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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 89901 to 89950:

  1. Upcoming 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!
  2. 2nd 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?
  3. Upcoming 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!
  4. 2nd 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.
  5. Arctic 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
  6. 2nd 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?
  7. Arctic 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.
  8. 2nd 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.
  9. 2nd 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.
  10. 2nd 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...
  11. 2nd 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.
  12. citizenschallenge at 03:50 AM on 5 April 2011
    Upcoming 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.
  13. 2nd 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!
  14. citizenschallenge at 03:44 AM on 5 April 2011
    Upcoming 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.
  15. Bob Lacatena at 02:54 AM on 5 April 2011
    Arctic 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.
  16. 2nd 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.
  17. 2nd 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?
  18. Debunking 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...
  19. 2nd 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?
  20. 2nd law of thermodynamics contradicts greenhouse theory
    les 953 So when you said:

    884 KR
    " 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.

    What did you mean?
  21. 2nd 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.
  22. Upcoming 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.
  23. Upcoming 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.
  24. 2nd law of thermodynamics contradicts greenhouse theory
    CBDunkerson 950 I should have addressed my post to les 948 & 914...914 is linked within 948.
  25. Arctic 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.
  26. Arctic 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?).
  27. Arctic 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.
  28. 2nd 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.
  29. 2nd 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.
  30. Arctic 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.
  31. Arctic 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.
  32. 2nd 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?
  33. Arctic 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.
  34. Arctic Ice March 2011
    Tom Curtis #81 I am glad your calculation agrees with mine that the effect of arctic ice melt is trivial (2.8% increase in arctic forcings since 1978). The leap is then made to 43% with a loss of the 'ice cap' - presumably the summer sea ice disappears entirely. So how then is the leap made to one month earlier snow melts down to 50 degrees north and 0.63W/sq.m? And all this from an area of the Earth's surface of less than 4.4%?? What about the effects on the other 95.6% of the Earth's surface, like the 70% occupied by the oceans where we still can't find the absorbed heat. Last time I looked there were hardly any Argo buoys above 60 degrees north, so what monitoring of ocean temperatures are we relying on to measure the solar energy absorbed in the Artic ocean?
  35. Arctic Ice March 2011
    muoncounter #80 The BP Arctic ice melt due to soot argument and mine are not incompatible. Tell us what is the average albedo of ocean surface at an average Arctic angle of incidence of 23.4 degrees, and what is the albedo of sooty snow and ice at similar angles of incidence? It seems that Sphaerica made the claim that I was talking gibberish and he (she) was sure that the Arctic ice melt was due to insolation higher than the tropics with a sun incidence angle of 66 degrees at the North Pole. I simply pointed pointed that this was wrong in fact. Sphaerica has not responded to claim that my schoolbook planetary geometry is wrong - nor has anyone else. Johnd makes salient points about heat flows affecting Arctic melt.
  36. Soot and global warming
    Some perspective on the LIA : However, the timing of maximum glacial advances in these regions differs considerably, suggesting that they may represent largely independent regional climate changes, not a globally-synchronous increased glaciation (see Bradley, 1999). Thus current evidence does not support globally synchronous periods of anomalous cold or warmth over this timeframe, and the conventional terms of "Little Ice Age" and "Medieval Warm Period" appear to have limited utility in describing trends in hemispheric or global mean temperature changes in past centuries. Mann et al. (1998) and Jones et al. (1998) support the idea that the 15th to 19th centuries were the coldest of the millennium over the Northern Hemisphere overall. However, viewed hemispherically, the "Little Ice Age" can only be considered as a modest cooling of the Northern Hemisphere during this period of less than 1°C relative to late 20th century levels (Bradley and Jones, 1993; Jones et al., 1998; Mann et al., 1998; 1999; Crowley and Lowery, 2000). Was there a "Little Ice Age" and a "Medieval Warm Period"?
  37. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    PS: I just bought the book.
  38. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Marcus @ 13: "Once more, HR, you seem to be full of denialist clap-trap. Try to do better next time please." Might I suggest, "More light, less heat" or "lighten up" [puns intended]. Meanwhile, heartfelt congratulations John on what has clearly been a labour of love.
  39. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    'Grats on your book, John. Now I'll have to see if my wife will let me buy a copy. ;)
  40. Soot and global warming
    thingadonta, you'll notice that we are not currently >in< the 1950s... or even 20 years thereafter. Any impact of that solar forcing or feedbacks set off by it are long gone. Atmospheric carbon dioxide was level at 270 +/- 10 ppm for thousands of years until ~1800. Then it started increasing. Thus, the optimal time to compare current temperatures against would be ~1800. That said, all three of the major temperature anomaly records start in 1850 or 1880... because we don't have significant thermometer readings before then. No "agenda" involved. Just using all the data we have available. Thus, the available anomaly records are technically not "pre-industrial"... they pick up after the first 10 - 15 ppm of CO2 increase. However, this is close enough that people are usually referring to the warming shown in those records when they say 'pre-industrial'. In essence, the current ~0.75 C total warming anomaly generally cited leaves out the small amount of warming from 1800 - 1880 caused by industrial greenhouse gas emissions. In any case, the accusation of "ideological" selection bias is pure nonsense... 1880 was long after the Little Ice Age and obviously 'chosen' based on the fact that it is the data we have.
  41. funglestrumpet at 21:15 PM on 4 April 2011
    Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    2 Meikol. Ok, so you agree that Climate Change is a fact. Why then are you and all those like you so intent on thwarting action to counter it? You might be in some doubt as to the origin of an asteroid headed for the earth, but would you really thwart action until we could be absolutely certain of its origin? No, of course not. But there again, there would no vested interests in having an asteroid hit the earth. The same cannot be said of Climate Change. Get your calculator out and try entering '2' then hit '+' and then another '2'. The answer will probably surprise you. As for the book, I hope it is the success it deserves to be.
  42. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    "A warmer Earth in any case will lead to less differences in climate, which means that there will be less, not more changes (once things have changed for better or for worse)." Lets *assume* for 5 seconds you're correct-though you're probably not. What impact do you think a lack of variability in climate is going to have on our crops? Once again I see the Denialist crowd speak without actually thinking.
  43. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    "Do you contemplate the existence of a warmist industry" So, tell us HR, who is *really* going to benefit from this supposed "Warmist" industry? After all, we *know* what the fossil fuel industry has to lose if climate change mitigation takes place, but I don't see a lot of scientists getting rich from predicting climate change. Once more, HR, you seem to be full of denialist clap-trap. Try to do better next time please.
  44. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Congratulations to the Authors. One small recommendation: Given what 10 Bern noted, along with the discount, may I suggest you include a months worth of some general purpose SSRIs? This would enable inhabitance of the deniosphere to read the book, increasing your potential readership by at least 1%.
  45. Anne-Marie Blackburn at 20:35 PM on 4 April 2011
    Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Congratulations John! Now the question is, when will you be touring the UK so I can get you to sign the book? Cornwall is beautiful :)
  46. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    I can't believe the "It's not us" and "It's not bad" memes both appeared in the first 10 comments! Back on topic - congrats on the book, that's a real achievement. Shame it's 40% more expensive here in Oz than the US price (but I've seen some books where the difference was over 150%, so 40% isn't too bad. :-)
  47. Soot and global warming
    Sorry, that should read "20 year time lag from solar effects", and also "cloud cover changes which are both immediate and delayed", and "it was colder than the average over the last 10,000 years during the immediate pre-industrial period". (So don't chose it as a baseline!) I'll try to spell check next time.
  48. Soot and global warming
    "Since solar forcing is actually negative compared to the baseline that means the warming from greenhouse forcing is actually >greater< than the total warming observed thus far." No, solar activity gradually increased from around 1800-1950, meaning the solar forcing would continue until at least then. On top of this, you get at least a 20 year time lag from soal effects, which has been shown by various research papers. There are also could cover changes which are immedaite and sloightly delayed. Aside from this, the reason I mentioned 1700 rsther than 1800 as pre-industrial T is because of the very reason I outlined, 'baseline' should not be chosen irrespective of the relative natural climate at the time, which just happened to be very cold-Littel Ice Age (LIA). The LIA bottomed earlier than 1800. Also, if oen takes into account natural factors, baseline should be ~1950, because it was naturally colder than average over the last 10 years during pre industrial period. You dont chose as a baseline something well below a running mean unless one has an agenda, the very fact that the European Climate Union (or whatever they call themselves) chose this date is largely ideological, it has nothing to do with optimal temperatures, effects of industrualisation, or a running mean upon which to use as a baseline against human activities.
  49. 2nd law of thermodynamics contradicts greenhouse theory
    947 - Glenn. Nice article link. As an aside, and of only the slightest relevance to this blog post, I note his statement "The planetary warming resulting from the greenhouse effect is consistent with the second law of thermodynamics because a planet is not a close system"... as noted above and to which 934 Ryan should have assumed I was alluding. Now, I suggest that as, as noted by the Economist, this is the 150th anniversary of some relevant and great physics (the unification of Electric and Magnetic fields) - 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 (the laws of thermodynamics) through bean-counting and pseudo-modelling.
  50. Glenn Tamblyn at 19:19 PM on 4 April 2011
    2nd law of thermodynamics contradicts greenhouse theory
    Fred "If we make the simplifying assumption of an effective emission level in the atmosphere, this fixes the outgoing radiative temperature (at 255K as it happens). Anything which increased that temperature would increase outgoing radiation, and the atmosphere would cool down. Anything which reduced that temperature would have the opposite effect." You are missing several factors here Fred. As GH Gas levels increase, then the altitude at which emitted photons have a clear path out to Space increases. With altitude Temperature decreases so the emission temperature decreases so less radiated because the altitude of radiation increases. To use a simple analogy, its like a Cloud Bank. At the bottom of the 'cloud' a photon can 'see' the ground so can reach it. At the top of the 'cloud' a photon can 'see' Space and can reach it. One of the two effects of increased GHGas levels is to increase the upper altitude of the 'cloud'. So when a photon can reach Space it will be emitted from air that is colder. There is an excellent article on the radiative physics of the GH Effect by Prof Ray PierreHumbert in Physics Today here http://geosci.uchicago.edu/~rtp1/papers/PhysTodayRT2011.pdf Have a look at his figure 3a, modelled and measured spctrum of radiation leaving the Earth. At around wavenumber 670, right in the highest absorption region for CO2, the amount of energy reaching space spikes up. Right in the middle of the highest absorption part of the CO2 band the emission temperature spikes back up! Why? Because the altitude at which the path to Space at that wavenumber is clear because of the high levels of absorption is SO high that it is above the altitude where lapse rate causes a temp drop with altitude and is high enough that atmospheric temps are climbing in the upper stratosphere. The models of radiative transfer are so accurate that they capture this altitude dependent temperature behaviour superbly. That graph is a thing of transcendent beauty.

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