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From: bill.sloman on 28 Nov 2008 22:35 On 28 nov, 14:20, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > z wrote: > > and the fact that water vapor partial pressure rises with temperature, > > thereby making it an amplifier of other effects, such as CO2. > > An unproven hypothesis. i.e random noise. There's nothing unproven about the "hypothesis" that the partial pressure of water vapour in contact with liquid water rises with temperature. It's up there with Newton's law of gravity as one of the fundamental theories of science. And more water vapour does mean more pressure broadening in the carbon dioxide absorbtion spectrum. Carbonic acid (H2CO3) may not be stable in the vapour phase at room temperature, but it is stable enough that any collision between a water molecule and a carbon dioxide molecule lasts qute a bit longer than you'd calculate from a billiard-ball model. Eeyore's response isn't random noise either, though it's information content isn't any more useful - we already knew that Eeyore knows squat about physics, and he's long since made it clear than he doesn't realise how little he knows by posting loads of these over-confident and thoroughly absurd assertions. -- Bill Sloman, Nijmegen
From: bill.sloman on 28 Nov 2008 23:05 On 28 nov, 21:16, Whata Fool <wh...(a)fool.ami> wrote: > bill.slo...(a)ieee.org wrote: > >On 28 nov, 04:27, Whata Fool <wh...(a)fool.ami> wrote: > >> Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > > >> >Whata Fool wrote: > > >> >> bill.slo...(a)ieee.org wrote: > > >> >> >The oxygen and nitrogen molecules exchange energy with carbon dioxide > >> >> >molecules whenever they collide, so the carbon dioxide radiates for > >> >> >them. > > >> >> Ignoring water vapor again? Is that a mental problem, or > >> >> an order from control? > > >> >LMFAO ! > > >> >I though it was an acknowledged fact that water vapour is the big factor in climate. > > >> >Graham > > >> I should not have been flippant, the last couple of replies seem > >> to suggest that the atmosphere would get hotter without any GHGs, and > >> you know what that means to GreenHouse Theory and Anthropogenic Global > >> Warming. > > >That suggestion is generated by your own inadequate understanding of > >the subject under discussion. You clearly don't know enough elementary > >physics to undertand what I'm telling you, and this forum isn't a > >suitable place for me to take you through a beginner's course in the > >subject. > > Why, do you usually teach kindergarten? No. As a graduate student and a post-doc I did do some low-level undergraduate teaching, which seemed to work tolerably well. I do better with graduate students and junior engineers. I've also had to instruct my bosses from time to time, which they didn't always enjoy. I find it difficult to suffer fools gladly, and the late Tony Williams would congratulate me whenever I succeeded in suggesting that someone had got something wrong without implying that they were a little stupid. You've been rude and wrong often enough that I'm not going to spend time extending this sort of consideration to you. -- Bill Sloman, Nijmegen
From: bill.sloman on 28 Nov 2008 23:10 On 28 nov, 23:24, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: > On Fri, 28 Nov 2008 15:16:14 -0500, Whata Fool wrote: > > bill.slo...(a)ieee.org wrote: > > >>On 28 nov, 04:27, Whata Fool <wh...(a)fool.ami> wrote: > >>> Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > > >>> >Whata Fool wrote: > > >>> >> bill.slo...(a)ieee.org wrote: > > >>> >> >The oxygen and nitrogen molecules exchange energy with carbon > >>> >> >dioxide molecules whenever they collide, so the carbon dioxide > >>> >> >radiates for them. > > >>> >> Ignoring water vapor again? Is that a mental > >>> >> problem, or an order from control? > > >>> >LMFAO ! > > >>> >I though it was an acknowledged fact that water vapour is the big > >>> >factor in climate. > > >>> >Graham > > >>> I should not have been flippant, the last couple of replies > >>> seem to suggest that the atmosphere would get hotter without any GHGs, > >>> and you know what that means to GreenHouse Theory and Anthropogenic > >>> Global Warming. > > >>That suggestion is generated by your own inadequate understanding of the > >>subject under discussion. You clearly don't know enough elementary > >>physics to undertand what I'm telling you, and this forum isn't a > >>suitalbe place for me to take you through a beginner's course in the > >>subject. > > > Why, do you usually teach kindergarten? > > He wouldn't last 10 minutes. Kids that age always ask "Why?". It > usually takes until 6th or 7th grade to brainwash that curiosity out of > them. Then he might do OK. I did and do okay with my nieces and nephews. My grandnieces and grandnephews don't yet know me well enough to use me as a databank. My own parents primed me pretty well as a kid, so I don't usually have to work too hard to find an answer to the usual "why" questions. -- Bill Sloman, Nijmegen
From: bill.sloman on 28 Nov 2008 23:16 On 28 nov, 21:14, Whata Fool <wh...(a)fool.ami> wrote: > bill.slo...(a)ieee.org wrote: > >On 28 nov, 03:53, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> > >wrote: > >> Whata Fool wrote: > >> > bill.slo...(a)ieee.org wrote: > > >> > >The oxygen and nitrogen molecules exchange energy with carbon dioxide > >> > >molecules whenever they collide, so the carbon dioxide radiates for > >> > >them. > > >> > Ignoring water vapor again? Is that a mental problem, or > >> > an order from control? > > >> LMFAO ! > > >> I though it was an acknowledged fact that water vapour is the big factor in climate. > > >Whata Fool doesn't seem to appreciate that there isn't much water > >vapour in the stratosphere - at -55C the vapour pressure of water is > >low enough that it's a waste of time to include it in the model. > > >He doesn't seem to know much more science than you do. > > Radiation at -55 C and barometric pressure of .5 PSI may > not mean much, and the water vapor in the troposphere can easily > absorb any small amount of radiation headed downward from the > stratosphere and send half of it upward. > > Since you seem to concede that the N2 and O2 would be hotter > without GHGs, doesn't that mean GHGs cool the whole atmosphere? This is the kind of proposition that Dirc used to dismiss as "not even wrong". > The mass of the N2 and O2 is huge, and it takes time to cool > it after convection from the ground warms it. > > So much for "greenhouse theory So much for Whata Fool's grasp of "greenhouse" theory. He trying to run before he can creep. -- Bill Sloman, Nijmegen
From: Bill Ward on 29 Nov 2008 00:43
On Fri, 28 Nov 2008 19:25:22 -0800, bill.sloman wrote: > On 27 nov, 20:50, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> On Thu, 27 Nov 2008 07:50:47 -0800, bill.sloman wrote: >> > On 27 nov, 06:32, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> >> On Wed, 26 Nov 2008 17:09:40 -0800, bill.sloman wrote: >> >> > On 26 nov, 22:17, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> >> >> On Wed, 26 Nov 2008 07:53:11 -0800, bill.sloman wrote: >> >> >> > On 26 nov, 12:28, Whata Fool <wh...(a)fool.ami> wrote: >> >> >> >> Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: >> >> >> >> >> >bill.slo...(a)ieee.org wrote: >> >> > <snip> >> >> >> As you put it up thread, "the stratosphere isn't functioning as an >> >> insulator." >> >> >> If the stratosphere is transparent, and there is an excess of >> >> convective capacity in the troposphere (driven by the lapse rate), >> >> how can trace amounts of CO2 affect surface temperatures? If >> >> convection is sufficient to get latent heat to the tropopause, where >> >> it can radiate from cloud tops, etc, it has a clear shot at 3K deep >> >> space. The tropopause is there because it represents the top of the >> >> convective mixing layer. Because of increasing UV heating, the >> >> stratosphere has an inverted lapse rate, which prevents convection. >> >> > You seem to have set up a straw man by claiming that you can slice the >> > atmosphere into three layers - >> >> > - the troposphere where heat transfer is only by convection >> >> > - a very thin tropopause which does all the radiation >> >> > - the stratosphere which does nothing >> >> > which - unsurprisingly - leads you to incorrectly conclude that CO2 >> > cann't do anything. >> >> Where did I say the radiation all comes from a thin layer? You must be >> misinterpreting the concept of effective radiating altitude. > > I very much doubt it. The proposition that the you think that all the > radiation comes from a thin layar at the tropopause folows direcly from > your claim that radiation doesn't play a significant role anywhere in the > troposphere, which strikes me as implausible. Below the effective radiating layer (cloud tops) radiation is swamped by convection, so CO2 can have little effect. Above the radiating layer, there's not much CO2 left, and the 15u band is off peak, so it can have little effect. In the radiating layer, CO2 is radiating to space like everything else. Why do you think the radiating layer must be thin? I said "layer", not "surface". > >> >> >> IR radiated from the surface would be quickly absorbed by WV, >> >> >> clouds, CO2, and other GHGs, and at 500W/m^2 would be overwhelmed >> >> >> by the 10's of kW/m^2 available from convection of latent heat. >> >> >> > Clouds scatter infra-red radiation rather than absorbing it. as do >> >> > the greenhouse gases, but that's enough to sustain a thermal >> >> > gradient. >> >> >> Surely you're not proposing the lapse rate is sustained by outgoing >> >> IR. All the sources I've seen say the troposphere is due to >> >> convection, not radiation. Can you find one to the contrary. >> >> > Don't have to. Convection and transport as latent heat both decrease >> > rapidly as you move up through the troposphere, and radiation >> > progressively takes over, becoming responsible for 100% of the heat >> > transfer by the time you get to the tropopause. This is clearly >> > implied by what I wrote earlier (which is why I've not snipped it). >> >> So you don't really understand convection or radiation. If you did, >> you might see that radiation could not generate a "thermal gradient". >> Radiation tends to equalize temperatures, you know. > > Only when it is reabsorbed. Radiation from the flanks of pressure- > broadened rotational lines isn't going to be reabsorbed higher up where > the pressure broadening is less, and radiation from water vapour isn't > going to be absorbed once you get up to height where almost all the waer > vapour has frozen out - which seems to be about half way through the > troposphere, if I've correctly interpreted the significance of the > effective radiating altitude (which is an average over all wavelengths). So you really think the lapse rate is set by radiation? And it just happens to be near adiabatic? Fascinating. Somehow I'm reminded of the adage,"When all you have is a hammer, everything looks like a nail." http://en.wikipedia.org/wiki/Troposphere "The word troposphere derives from the Greek "tropos" for "turning" or "mixing," reflecting the fact that turbulent mixing plays an important role in the troposphere's structure and behavior." You think IR is doing the mixing? Only when it's converted to sensible heat. >> It's described by all that second law stuff you must have somehow >> skipped over. > > If only I could have skipped over it. I had to slog my way through a lot > of work to get my head around that concept back in 1961, but my > subsequent encounters with the subject do suggest that my teachers > managed to get me onto the right track. Just keep in mind you can't actually heat a hot source from a cold target. All you can do is slow the rate of cooling of the hot source. The sky is cold, the surface is hot. >> The lapse rate is set by gas laws. Convection occurs because warm air >> is less dense than cold air, so it rises, expands, and adiabatically >> cools, still maintaining a higher temperature than its surroundings. It >> continues up until it reaches an altitude where the air around it is >> slightly warmer (the lapse rate changes) than its adiabatic >> temperature, where it releases its excess energy and stops, moving the >> lapse rate toward adiabatic. >> >> If the air rises to its dewpoint temperature, WV condenses, releasing >> latent heat and giving the rising parcel a boost. Go out and watch a >> cumulus cloud and you can see the flat bottom at the condensation >> altitude, and the energetic billowing of the cloud upward from the >> latent heat release. The principle is scalable, that's why >> thunderstorms can billow up well into the stratosphere, yielding the >> "anvil" shape. > > Thunderheads are rare. Normally all the water vapour (and the latent > heat) has condensed out at around 6km, and that - large - proportion of > the greenhouse effect that depends on absorption by lines in the water > vapour spectrum goes away, and - for those wavelengths - this opens the > window to outer space. Check out a satellite view of the tropics. Deep convection is pretty common. > >> >> > Convection becomes progressively less potent as air pressure and >> >> > thus density declines with height, and as the partial pressure of >> >> > water vapour declines with decreasing temperature as it climbs up >> >> > through the tropopause, so the amount of energy transferred as >> >> > latent heat falls away with height in the same sort of way. >> >> See above, then consider what happens when an airplane encounters a TS >> at 20000 feet. IR doesn't disassemble aircraft in flight. There's >> plenty of energy in convection, even at altitude. > > Thunderstorms don't occupy a particulary significant proportion of the > sky. If you want to calculate the additional global warming you get from > a few more parts per million of CO2, you don't need to allocate all that > many cells to air columns that look like thunderheads. The point is that convection remains active, including destructive turbulence, well into the stratosphere. The amount of energy cannot decrease with increasing altitude. There's no way down. You can't transfer net energy from cold high altitudes to the hot surface. > >> > <snip> >> >> Now why did you try to hide what I was responding to? You should know >> that won't work. >> >> <unsnip> > > Because it wasn't information that I saw any need to reiterate. You snipped the part I responded to, where you agreed with me about solar energy powering convection. > >> >> At night, convection stops, but cooling is not required at night. >> >> Convection kicks in during the day, when cooling is needed. >> >> >> I don't see how radiative cooling is even necessary below the cloud >> >> tops, since there's plenty of cooling capacity from convection. >> >> > And there's solar energy availalbe to fuel it. >> >> <end unsnip> >> >> >> Exactly. It's a heat engine, with water as the working fluid. It >> >> cools the surface by using solar energy to convect latent heat to >> >> the cloud tops, from which it radiates as a black body to deep >> >> space. Cloud shadows are a strong, easily observable negative >> >> temperature feedback, since they cut off surface heating as the >> >> clouds develop. >> >> >> >> Once the energy reaches the tropopause, as you imply, it's a >> >> >> pretty straight shot to 3K deep space, since there's not much >> >> >> atmosphere left to absorb IR. >> >> > 25% of the mass of the atmosphere lies above the tropopause, and 25% >> > of the CO2. There's very little water vapour in the stratosphere - at >> > -55C any water around is ice. >> >> You need to keep your stories straight: >> >> Up thread, on: Wed, 26 Nov 2008 07:53:11 -0800 (PST) >> >> You said: >> "Sure. Most of the mass of the atmosphere - about 90% - is below the >> tropopause. But the stratosphere stretches out quite a long way." > > Ouch. I should have made sure that I was using the same sources on both > occasions. > >> Do you always adjust the facts to match your argument? > > Certainly not. This is a mistake. I don't yet know precisely what kind > of mistake it is. I do know that I don't post that kind of figure > without finding a source for it, but I'm by no means confident that I'll > be able to find the conflicting sources and reconcile them > >> How do you expect to retain any credibility? > > Easily. We all make mistakes from time to time, and when someone catches > me out, I thank them and apologise. I don't like having to do it, and > don't have to do it often. > >> >> >> Perhaps it's easier to see if you look at the lapse rate as >> >> >> bounded at the top by the effective radiating temperature, and >> >> >> consider the surface temperatures as derived from that and the >> >> >> adiabatic lapse rate. >> >> >> > This approach doesn't make it easy to see how increasing levels of >> >> > greenhouse gases produce more greenhouse warming. >> >> >> Correct. Now show me how greenhouse warming is supposed to work, in >> >> view of the inconsistencies I've pointed out. >> >> > This was a pedagogic point. I didn't intend to suggest that CO2 >> > wasn't an effective greenhouse gas, merely that this wasn't a way of >> > looking at what was going on that was helpful in letting you see >> > where the greenhouse effect is going on. >> >> So where is your explanation of how greenhouse warming is supposed to >> work, in view of the inconsistencies I've pointed out? >> >> >> CO2 isn't effective in the troposphere, because radiation is swamped >> >> by the convective transfer required to maintain the lapse rate. CO2 >> >> isn't effective in the stratosphere, partly because there's so >> >> little left, and partly because it would actually cool by radiating >> >> IR at the higher stratospheric temperatures. >> >> >> So where is the CO2 causing global warming? >> >> > CO2 is not effective at the bottom of the troposphere, but it becomes >> > progressively more effective as you climb up through the troposphere >> > towards the tropopause. >> > and presumably exerts most of its effect in the upper layers of the >> > troposphere, where - incidentally - there isn't much water vapour >> > left, since it freezes out as the air gets higher and colder. >> >> >> > Convective heat >> >> > transfer normally stops at the tropopause - though energetic >> >> > thunder- heads can go higher for a while - and slows down a lot >> >> > before it gets to the tropopause, so presumably the greenhouse >> >> > effect is mainly active in the upper layers of the troposphere. >> >> >> Which is above most of the atmosphere, and dry, so the postulated >> >> positive feedback from WV also looks highly unlikely. >> >> > Only if you persist in thinking that everything has to happen in an >> > infinitely thin layer, which isn't a realistic model (which might not >> > matter if it gave the right sort of answer, which it doesn't), nor - >> > more important - a useful model, >> >> First, the thin layer bit is yours - I never even implied it. > > Actually you did - by denying any role for radiation below the > tropopause, which is clearly absurd. > >> Second, apparently you think a model is only useful if it, "(gives) the >> right sort of answer". Yet you continue to prattle on about radiative >> transfer models even though you admit they would only be useful in a >> limited region at the top of the troposphere. > > Since the effective radiating altitude is 6km above ground, right in the > middle of the troposphere, this seems to be exactly the right place for > a radiative transfer model to be effective. There's an excess of water vapor available to convect latent heat up to the effective radiating altitude. It's in the 10s of kW/m^2 compared to the 500W/m^2 max from surface radiation. The lower troposphere is translucent in the 15u band. How could CO2 play any significant part, compared to radiation? Above the clouds, it has a clear shot to space. > > In fact it looks to me as if we need to regard the effective radiating > altitude as wavelength dependent. This altitude (when averaged over all > wavelengths) seems to coincide with the 6km where you'd expect water > vapour to stop being an an effective greenhouse gas (because it is > frozen out at higher altitudes). For the limited number of wavelengths > where carbon dioxide absorbs the effective radiating altitude seems > likely to be up in the stratosphere, where the air is a lot colder > (below the very low density outer bit which gets heated by charged > particles from the sun). And where the CO2 has a cooling effect. The stratosphere has an inverted lapse rate. > > Additional carbon dioxide in the atmosphere could then be seen as > increasing the greenhouse effect primarily by increasing the pressure > broadening of the water absorbtion lines - blocking a greater proportion > of the infra-red radiation from the ground and moving the effective > radiating altitude for water vapour absorbtion lines a bit further up > into the troposphere where the air is even cooler. The effective > radiating altitude for the radiation that is absorbed by carbon dioxide > might change if you've got more carbon dioxide around, but since it's > still going to be in the stratosphere and there isn't much of a > temperature gradient in the bulk of the stratosphere this won't > significantly alter this component of the greenhouse effect. > >> >> I'm slightly encouraged by your post. Did I misinterpret any of the >> >> points where you appear to agree with me? >> >> > Obviously. >> >> Well, optimism loses again. > > You may like to think so, but I don't think your arguments are good > enough to carry your case. I'm not sure if if this post is out of sequence. It seems to be. |