why? I would say that the first one is a much larger approximations compared to the last one. One gives result that agree with measurement to a much better degree compared to the other one.

    So why the completely different response? It just seems to be a good example that show that people is much more likely to belive an argument if they like the result. It is even more strange in this case because my approximation doesn’t even imply anything about whether the greenhouse effect exist or not. It just seems to be that this is not in 100% agreement with my simplified understanding, CO_2 is not includen in every sentence, and thus must be wrong.

    I wonder why articles with arguments like “Why does the stratosphere cool when the troposphere warms?” is actually written. It is based on a large approximation and a result that cames directly from the large approximation (the higher lapse rate) and uses some strange arguments. It is just here we have a result and we need some words in a row that should leed to the conclusion. I see no reason as why the explaination there should convience anyone that the stratosphere should be cooling as a result of more greenhouse gases. I see no difference in beliving the conclusion of that article or beliving some article from junkscience.com except that it is more likely that the conclusion in gavin’s article is actually backed up by science. The article doesn’t show it though.

  43. 243

    [[Barton, why do you just ignore what I write?]]

    I don’t ignore it. I just have a hard time trying to figure out what you’re saying, and I go with what seems to be the clearest interpretation. Sorry if I got it wrong. When you said “the atmosphere is heated mostly by convection and advection,” that struck me as incorrect.

  44. 244
    Paul Dietz says:

    Perhaps you could explain your reasoning in more detail?

    Hot air rises.

    The answer to my question is apparently ‘no’.

  45. 245
    Timothy Chase says:

    fredrik,

    I don’t know what your “approximation” consists of which is presumbly in the meteorology books.

    However, I strongly doubt that there is a “war” of any kind between meteorology and climatology – where one set of explanations contradicts the other. This sounds a little too much like the view by creationists that evolution violations the second law of thermodynamics. While undoubtedly there are some physicists who are creationists, most physicists undoubtedly accept evolution, and no physicist would use the second law of thermodynamics against evolution – unless he were completely misrepresenting the law for the purpose of attacking evolution.

    As for Gavin neglecting the effects of convection, he explicitly states as much.

    Moreover, without taking into effect convection we would be dealing with a runaway effect. In actuality the behavior of the atmosphere is very well understood – and modeling over decades is done at over a trillion flops per second. (The Earth Simulator was operating at that speed but it has been surpassed.) The biggest problem at this point lies with the aerosols and that is becoming quite tractible.

    Beyond the atmosphere, there are clearly more feedbacks in terms of the carbon cycle than what we have taken into account. Likewise, we do not currently understand the feedbacks involved in glaciers and the arctic as well as we would like, but we are beginning to get a great deal of data in this regard. I assume you have noticed that the artic ice has declined dramatically in the past few decades. The same thing is happening to the vast majority of glaciers outside of Antarctica, and even West Antarctica is in the process of collapsing.

    In any case, approximations are used where other effects are neglected because they are meant to illustrate the principles involved so that scientifically literate non-specialist can understand. To arrive at the whole picture, one would need to become a specialist – probably in a variety of different but closely related fields.

    Now why do I trust the climatologists?

    Well, I must admit that I am coming into this as a novice. However, I know that all climatologists accept the greenhouse effect, and while there are a few who claim not to accept the anthropogenic nature of current climate change, they are in the tiny minority. Climatologists have the well-developed and well-tested theories. Theories that make predictions and are in good agreement with the data. A great deal of data.

    They aren’t offering crackpot explanations that ultimately breakdown and contradict each other. And because I understand that given the very nature of a society with the well developed division of cognitive labor which exists in a modern economy, no one can be an expert in all fields. The last time anyone could be was a little over 2300 years ago.

    It is quite possible that you understand a little more science than me, but those who believe that they understand climatology better than the climatologists are self-deluded fools. I chose not to be deluded. And I would prefer not to see others deluded, particularly if it means that a lot of people are going to die. What these guys are doing is trying to save lives – in the decades to come.

    What are the people at JunkScience doing?

  46. 246
    Timothy Chase says:

    Frederik,

    One more point.

    Now I must admit once again that my understanding is somewhat limited, and I must also admit that the climatologists do not understand all of the positive feedbacks which are likely to make things worse and sooner than their models project. Moreover, in terms of my personal interest, I may be a little more concerned than most americans with what happens in Africa and other parts of the third world. However, as near as I can see, by the end of this century, large parts of the United States will begin to resemble Somalia. This is a future which I would like to see us prevent.

  47. 247
    Chuck Booth says:

    Re # 245 Timothy’s response to fredrik

    I don’t know how much disagreement there is between individual meteorologists and the consensus views in the field of climatology regarding AGW, but the World Meteorological Organization (http://www.wmo.int/pages/index_en.html) appears to endorse the conclusions of the IPCC reports:

    http://www.wmo.int/pages/documents/wmo_role_climate_change_issues.pdf

  48. 248
    Steve Hemphill says:

    Re #244,

    I think the answer is adequate if one understands how convection works – or rather, *that* convection works.

    If one does not know, maybe not. Otherwise…

    http://www.answers.com/topic/thermodynamics

  49. 249
    fredrik says:

    “However, I strongly doubt that there is a “war” of any kind between meteorology and climatology – where one set of explanations contradicts the other. ” The theories are definitely in agreement with each other and people working in both fields probably understands most in the other field. I was commenting on the responses I got from people here on the forum, people that aren’t experts in climatology or meteorology. The standard explaination of phenomenenon in the troposphere (weather) was considered incorrect and propaganda.

    “As for Gavin neglecting the effects of convection, he explicitly states as much.”

    Yes, but this doesn’t make the argument for the cooling of the stratosphere any better.

    “In any case, approximations are used where other effects are neglected”

    Yes, ofcourse. All models in any field is an approximation. It was interesting to note that some large approximations is allowed but some smaller isn’t. Radiation in all processes seems very important for some people here.

    “because they are meant to illustrate the principles involved so that scientifically literate non-specialist can understand.”

    Yes, but this is very shaky ground. People have tried to simplify for example aerodynamics and the coriolis force and the result is often far from good. The equal transit time “theorem” in aerodynamics does more harm than good and is completely wrong to take just one example. I thought Gavin’s article did to many simplifications and the result is an explaination of a phenomena that doesn’t seem to agree with reality at all. I have tried to found a good explaination for the cooling of the stratosphere due to CO_2 but haven’t managed to find one. Interested to see one.

    “but those who believe that they understand climatology better than the climatologists are self-deluded fools”

    I mostly agree but experts in a related field like numerical solutions of Navier-Stokes equations and statistics could definitely have valid points.

    “What are the people at JunkScience doing?”

    Propaganda.

  50. 250
    Paul Dietz says:

    I think the answer is adequate if one understands how convection works – or rather, *that* convection works.

    I do understand what convection is, and how it works, and, no, your answer is entirely inadequate. You appear to be someone who has made an unsupportable claim, and is working very hard from being required to support it.

    So explain your reasoning, sir, or I will be forced to conclude the hot gas is coming from you.


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