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chris1204 at 11:52 AM on 5 April 2011Climate myths at the U.S. House Hearing on climate change
Interestingly, Judith Curry just now happened to give a much more nuanced dissection of Richard Muller's position and evidence at these hearings. Dividing the world into "true believers" and "deniers" is fraught with limitations, impedes communication, and ultimately risks generating coherent responses to the challenges of climate change. -
citizenschallenge at 10:57 AM on 5 April 2011Christy Crock #1: 1970s Cooling
I just noticed my tip of the hat to Scruffy Dan, is missing from the above. http://mind.ofdan.ca/?p=1157 -
citizenschallenge at 10:37 AM on 5 April 2011Christy Crock #1: 1970s Cooling
For a more detailed look at the Global Cooling myth check out this detailed study. http://ams.confex.com/ams/pdfpapers/131047.pdf THE MYTH OF THE 1970S GLOBAL COOLING SCIENTIFIC CONSENSUS Thomas C. Peterson, William M. Connolley, and John Fleck’s "A review of the climate science literature from 1965 to 1979 shows the myth to be false. The myth’s basis lies in a selective misreading of the texts both by some members of the media at the time and by some observers today. In fact, emphasis on greenhouse warming dominated the scientific literature even then." "But perhaps more important than demonstrating that the global cooling myth is wrong, this review shows the remarkable way in which the individual threads of climate science of the time, each group of researchers pursuing their own set of questions, was quickly woven into the integrated tapestry that created the basis for climate science as we know it today." 2. RECOGNITION OF A PROBLEM: THE POTENTIAL FOR WARMING. 3. THE GLOBAL TEMPERATURE RECORDS: A COOLING TREND? 4. ICE AGE UNDERSTANDING 5. CARBON DIOXIDE 6. AEROSOLS 7. MEDIA COVERAGE 8. SURVEY OF THE PEER-REVIEWED LITERATURE "The survey identified only seven articles indicating cooling compared to 42 indicating warming. Those seven cooling articles garnered just 12% of the citations." "Interestingly, only two of the articles would, according to the current state of climate science, be considered wrong in the sense of getting the wrong sign of the response to the forcing they considered. They are one cooling paper (Bryson and Dittberner, 1976) and one warming paper (Idso and Brazel, 1977) and both were immediately challenged (Woronko 1977, Herman et al. 1978)." "As climate science and the models progressed over time, the findings of the rest of the articles were refined and improved, sometimes significantly, but not reversed. " -
calyptorhynchus at 09:16 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Just a side note, another demonstration of why many Australians buy their books from overseas instead of locally. Why should a book cost $10 more in Australia than anywhere else in the world? -
SEAN O at 09:03 AM on 5 April 2011There is no consensus
I like the way Carl Sagan summed it up: "But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown." -
Riccardo at 08:49 AM on 5 April 2011There is no consensus
e doh! Thank you. I think I'm going to use it often ;) -
JMurphy at 08:19 AM on 5 April 2011There is no consensus
That's a good one, e. And, having read your link, I was distracted by another link there : the Chewbacca Defense. I think we have seen that over on the 2nd law of thermodynamics contradicts greenhouse theory thread, including the related Chewbacca Dilemma, as shown by those trying to explain the facts to those who don't seem to be able to understand them ! -
There is no consensus
Riccardo, There's actually a name for this tactic, it's called the Galileo gambit. -
Rob Honeycutt at 07:53 AM on 5 April 2011There is no consensus
Neo... Your post begs the question, where are you trying to keep informed on climate change issues? -
Riccardo at 07:35 AM on 5 April 2011There is no consensus
Actually Galileo is more cited than known. I'd invite to study history a bit more in depth before making any analogy. Should we consider this as a modified version of the famous Godwin's law? -
JMurphy at 07:27 AM on 5 April 2011There is no consensus
Neo Anderson wrote : "As a person who tries to keep informed about the Climate Change issue..." Unfortunately, everything you typed after those words shows that you have failed in keeping yourself informed, except in as much as you seem to have 'informed' yourself via the medium of websites of denial, misinformation and disinformation. However, it is never too late to start, so try these links : Newcomers Start Here The Big Picture List of Skeptic Arguments -
IanC at 06:51 AM on 5 April 2011There is no consensus
Neo, I think you are misinformed on a few of the topics. Regarding you issue with "hide the decline", the decline is not in the temperature record but rather in the divergence in the tree ring record. You'll find a good summary of the issue here The temperature record using modern instruments have shown very good agreement, and have with stood independent reconstructions. See here for details. In fact recently the BEST project ran by Richard Muller, who is hardly pro-AGW, showed agreement with the other temperature series. "The East Anglia emails show the extent that pro-AGW group will go to hide dissent. (The application of pressure on journals to fire editors who dare to publish contrary opinions: the modern day equivalent of burning heretics at the stake)." Here is a good summary of the issue surrounding the allegation. "Look folks it is so complicated that only the truly smart can understand climate change." This cannot be farther from the truth. While some aspects are no doubt highly technical, the theory on the whole is very approachable. What is required is the patience to go though all the details, because a LOT has been done. Most of the skeptics "objections" you hear nowadays is nothing new, and they all have been considered at some point (some long time ago). -
DSL at 06:46 AM on 5 April 2011There is no consensus
Oh, and just in case you are actually human, Neo, perhaps you'd like to read and move your comments to a more relevant thread. -
DSL at 06:43 AM on 5 April 2011There is no consensus
Thanks, Neobot. Of course, the crucial difference is that Galileo had evidence and all the Church had was faith. It's also not so complicated nor so filled with doubt. -
invicta at 06:34 AM on 5 April 2011There is no consensus
NA #285 Thank you. If you spend too much time looking at the evidence for AGW it can sometimes become a little depressing but your post made me laugh out loud. -
Neo Anderson at 06:17 AM on 5 April 2011There is no consensus
As a person who tries to keep informed about the Climate Change issue, I can't help but view the pro-AGW group as the early 15th century Holy Roman Catholic Church, and the anti-AGW group as Galileo. The East Anglia emails show the extent that pro-AGW group will go to hide dissent. (The application of pressure on journals to fire editors who dare to publish contrary opinions: the modern day equivalent of burning heretics at the stake). The same emails indicate that the data is being manipulated to show warming that is no longer occurring. AGW scientist won't/are scared of showing their algorithms, etc… The failure of the pro-AGW groups to have honest and open debates, and the active attacks that this same group perpetrates on scientists with different opinions is more than enough reason to disqualify this science. I know many Christians that are more open to debate and discussion about their religion and faith, than AGW-advocates are about their ‘science.’ As an outsider, I also shake my head with dismay as this whole science has become a moving target over the years. The earth is warming and that's a fact. Oops the upper levels of the atmosphere aren't warming. Ahem, well that is part of our theory, yeah it really was. Oops, only the troposphere at the very lowest levels is supposed to warm. Yeah, that's the ticket. Oops, these temperature levels are declining. Ok, let's manipulate the data to “hide the decline” and attack all the deniers and rename it "Climate Change." Ok, it is going to get so hot, that it really cooling off. Look folks it is so complicated that only the truly smart can understand climate change. Who are the truly smart? Well, they are whoever we say they are. Climate Change is what we say it is. -
Peter Bellin at 06:13 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Another book detailing denialism in the case of lead hazards and chemical prollution: Deceit and Denial, The Deadly Politics of Industrial Pollution, by Markowitz and Rosner. I am thinking of ordering a copy of your forthcoming book for my local library. -
dana1981 at 06:06 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
I was able to get a bit of a preview of the book, and I can confirm, it's quite good. Congrats John and Haydn, well done! -
muoncounter at 05:54 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
les#948: "we pay respect to this great moment by giving up on this assault on the nodal discipline of physics by attempting to prove/disprove another of it's great achievements" That's a great point. Perhaps this will be the year when the deniers swear off the 'I am right and all of physics is wrong' arguments. Out of respect for past great physics achievements ... probably not. But maybe for their own self-respect? -
KR at 05:36 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Anyone interested in this topic of denial might also find Thank You for Smoking worth reading. It's quite a description of tobacco company tactics in denying their product health effects. The movie isn't bad either! -
KR at 05:22 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
L.J. Ryan - If you feel that integrated spectra are not measurements, well, then, I'll pass that on to the spectroscope manufacturers I work with. That should be good for a laugh. "Effective emissivity" is a useful summary of surface temperatures, atmospheric temperatures, band blocking, emission altitudes, and the lapse rate. You get the same results from either orbital measures of emitted spectra compared to surface emitted spectra, or from computationally modelling the entire atmospheric physics. That's the fractional efficiency of TOA energy radiation due to surface temperatures, relative to a black body. Incidentally, do you recognize that the black body temperature required to radiate a fixed power is the absolute minimum temperature required for a gray body to radiate the same power? With the gray body temperature going up as emissivity goes down? I've raised that point a few times with you, but you have not responded. Your objections to this are beginning to consist of nothing but flat denials with no backing; until and unless you post a physical argument that actually makes sense, preferably with references that support it, I don't believe I'll bother replying to any more of your posts. After almost 1000 posts, I believe there's more than enough information present for anyone who isn't sticking their fingers in their ears and singing "La la la la la..." Do some reading, L.J. Ryan, including the sources you yourself have linked to. -
logicman at 05:13 AM on 5 April 2011Arctic Ice March 2011
I would like to thank everybody who has contributed comments to this thread. Yes, everybody. It feels good to have people agree with me, but it takes a contrarian to make me check that I have covered all the bases. Is Arctic ice loss due to natural variation? Patterns of natural variability play a part in Arctic sea ice decline. The Arctic Oscillation is a major atmospheric circulation pattern that can take a positive or negative mode. In its positive mode, it sets up winds that tend to break up sea ice and flush it out of the Arctic, and the thin ice left behind is more likely to melt. In its strongly positive phase in the early to mid-1990s, the oscillation may have made sea ice more vulnerable to summertime melt. Since the late 1990s, however, the Arctic Oscillation has exhibited a more neutral mode, while sea ice has continued to decline. Sea ice decline has persisted through different patterns of precipitation, wind, and local temperature variation. Researchers have found marked declines in sea ice difficult to explain without considering overall Arctic warming. My emphasis. http://earthobservatory.nasa.gov/IOTD/view.php?id=5887 Ice gets younger Based on results of a simple model that keeps track of the age of ice as it moves about on the Arctic Ocean, we show that the areal coverage of thick multi-year ice decreased precipitously during 1989–1990 when the Arctic Oscillation was in an extreme “high index” state, and has remained low since that time. Under these conditions, younger, thinner ice anomalies recirculate back to the Alaskan coast more quickly, decreasing the time that new ice has to ridge and thicken before returning for another melt season. Rigor, I. G., and J. M. Wallace (2004), Variations in the age of Arctic sea-ice and summer sea-ice extent, Geophys. Res. Lett., 31, L09401, doi:10.1029/2004GL019492. http://www.agu.org/journals/ABS/2004/2004GL019492.shtml 'Tropical' heating of the arctic: The first person to write about this effect was George Best. I propose that we should call this the Best Effect in his honor. http://www.science20.com/chatter_box/george_best_elizabethan_climate_scientist Recent Arctic amplification. I have compiled a collection of images and citations for the decade 2001 to 2011 which show the breaking of record after record. Total loss of Arctic sea ice has long been predicted. We are now solidly in the region of, not if, but when. http://www.science20.com/chatter_box/arctic_decade_2001_2011-77700 -
les at 04:38 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
wot? Where's Ryan? I'm expecting something like: You say "Not at all", let me rephrase "yes exactly". Do I understand? Well? -
muoncounter at 04:29 AM on 5 April 2011Arctic Ice March 2011
KL#82: "BP Arctic ice melt due to soot argument and mine are not incompatible." Of course they are not incompatible: You minimize the warming effect of sunlight; he maximizes it. Obviously both are right. Various authors put the BC albedo effect as equivalent to a forcing of between 0.06-0.3 W/m^2. Is that was significant compared to the following? Sphaerica#90, "that still gives open water an albedo that is substantially more than "negligible"" Key point. Here are some comparisons of albedo for a variety of Arctic settings. By far, the worst case (lowest albedo) is the difference between snow/ice (0.65-0.8) and open water (0.07-0.2). That was the problem identified by Serreze et al 2009: This Arctic amplification is largely driven by loss of the sea ice cover, allowing for strong heat transfers from the ocean to the atmosphere. And that is indeed the subject of the Flanner thread, where the equivalent forcing is found to be in excess of 0.6 W/m^2. Worse still, if the predictions in the post are even close, the open water season will be that much longer than in years past. -
les at 04:16 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
961 Ryan. "The physics used to validate GHG theory however, is at odds with this tenet." Not at all. Although I've yet to see much discussion of physics in these posts. Never the less, if it's of help, I refer you, again, to the paper of Prof. Pierrehumbert for illustration. -
L.J. Ryan at 04:05 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
les 958 We agree it must follow. The physics used to validate GHG theory however, is at odds with this tenet. -
les at 03:59 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
addendum: In truth, I can see that when I pointed out that the 2nd law as stated in the blog doesn't hold, it may be read as "the 2nd law doesn't hold"... but, really, that is a bit silly given that I mentioned the "sole result" clause... -
L.J. Ryan at 03:58 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
KR 951 re (A) As I stated, it is not measured. Rather effective emissivity is calculated by solving solving for emissivity with given temperature and power...and the assumption GHG mechanics are correct. So when you calculate for unknown X and then turnaround and use X to calculate one of the given variables, you have simplified verified your formula ([ 240/(0.612 * 5.6704*10^-8 ]^0.25 - 273.15 = 15.2C). The problem is with your given variables. If you are measuring radiation via atmosphere, should not the temperature variable also be that of the atmosphere. Why use temp. from one source and use it to calculate emissivity of another? re(B) I assume the modals would match the data because both assume the wrong input variable..namely surface temperature and atmosphere radiation to measure atmos. effective emissivity. I refer the above reply, why not use atmosphere temperature? KR: I am not damorbel. -
citizenschallenge at 03:50 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Oh and love the cover art, years ago I was playing with a bumper sticker design featuring this same Official Bird of the Republican Party, with a few select words regarding denial and willful ignorance. -
les at 03:48 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
956 Ryan. As mentioned above, everything obeys the 2nd law and the 2nd law states "bla bla sole result bla bla ... " or words to that affect. But now I see you confusion. "another problem" refers to the observations of KR 849. I should have hyperlinked that as the numbering of the comments tends to change from time to time. I must say I can see absolutely no reason to infer from any of my remarks that I believe the 2nd law doesn't hold. The reason for my comment was, on the contrary, to suggest that because the important "sole result" or close system clause is missing from the blog post, many people seem to be very very confused. Be that as it may. Now we have cleared up to your confusion I am confident that you will agree that the green house affect does not violate the 2nd law and we can bring a stop to the physics abuse of this thread. Great! -
citizenschallenge at 03:44 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Thanks John, you've already made my Hero List - I look forward to reading it, to see how many more notches up the list you climb. I sure it will be an excellent time saving resource. I ordered it, do you have any idea how long before delivery can be expected? Oh and thanks for the 20% discount. -
Bob Lacatena at 02:54 AM on 5 April 2011Arctic Ice March 2011
Ken, I stopped responding because you're in clear denial and therefore not open minded in any way, so there is no point to continuing this. Briefly, the simple answer to your geometry question is that we're not talking only about the exact spot of the north pole, but rather the entire area affected by ice. I did err in the 66˚ -- the angle of incidence in the area in question is probably between 30˚ and 38˚, but that still gives open water an albedo that is substantially more than "negligible", so your argument is still moot. More importantly, I'd also point out that your efforts to say that any feedback effects would be trivial are equivalent to saying the same about feedbacks from glaciers, natural CO2 release, methane release, clouds, deforestation, etc., etc. The fact is that that you can make your "ooh, it's so small" argument about any one feedback (except H2O). The problem is that while you can try to argue that the effect of any one feedback is small, the sum of the feedbacks is not not. Many lines of evidence point to the sum of those feedbacks being equal to roughly double the initial forcing. You can't argue that away, and this is a case of a feedback developing before our eyes. The point is that this is a clear positive feedback, it's easily observed, it's something that hasn't happened in many millenia, and it's getting worse -- as per the original post, there is a good chance that this summer will see one of the lowest extents or the lowest extent on record. Denial that the globe is warming is that much more difficult to spew with a straight face as a result. No more on this. It's become silly and repetitive. -
KR at 02:51 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
Moderators - I'm noticing a similarity in approach, in some word choices, and the use of terms I previously used replying to one poster appearing in another; are damorbel and L.J Ryan the same person? We appear to be getting "trolled" again... Please delete this post if I am incorrect. -
L.J. Ryan at 02:50 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
les 955 "This is a statement that the 2nd law only applies to a closed system."...Ok applies only to closed systems "For practical purposes, the system which consists of: the sun, outer space, the solid earth and the earths atmosphere is not a closed system. "...Ok the earth's system is not closed These together suggest you are saying the earth's open system does NOT have to follow the 2nd law. Otherwise, why would have "another problem" or for that matter the entirety of 914? -
soo doh nim at 02:43 AM on 5 April 2011Debunking Climate Myths from Politicians
If memory serves, there was something similar to the Oregon Petition "debunking" evolution. The response from the biological community was "Project Steve": http://www.ncse.com/taking-action/project-steve. Perhaps something similar from the climate community would be appropriate... -
les at 02:21 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
954 Ryan I meant" The "2nd law" objection to the greenhouse effect is based upon a mistaken notion.." I don't disagree with you. However I'd like to suggest there is another problem. In the post, the statement of the 2nd law has missed out the phrase: "whose sole result". This is a statement that the 2nd law only applies to a closed system. For practical purposes, the system which consists of: the sun, outer space, the solid earth and the earths atmosphere is not a closed system.
HTH. I even already posted another phrasing of the same point from here"The planetary warming resulting from the greenhouse effect is consistent with the second law of thermodynamics because a planet is not a close system"
what bit are you struggling with? -
L.J. Ryan at 02:11 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
les 953 So when you said:884 KR
What did you mean?
" The "2nd law" objection to the greenhouse effect is based upon a mistaken notion.." I don't disagree with you. However I'd like to suggest there is another problem. In the post, the statement of the 2nd law has missed out the phrase: "whose sole result". This is a statement that the 2nd law only applies to a closed system. For practical purposes, the system which consists of: the sun, outer space, the solid earth and the earths atmosphere is not a closed system. -
les at 01:32 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
949 Ryan. You can paraphrase what you like. But I would rather advise learning the meaning of the orriginal phrasing, put together by better physicists than you or I. But you really should not invent things like that that is my "revised position". I revised nothing. And you really cannot put a paraphrase into quotation marks! Yes, clearly the 2nd law is universal. But it doesn't say that energy can not flow from cold to hot. it says that energy can not flow from cold to hot without work being done. Any one who doesn't realise that should get a cold beer from the fridge and think about it. -
Albatross at 01:22 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
Congratulations on the book John, very exciting. I'm sure that it will inform many people and offer valuable insights. I have added it to my B'day wish list for the family :) I'll send this URL along to some interested parties (including 'skeptics') who might consider buying it. -
Alexandre at 01:17 AM on 5 April 2011Upcoming book: Climate Change Denial by Haydn Washington and John Cook
The table of contents looks really interesting. Ordered and looking forward to checking it out. -
L.J. Ryan at 01:17 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
CBDunkerson 950 I should have addressed my post to les 948 & 914...914 is linked within 948. -
Albatross at 01:16 AM on 5 April 2011Arctic Ice March 2011
Moderator's, perhaps all future comments along the lines of "the ice loss is not significant for the earth's climate system", and all associated correspondence should be moved to a more appropriate thread? And if people insists with following this line of reasoning here, their should be deleted. Fell free to delete this once read. -
Albatross at 01:13 AM on 5 April 2011Arctic Ice March 2011
Actually, muoncounter @80 makes an excellent point. BP is trying to claim that most of the ice loss was from albedo effects arising from soot. Here other claims are being made, while at the same time making the incredibly weak argument that the dramatic Arctic ice loss to date (and in the future), is of little consequence. Thank you John, Ken and BP for showing the incoherence, inconsistencies and sometimes contradictory nature of arguments used by "skeptics". CBDunkerson summarises the salient points in their post at 85-- Thanks CB. Now maybe it is time to ass Ken the same question that I asked JohnD @79: "This thread, again, is essentially about the upcoming Arctic se[a] ice melt season. Do you [Ken] have anything specific to say about that? Is the sea ice minimum this year going to be greater or smaller than 2010? Please substantiate your answer with evidence as logicman has done." Thanks too Tom for your comments refuting yet more BS from 'skeptics' (does it ever end?). -
Albatross at 01:05 AM on 5 April 2011Arctic Ice March 2011
Ken, "Sphaerica has not responded to claim that my schoolbook planetary geometry is wrong - nor has anyone else." With respect I have personally decided not to do so b/c I am trying not to send this thread even further off topic. -
KR at 01:05 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
L.J. Ryan - "To claim effective LW emissivity of 0.612 is measured, is specious. How do measure “effective emissivity”? " That's quite a statement you're making there, L.J., and quite unsupportable. (A) The effective emissivity is quite simply measured by looking at the surface temperature (well known, well measured, etc., not to mention being what we're interested in) and the integrated power emitted at the top of the atmosphere (about 240 W/m^2). The tool used for those measurements is an infra-red spectroscope, incidentally. That's about 61% of the power that a black body at 15C would radiate, and hence the effective emissivity is 0.61. (B) That number matches the physics, as per line-by-line spectral modelling of the atmosphere such as in the MODTRANS and more up to date computations. It's always nice when the model matches the data - it's excellent support for the model being correct. So - that's the data, and it's supported by the (correct) models. You also have stated that "Delta T must be a function (of) a non-radiative input", rather than the well understood greenhouse effect. Just what non-radiative input would that be??? Invisible volcanos? Little green men? Accumulated friction from the hand-wringing of climate skeptics? I quite simply cannot take your argument seriously when you invoke Mysterious Unknown Forces (MUF's) as a replacement for the last 150 years of science. Please, L.J.Ryan - read some of the references you have equation-mined. Learn a bit more about the science. You're approaching the issue with a lot of erroneous preconceptions, and those are leading you to incorrect conclusions. -
CBDunkerson at 00:49 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
L.J. Ryan, you 'quote' the phrase "closed loop system" twice in your comment above, yet I cannot find it anywhere in the preceding comments. I assume this is meant to be a reference to comments about over-simplified versions of the 2nd law of thermodynamics (e.g. 'energy can only flow from hot to cold') only being applicable to 'closed systems'. The 2nd law of thermodynamics is universal (so far as we know)... however, poorly stated versions of it require qualification. -
Tom Curtis at 00:41 AM on 5 April 2011Arctic Ice March 2011
Just to put Ken Lambert's line of argument into perspective, the additional 0.01% of the Earth's surface that is exposed ocean rather than ice in the Arctic due to warming over the last 30 years absorbs an additional 1.34 * 10^22 Joules of energy each summer. That in turn is enough to melt 4 * 10^13 tonnes of ice, or 14 million square kilometers of sea ice with an average depth of 3 meters. That is nearly three times the extent of sea ice at the minimum in 2007, and more than two times the extent at the minimum of 2011. Of course, not all the ice is melted because much of the energy escapes to space rather than being used to melt ice. But Lambert's implied suggestion that because only a small part of the Earth's surface is effected, therefore the energy involved is inconsequential is simply false. Further, once the entire cryosphere is considered, the implied suggestion of little global impact is also shown to be false by Flanner et al, with the total NH cryosphere feedback representing about 80% of the initial GHG forcing over the last 30 years. -
CBDunkerson at 00:25 AM on 5 April 2011Arctic Ice March 2011
It seems clear that the decline in Arctic ice volume (both land and sea) is being driven by a combination of factors; the same increased greenhouse warming impacting the entire planet (though somewhat higher here since carbon maps show northern hemisphere and polar CO2 levels frequently higher that other regions), additional warming due to changes in albedo as ice melts, additional warming due to changes in ocean currents bringing in more heat from the tropics, increased transfer of ice out of the Arctic due to loss of ice blockages and stronger currents, et cetera. Thus, I'm not really seeing the importance of the whole 'how much impact does albedo change have' debate. Theoretically, this should actually be the easiest factor to quantify (as the study Tom Curtis cites seems to have done)... but regardless of whether these albedo changes are causing 5%, 10%, 25%, or whatever of the ice loss... the ice is still being lost. Once it is gone we will still see profound changes in ocean currents and weather far beyond the bounds of the Arctic. Hence, I'm failing to see the point. -
L.J. Ryan at 00:21 AM on 5 April 20112nd law of thermodynamics contradicts greenhouse theory
les 948 Let me see if understand your revised position on the GHG physics and the 2nd law. I paraphrase you (maybe): Because the earth's radiative energy system is not a "closed loop system" and the 2nd law applies only to "closed loop systems", GHG physics therefore does not follow nor is required to follow the 2nd law. Do I have this right? -
Tom Curtis at 23:55 PM on 4 April 2011Arctic Ice March 2011
Ken Lambert @83 As pointed out in my preceding post, the loss of the complete ice cap would expose 15 times as much water as has been exposed by the increased summer melts over the last 30 years. 15 * 2.8% = 42% (the 43 being a consequence of slightly different roundings). For the snow, approximately 12% of the Earth's surface lies north of 50 degrees North. The average insolation in spring in the NH at those latitudes is of the order of 200 w/m^2. I estimated the change in albedo from snow to earth as being about 0.4, which is very conservative, although treating all areas north of 50 north is, of course, not. That yields a ball park figure of 0.8 w/m^2 globally averaged. (In truth the land area effected by reduced snow cover is significantly less than used in my calculation, but then the effect is evident for significantly more than the one month I allowed, so the figure is a reasonable indicator of the magnitude of the effect.) The 0.63 w/m^2 comes from a scientific study that broke the effect down cell by cell, month by month from actually measured data. There is no ball park involved in that study, but there is an uncertainty, with bounds of 0.33 to 1.07 w/m^2. Follow the link provided for more detail. As you noted, the area enclosed by the arctic circle, which you noted is at 66.4 degrees North, is about 4.4% of the Earth's surface. However, not all land north of 50 degrees north is within the arctic circle. Why are you assuming that only forcings within the arctic circle itself have contributed to polar amplification? Finally, I can make a reasonable estimate of how much of incident solar radiation is absorbed by arctic oceans because the laws of physics do not change with latitude. Ergo the emissivity of arctic oceans closely matches those of oceans everywhere, and though the low angle of incidence does increase reflectivity, it is overall a minor effect. Bear in mind that even tropical oceans have sunsets and sunrises, and that in consequence they have high angles of incidence for only a short period of every day.
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