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Comments 376 to 400 out of 421:

376. KR at 07:00 AM on 28 December, 2010
     co2isnotevil - Your post here has far more incorrect statements than correct ones (if any). The Earth is not a black-body radiator, but a 'gray-body', as seen in the TOA spectra (Figure 1 here). The 'gain' is a variant result, not an input, and doesn't actually relate to the visible light input power and thermal IR output power physics. "is that it takes 16 W/m^2 of incremental surface power for a 3C rise in surface temperature" is absolutely incorrect. 3.Y W/m^2 at TOA accounts for a 1.2C CO2 forcing, and feedbacks are expected to raise that to 3C. A raw forcing of 3C from CO2 would require 9.25 W/m^2, and from that we would expect 7.5C of rise with feedback. Your 'amplification factor' is nonsense. http://www.palisad.com/co2 consists of exceedingly bad numbers (as I noted here), misinformation, and a collection of denier themes that can be found searching the top 20 skeptic arguments here. That's not a good source, but rather a quick trip into irrelevancy. I could go on, but I quite frankly don't see any point in it.
377. RW1 at 07:23 AM on 28 December, 2010
     KR, "The Earth is not a black-body radiator, but a 'gray-body'" But the surface of the earth is very close to a perfect black body radiator. This is why S-B (where emissivity "e" = 1) is used to calculate equivalent surface power to temperature and vice versa. "is that it takes 16 W/m^2 of incremental surface power for a 3C rise in surface temperature" is absolutely incorrect. 3.Y W/m^2 at TOA accounts for a 1.2C CO2 forcing, and feedbacks are expected to raise that to 3C. A raw forcing of 3C from CO2 would require 9.25 W/m^2, and from that we would expect 7.5C of rise with feedback. Your 'amplification factor' is nonsense." From S-B, at a surface power of 396, it takes 16 W/m^2 of additional power to increase the surface temperature 3 C. (396 + 16 = 412 W/m^2; 412 W/m^2 = 292K; 292K-288K = 3C).
378. Eric (skeptic) at 07:24 AM on 28 December, 2010
     co2isnotevil, in your first paragraph in 374, the Pc calculation doesn't matter, nor does Pe. As I pointed out in 208, that tangent is dropped and "gain" is determined solely from Ps. That's one of my lessons learned, don't follow tangents and don't start them. In this case I was following a tangent in the paper. As for "gain" itself, that has more than adequately been addressed above such as in 210.
379. KR at 07:26 AM on 28 December, 2010
     Mea culpa - I believe I have misinterpreted a couple of things in the last post. A 3C warming (total, from whatever source) of the surface will result in 16.8 W/m^2 increase (14C to 17C) in surface IR. At dynamic equilibrium this means an additional 16.8 W/m^2 of backradiation, +/- depending on what's changed in terms of thermal and evaporation pathways. The emissive levels in the troposphere would likely be higher, too, lots of other changes. We would still expect a power flow of ~240 W/m^2 from the sun and ~240 W/m^2 out to space as IR - the surface temperature will be driven by the input energy and total emissivity required to radiate that energy. A single 'gain' factor doesn't encompass the details of that. However - The 3.7 W/m^2 forcing from doubling CO2 will result in a direct forcing of only 1.2C. The value of 3C surface warming includes current estimates for climate sensitivity (look, actual relevance to the thread!). Hence arguing that 3.7 W/m^2 of direct forcing can't cause 16 W/m^2 of direct + feedback is mixing apples and oranges, and is a bad argument. We know what the direct forcing for a CO2 doubling will be. The climate sensitivity is rather more debatable, but appears to be ~3C for that doubling. And that means ~3C for 1.2C of solar forcing, if the insolation changes that much. Argue the forcing, or argue the sensitivity. Claiming the sensitivity issue(s) invalidate the forcing is really pointless.
380. co2isnotevil at 07:28 AM on 28 December, 2010
     KR, The difference between a BB and a grey body is well known and included in any radiative analysis. Inferring that I don't understand this tells me that you aren't paying attention. The fact that you're missing is that the surface is almost an ideal BB radiator, especially in the LW IR. The Earth itself, as seen from space, is a grey body because the atmosphere is between the surface and space. Perhaps it would also help if you understood that the theoretical maximum blocking of surface power by the atmosphere is 50%. You can test this yourself by comparing the power radiated by the coldest cloud tops and the power radiated by the surface beneath them. This will never be less than 1/2. Venus is somewhat different because the thermal mass of the planet is primarily energized CO2 above the surface, while on Earth, it's ground state water below the surface. You also don't seem to understand the Stefan-Boltzmann Law. If the surface temperature increases by from 287K to 300K (a 3C rise), it's emitted power must increase by 16 W/m^2. Conservation of energy tells us that this power flux must be coming from somewhere. There is about 3.8 W/m^2 of incremental absorption by doubling CO2 (run modtran yourself if you don't believe me). Only half of this affects the surface, so I ask you, in order to satisfy COE, where is the extra 14.2 W/m^2 coming from? If you think it's the feedback, then I suggest you go back and study Bode and basic thermodynamics.
381. KR at 07:36 AM on 28 December, 2010
     RW1 - The surface of the Earth is close to being a decent black-body, with an emissivity of 0.96 to 0.99. However, the effective emissivity with cloud cover and GHG's is 0.612. The temperature (at dynamic equilibrium) of the surface of the Earth is determined by input energy from the sun to the surface and atmosphere and the effective emissivity of the Earth, which notably changes due to GHG concentration. Without GHG's it would be at least 33C colder, for example. Again, as stated here: don't talk about 3C warming from a 3.7 W/m^2 CO2 forcing unless you include the feedback that raises 1.2C forcing to 3C temperature change. That's the climate sensitivity, which (primarily through water vapor effects) is expected to multiply the forcing by ~2.5. You seem to keep mixing the total forcing+feedback to try to argue against the forcing.
382. Eric (skeptic) at 07:38 AM on 28 December, 2010
     co2isnotevil, a question for you. Do you, like RW1, believe that the 396 W/m^2 shown in http://www.palisad.com/co2/div2/div2.html includes latent heat transfer and thermals? If so, show any scientific source that confirms that SB includes nonradiative transfer. If not, please correct RW1's misconception and then explain why latent heat and thermal transfer to the atmosphere can be ignored (along with solar heating of the atmosphere)
383. KR at 07:40 AM on 28 December, 2010
     co2isnotevil: "There is about 3.8 W/m^2 of incremental absorption by doubling CO2 ... Only half of this affects the surface" Absolutely, completely... incorrect. This has been repeatedly pointed out since comment #7.
384. co2isnotevil at 07:42 AM on 28 December, 2010
     KR, The 3.8 W/m^ of incremental absorption will have only a direct effect on the surface of 1.9 W/m^2, corresponding to only about 0.4C. The surface gain multiplies this by 1.6 for a total of 3 W/m^2 which presents a post feedback rise of 0.6C, which is consistent with values presented by Lindzen, Spencer and others who have arrived at similar values by orthogonal means. Actually, doubling CO2 increases the 1.6 surface gain by about 1%, but for all intents and purposes this can be considered negligible. This is the fundamental problem. What you think of as feedback is really gain. This is a result of Hansen et all (1984) assuming unit open loop gain and which has since permeated all of pedantic climate science. The consequence is that positive feedback is required to achieve the measured surface gain and because few climate scientists, if any, actually understand control theory, the idea of positive feedback makes it scary.
385. RW1 at 07:47 AM on 28 December, 2010
     KR, "RW1 - The surface of the Earth is close to being a decent black-body, with an emissivity of 0.96 to 0.99. However, the effective emissivity with cloud cover and GHG's is 0.612." Those numbers are for the whole atmosphere - not the surface. At a temperature of 289K where "e" = 0.612, the calculated power is 242 W/m^2, which is pretty close to 255K temperature as seen from space.
386. KR at 07:57 AM on 28 December, 2010
     co2isnotevil - A 3.7 W/m^2 imbalance caused by doubling CO2 (not halved, mind you, that's nonsense) will require a 1.2C rise in temperature in order for the Earth/atmosphere to radiate the extra 3.7 W/m^2 to space. That's a 6.6 W/m*2 increase in surface IR, a 6.6 W/m^2 (+/- depending again on evaporation and thermal effects) increase in surface air IR and temperature. A 3C rise will occur only due to climate sensitivity, primarily additional water vapor. Arguing against the 3.7 W/m^2 CO2 doubling forcing based on climate sensitivity, while avoiding mentioning climate sensitivity as you have, is a ridiculous argument. RW1 - Exactly right. The effective emissivity drives the temperature in the absence of solar variations. Solar variations are discussed on It's the sun - those do not correlate with recent temperature changes.
387. co2isnotevil at 07:59 AM on 28 December, 2010
     Eric, The 396 Wm^2 actually comes from Trentbert's picture and corresponds to the surface radiation at an average temperature of 289K. The satellite measured average temperature is only about 287K corresponding to about 385 W/m^2 shown in div2.html. In neither case does it include thermals and latent heat. As I pointed out earlier, evaporation and weather as well as thermals comprise circulation currents which move energy around the Earth's thermal mass, between the oceans and clouds (evaporation) and within the atmosphere (thermals). Consider that hot air rising from a thermal is replaced with cold air beneath creating a vertical circulation current. What goes up must come down and what Trentbert does is lump in the energy returned to the surface as weather and originating from the latent heat of evaporation as 'back radiation' as well as the return flux from thermals. This is highly misleading and why so many are so confused. The simple fact is that relative to the radiative balance of the planet, only radiation matters. Is there any question that at the boundary of the Earth and space only EM energy arrives and leaves? Can you describe the physical mechanism for how a thermal will influence the radiative balance? If you really think evaporation/weather matters to the balance, then why don't you consider other oceanic and atmospheric circulation currents?
388. e at 08:01 AM on 28 December, 2010
     co2isnotevil> The surface gain multiplies this by 1.6 for a total of 3 W/m^2 which presents a post feedback rise of 0.6C You're not listening to what KR is telling you. Your gain value does include any climate feedbacks, it is just a quantification of the strength of the greenhouse effect for a particular time period. The feedbacks are themselves an increase in the greenhouse effect on top of the original CO2 increase, which acts to increase the gain in addition to the direct increase from CO2.
389. KR at 08:03 AM on 28 December, 2010
     co2isnotevil - "Can you describe the physical mechanism for how a thermal will influence the radiative balance?" Yes. See the posting here.
390. co2isnotevil at 08:06 AM on 28 December, 2010
     KR, You are incorrect because the IPCC incorrectly defines incremental absorption at the top of the troposphere as the forcing. This is because they fail to acknowledge that the atmosphere itself is a BB (actually gray) and radiates absorbed power away both up and down. Only half of the incremental absorption arrives at the surface to influence its temperature. You must get past the false authority of the IPCC before you will ever be able to understand how the climate operates. Are you trying to say that a heated gas will not radiate BB radiation? Are you trying to say that when the atmosphere absorbs power, it never leaves? Are you trying to say that all of the BB radiation of the atmosphere is directed to the surface and none into space? Which of these falsities reflects your logic?
391. co2isnotevil at 08:15 AM on 28 December, 2010
     e, You said the gain does include feedback and that is certainly correct, but you seem to have implied that it does not. The surface gain of 1.6 is a 25 year average extracted from satellite data with nearly 100% surface coverage at 3 hour samples over that period. This certainly includes the effects of any feedback that operates on time scales of decades or less. Even the albedo effect of glacial ice is included as the gain is the average of summer and winter where the ebb and flow of the seasonal snowpack emulates the transitions between glacial and interglacial epochs. In fact, it's the increased reflectivity of the N hemisphere in winter that results in lower temperatures, even though perihelion is in Jan and temperatures should be higher. The S hemisphere operates differently because most of the surface where snow falls is water, where the snow immediately melts and can't accumulate to reflect solar power. Understanding this asymmetry is crucial to understanding how the precession of perihelion affects the climate.
392. co2isnotevil at 08:16 AM on 28 December, 2010
     KR, re 389 I refer to to post 387 which disputes your point.
393. KR at 08:17 AM on 28 December, 2010
     co2isnotevil - The forcing at the top of the atmosphere is the difference between what arrives and what leaves TOA, regardless of internal (atmospheric and surface) energy exchanges. In a single layer atmosphere (which is not the case in the actual climate) redressing that requires that the atmosphere radiate an extra ~7.4 W/m^2. Halving that means that 3.7 goes to space (correcting the imbalance at TOA), 3.7 goes to the ground. Claiming that a 3.7 TOA imbalance is halved at the surface is therefore an incorrect interpretation of the terms. Please read the thread to see the repeated corrections of this misapprehension. Given the atmospheric lapse rates, the near-total IR absorption/emission (over only a few meters) near the ground, and the fact that GHG's can only radiate to space from the colder upper troposphere, the surface IR exchanged in order to radiate 3.7 W/m^2 extra corresponds to a 1.2C surface temperature rise; about a 6.6 W/m^2 increase in surface IR and (+/-) in back-radiation.
394. Eric (skeptic) at 08:18 AM on 28 December, 2010
     co2isnotevil, the thermal quantity in Trenberth's diagram refers to the amount of heat conducted from the surface into the atmosphere. The cold air return loop that you describe as only atmospheric is considered because it determines the amount of heat conducted from the surface (determined by the temperature difference of the surface and atmosphere). Ok, now address latest heat transfer. Does evaporation, convection and condensation transfer heat from the surface to the atmosphere? Why isn't that shown in the div2 diagram? You say that latent heat transfer is one of the "circulation currents which move energy around the Earth's thermal mass, between the oceans and clouds (evaporation)" Basically you are admitting that heat is moved from the surface to the atmosphere, why isn't it in the div2 diagram? You ask "Can you describe the physical mechanism for how a thermal will influence the radiative balance? If you really think evaporation/weather matters to the balance, then why don't you consider other oceanic and atmospheric circulation currents? " Answer to Q1 is that as conduction transfers heat from the surface to the atmosphere, the temperature of the atmosphere increases and thus the back radiation. Answer to Q2 is that atmosphere to atmosphere and ocean to ocean transfer is not part of the div2 diagram only surface to atmosphere.
395. RW1 at 08:21 AM on 28 December, 2010
     Eric, "Do you, like RW1, believe that the 396 W/m^2 shown in http://www.palisad.com/co2/div2/div2.html includes latent heat transfer and thermals?" I think I was referring to "A" which is 292 W/m^2 - the total power absorbed by the atmosphere. The effects of thermals and latent heat are automatically embodied in "A". In regards to the 396 W/m^2 surface power in the Trenberth diagram, I believe you were claiming that the effects of thermals and latent heat were not included in the 396 number and somehow needed to be added in to get the correct surface power or temperature.
396. KR at 08:22 AM on 28 December, 2010
     co2isnotevil - Thermals go up, lose energy, cooler air goes down. Latent heat evaporates water, which rises, cools, and returns as precipitation. The upper atmosphere radiates energy to space (as well as to slightly lower in the atmosphere), the energy to space is lost, balancing incoming solar energy. Your post here doesn't disprove convective and thermal effects on total radiation balance, as those effects drive energy to the upper atmosphere where it then radiates to space. All of the notches in Figure 1, outgoing radiation, are IR from upper atmosphere, which receives energy from thermals and latent heat as well as IR.
397. KR at 08:25 AM on 28 December, 2010
     RW1 - "I believe you were claiming that the effects of thermals and latent heat were not included in the 396 number and somehow needed to be added in to get the correct surface power or temperature" - not quite right, in some critical points. The surface temperature of the Earth radiates 396. Thermals transport 17 at that temperature, latent heat 80. That matches the 161 direct sunlight and 333 back-radiation from the atmosphere (within 1 W/m^2), energy in = energy out. If these two sums do not match, net energy will flow, the energy of the Earth's surface will change, and so will the temperature.
398. e at 08:28 AM on 28 December, 2010
     co2isnotevil>The surface gain of 1.6 is a 25 year average extracted from satellite data with nearly 100% surface coverage at 3 hour samples over that period. If you are averaging the value over 25 years, then by definition you are hiding the increase over time caused by CO2 and any feedback effects. In order to quantify the strength of a changing greenhouse effect, you would have to express this gain as a delta over time, not a static average.
399. Eric (skeptic) at 08:29 AM on 28 December, 2010
     co2isnotevil you said "The simple fact is that relative to the radiative balance of the planet, only radiation matters" Do you, like RW1 believe that "A" in the div2 diagram accounts for thermals and latent heat transfer or is "A" simply the fraction of 385 being absorbed as shown? If the former, please explain why the thermals and latent transfer are not in the diagram. If the latter, please correct RW1 who said in #370 that "The 396 W/m^2 power flux at the surface already accounts for the thermals and latent heat transfer" and seems to now be backtracking. Please correct him so we can move on.
400. KR at 08:40 AM on 28 December, 2010
     Aha! I have found that "co2isnotevil" is actually George White (look for 'co2isnotevil'), creator of the http://www.palisad.com/co2 website referred to by RW1. Mr. White, please note my comments about your website in this post, also note that your slide presentation appears to be list of the top 20 skeptic arguments debunked here. My apologies, but I cannot take your comments seriously when you have such misinformation on your web site.

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