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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 111901 to 111950:

  1. There's no empirical evidence
    Tom, the energy trapped in the atmosphere by GHGs ends up in the form of heat, by those GHG molecules banging into other molecules. Energy is never actually trapped anywhere. We disagree on how the energy at the surface it transfered to the atmosphere. You say radiation being absorbed by GHG and then collisions with N2 and O2 molecules, I say via conduction at the surface and slightly, very slightly, by radiation absorption and then conduction to immediate surroundings. Convection merely helps speed that distribution, not reduce that total amount of energy. Have I stated otherwise? The total heat of the system increases. I believe I see the disconnect now that I quickly looked at #134. If you'll take a detailed look at 107-110, 128, last part of 130, and last paragraph of 131 it will help prepare you for my response to #134. Please take a moment to refute 107-110. You must understand that the journey of the energy within the system is just as important as to how much is incoming and how much s outgoing. Regions of the Earth's atmosphere are different temperatures, not only because of the input and outgoing energy, but because of the Transport mediums of available for the flow of energy. Your top of atmosphere reasoning (radiation only means of escape) has no explanation as to why the Troposphere averages 15 C at the surface and -54 C at the Tropopause (which is highly variable, altitude, from equator to poles).
  2. What caused early 20th Century warming?
    Marcus at 20:49 PM, if you are claiming that the cloud chart is dubious, please backup such opinion by providing data that invalidates that depicted in the chart. It is up to you to provide any longer term data available if you feel the period covered is cherrypicking. Lets see what you have in real data. It is well established that the variable and irregular cycle of warming and cooling of surface ocean waters determine how events such as El-Nino/La-Nina and the IOD, as well as other similar events in other oceans, are formed. There are only two sources from where variations in SST can originate, those being the circulation of heat within the oceans, or the solar energy being absorbed at the surface. Given it is accepted that the heat content of the oceans is increasing, then that obviously begins with increasing the SST. Irrespective of whether you accept the data of the cloud chart or not, what is not in dispute is that clouds provide approximately 2/3 total coverage and that coverage is irregular and follows certain patterns over both the short term and longer term as evidenced by the cycles of droughts. It has been established that the USA dust bowl era was due to a combinatiion of SST in the Atlantic and the Pacific that altered the atmospheric circulation across that portion of America. Only time will tell if that was a random event or part of a cycle that may reappear in the not too distant future.
  3. Weather vs Climate: Watch the waves, miss the turning of the tides
    #3: "Three decades is far from long enough in determining either weather or climate trends" OK, so look at a longer time span: This was made from a recent GISSTemp release going back to 1880. The plateaus represent each time a new high or low (in the temperature anomaly) is set. Hot summers (JJA average) continue getting hotter, but summertime lows don't get any lower; winter (DJF average) record lows don't get any lower than the -0.62 deg C anomaly from 1893.
  4. There's no empirical evidence
    theendisfar, you agreed that: 1. The Sun is the only input of energy to the Earth system (combined atmosphere, land, ocean). 2. CO2 traps some of that input energy. 3. Radiation is the only way for that input energy to escape the Earth system (combined atmosphere, land, ocean). Then surely you must agree that the total energy in the Earth system (combined atmosphere, land, ocean) increases as a result of the CO2 trapping energy. I'm talking about the total, regardless of where or how it is distributed within that system. Do you agree? Please give a simple, short, answer directly to that specific question.
    Moderator Response: Empirical evidence of point 2 is in the post at the top of this page, in the section "CO2 Traps Heat." Empirical evidence for the conclusion is in the section "The Planet is Accumulating Heat."
  5. There's no empirical evidence
    theendisfar - You object to Trenberths measurements because they're complicated? That is what you're saying in that post! Imagine the following conversation about some science conclusion: "How did you measure your data for X?" "I used a mass spectrometer." "Ooo - that's complicated. And that opens more questions than it answers!" "Then I suggest you try disproving mass spectroscopy - good luck, come back when you have something valid to say." The various uncertainties in the Trenberth energy budget measures are on the scale of the total convective energy exchange - it's that small a portion of the energies (~18-20W/m^2, listed as "sensible heat"). IR from the ground (and back IR from the atmosphere) was first clearly measured in the 1950's, and has been repeatedly measured since then with a variety of instruments: ~396W/m^2. So: when you've disproved FTIR and pyrometers, and come up with different estimates for global precipitation and energy of vaporization of water - then we can talk about your new (and measured) energy budget. Insisting, in the face of actual measurements, that your personal world view is overridingly true (in this case that convection is the major portion of energy exchange) is a Common Sense logical error. It reflects a lack of domain specific experience.
  6. Can't We At Least Agree That There Is No Consensus?
    poptech wrote : "No author has asked to have their papers removed. Pielke Jr. never did, Brooks never did, no one." Once again, I have to repeat what has already been repeated many times before, but which you still can't seem to understand : A quick count shows that they have 21 papers on the list by me and/or my father. Assuming that these are Hypothesis 1 type bloggers they'd better change that to 429 papers, as their list doesn't represent what they think it does. Roger Pielke Jr's Blog - Better recheck that list Of course, Poptech told Pielke what was skeptical about those papers and Pielke Jnr agreed and thanked Poptech for pointing out what his own papers were actually about. Actually, he didn't - he just ignored Poptech subsequently (probably a good strategy), and I suppose that speaks volumes about how he viewed his papers being abused in that way. To be more exact, Pielke Jnr showed Poptech where he could find proper scepticism, not made-up skepticism : "And if you want a good set of citations against certain "alarmist" conclusions (whatever you mean by that) I'd suggest the IPCC."
  7. Weather vs Climate: Watch the waves, miss the turning of the tides
    You've immediately confused the issue. Firstly you correctly state that to determine trends in climate, the changes in weather needs to be looked at over a long time span, then immediately provide a graph that uses the last 3 decades to support it. Three decades is far from long enough in determining either weather or climate trends when weather cycles have been identified where the rise and fall of the tides in a manner of speaking, takes 6 or 7 decades to complete both phases, in and out as it were, and reconstruction of El-Nino events indicate that perhaps any changes in the "tidal" frequency of them needs to be considered in terms of centuries. However, identifying any trends will always be the easy part, understanding what any trends and cycles mean and why they occur is the hard part. The tide analogy gives opportunity to consider whether the forces that drive the tides that affect even very small bodies of water, has what affect on the moisture suspended in the atmosphere?
  8. There's no empirical evidence
    Theendisfar, the energy trapped in the atmosphere by GHGs ends up in the form of heat, by those GHG molecules banging into other molecules. Convection merely helps speed that distribution, not reduce that total amount of energy. The total heat of the system increases.
  9. There's no empirical evidence
    KR, Clarification. This is relevant because if what I have stated is accurate, cannot be falsified, then one of the understandings must be wrong. 'Understandings' meaning, energy can be added to a system by slowing, trapping, what have you, the radiation rate through whatever mechanism you like, GHE, enhanced GHE, super enhanced, etc versus the 1st and 2nd Laws are kept intact. The Sun is the only source of energy that adds energy to the Earth's system. Well, Star light (entire spectrum) does too if you want to get picky. This is why I brought up the back pressure that would occur if you slowed the rate of cooling by reducing the radiation rate (speed of light) and instead had to use Convection, several dozen meters per second max. The 2nd Law clearly shows that if you reduce the rate of one means of energy transfer, it will automatically increase the rate of another means if available. Again, for clarification, convection only moves the energy to the top of the Troposphere where radiation becomes the only means to transfer energy and it again reaches the speed of light. What I'm saying is that the atmosphere itself can easily absorb the extra 2 Watts from CO2 trapping via increased convection rate and by the elasticity of the atmosphere itself. The altitude of the troposphere is much higher at the equator than the poles far a reason.
  10. Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
    First, Mars has no water, no tectonics plates and no magnetosphere or ozone layer. This means that you can hardly extrapolate observation of Mars to Earth. Also, the Mars Milankovitch cycle is rather different than teh Earth one. http://www.ifa.hawaii.edu/~norb1/Papers/2008-milank.pdf
  11. What caused early 20th Century warming?
    #30: "what TSI produced an equilibrium temperature of the Earth system in pre-industrial times with no other external forcings" I'm not sure what you mean. Why require 'no other externals?' Although volcanic cooling, as you suggest, is short-lived (even Pinatubo was only a 2-3 year event). And I am not aware of the significance of an 'equilibrium pre-industrial temperature'. The TSI data I've looked at (for example) show a short-term oscillation, which matches sunspot numbers reasonably well, modulated by long term signals (also present in sunspot numbers). For example, there were deep sunspot lows in the early 19th and again in the early 20th centuries. To the extent that surface temps follow these long term signal, do we not say 'its the sun?' However, when surface temps diverge from the solar signal, should we not look for the cause? What cause are you proposing?
  12. Weather vs Climate: Watch the waves, miss the turning of the tides
    Are those highs and lows for stations worldwide? In the US only? The graphic has a map of the US as its background ... Might be helpful to include a link to the source of the graphic.
    Response: It is US only. The paper it comes from is Meehle 2009. It's referenced in the intermediate rebuttal - we're still mulling over how much detail to include in the basic version - whether to include references or just link to the intermediate version for all the nitty gritty details.
  13. Is the sun causing global warming?
    The Ville You seem to be determined to find some excuse for disbarring Kirby's science. None of them valid.
  14. There's no empirical evidence
    KR, So it's not so much gibberish in that it can't be clarified, it was gibberish because of a lack of understanding and trust of the source. This is relevant because if what I have stated is accurate, cannot be falsified, then one of the understandings must be wrong. Barring someone able to falsify the understanding I have, I hold it to be accurate. And of course it has zero effect at the top of the atmosphere, where radiation is the only energy exchange with space. This is good, we agree. Convection stops at the Tropopause. Where the Earth was able to cool via Conduction, Convection, and Radiation starting at the surface, it lost Conduction with only a small amount of altitude, and then it loses Convection at the Tropopause. A transfer of energy means that energy has traveled over distance. To say that conduction plays no or little part in cooling the Earth's surface because Radiation is the only ultimate escape is nonsense. To say the same of Convection is equally nonsense. I took a look at Trenberth et al, is this what you're getting your info from? Imagine for a moment I had "provided a review of past estimates", and "performed a number of radiative computations", and "values constrained by", and ""but adjusted to an estimated imbalance", and "Revised estimates", and "radiation is adjusted", and "by making modest changes" in the short understanding I posted above. It opens far more questions than it would have answered. Again, just because convection only moves energy to the Tropopause does not mean it is not the primary transport of energy from the surface to it. Just because Conduction only moves energy from the surface to the immediate atmosphere above it, does not mean it is not the primary transport of energy to it. Any issues with #129? Make sense?
  15. University of Western Australia Open Day 2010
    I wish that some Universities in the US would create a similar program.
  16. The main culprit in mid-century cooling
    #4: very good point regarding China. From the late 90's to around 2005, the industrialized southern part of China (Shenzhen, etc) was covered in a dense haze, caused by emissions. Airborne dust and particles made it very uncomfortable to be outside. This has cleared up a lot over the past few years since around 2006. It is very possible that the Asian "brown cloud" helped mask the temperature increase on the early 00's, then, as it improved towards the end of the decade, temps started climbing faster again.
  17. Weather vs Climate: Watch the waves, miss the turning of the tides
    Now that's a great analogy. I'll definetly use this one.
  18. What caused early 20th Century warming?
    Ken #30 Alternatively you can estimate the effects of different forcing components by looking at linear models of the forcing components at different points in time. (Un)surprisingly we find that CO2 has been the main forcing component for the last 40-odd years, while the solar component was dominant previously. We also know that major volcanic forcings only last very short periods of time. So all this stuff can be estimated without estimating this 'equilibrium TSI'.
  19. What caused early 20th Century warming?
    muoncounter #28 Tell us what TSI produced an equilibrium temperature of the Earth system in pre-industrial times with no other external forcings (eg; volcanic cooling). With a fix on that 'equilibrium TSI' you can then estimate what excess Solar forcing has occurred over the 20th century and the total energy added to the system.
  20. What were climate scientists predicting in the 1970s?
    A tiny mathematical correction; Marcus's 100 ppm rise above a preindustrial level of 280 ppm would be a 36% increase, not 27%. And since current levels are actually around 392 ppm, it's really a 40% increase in CO2 (and rising every year).
  21. The Past and Future of the Greenland Ice Sheet
    Peter Hogarth wrote: I dont think Ned has suggested that current ice loss is greater than anything seen in the early holocene... and Berényi Péter replied: According to Figure 1 in the article current rate of ice loss is 26000 km3/century. That's three times faster than average rate of loss in any millennium in the last ten thousand years. So yes, he did suggest such a thing. Figure 1 shows the change in mass balance of the Greenland ice sheet over the past decade, as measured by GRACE. If Berényi Péter wants to claim that this rate of change is greater than the maximum decadal-scale rate of change during the early Holocene, that's his claim, not mine. I don't think that citing millennial-scale averages would be a good way to justify that claim. I spent a fair bit of time working on the phrasing of that post, to ensure that I didn't make any claims for which there was not clear evidence. Probably the most important point from that post is that the Greenland ice sheet was quite a bit smaller during previous interglacials. Since the projected 21st-century global mean temperature increase of 3C implies an Arctic warming of more than 3C, this is reason for concern. Thus, it becomes urgent to answer the question of how rapidly the Greenland ice sheet will respond to the upcoming temperature increase. As I discuss in the latter part of the post above, Pfeffer 2008 suggests that via realistic ice dynamics Greenland could contribute 16 to 54 cm as its share of a global sea level rise of 0.8 to 2 m by 2100. This also seems to fit well with Vermeer and Rahmstorf 2009. So I don't think there's any realistic way we could produce an Eemian (MIS-5e) ice sheet by 2100. But we could take a substantial step in that direction, and 0.8 to 2 m of SLR will have quite high economic costs in many regions.
  22. What were climate scientists predicting in the 1970s?
    GC, also consider this-if a mere 100ppm increase in CO2 emissions has been sufficient to raise global temperatures by +0.6 degrees C, what do you think another 300ppm to 600ppm might do to our climate? So long before we come close to running out of coal & oil, we will have been able to significantly altered our atmosphere & climate-perhaps to levels in which human civilization can no longer survive. Personally, I'd rather stop treating our planet's atmosphere like some giant laboratory-unlike the fossil fuel industry who're quite happy to use it in such a way.
  23. What were climate scientists predicting in the 1970s?
    Gallopingcamel #31, that's total *rubbish*. Pre-industrial levels of atmospheric CO2 was 280ppm, it is now above 380ppm. Even simple knowledge of mathematics should be able to tell you that this represents an anthropogenic increase of of 27% above natural levels, not 0.01% as you claim. Of course, RSVP would have us believe, wrongly, that an addition of anthropogenic heat-from industrial activity-that is less than 0.001% of the total heat received from natural sources-is sufficient to warm our planet in a way that a nearly 30% increase in IR-capturing gases can't. So who, again, is guilty of hubris?
  24. What caused early 20th Century warming?
    John D #22. Again with that cloud cover diagram. I've already pointed out how dubious that diagram is, given that its so obviously an example of CHERRY PICKING. Specifically, there is no indication if that peak on the LHS of the graph is typical or not. If its atypical, then the so-called decline in cloud cover is non-existent (if you go on cloud cover levels just a couple of years *before* the peak). When you can provide a diagram that covers a longer time-frame, then maybe I'll consider it. Fact is that, based on everything I've read, the strength & frequency of El Ninos & La Ninas is at least partly linked to the levels of atmospheric warming. Now whilst we had a warming trend of +0.06 degrees per decade from 1900-1950-driving by an upward trend in sunspot numbers, we've had a warming trend of +0.12 degrees per decade for 1950-2000 driven by....? Well, not increasing sunspot activity, that's for certain.
  25. Berényi Péter at 20:28 PM on 22 August 2010
    The Past and Future of the Greenland Ice Sheet
    #65 Peter Hogarth at 16:58 PM on 22 August, 2010 I dont think Ned has suggested that current ice loss is greater than anything seen in the early holocene... According to Figure 1 in the article current rate of ice loss is 26000 km3/century. That's three times faster than average rate of loss in any millennium in the last ten thousand years. So yes, he did suggest such a thing. In the three millennia before the beginning of the Holocene (15-12 ka ago) ice loss was faster, 20000-60000 km3/century (depending on model details), but that must have been caused by sea level rise induced breakup of ice shelves around Greenland, not local temperatures. Currently we do not have any large ice sheets melting far away from Greenland that could cause fast eustatic rise not compensated by local crustal rebound, neither have we extensive thick ice shelves around the island prone to sea level rise induced breakup. Therefore that kind of thing can not possibly occur now. Anyway, the "alarming" melt has started only ten years ago and has accelerated to its present rate in the last couple of years. Anything shorter than three decades is surely weather, not climate. Greenland (as opposed to East Antarctica) is a "wet" icesheet, not a "dry" one. Mass balance depends on precipitation to a high extent. With more open water around in the region increasing trend of snow accumulation of the last several decades should resume sooner or later. As many researchers have commented there is little sign of any known factor which will slow it down in the near future If so, tell them summer temperatures north of 80N are dwindling at an alarming rate during the last two decades. And this freezup in the high Arctic is clearly accelerating. In the meantime tell the Chinese to stop emitting untold amounts of soot in the atmosphere that's carried off right into the Arctic by prevalent winds. Soot pollution is not a necessary consequence of burning stuff. To make combustion more efficient and filtering smoke properly is not that expensive, the technology is ready, it is already done in any sane country. Best Hope for Saving Arctic Sea Ice Is Cutting Soot Emissions, Say Researchers While we are at it. Going for a ban on small diesel engines (a great source of tiny black carbon particles) and installing proper filters on large ones (including ship engines) is also a possible line of action, far more promising than the futile war on CO2.
  26. Can't We At Least Agree That There Is No Consensus?
    poptech -I REPEAT - I do not claim they are related to tobacco industry only that the journal is used for "tobacco science" style tactics. Namely, like the tobacco industry had with "Indoor and Built Environment", you have a tame journal for printing rubbish so you can claim "peer -reviewed articles" to back dubious claims. And look - you are doing it. And of course the knights of tobacco science were our friends in Heartland. If the journal was publishing anything of value to climate science, then other papers would be building on the science published there rather than demolishing it. Any sign of that happening - no. Cites to refute an article and cites in E&E dont count as "influencing science".
  27. Anne-Marie Blackburn at 19:39 PM on 22 August 2010
    The main culprit in mid-century cooling
    Hi Nigel. Yes, if you look at all the factors affecting climate change, aerosols have had a cooling effect and have therefore masked some of the warming expected from increasing levels of greenhouse gases. Some scientists have even suggested that we could inject huge quantities of sulfate aerosols into the atmosphere to keep global warming under control. Though technological and environmental issues mean that it's unlikely at the moment.
  28. The Past and Future of the Greenland Ice Sheet
    Given that increased ocean temperatures are helping to drive calving would it be reasonable to assume that once all the 'coastal' ice has broken away the rate of ice loss on Greenland (and Antarctica) should drop significantly? Or would exposed beach lead to greater melt and runoff? Have the regions of Greenland which are NOT covered by ice been seeing significant mass loss from the nearby portions of the ice sheet in recent years? From what I can tell the various 'mass balance' maps of Greenland the mass loss seems to extend well inland - presumably past any region that seawater temperatures should be impacting. I'm trying to get a handle on whether we'd expect Greenland ice loss to continue accelerating indefinitely or if there will be a slowdown once the coastal ice is gone.
  29. Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
    At least you are aware that there was a MWP. That puts you a step in front of John Cross. http://www.skepticalscience.com/medieval-warm-period.htm
  30. The Past and Future of the Greenland Ice Sheet
    Berényi Péter at 13:23 PM on 22 August, 2010 Thanks for fixing the link. I had not seen the Simpson paper, but at first glance fair to say your adapted chart is a simplification from their models? I'll digest the paper before drawing further conclusions. I dont think Ned has suggested that current ice loss is greater than anything seen in the early holocene... I think the fundamental argument is that current loss is not a transient event but a recently emerged and ongoing significant loss trend. As many researchers have commented there is little sign of any known factor which will slow it down in the near future (though I recall future shutting down of AMOC has been modelled).
  31. The Past and Future of the Greenland Ice Sheet
    BP, I'm trying to grasp how the volume of water that was on land and then moved to the ocean could cause a change in air pressure. Was this entirely due to rebound? (for that matter, I'll have to look up if rebound is actually conservative; that is to say, does what squishes down cause something to bulge up somewhere else? I find I don't really know or if I did I've forgotten...)
  32. gallopingcamel at 15:19 PM on 22 August 2010
    What were climate scientists predicting in the 1970s?
    Marcus (#26), The source of the carbon that humanity is adding to the atmosphere is fossil fuels. You talk about the last three centuries so use a bit of imagination and ask yourself how much will be left of the fossil fuel reserves in 2300 if we continue on our present course of industrialization and population growth. Long before the CO2 gets to 1,000 ppm fossil fuels will be so scarce (hence expensive) that they will be limited to special applications. We will be forced to depend on nuclear power and in particular the Thorium cycle. If we are clever enough we may even develop fusion power plants. The CO2 problem will have solved itself. Erratum from an earlier post. I said that mankind had added 0.1% to the atmospheric CO2 concentration. Mea culpa, I lost a decimal place and the correct figure is ~0.01%.
  33. Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
    Whenever I get told this one, I always ask what the temperature was on Mars during the Medieval Warming Period? Haven't had an answer yet
  34. There's no empirical evidence
    theendisfar - as in our previous conversation, I refer you to Trenberth et al 2009. The measured energy leaving the surface of the Earth run to 396 W/m^2 IR [pyrometers and FTIR spectrometers], 78 W/m^2 latent heat (evaporation) [from global precipitation and energy required to evaporate that much water], and ~24 W/m^2 convection [various estimates, but primarily what's left over]. Measured, repeatable (and frequently repeated) numbers. Unless you have measurements to the contrary, convection is 1/3 the energy of latent heat, and 1/16th the energy of IR, not the dominant effect you claim. And of course it has zero effect at the top of the atmosphere, where radiation is the only energy exchange with space. Next objection to the greenhouse effect?
  35. Berényi Péter at 13:23 PM on 22 August 2010
    The Past and Future of the Greenland Ice Sheet
    Unfortunately the Simpson 2009 link above is not correct. Here is a better one. Quaternary Science Reviews 28 (2009) 1631-­1657 doi:10.1016/j.quascirev.2009.03.004 Calibrating a glaciological model of the Greenland ice sheet from the Last Glacial Maximum to present-day using field observations of relative sea level and ice extent Matthew J.R. Simpson, Glenn A. Milne, Philippe Huybrechts, Antony J. Long
  36. What caused early 20th Century warming?
    #27: "in the early century, most of those years had low sunspot activity " 'Relatively' low sunspot numbers, yes; but the peaks are increasing through the first half of the 1900s. Anne-Marie's logic is sound. Long term cycles in solar output are apparent; Bonev etal 2004 reached this conclusion: "the present epoch is at the onset of an upcoming local minimum in the long-term solar variability. There are some clues that the next minimum will be less deep than the Maunder minimum" (emphasis added) That sounds like the next few cycles are predicted to continue the downward trend that began after the 1960 peak; so why are we still warming?
  37. Berényi Péter at 13:00 PM on 22 August 2010
    The Past and Future of the Greenland Ice Sheet
    #61 Peter Hogarth at 09:46 AM on 22 August, 2010 Your calculations are therefore dubious Not very much. According to Simpson 2009 between 10000 BP and 3000 BP the average volume change of the Greenland ice sheet is about -5700 km3/century. It translates to an eustatic sea level rise rate of 15 mm/century, still not alarming. The fastest loss rate they show is about -8000 km3/century between 5000 BP and 4000 BP. For the sea level it is still not more than 22 mm/century. As present ice loss rate is supposed to be much faster than anything seen during the early holocene when arctic temperatures were higher than now, it is either measurement error or a transient which can not last for long (a "weather event"). Greenland is very interesting, but rest assured, not dangerous for coastal cities. BTW, I have just found something curious. It is not immediately related to Greenland, but to the wider context of glacial - interglacial transition. As the great continental ice sheets of America and Europe melted, sea level rose by about 120 m. This added water displaced an equal volume of atmosphere, which increased air pressure over land everywhere on the globe by about 1%, except at former ice margins where uplift of land was larger than that of the atmosphere due to postglacial rebound. The pressure increase translates to a 0.5°C global land surface warming via lapse rate. This additional heating have not occurred over the oceans, so it must have had a pretty large effect on global circulation patterns. Anyway, it would deserve a closer look and somewhat more accurate calculations.
  38. What caused early 20th Century warming?
    Unfortunately your assertion that solar activity since the 1950's has been stable is wrong according to historical records of sunspot activity. Have a look at the following Australian government link where graphs of historical solar cycles are available. More sunspots equates to more radiated heat. http://www.ips.gov.au/Educational/2/3/1 (my apologies but I use Firefox and post links as per the hints provided) From the aforementioned link, you should note that sunspot activity in the early 60's was at an all time high post 1750. Sun spot activity during the 80's and 90's were the second and third highest for that period. As for the warming in the early century, most of those years had low sunspot activity hence I can't see how you can arrive at your conclusion that the warming is attributed to increased solar activity.
  39. The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
    Forget about mirrors, consistency, glass houses, your hurt feelings etc. theendisfar. The point is, you're arguing from the perspective that scientists are not trustworthy and that makes a discussion with you entirely pointless. Some of the self-described skeptics appearing here don't seem to believe they're victims of some fantastical plot run by a myriad of scientists and that means it's technically possible to have a productive discussion. Useful conversation with those expediently conjuring up imaginary scientific misconduct, conspiracies etc. is impossible because such artifices are a form of evasion, a way of saying "I doubt it" without having to provide any argument. If you've ever tried to talk down the anxieties of a person who is technically paranoid you'll understand what I mean. My observation is that the response of such a person when boxed in by logic is to imagine a new world with features excusing them from following logic. Mind, I'm not saying you're delusional, I have no way of knowing that. What I will say is that making broad, negative generalizations about the character and methods of a myriad of scientists does sound rather like inventing a new world with conveniently inexplicable features.
  40. The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
    theendisfar, in addition to the excellent replies you've already gotten in response to your invocation of Popper and your contention that consensus has no role in science, you should read the Skeptical Science response to the Argument There is no consensus". In addition to that post, I suggest you watch Naomi Oreskes's "Consensus in Science: How Do We Know We're Not Wrong?," which I link in my comment there. Also read another of my comments there, regarding the role of scientific consensus. Then my followup two comments here, and about math here, and about Kuhn's description of science here. Also relevant are comments about what science really is. You might start with mine.
    Moderator Response: Further detailed discussion of the nature and role of consensus in science is better done on the more general thread "There is no consensus," because this thread we are reading now is devoted more narrowly to the Oregon Petition.
  41. There's no empirical evidence
    KR, In particular, "Trapped radiation will only serve to slow the radiative cooling exhibited by black body radiation" is completely insensible - random words that don't mean anything to me. Thank you. I believe I can make it clear. If an object is radiating at 390 Watts/m^2 (m^2 is meters squared) and a GHG absorbs some of it and sends back 2 Watts, then the rate of cooling via Radiation has dropped to 388 Watts/m^2. Since a Watt is a joule/second, then the most obvious choice of words to me was to say that it 'slowed'. Keeping in mind that radiation travels at the speed of light, any IR trapped by CO2 is in effect trapped at the surface since it's frequency at the surface is every 1/150,000,000 seconds if trapped at 1 meter or 1/15,000 seconds if trapped at 10,000 meters. Temperature changes over such short time periods and so little energy can, for practical purposes, be seen as not changing. To describe the 'trapped' energy when it is away from the surface requires one to predict it's location within the atmosphere which is highly variable and since everyone is so concerned with it's contribution to surface temps, that is the obvious choice again. So, if you consider the 'trapped' energy as stuck at the surface, or better yet, when you are measuring it it is at the surface, then in practical terms you have reduced the radiation rate by 2 Watts. Now consider that a cubic meter of water at 15 C (average Sea Surface Temp) contains about 1.2 Billion joules, a reduction in cooling of 2 Watts is a 12 hour reduction of 86,400 Watts. Sound like a lot? Consider it takes a 4.1 Million joule increase to raise that 1 cubic meter of water 1 C. However, the radiative resistance does not impede Convection or Evaporation (where available), in fact, since a slight increase in Temperature will be observed at the surface, the Convection rate will increase accordingly. Better?
  42. Berényi Péter at 10:03 AM on 22 August 2010
    There's no empirical evidence
    #124 KR at 07:52 AM on 22 August, 2010 Delamere et al 2000 is an interesting paper. But they fail to show actual data for TOA emissions. Of course they don't do that. It is about modeling, not measurement. But they do provide some hints regarding why these quantities are not measured properly yet.
  43. Can't We At Least Agree That There Is No Consensus?
    "Popularity?" What's in a word? Citations are among other things a measure of the utility of a paper's content. In the scientific world a paper is useful when it helps to provide a framework for further exploration. So not popularity in the sense of "People" magazine. Meanwhile, all citations are not equal. A citation to an article from a paper authored by a pundit at a thinktank is not a very good indicator of that article's scientific merit. Poptech you seem very invested in E&E, presumably because it's a journal offering easy acceptance of articles that can't find a publisher elsewhere and thus many articles important to "skeptics" appear in E&E. Earlier I wondered if you could inform us about what fraction of the world's libraries subscribe to E&E. You'd mentioned a figure of something less than 500 libraries counting E&E among the journals on their shelves, that apparently being a usefully large number to convey the impression the journal has heft. Did you ever tease out that fraction from your information sources?
  44. The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
    Doug, A sudden epiphany, theendisfar? In a manner of speaking. Having commented on deception my argument was self defeating in a couple of ways. First, I was claiming AGW has done a poor job of proving anything, essentially speculating, and then I was doing the same thing with the regards to the folks I was detracting. Second, it has proven to be a terrible distraction, this post is further evidence of that. A different paradigm is exposed when you look in the mirror and apply the standards you hold others up to. I made a mistake and the quicker I own up to it the better. Too much torque, your credibility is snapped. Fair enough, do not take any of my statements at face value. What, you didn't before? :) I expect a fair amount of knocking, I made some dumb comments that I thought were harmless enough without carefully predicting the outcome. What I said is on par with many inflammatory remarks made about Skeptics, here and elsewhere. Not excusing any of it, just reminding those that live in glass houses.
  45. Berényi Péter at 09:56 AM on 22 August 2010
    There's no empirical evidence
    #123 KR at 07:49 AM on 22 August, 2010 do you think that in other wavelengths the top of atmosphere (TOA) emissivity has increased? Yes. Note that the measured TOA emissivity has decreased at all observed wavelengths in that graph. In the graph, yes. Not in reality. As I have already told you, the offset in the graph is arbitrary. TOA radiative imbalance, as measured by satellites, have some 6 W/m2 uncertainty. Can you produce evidence to that effect? If not, I can't take your comment seriously. You can't produce evidence to the contrary either. The 0.9 W/m2 radiative imbalance at TOA is only assumed, never measured. In order to be taken seriously you have to be able to tell assumptions and facts apart in the first place.
  46. The Past and Future of the Greenland Ice Sheet
    Berényi Péter at 06:03 AM on 22 August, 2010 Yes, my first comment was released in haste and was incorrect, apologies (I was looking at the bedrock uplift data for Agassiz and Renland, which amount to over 100m and around 300m respectively in the same period). I think we have to read the whole paper rather than making fast judgements. As you know, the percentage of d18O in the gas trapped in the ice core is used as a temperature proxy. It must be corrected for altitude (and latitude) hence an estimate of elevation at deposition time is required. Assuming similar d18O histories and known elevation history at one site allows past elevation at nearby sites to be more accurately constrained. Glacial Isostatic Adjustment has also to be factored in. Your calculations are therefore dubious (but at least not upside down...) The difference between elevation histories at core sites in the centre of the Greenland ice sheet and the margins gives evidence that the loss at the margins of the ice sheet is very sensitive to temperature changes and these margins have responded rapidly in the past. This is analogous to what we are currently measuring and seeing. The recent reversal in the long term downwards Arctic temperature trend (Kaufman 2009 etc), appears to require more than is possible from natural variations or forcings, and Vinther argues in his conclusion that relatively small temperature changes could lead to greater mass losses than previously thought. Vinther 2009 states: “Greenland ice sheet (GIS) is an important concern, especially in the light of new evidence of rapidly changing flow and melt conditions at the GIS margins”. I agree. These recent mass losses are not “weather noise”.
  47. The main culprit in mid-century cooling
    Could aerosols from industrialisation in China and coal fired stations elsewhere be damping down the warming trend over the last decade?
  48. Berényi Péter at 09:30 AM on 22 August 2010
    The Past and Future of the Greenland Ice Sheet
    #60 Peter Hogarth at 07:18 AM on 22 August, 2010 That is, the 10,000 year elevation change shown here is upwards (crustal uplift), rather than downwards (ice loss), as you have incorrectly interpreted it to be. No, it is not. You are surely not trying to tell us total gas content of an ice core decreases with increasing atmospheric pressure at depositional elevation. and I am not “you guys” Sorry for that, sir. It will never happen again.
  49. The main culprit in mid-century cooling
    Focusing on the cooling period as indicated above, 1945 to 1975, that period began with 2 declared El-Nino years that were much stronger than normal. Including those 2 years, a total of 10 years within the nominated period were declared El-Nino years. There was also 10 La-Nina years within the same period with the 3 final years being successive declared La-Nina years. HOWEVER, virtually the whole period, in fact the exact period was dominated with the SOI predominately and quite strongly in the positive (wetter) phase, and the IPO entirely and also very strongly in the corresponding negative (wetter)phase. The IOD was in the postive phase(drier) 3 times whilst in the negative (wetter) phase 4 times. The negative phase of the IOD is a pattern with cool SST in the Indian Ocean west of Australia, and warm SST in the Timor Sea to the north. For Australia overall, this cooling period was also a period of generally higher rainfall, so irrespective of what else may have been happening in the atmosphere, the amount and distribution of cloud cover would have had a determining influence on both how much the SST's warmed and cooled, and where, as well as where the moisture that formed into those clouds was carried to and deposited. Clouds also affect temperatures, causing lower temperatures during the day and warmer at night, so more clouds are not only indicated by the generally higher rainfall, but consistent with how temperatures varied also.
  50. Is global warming still happening?
    Excellent rebuttal! I have only one suggestion to make, it is already so near perfect;) In place of the fancy sounding word, 'indicator', use the more normal sounding word, 'sign', which really will be readily understood here as meaning the same thing.

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