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Comments 101751 to 101800:
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damorbel at 08:07 AM on 12 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #149 archiesteel you wrote:- "I don't understand your question. I think you're confusing the "greenhouse" effect of GHGs with the capacity that every molecule has to be heated by an influx of radiated energy." Surely the important characteristic of GHGs is that they absorb (and emit) photons (EM energy) much more readily than other molecules such as O2 & N2? GHGs are uniformly mixed in the atmosphere until about 80km up, except for water. The point being, if GHGs absorb and emit radiation they will do that with local GHG molecules first, rather than travel all the way to the Earth's surface to add energy there. GHGs are at the same temperature as (local) O2 & N2; any warming effect of surface radiation heats the whole atmosphere at the height where it is absorbed. Further gases tend to have a uniform temperature because the molecules exchange energy by collision. In the atmosphere, at atmospheric temperatures, this energy exchange by collision exceeds the exchange by photons, simply because the mechanical momentum of a molecule exceeds the photon momentum by far. Also the density of atmospheric gases (including GHGs) gets smaller with altitude thus the energy density, even if the temperature did not fall with height, gets progressively lower with altitude; is there really going to be enough energy at altitude to raise the temperature of gases at the surface by the claimed 33C? -
cjshaker at 07:20 AM on 12 December 2010Greenland has only lost a tiny fraction of its ice mass
The ice cores seem to suggest that Greenland periodically warms enough to grow green plants, as a natural part of the glacial cycle http://www.itwire.com/science-news/climate/13352-ancient-dna-finds-greenlands-past-a-land-of-trees-and-butterflies http://news.nationalgeographic.com/news/2007/07/070705-oldest-dna.html Chris Shaker -
Ice data made cooler
If I may derail the discussion around RSVP for a moment, I made a small update to the Vostok viewer. Prompted by comments, I added mean yearly insolation, which is nearly a flat line. You can now see that (according to Laskar et al) total yearly insolation intercepted by Earth over the Vostok timespan changes little. Other updates on labels and usability will take more time. jg -
Eric (skeptic) at 05:10 AM on 12 December 2010The Scientific Guide to Global Warming Skepticism
#35 Badgersouth, such a comment on capitalweathergroup (a DC area site now owned by the Washington Post) brought me here. As a result I have refined my arguments so that they are no longer so easy to debunk. But I do honestly appreciate the feedback I get here, especially negative feedback. I happen to like negative feedback. -
RSVP at 04:33 AM on 12 December 2010Ice data made cooler
Marco #32 Thanks for pointing that out. Therefore the decimal point needs to be moved over. Instead of 0.0401%, it should be .041%. archisteel #31 "Why would anyone trust anything you say " No one should. Everyone needs to think for themselves. -
John Hartz at 04:17 AM on 12 December 2010The Scientific Guide to Global Warming Skepticism
Everyone: I'm now posting the following note on comment threads to media articles that address climate change and encourage you to do follow suit. "All of the anti-AGW poppycock posted on this comment thread is thoroughly debunked on the SkepticalScience website: http://www.skepticalscience.co.../ " -
John Hartz at 04:12 AM on 12 December 2010The Scientific Guide to Global Warming Skepticism
John: Kudos to you and your colleagues on a job well done! I recommend that you switch the color of the primary text from blue to black. I just printed the document and the blue text is not easy to read. In addition, it would be less costly for everyone to print the docuemnt if the primary text were black. -
muoncounter at 03:59 AM on 12 December 2010The human fingerprint in the seasons
My mistake. That's what I get for reading SkS at 6am local, prior to coffee kicking in. HR, ignore the RSVP part of my reply if you like. RSVP, no harm intended; feel free to chime in with waste heat if you like. -
archiesteel at 03:10 AM on 12 December 2010The 2nd law of thermodynamics and the greenhouse effect
@Michele: that's your rebuttal? Ouch. I think you need to learn more about the actual science before trying to present such arguments here. This isn't WUWT - most people commenting here actually know what they're talking about. @damorbel: I can answer the first two points. 1) Yes, I believe that's the whole point of the greenhouse effect: GHG molecules absorb IR and re-release it in a random direction. 2) Sure. Radiation is radiation. How would a CO2 molecule know where the IR is coming from? 3) I don't understand your question. I think you're confusing the "greenhouse" effect of GHGs with the capacity that every molecule has to be heated by an influx of radiated energy. Seriously, for someone who barged in here claiming the GHE violated the 2nd law of thermodynamics, you seem to understand very little about the actual physics involved. -
archiesteel at 02:58 AM on 12 December 2010The human fingerprint in the seasons
@muon: you were responding to HR, not RSVP, but I agree there's a chance the two are the same person. They use pretty much the same arguments, formulated with similar writing patterns. That said, it's not constructive to theorize about the secret identity of trolls. The best is to ignore the obvious ones, and carefully rebut the more subtle ones, as you are doing. -
Marco at 02:54 AM on 12 December 2010Ice data made cooler
RSVP, solubility of CO2 in water is not a factor 4, but 40 higher than that of oxygen. Similarly, for nitrogen it is not a factor 8, but 100. Data from the same link you provided. If you cannot even read a simple graph... Also note that there is a question whether the oceans are saturated with oxygen, nitrogen, and carbon dioxide (go ahead, do the calculation). -
archiesteel at 02:46 AM on 12 December 2010Ice data made cooler
@RSVP: you suck at math. "O2 in the atmosphere percentage-wise is around 500x that of CO2. For a 1 degree increase in water temperature you should have 125x the amount of O2 released. This means for every CO2 molecule you have 125 O2 molecules, which means the ppm CO2 goes down, not up." Let's say you have 1 CO2 molecule for every 500 O2 molecule. That's a relative concentration of 1/500. Now, we add 500 O2 molecules more. According to your ration, that means that 4 CO2 molecules are added (1 per 125 O2 molecule). The new relative concentration is thus 5 CO2 molecules (1+4) for 1000 O2 molecules (500+500), for a value of 5/1000, or 1/200. This means that relative concentration has more than doubled, and not decreased as you suggested. Why would anyone trust anything you say about science when you make such basic mistakes. Oh, right: nobody dose anyway. Please keep wasting your time trying to challenge good science with your very approximate knowledge. -
Alec Cowan at 02:20 AM on 12 December 2010The human fingerprint in the seasons
@Norman (#161) You may find interesting this resource: http://arctic.atmos.uiuc.edu/cryosphere/ and about ice anomalies in the Arctic: http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png (Check also the parent directory seaice_index/) http://psc.apl.washington.edu/ArcticSeaiceVolume/IceVolume.php -
Paul D at 02:08 AM on 12 December 2010The Scientific Guide to Global Warming Skepticism
"Psst skywatcher, dooon't mennntion theeeee ashhhhhessssss" -
Alec Cowan at 01:46 AM on 12 December 2010Ice data made cooler
@RSVP (#29) You keep changing your numbers, but no, you still have partial pressures out and even though you now have roughly included the important factor you left out before (atmosphere composition), you still have severe problems with your arithmetics (+,-,x,/ and %), as they became worse. Check that out. As you should make a total rebuilt of your background here, I suggest you to include detecting a difference when speaking of carbonate and dioxygen, dinitrogen and any di- form of a gas. And as a matter of epistemology, I think that trial and error should be strictly prohibited in the Comments Policy. -
RSVP at 01:23 AM on 12 December 2010Ice data made cooler
Alec Cowan #28 Its not about "knowing the subject" as simply going to the table. You can check the data for yourself. http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html The same kind of thing holds for N2, where CO2 solubility at 20 degrees (say) is 8x, but since N2 in the atmosphere is 2000x the amount of CO2, for every C02 molecule coming out of the water you will get 250 N2 molecules. That makes 375 O2 and N2 vs 1 CO2. As the ratio of CO2 is higher than 2500:1 you are right, it looks like CO2 ppm will increase. How much? It should increase in the order of 1:375 or 0.26% per degree increase in ocean's waters. Since CO2 is currenly around 0.04 percent, it would therefore go up to around 0.0401% for a one degree change. This doesnt seem very significant. -
muoncounter at 00:08 AM on 12 December 2010The human fingerprint in the seasons
#159: "when has the earth warmed and part of that trend did not include the effect of a GHG?" #160: "Are you implying that "all warming processes are made equal"?" As Alec Cowan notes, RSVP's question seems like either a silly one or a trick, a bit like 'do you walk to school or carry your books?' Isn't there always an 'effect of a GHG'? Its the GHE that "keeps the surface temperature of the Earth approximately 30 degrees C warmer than it would be if there were no greenhouse gases in the atmosphere." But I'm assuming you are the same RSVP who posited this not that long ago: the result for "waste heat" could be 0.1 C. So the only way it could be GHG is if all the waste heat magically goes away, which is what the "non contrarians" are going to have to say. From the vigorous defense of the 'its waste heat' position that either you or your twin RSVP mounted, I concluded you (or the twin) would answer your current question as 'the effect of GHGs is not at all significant' -- because you both think its all waste heat. So maybe you or the twin should be the one(s) answering your own question. And be sure to explain the observed asymmetry between winter warming and summer warming rates, both for the early-20th century warming and the current warming. 'To make it easier' for you(se): I assumed you would answer that its because of all the 'waste heat' we use to heat our homes in the winter. So I checked the monthly data from the USEIA, which show that (at least in the US), there's not really much difference in total energy consumption between JJA and DJF (we may be energy-hogs over here, but at least we're consistent). -
skywatcher at 23:20 PM on 11 December 2010The Scientific Guide to Global Warming Skepticism
Sorry John! But everything goes in cycles, doesn't it? (yikes! :) ) Well, cricket perhaps, though I'd never write off any Aussie cricket team. I wasn't meaning WACCo for the next edition of the Guide, but as a future article on SkepticalScience, unless of course the pattern verifies so strongly in the next few years that there is little argument about its anthropogenic cause! At present, I think I'd just class it as an hypothesis that needs more data to be verified, but maybe there are some folk out there with a better grasp of atmospheric circulation that might be able to shed some light on it. Best of luck for Perth! -
Norman at 23:07 PM on 11 December 2010The human fingerprint in the seasons
Moderator, Thank you for the links to the Arctic. I visit Sea Ice on a regualar basis. I couldn't find current Arctic anomalies in the search engine. Just gave me past data. I put both in my favorites and can check them out to keep up-to-date.Moderator Response: [Daniel Bailey] Did a little more digging. Try this site: http://data.giss.nasa.gov/gistemp/maps/. Be sure to set the projection type to polar to then get the polar anomalies you seek. -
Alec Cowan at 22:02 PM on 11 December 2010The human fingerprint in the seasons
HumanityRules wrote:So you are contesting with "since when have greenhouse gases haven't caused a greenhouse effect", aren't you? What is the purpose of your question and what has it to do with the seasonal trend? Are you implying that "all warming processes are made equal"? Certainly Physics doesn't change, but you know what are we really talking about.
Muon when has the earth warmed and part of that trend did not include the effect of a GHG? To make it easier I'll give you any time in the past several hundred million years. -
Alec Cowan at 21:12 PM on 11 December 2010Ice data made cooler
@RSVP As you were told, refrain for speculating if you don't know the subject. The figures were already given. If you want to have it correct you must research partial pressures and revise the simple arithmetic chain behind, as your "which means the ppm CO2 goes down, not up" shows you lost it at some point. Reading your paragraphs suggests that you suppressed some important information needed in the arithmetic chain and jumped to a conclusion. Research the web looking for that info, I won't offer that. @rest of the members I suggest not to provide basic information to those who, lacking the fundamental background and discipline, go fishing fundamental concepts using made-up assertions as bait. Please answer "you have ABC wrong, I suggest you revise DEF". It will suffice. -
damorbel at 20:34 PM on 11 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #143 KR you write:- "Greenhouse gases absorb some of the outgoing surface IR" This leads to question 1/ Do GHGs emit out going radiation? question 2/ Do GHGs absorb radiation emitted by GHGs? question 3/ What calculation of emission and absorption by GHGs do you use to decide whether the temperature of a particular quantity of gas will increase or deacrease? -
VeryTallGuy at 20:06 PM on 11 December 2010How do we know CO2 is causing warming?
scaddenp the basic physics is the laws thermodynamics plus the absorpotion spectrum of CO2. All very well understood already. The point I'm trying to make is that you can't experimentally measure greenhouse heating - you need the water vapour and temperature profile of the relatmosphere to do that, and that's experimentally impossible. Hence those demonised computer models. -
HumanityRules at 19:32 PM on 11 December 2010The human fingerprint in the seasons
155 Muon "if greenhouse gases are causing global warming, we expect to see winters warming faster than summer". Muon when has the earth warmed and part of that trend did not include the effect of a GHG? To make it easier I'll give you any time in the past several hundred million years. -
RSVP at 19:19 PM on 11 December 2010Ice data made cooler
Michael sweet #22 "releasing the same amount of both gases would substantially raise CO2 while leaving O2 essentially unaffected." CO2 solubility is around 4x that of O2. O2 in the atmosphere percentage-wise is around 500x that of CO2. For a 1 degree increase in water temperature you should have 125x the amount of O2 released. This means for every CO2 molecule you have 125 O2 molecules, which means the ppm CO2 goes down, not up. -
archiesteel at 17:04 PM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
@Camburn: "There are 30 year cycles to climate." Really? I'm skeptical. Do you have any evidence to back this claim up? -
Daniel Bailey at 15:22 PM on 11 December 2010The Climate Show #3: Cancun and cooling
Re: Bibliovermis I actually thought he was making a funny... -
Bibliovermis at 15:18 PM on 11 December 2010The Climate Show #3: Cancun and cooling
Umm... so? Is there a basis for that claim? If it is valid, why is it relevant? Please answer on a different page. There is a better area on this site for discussing the topic "it's cold somewhere." -
Norman at 14:39 PM on 11 December 2010The human fingerprint in the seasons
#151 muoncounter, From the article you linked me to. "The emergence of strong ice–temperature positive feedbacks increases the likelihood of future rapid Arctic warming and sea ice decline." In the next few years we will be able to determine if this theory is the correct one for the Arctic amplification. I will pay close attention to see if the sea ice extent goes below 2007 in the coming years. Hopefully it is not too late to make changes after a 5 year investigation period. Others are predicting a cooling phase that will lower temps until 2030. Do you know the webpage for current Arctic temp anomalies? When I look at this page most the Arctic (Canada, Alaska, Europe, and Russia look fairly cold). When I do a few spot temp checks like Yakutsk Russia or Yellowknife Canada they all seem below normal. Here is a link I look to daily to try and get a grasp of Global Temps in a quick view (unfortunately not anomalies though). Quick look at Global Temps. -
skywatcher at 13:44 PM on 11 December 2010The Scientific Guide to Global Warming Skepticism
Superb work John, thankyou for this excellent resource. I'd perhaps have added a mention to Tyndall and Fourier, highlighting the depth of time that we have understood CO2 causing warming, but that is a trivial point in an otherwise lovely readable and informative resource. I'd like to secong Phil's request for an article on the "Warm Arctic, cold continents" weather pattern. Cold weather is rapidly becoming the latest denier meme in the UK as we face our second (or third, depending on your location) really severe winter in a row. There are some interesting research articles around on WACCo (like the acronym Phil!) and on the hypothesis of reduced autumnal sea ice causing cold mid-latitude winter conditions, see for example the Arctric Report Card 2009 - Atmosphere or Petoukhov and Semenov 2010. But additionally some suggest that the remarkably low solar activity may be the cause, e.g. Lockwood et al 2010, at least for Europe. Given the Russian winter of 2005-06 (a focus of the Petoukhov paper) and the widespread nature of the 2009-2010 cold, maybe the Lockwood example doesn't work hemispherically? I know it seems strange to ask an Aussie about Pommie weather, especially during the Ashes :), but this is the best site on the Web for resources linked to debunking false skeptic arguments, or providing links to the good science.Response: You had to bring up the Ashes, didn't you? As an Aussie and a (very) passionate cricket fan, that's an intenseful painful subject right now. If we win the 3rd Test in Perth, I may consider including WACCo in the next edition of the Guide. -
Daniel Bailey at 13:17 PM on 11 December 2010We're heading into an ice age
Re: 180 Right next to the pictures of farmland and skyscrapers... -
Camburn at 12:48 PM on 11 December 2010The Climate Show #3: Cancun and cooling
Well, at least Cancun seems to be cooling. -
Joe Blog at 11:56 AM on 11 December 2010Stratospheric Cooling and Tropospheric Warming
mars at 09:40 AM says "When convection takes place the work is done by expanding the air parcel in the first phase of warming until this happens the air parcel will not ascend." Yes, the same as a cylinder compressing air, you apply work to the piston, squishing the air, the energy applied to the piston, is now contained in the air, as well as the prior existing energy is now more tightly compressed... now the rise... pushing up the piston, putting the energy applied by the piston back into the piston, until the air is back at equilibrium, with the same amount of energy contained in the volume of air prior to the compression. The same applies to the atmosphere, work is done, by energy being added to a parcel of air, the air rises, displacing the air above it(the piston) expanding, with the energy from the work being used to displace the air above, redistributing it into this, until it is at equilibrium with its surroundings... If the air didnt have more energy in it than the adiabatic rate dictated, it wouldn't rise, or less it wouldn't sink... So work goes both ways, it takes work to apply pressure/add energy... when it expands, it releases this energy, work is done, until it is at equilibrium. otherwise it would never stop rising, it would always contain more energy than the adiabatic rate dictates. -
muoncounter at 11:49 AM on 11 December 2010We're heading into an ice age
#179: I would say cool, but somehow that doesn't seem right. Did you notice they have an 'Ice Museum'? As in a place where someday children will go to see pictures of ice? -
Daniel Bailey at 11:10 AM on 11 December 2010We're heading into an ice age
Re: muoncounter (175) Check out the video I linked in your comment. The Yooper -
Daniel Bailey at 10:10 AM on 11 December 2010The human fingerprint in the seasons
Re: TOP"Yes, look at the graphs."
OK, what should I be seeing?"Towards the end of November from 2008 on the temps are below normal till March or so the next year."
Um, you mean the parts not in the middle of the range or warmer than the range? OK, just the colder, cherry-flavored parts, check. (To make this exercise easier, I've stitched the winter months of 2008-2009 into one graph, below) So, a laser-focus on the parts of the winter temps that you want to see (the tasty, cherry-filled parts) shows a portion of the winter was below the long-term variation. Check. Ignoring, of course, the unpalatable part of the winter in the normal range of variation and the very unsavory part warmer than the long-term variation. (Similarly, here's the winter of 2009-2010, below) Needless to say, most of this winter was simply too bitterly warm to eat. Good thing that jet stream was there to keep us cold, right?"Such anomalies can be just a few feet deep as anyone who swims in inland lakes can attest to."
TOP, few "swim" in Lake Superior. Even the locals. Even at the height of summer it's simply too cold (those balmy top 6" rarely top 50 degrees or so). The fact that one can do a full-body immersion (I'm 6'-3") for hours at a time now is simply without comparison (twenty years ago I would not have dreamed of attempting this ever in my lifetime). That's why we locals usually swim in the inland lakes or where the streams meet Lake Superior (we know where the tide rips are; the "fudgies"/tourists don't, sadly and we lose a few every year)."I don't know if there is anything like Argo in Lake Superior, but the full depth is what needs to be looked at, not just the top few feet."
Yikes! You mean all 1,332 feet deep? Valuable stuff will get frozen off... Seriously, TOP, that's why we use baselines and anomalies. To measure the deltas. Which show this area is warming. Including Lake Superior. If you want to find correlations that actually exist, look at the droughts of the past few years relative to the long-term records or run the local temperature record for the past few winters and correlate it with the Arctic Oscillation. You'll find local weather here is colder during the negative phase. OK, fun's wearing off now. Lemme know if you find a statistical correlation on that AO thingy. The Yooper -
Camburn at 10:04 AM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
dana1981: I look forward to discussing Dessler's paper. dhogaza: There are 30 year cycles to climate. 1/2 of that cycle is 15 years. That is why the 15 year temp criteria. The reason for the 95% is that is the significance level of HadCrut temp data. That is stated in the literature. I did not pull that out of thin air. Back to clouds again. No comment on Sun's paper at all?Moderator Response: [Daniel Bailey] If you are going to respond to archiesteel at 133 below with links to sources, per the Comments Policy, please provide a summary of what you think the linked reference means in support of your position. Thank you! -
muoncounter at 10:04 AM on 11 December 2010It hasn't warmed since 1998
The new images here should remove any doubt that those still clinging to the 'it hasn't warmed since 1998' mantra are truly in deep denial. The above is temperature anomaly for the period 2000-2009. The clincher is the companion image, both available full scale here, which represents 1970-1979, when things were a lot bluer. Be sure to check the color scale. -
muoncounter at 09:56 AM on 11 December 2010It's cooling
82: "Iris effect" Good catch, Yooper! Now that's one I hadn't heard of. So off to the google machine: I suppose NASA's Revisiting the iris effect is old hat, but it does offer up a great one line come-back to the pretenses of the cherry-picker: “You cannot make a scientific judgment,” Wong said, “until you’ve done the complete analysis. -
mars at 09:40 AM on 11 December 2010Stratospheric Cooling and Tropospheric Warming
Joe Blog at 22 Re Para 3 When convection takes place the work is done by expanding the air parcel in the first phase of warming until this happens the air parcel will not ascend. The air parcel once it starts to rise continues to do so because it is less dense than the surrounding air mass but as it rises the external pressure is lower and therefore it expands. The process is adiabatic that means no heat is added or taken away from the system during the ascent phase. To put it another way the same amount of heat in a large space translates to a lower temperature. Physically due to gravity the heavier air parcels fall to the bottom of the atmosphere and the lighter rise. The colder air having been displaced downwards is now at a higher pressure and therefore its temperature is higher but again this process is adiabatic so no work is done, and yes heat does accumulates at higher levels during the day but of course it is lost again during the night. The bit I am not sure about is whether this is agreement with Joe or Tom. -
Elise at 09:18 AM on 11 December 2010The Scientific Guide to Global Warming Skepticism
I LOVE it! Very useful. And... has anyone worked out a daily-life example for the statistical probability that all these ominous numbers are random, perhaps in terms of poker? Such a thing could be a vwonderful grand finale for your list. For example, see Larry Gonick and Woollcott Smith's immortal book, The Cartoon Guide to Statistics? They open the chapter on testing hypotheses with a legal example about racial bias... I'm skipping the calculations here... in which the cartoon lawyer concludes triumphantly that the chances of getting an 80-person jury panel with only 4 African Americans work out to about .0000000000000000014. "Is that a small number or a big number?" says the judge. The lawyer explains, It's less than the chances of getting three consecutive royal flushes in poker. So the judge rejects the hypothesis of random selection, confiding to the reader, "If I was in that poker game, I'd a started shootin' after the second royal flush..." Yeah. Keep up the good work. Elise -
TOP at 09:00 AM on 11 December 2010The human fingerprint in the seasons
@107 Daniel Bailey Yes, look at the graphs. Towards the end of November from 2008 on the temps are below normal till March or so the next year. This is about the time the jet stream moves south cutting off the flow of warm air from the south. Warm air comes up from the South to warm even the UP. Current NWS climate summary CF6: [TEMPERATURE DATA] AVERAGE MONTHLY: 17.4 DPTR FM NORMAL: -3.8 HIGHEST: 29 ON 1 LOWEST: -3 ON 9 And the record high was a surface temperature in August, not in December. The article states, "highest average surface temperature ever, a balmy 68.3°F." Such anomalies can be just a few feet deep as anyone who swims in inland lakes can attest to. I don't know if there is anything like Argo in Lake Superior, but the full depth is what needs to be looked at, not just the top few feet. -
Daniel Bailey at 08:17 AM on 11 December 2010It's cooling
Yup, still happening: NASA: Hottest November on record, 2010 likely hottest year on record globally — despite deepest solar minimum in a century And the zonal means plot showing the polar amplification: Zonal Means Plot for November 2010 Don't know about you, hoss, but this cowpoke says the heat is on... ...but I still feel significantly lucky! Iris effect, anyone? Bueller? The Yooper -
scaddenp at 07:39 AM on 11 December 2010How do we know CO2 is causing warming?
VTG - to demostrate the basic physics of the greenhouse effect, no it doesnt. For the real atmosphere, you can just measure the effect directly but most people dont have access to satellites or appropriate instruments. Henry - it can be harder than you think to get this right. What wavelength really is that warming lamp emitting cf to the spectral sensitivities that you want? Water will mask the CO2 effect. Better to use two bottles and do simultaneously (otherwise you might be just measuring a difference in conduction heating between your two times). Have bottoms of bottle black and irradiate with normal sunlight or strong lamp. Need to think very carefully about your setup to eliminate conductive effects. -
dana1981 at 07:33 AM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
dhogaza #129 - Yes, Dessler discussed the well-established water vapor feedback in his paper, as opposed to the much more uncertain cloud feedback. We'll discuss that in the blog post on his paper. Besides which, there is a large body of empirical evidence that climate sensitivity is 2 to 4.5°C for 2xCO2. I agree, the speculation that there will miraculously appear a negative feedback just in time to prevent dangerous warming levels is wishful thinking. -
dhogaza at 07:30 AM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
Camburn: "Thank you dana1981. If 2010 ends with temps of statistical importance, I will agree. It is pretty plain and simple." What, in your mind, makes 1995 as a starting point more meaningful than 1994? Other than the fact that cherry-picking 1995 allows for the claim that since that date, significance onlyr reaches 93% rather than 95%. So, what's your non-cherry picking scientific reason for picking that date? Also, 95% significance for publication etc has been more or less picked out of a hat by statisticians, there's no theoretical basis for that number, and indeed some fields typically accept less significance, while others require much higher significance. Statistics are a tool, and the 95% level is a guideline, nothing more. Fisher (the Godfather) talked about this quite a bit, he'd be the last in the world to insist that >=95% confidence means "true" while <95% means "false". Such claims are just bullshit. -
dhogaza at 07:26 AM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
"The cloud issue seems to be the most mysterious of all the factors. No clouds or water vapor feedback and a doubling of CO2 gives a 1.2 C warmup." However the water vapor feedback is well-established, with solid observational data from space backing it up. There's nothing going on with temp trends to make one believe that we're observing a significant negative feedback today from clouds, and the arguments that we will magically see such a negative feedback kick in at just the right time to stop further warming, based on dubious speculation, seems like wishful thinking to me. -
michael sweet at 07:25 AM on 11 December 2010Renewable Baseload Energy
Actually thoughtful, Thanks for the information. We get a mixture of sun and clouds in the summer. From what you say it sounds like systems are being developed. We will have to see how economic they turn out to be. I have heard a lot about GSHP. -
Ice data made cooler
TOP: Yes. Units are not optional. My next version will address a variety of needed display features that you and others have pointed out. Great suggestion on albedo. When I was adding the Methane graph, I thought I should scale it according to it's added greenhouse effect, and then do the same with CO2. I didn't get around to it, but your suggestion on albedo brings the issue to the front. I should try to show a variety of feedbacks. Any one know of a data set with this type of information? One clarification: Do you mean, where albedo is low, more solar radiation is absorbed and reradiated at infrared; and with high albedo, more solar radiation is reflected back into space? jg -
Camburn at 05:33 AM on 11 December 2010A Cloudy Outlook for Low Climate Sensitivity
Thank you dana1981. If 2010 ends with temps of statistical importance, I will agree. It is pretty plain and simple. Good question as to what causes cloud cover to change during the ENSO cycles. There is no question that it does. Finding the cause is more difficult. Has anyone read Sun's paper?
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