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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 90201 to 90250:

  1. 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 :)
  2. 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. :-)
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. Glenn Tamblyn at 19:03 PM on 4 April 2011
    2nd law of thermodynamics contradicts greenhouse theory
    Wow. Comment 945 and counting! Not to intrude too much on everyones fun, but a few questions for Fred: "From the source, surface, to the sink, atmosphere, most of the energy transfer is via conduction, convection and evaporation." Source please! Radiation transfer from an object at temerature x is determined only by its temperature, not other parallel heat transfer mechanisms. "and the simplistic “back-radiation” theories of AGW are wrong. ". Oops. Small problem here Fred. Back Radiation has been observed for decades and has been increasing in the radiation frequencies of the GH gases. Damn pesky thing observations aren't they. A beautiful theory derailed by a mere observation. "That is why we must use the net transfer of energy to the atmosphere, e 873, from the surface, and not the back transfer (the negative term in Stefan Bolzmann) to calculate any possible GHG effects" Wrong Fred. Yes the net of the two flows will be what determines (is) the actual energy flux. However this is made up of several different phenomena that occur because of different mechanisms. Radiation flux from the surface is driven solely by surface temperature. Absorption by the atmosphere depends of the absorption properties the GH gases alone. Back Radiation depends on the temperature of the lower atmosphere at an altitude where the path back to the surface is not 'optically thick'. Several phenomena coming together to create the GH Effect, rather than the GH Effect being caused by the net of the heat flux.
  8. Soot and global warming
    Thingadonta: "Why is the benchmark for T 'pre-industrial levels'..." We should determine the total change in temperatures caused by industrial carbon dioxide emissions from some point other than when those emissions started? Which, by the way, was around 1800... not 1700. On the whole, 'earlier temperature changes were caused by the Sun' bit... temperature forcings from solar fluctuations are obviously temporary. When the solar output changes the forcing 'goes away'. Thus, if solar forcing were currently equal to the 1800 level then none of the current cumulative temperature change would be due to the Sun. 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.
    Moderator Response: [Dikran Marsupial] I suspect the 1700 startpoint is because of land use changes, which are as much industrial as agricultural (particularly iron smelting - for which coke was also used in the 18th century).
  9. Soot and global warming
    Does anyone know why West Europe is not included in the figure? I think I've tracked down 'Bond et al. 2000' (poor referencing there) to "A technology-based global inventory of black and organic carbon emissions from combustion. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109" but that does not break down the geographic units in the same way as the figure does (e.g. Europe is taken as a whole and North Americas is not split into the US & Canada as in the figure).
  10. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Many congratulations John. Sounds like a very interesting read.
  11. 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).
  12. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Well done, John, and thanks for the discount offer!
  13. Philippe Chantreau at 16:13 PM on 4 April 2011
    Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Congrats John, I'm sure you had no shortage of material to write about...
  14. Soot and global warming
    "....necessary to keep global temperatures from rising more than 2°C above preindustrial levels in the next 50 years" Why is the benchmark for T 'pre-industrial levels', when this time period (ie around 1700) was the amongst the coldest in the last 10,000 years?, ie the Little Ice Age? Shouldn't a T baseline be when c02 effects on T apparently became stronger?, such as from about 1950? Using 'pre industrial T' as a baseline might appeal to ideological conveniences (if one is anti-industry, anti-caplitalist, anti-fossil fuels, pro-socialist control, pro-alternative energy etc etc), but it is generally scientifitcally accepted that most of the warming from ~1700-1950 was caused by the sun, not by human industrial activities. Moreover, the T at 'pre industrial levels' could be argued to be not the most optimal for human and ecological health, (there is no real 'optimum' in any case); in terms of human health, optimum T is certainly a little warmer than Little Ice Age conditions, so neither such a temperature, nor climate period, should be used as a baseline for social objectives.
  15. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Denial is a fact. What is causing it is a bit of a greay area, but maybe if I read some books on it I might have a better idea....
  16. 2nd law of thermodynamics contradicts greenhouse theory
    KR You said : However, you make the (false) assumption that this power level is a boundary condition on the surface. and T = [ P / ( ε * σ ) ]^0.25 K [ 240/(0.612 * 5.6704*10^-8 ]^0.25 - 273.15 = 15.2C from where does the P (240W/m^2) LW originate....the surface? This very flux is the sole source of LW...without the 240 W/m^2 of SW input the there will be no LW. So save changes to albedo or solar radiation, this IS a boundary condition for radiative energy. Said otherwise, because P input to the surface must equal P output at equilibrium...you can not get more LW flux out then SW flux in. Re-radiating Pout can not increase Pin. Delta T must be a function a non-radiative input. To claim effective LW emissivity of 0.612 is measured, is specious. How do measure “effective emissivity”? Emissivity with the qualifier effective, only aids in obfuscation. “Don't bother looking a the real mechanics of GHG physics, it can all be explained by effective emissivity"
  17. HumanityRules at 15:01 PM on 4 April 2011
    Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Danno beat me to it! "This is most obvious in the denial industry ......" Do you contemplate the existence of a warmist industry????? Congrats as well.
  18. David Horton at 14:59 PM on 4 April 2011
    Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Congratulations John.
  19. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    Climate change is a fact. What is causing it is a bit of a grey area.
  20. Upcoming book: Climate Change Denial by Haydn Washington and John Cook
    "Obviously you've created this site just so you can make money from selling books!!! CONSPIRACY!!!!" Congrats on the book John, I hope it's a success.
  21. Muller Misinformation #1: confusing Mike's trick with hide the decline
    TTTM has quite some faith in CA I see. I wonder if he has read this and checked the CA version against the originals.
  22. michael sweet at 12:35 PM on 4 April 2011
    It's cooling
    Eric, We can agree that Harp seals appearing in small numbers in the Northern USA are not an indication of global cooling.
  23. Muller Misinformation #1: confusing Mike's trick with hide the decline
    TTTM@118 I recommend a website called Skeptical Science. it contains all the information you need to educate yourself on the subject of climate change. As for you accusation of censorship, complete nonsense. People here are allowed to present any evidence they like so long as it is on topic and not an accusation of fraud. Pick any thread you like as evidence of this. I recommend Meet the Denominator and The greenhouse effect and the 2nd law of thermodynamics to see just how accommodating the Moderation Policy is if followed. If you continually run afoul of it then the problem lies with you.
  24. Arctic Ice March 2011
    Ken Lambert @73, based on the third chart in Daniel Bailey's post @43, the average summer sea ice has retreated just over 2 degrees of latitude over the last 30 years. At the latitude of the limit of summer sea ice, that represents an additional 0.01 percent of the Earth's surface in which sunlight is falling on ocean rather than ice. Allowing for the exposure time of only about three months, and arctic summer insolation of around 500 w/m^2, and a change of albedo from 0.9 to 0.1, reasonable ball park figures, that represents a globally averaged forcing of 0.01 w/m^2 or just 1.25% of the equivalent change in greenhouse forcing over the same period. Complete loss of the ice cap would expose about 15 times as much ocean to direct sunlight, resulting in about 0.15 w/m^2 globally averaged, or about 8% of the change in CO2 forcing since the start of the industrial era. Obviously, globally averaged these effects are trivial. They do, however, represent a significant increase in regional forcing in the arctic. The regional increase from the melt since 1978 represents a 2.8% increase of forcings within the Arctic Circle; while the loss of the Ice Cap would represent a 43% increase in regional forcing. The small area within the arctic circle to which you allude means the small globally averaged effect of arctic ice melt has a correspondingly large regional effect, and is shown to be a significant factor in arctic amplification. What you are neglecting in terms of global effect is the consequence of early snow melts over northern latitude lands. A rough calculation shows that a one month earlier snow melt down to about 50 degrees latitude will result in a forcing comparable to the change in green house forcing over the last 30 years. These are just ball park figures. A more detailed analysis was made by Flanner et al who estimate that combined ice and snow effects result in a forcing of around 0.63 w/m^2 over the last 30 years, or nearly 80% of the greenhouse gas forcing over the same period. This discussion, if important, should probably continue on the thread discussing that paper.
  25. Soot and global warming
    cbrock the point you miss is that unlike all other alpine glaciers where summer snowfall is modest and dust and particles accumulate on the surface and enhance melt, summer monsoon dominated glaciers have there main accumulation in the summer with nearly daily snowfall burying the soot so it cannot accumulate at the surface. It is not that complicated, but nor can we extrapolate the same process from all glaciers. If we go further north into Tibet monsoon accumulation is not nearly as important and soot can have a role.
  26. The Climate Show Episode 10: David Suzuki and the sun
    I know I've made the point previously, but the graphs showing warm nights / warm days, and winter/summer warming, suffer greatly from the use of a modern reference period. If you zero both graphs back at the beginning of the plotted period, you get a much better feel for what the difference between the trends really is. As they stand now, a casual observer might think "what's all the fuss about, they're fairly close together in recent years". Other than that - I saw all the graphics on the hot-topic website in the show notes, except that first screen cap from the video - it tells one of the most important parts of the story, might be a good idea to get Glenn to add it there, if he hasn't already. Another good rebuttal, though, and a good show in general - sad about the loss of the video, it really does make it more enjoyable to follow along. The interview with David Suzuki was good, though!
  27. Muller Misinformation #1: confusing Mike's trick with hide the decline
    "Mike’s Nature Trick was originally diagnosed by CA reader UC . . ." If "UC" has discovered compelling evidence of scientific fraud, I'm sure he or she has published the results in a peer-reviewed journal. Perhaps Tim would provide a link.
  28. Arctic Ice March 2011
    Albatross#79: "The obfuscation and dissembling continues" We're actually in the midst of an obfuscation cross-fire. On this thread, friend KL declares that solar input to the Arctic is limited by geometry; based on this irrefutable argument, the sun can't be a significant factor in either warming the Arctic Ocean or melting ice. Over on the soot thread, friend BP declares that soot, with its known capacity for absorbing energy, is responsible for melting Arctic ice. Which is it? Does the denier left-hand know what the denier right-hand is thinking? Or will this apparent conflict cause the deniersphere to implode?
  29. Arctic Ice March 2011
    Johnd, The obfuscation and dissembling continues. As for you opining "The comment made by someone else earlier regarding considering the Arctic as an airconditioning system, this analogy can only be applied by acknowledging the fact that an airconditioner works by first removing hot air." Please show some respect, that "someone else" was in fact Dr. Meier from the NSIDC--someone who in all likelihood knows more about the Arctic and the earth's climate system than you or Mr. Lambert could ever hope or dream to know. You of course have now elected to try and dissemble that statement in an attempt to fabricate more faux debate and to detract from the inconvenient loss of Arctic sea ice. If you want to talk clouds then take that to another thread (I have suggested the Flanner thread @ 77)--but ignoring or belittling the important role of lowering of albedo in the Arctic arising from the reduction in the snow and sea ice cover associated with AGW is not helping your cause or credibility. This thread, again, is essentially about the upcoming Arctic se ice melt season. Do you 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.
  30. 2nd law of thermodynamics contradicts greenhouse theory
    Fred Staples @939, first let me surprise everyone and congratulate you on being almost entirely correct. I notice that you indicate that: 1) The effective temperature of the outgoing radiation is 255 K; 2) That the effective altitude of radiation to space is about 5 km. From these it follows that 3) The (average) temperature of the atmosphere at about 5 km is about 255 K. You also note that: 4) The lapse rate (in the troposphere) is entirely determined by the local gravitational accelerationg, g, and the specific heat of the atmosphere; and that 5) The lapse rate is approximately 6 degrees per km (6.5 is more accurate). Therefore: 6) The average surface temperature is (5 * 6.5) + 255 = 288 K. That is the greenhouse effect in a nutshell. To see this, consider an example in which the atmosphere absorbs (and radiates) no IR radiation. In that case the effective altitude of radiation to space would be 0 km, and hence the surface temperature would be (0 * 6.5) + 255 = 255 K. It is not the lapse rate, therefore, which is responsible for the elevated surface temperatures, for it is (near) constant in both scenarios. Rather it is the presence of IR absorbing and radiating gases in the atmosphere. We can consider the case where the concentration of GHG in the atmosphere decreases. This will lower the effective altitude of radiation to space, and consequently lower the surface temperature (but not the effective temperature of radiation to space). Conversely, if we increase the concentration of GHG, that will raise the effective altitude of radiation to space, the surface temperature will rise, all else being equal. Hence, from principles you have just espoused, the green house effect follows by simple logic. Back radiation does come into the picture. Without the return of some energy from the atmosphere to the surface, thus reducing the net transfer of energy from surface to atmosphere, an increase of the Earth's surface temperature would be impossible. But that transfer (in keeping with the 2nd law of thermodynamics) can never exceed the energy transfer from the surface to the atmosphere (except locally and temporarily). If it rises to a level which would warm the surface by more than the amount indicated by the lapse rate and the effective altitude of radiation to space, the result is simply an increase of of convection and evapo/transpiration, thus nullifying the effect.
  31. Peter Hogarth at 09:02 AM on 4 April 2011
    Soot and global warming
    Berényi Péter at 04:14 AM on 4 April, 2011 You need to read a fair slice of the recent peer reviewed literature to gain a better picture. Your proposed correlation of Arctic Ice reduction and soot from China does not correspond to the actual data from the Arctic. Overall amounts of Black Carbon has reduced in the Arctic in the past few decades. We discussed this here in 2010 where I gave several references from 2009 and 2010. Obviously more work has been done since and here are some further references from 2011. Matsui 2011 shows Russian Biomass Burning is still the most important source of Black Carbon in the snow in the North American Arctic, in agreement with previous studies, whilst Skeie 2011 shows using a model cross checked with an assembly of recent measurements, with emphasis on the Arctic, that Black Carbon reached a measured peak in the 1960s, falling off since, and interestingly (as mentioned before) also reached relatively high levels in the 1920s.
  32. Arctic Ice March 2011
    Ken Lambert at 00:38 AM, your quantifying of the various factors, area, insolation etc, have been effective counters to the emotional rhetoric that normally drives such debates. All the calculations you've done can be summed up by comparing the average situation as what is represented at the equinoxes, whereby the near polar regions have a nett energy deficit of about 200 w/m2, whilst the near equatorial regions have a nett energy surplus of about 200w/m2. The comment made by someone else earlier regarding considering the Arctic as an airconditioning system, this analogy can only be applied by acknowledging the fact that an airconditioner works by first removing hot air. In the planets "air conditioning" system this comes about by the flow of heat towards the equatorial regions. Because of the high cloud cover along the equator most heat is liberated from areas just north and south of the equator, where there are fewer clouds, and cloud cover is more variable. Thus irrespective of what angle the issue of Arctic ice is looked at, it is either clouds over the Arctic regions that control incoming solar radiation, or clouds along the near equatorial region that control the liberation of outgoing heat from the system that plays the major role. This is merely reflected by the polar regions, being controlled by a "knob" that is not in the polar regions.
  33. 2nd law of thermodynamics contradicts greenhouse theory
    A tiny Excel exercise for L.J.Ryan and others: Create a new spreadsheet. Enter the values below: A1: 1.0 A2: A1-0.01 Copy A2, paste from A3 to A50. B1: =(240/(A1 * 5.6704*10^-8 ))^0.25- 273.15 Copy B1, paste from B2 to B50. Explanation: With 240 W/m^2 (fixed) radiated as power, and varying emissivities, what gray body temperature (in degrees C) is required to radiate that 240 W/m^2, using the Stefan-Boltzmann relationship? An emissivity of 1.0 represents a perfect black-body, 0.98 represents the Earth's surface with no GHE, and an emissivity of 0.61 is quite interesting.
  34. Soot and global warming
    mspelto- I think the primary mechanism of depositing soot onto the Himalayan glaciers is snowfall, known as "wet deposition". This is in contrast to "dry deposition", which is particles impacting the surface and sticking. Wet deposition is a very efficient process, as ice crystals may form on soot particles, and falling snow can also capture soot on the way down. Thus the main "accumulation zones" are probably also where most of the soot is found. During a thaw cycle, the top layer of snow melts and the water runs down into the snowpack, leaving the soot behind. The accumulated result of many such cycles can be an increased concentration of soot at the top of the snowpack--it can get concentrated there. So I wouldn't expect the main effect of the soot to be limited to the terminus of the glacier. The important thing about soot in snow is that it doesn't directly absorb a lot of sunlight and melt the whole snow surface. Instead, it changes the local snow grain in which it is embedded, causing the grain to partially melt and form a larger, rounder grain when it refreezes. These larger grains absorb more energy than the fluffy snow, and they also allow sunlight to penetrate more deeply into the snowpack. It is these feedbacks of snow grain morphology that cause the bulk of the warming impact of the soot. Complicated stuff, and not very well understood. Soot is only one of many causes of snow metamorphosis. BP- Concentrations of soot in the Arctic atmosphere have declined quite a bit since the breakup of the USSR, although they seem to have leveled off and may be slightly increasing now due to Chinese emissions. Most soot in the Arctic snow seems to come from forest and agricultural burning, anyway. It is a big stretch to attribute the dramatic Arctic sea-ice decline in recent years to Chinese soot emissions--it is probably a minor player given the big changes in air and ocean temperature that have occurred in the last 40 years. It's also interesting to see you pointing to one of Hansen's GISS models to support one of your points. I presume then that you accept the general findings from that group's other climate simulations?
  35. 2nd law of thermodynamics contradicts greenhouse theory
    Fred Is the atmosphere being actively compressed by gravity? Is it more dense here at the surface than it was yesterday? The answer, of course, is no. Therefore no work is being done. Indeed, we can experience this in everyday life. Pump up your bicyle tyres quickly to 60psi. You've done work on them and they've gotten hotter due to compression. Leave the bike alone for a bit and come back later. The tyres are now at the ambient temperature. How did that happen? They're still at 60psi (the force analagous to gravity here is the tension of the inner tube) but the fact that they're at significantly higher pressure than their surroundings doesn't make them hotter*. Gravity, like the tension of an inner tube, is no substitute for thermodynamics. *PS I had one 'sceptic' argue back that when you cycle around the tires get hot. Apparently not familiar with friction!
  36. Soot and global warming
    kdkd#17: "Grab a range of different data sets ... " Here's one. What a correlation! By BP's logic, "reduced summer ice cover in the Arctic is clearly caused by ... " atmospheric CO2. Time series of annual arctic sea-ice extent and atmospheric concentrations of CO2 for 1900-2007. Sea-ice observations are from the Walsh and Chapman dataset 1900-78, merged with sea-ice concentration retrieved from satellite passive-microwave data (1979-2007) using the NORSEX algorithm, with ice extent updated to 2007. The CO2 scale is inverted. -- from The Nansen Group, Responding to Climate Change 2010
  37. Berényi Péter at 04:14 AM on 4 April 2011
    Soot and global warming
    #17 kdkd at 21:36 PM on 3 April, 2011 I'm going to go out on a limb and conclude that there's a 95% chance or greater that your causal explanation is only a very very small part of the story. While on that limb, please read the peer reviewed literature, then come down safely. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 110, D04204, 2005 doi:10.1029/2004JD005296 Distant origins of Arctic black carbon: A Goddard Institute for Space Studies ModelE experiment Dorothy Koch and James Hansen "The (former) Soviet Union (FSU) was implicated as a major source of Arctic haze in many studies. Novakov et al. [2003] found that black carbon emissions from the FSU in the late 1990s was less than 1/4 their peak levels of 1980. European emissions are also about 1/3 their levels in the 1970s. However China and India have doubled their BC emissions since the late 1970s. Thus BC emissions are more heavily weighted toward south Asia than they were in the 1970s and 1980s, when many of the Arctic haze studies took place."
  38. Philippe Chantreau at 04:04 AM on 4 April 2011
    2nd law of thermodynamics contradicts greenhouse theory
    Fred Staples, "Please don’t expect anything conclusive." Fear not.
  39. Philippe Chantreau at 03:54 AM on 4 April 2011
    2nd law of thermodynamics contradicts greenhouse theory
    LJR, your shouting is not impressive. As for this question " have confidence radiative forcing will work?" Answer is yes. Muoncounter above summarizes well some of your confusion. You should look again at Pr Jin-Yi Yu's lecture. This statement:"So if I have got it wrong so does he" does not follow from logic at all.
  40. Fred Staples at 03:45 AM on 4 April 2011
    2nd law of thermodynamics contradicts greenhouse theory
    I am sorry not to have responded before this, damorbel (872). Sadly, in the interval, we seem to have left basic thermodynamics (and G and T) behind. Heat is not what is measured by temperature. Internal energy is what is measured by temperature. Before internal energy can do anything (create work or raise temperature elsewhere) it must be transferred from a higher to a lower temperature, from a source to a sink. It will then become heat, which is the net transfer of energy, and the work it generates, or the warming it produces, will conform to the second law. That is why we must use the net transfer of energy to the atmosphere, e 873, from the surface, and not the back transfer (the negative term in Stefan Bolzmann) to calculate any possible GHG effects. From the source, surface, to the sink, atmosphere, most of the energy transfer is via conduction, convection and evaporation. From the source, atmosphere, to the final sink, space, all the transfer is radiative. However, the first and second laws are not concerned with transfer mechanisms. The final outgoing energy, atmosphere to space, must balance the incoming solar energy (first law). 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. So why is the surface temperature about 33 degrees C higher? Because of the lapse rate. As damorbel has pointed out, gravity compresses the atmosphere and the work done in the compression warms it up. This has nothing to with radiative effects. It is a function of gravity and specific heat (page 45 of Elementary Climate Physics by Taylor), and is about 6K per kilometre of altitude. So, we if we can accept: 1) that there is sufficient water vapour in the atmosphere to absorb all, or nearly all, of the net outgoing energy, and 2) the effective radiative temperature of the atmosphere to space is 255K at an effective altitude of about 5 kilometres, there is no need to pursue greenhouse theory into the realms of quantum electrodynamics. G and T are right, and the simplistic “back-radiation” theories of AGW are wrong. However, there is one more explanation that is more difficult to refute: the “higher is colder” theory which suggests that increased absorption in the atmosphere will raise the effective radiative altitude to a higher and colder level via the lapse rate. This will reduce outgoing radiation, and the atmosphere and surface will warm to compensate. Effectively, the lapse rate will shift to the right. Does the evidence support this theory? The radio-sonde and satellite data should show this effect over the past 40 years when CO2 has been increasing relatively rapidly. I will down-load the data to try to find out. Please don’t expect anything conclusive.
    Moderator Response: Not gravity again :( See, among other rebuttals, Tamino's little gem, the detailed response (be sure to read the comments, too) by Chris Colose, and the lengthier series of posts on Science of Doom. If that's not enough, start searching the intertubes for "Steven Goddard Venus."
  41. 2nd law of thermodynamics contradicts greenhouse theory
    LJR is banging the table based on his notion that 'the blackbody temp at a given flux represents the maximum temperature.' Putting this unsubstantiated phrase into the google machine, there are no occurrences of it other than in these SkS comments. There don't even appear to be any denier blogs sourcing this sentence. However, there are multiple occurrences of statements which say, in essence, 'the wavelength of maximum flux represents (in this case via an inverse proportion) the blackbody temperature.' Are we simply witnessing a case of reversed word order? If so, this is truly much ado about nothing.
  42. Arctic Ice March 2011
    Perhaps the "distracting and confusing people with gibberish" portion of the audience could take their 'argument' to the Flanner thread. And a kind reminder to those having difficulty with comprehension is that the title of this thread is: "Arctic Ice March 2011" And yes, having to perpetually deal with those who choose to dissemble and disinform is getting tiresome and annoying as it detracts from the science and the important issues at hand that should not be ignored (as some want readers to do)-- so I make no apologies for my terse and condescending tone towards those who seek to dissemble and disinform on the science.
  43. Arctic Ice March 2011
    Wow, the contrarians sure are trying hard to derail this thread and ignore the canary in the coal mine that is the dramatic loss of summer Arctic sea ice (and land ice)-- paying attention to that is in fact placing things in perspective (see quote below). The obfuscation here by contrarians and wanna-be skeptics smacks of pure desperation. As for control knobs of global temperatures--on an annual scale-- it is the mid and high latitude continents that are the a major control knob, as evidenced by the peak in global temperatures observed during the summer months that is clearly visible in the lower troposphere satellite data. It is for this reason that Dr. Meier from the NSIDC (National Snow and Ice Data Center in the USA) is on record saying that "Arctic sea ice functions like an air conditioner for the global climate system by naturally cooling air and water masses, playing a key role in ocean circulation and reflecting solar radiation back into space". Now who to take seriously? Contrarian, D-K type posters on an internet blog or the NSIDC? The NSIDC of course. Intriguing how the loss of the "air conditioner" does not concern some-- how incredibly myopic. CBDunkerson @75 is right, the Antarctic is losing ice mass, and at an accelerated rate too if I recall correctly.
  44. 2nd law of thermodynamics contradicts greenhouse theory
    - 240 W/m^2 enters the climate at TOA (boundary condition), including all SW albedo effects. The appropriate satisfaction of that boundary condition is that 240 W/m^2 leave the TOA. However, you make the (false) assumption that this power level is a boundary condition on the surface. That boundary condition misapplication is a huge error, and leads you in the wrong directions, and to ridiculous results. Surely this assumption that LJR makes is equivalent to assuming that there >is no Greenhouse effect. In other words LJR's argument is circular: he's assuming what he's trying to prove.
  45. 2nd law of thermodynamics contradicts greenhouse theory
    L.J. Ryan - The most important issues I see with your postings are: - Absorptivity/albedo vary with wavelength; your initial problem statement did not incorporate that. - 240 W/m^2 enters the climate at TOA (boundary condition), including all SW albedo effects. The appropriate satisfaction of that boundary condition is that 240 W/m^2 leave the TOA. However, you make the (false) assumption that this power level is a boundary condition on the surface. That boundary condition misapplication is a huge error, and leads you in the wrong directions, and to ridiculous results. As stated before, given a known amount of outgoing radiation, the black body temperature is an absolute minimum on the temperature of an equivalently radiating graybody, due to the relationship of emissivity and temperature. The following is a rough zero dimensional calculation, but actually is quite close to measured effects: Without GHG's (ignoring affects on SW albedo), 240 W/m^2 of SW would enter the climate, and the only exit would be LW radiation from the surface through LW transparent atmosphere, average surface LW emissivity of 0.98, hence a temperature of -16.7C. With GHG's and an effective LW emissivity of 0.612 (that's measured, L.J., not made up, from the LW spectra to low orbit), the temperature is: T = [ P / ( ε * σ ) ]^0.25 K (Stefan-Boltzmann equation) or [ 240/(0.612 * 5.6704*10^-8 ]^0.25 - 273.15 = 15.2C Which, not surprisingly, matches our experience; ~15C surface temperature. Those are the measurements and the math, with an appropriately applied boundary condition of 240 in/240 out. If your hypothesis does not match the measurements, it's probably time for a new hypothesis!
  46. Arctic Ice March 2011
    On Antarctica, keep in mind that it is undergoing significant ice mass loss >currently< despite the sub-zero air temperatures. This is because water temperatures do get above freezing and lead to breakup of ice shelves and coastal ice that sea water can undermine. Loss of that coastal ice also allows the formerly 'land locked' ice behind it to flow towards the sea much more quickly. Thus, even without a huge further increase in CO2 levels we can likely expect to see the total volume of Antarctic ice slowly decreasing until mass gain and loss come into equilibrium again... which probably wouldn't happen until all the thicker ice which formed under the previous equilibrium state has flowed out to sea and been replaced by thinner ice formed at the new accumulation rate... which would likely require thousands of years. Thus, I'd agree that we likely won't see much increase in the amount of ice-free coastline unless CO2/temperatures go up significantly, but that doesn't mean Antarctica won't be losing ice mass. The ice area may not change much, but the volume / mass will. Which is actually similar to what we have been seeing in the Arctic... decrease in ice area / extent lags significantly behind decrease in ice volume / mass.
  47. Arctic Ice March 2011
    Sorry slight typo: The polar solar radiation at TOA will therefore irradiate 2.5 sq.m of area at 23.4 degrees angle of incidence.............
  48. Arctic Ice March 2011
    Sphaerica #69 "Stop distracting and confusing people with gibberish". When I went to school the Earth's axis was tilted at about 23.4 degrees to the plane of orbit around the sun. This means that at the poles, the sun's angle of incidence is +23.4 degrees in the summer and -23.4 degrees in the winter (it is in the shade). The Arctic was famously called the land of the midnight sun in the middle of the northern summer because on the Arctic circle at noon the angle of incidence was a maximum of 46.8 (2 x 23.4) degrees and at midnight it was 0 degrees but still light because the 23.4 degree tilt of the Earth kept the latitude of 66.6 degrees north just tangential to the sun. The Earth still rotates once every 24 hours (even in the Arctic summer cooker), and therefore in a 24 hour period the whole of the 4.4% of the Arctic surface above 66.6N is subjected to a varying angle of incidence between 46.8 degrees and 0. Average 23.4 degrees. The Sine of 23.4 degrees is 0.4 which means that the inverse is about 2.5. The polar solar radiation at TOA will therefore irradiate 2.4 sq.m of area at 23.4 degrees angle of incidence, compared with 1.09 sq.m at the Equator and 1.00 sq.m at the Tropic of Cancer at the northern summer solstice. Further, the solar energy has to travel commensurately further through the Earth's atmosphere at these low incidence angles and is subject to more scatter. To quote you: "Since at that time of year the angle of incidence is great than that at the tropics (66˚ at peak), it is like a non-stop tropical sun." The Arctic summer peak at the pole, dear Sphaerica, is not 66 degrees angle of incidence, but 23.4 degrees. So what was this about my talking gibberish?
  49. The Climate Show Episode 10: David Suzuki and the sun
    What is the scientific explanation as to why the divergence happens after the 70s and not early in the 20th century?
    Response: Dana wrote a good overview of what drove early 20th Century climate.
  50. Eric (skeptic) at 00:24 AM on 4 April 2011
    It's cooling
    michael sweet, the other reason more harp seals show up farther away is that there are more of them. See figure 7 here: http://www.dfo-mpo.gc.ca/fm-gp/seal-phoque/seal_harp_%202009-eng.pdf Their biggest problem by far is hunting, not ice.

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