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From: Whata Fool on 8 Dec 2008 15:12 bill.sloman(a)ieee.org wrote: >On 8 dec, 03:02, Whata Fool <wh...(a)fool.ami> wrote: >> Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> >> >> >> >> >> >> >> >On Sun, 07 Dec 2008 05:29:26 -0800,bill.slomanwrote: >> >> >> On 7 dec, 09:25, Whata Fool <wh...(a)fool.ami> wrote: >> [snip] >> >>> Apparently atmospheric radiation is a big part of the total IR >> >>> radiation flux, and could that mean the atmosphere radiation controls >> >>> the temperature, not the surface radiation? >> >> >> Some of the infra-red radiation emitted by the ground and the ocean >> >> surfaces goes straight through the atmosphere (when the sky is clear) >> >> but the rest is repeatedly emitted and readsorbed by the greenhouse >> >> gases as it makes it way up through the amosphere; >> >> >Where there is water vapor and clouds, the atmosphere should behave as >> >a nearly black body of warm gas and convect accordingly. A steady state >> >should be reached where the heat radiated from the top is equal to the >> >heat coming into the bottom, else the bottom gas temperature would >> >increase and force convection to transport more heat to maintain >> >equilibrium. You can't "retain heat" in a gas without raising its >> >temperature. >> >> >> the height that it has to get to before it gets a clear shot at open >> >> space eventually determines the temperature at ground level. >> >> >That I agree with. How much CO2 and water respectively have to do with >> >that is the question. > >And one that you don't seem to be equipped to understand. > >> You should not agree with it, the temperature at ground level can >> be all time record world highs in a desert valley, and not because of >> more water vapor or CO2, > >No. The high temperatures in the desert valley during the day are >caused by solar radiation that goes straight through the air to hit >the ground, be absorbed and raise its temperature. Water vapour and >CO2 don't get into the act. At night the surface radiates like a hot >black body, and cools off rapidly; some of that infrared radiation is >absorbed by greenhouse gases in the air above and re-radiated back at >the ground, and some of it has a free ride to outer space. > >>or the temperature can be all time record lows >> at the South Pole and not because of less water vapor or CO2. > >No - the low winter temperatures at the South Pole are caused by the >total absence of incoming solar radiation during the winter, not that >the snow covered surface absorbs all that much solar radiation when >the sun is above the horizon. The surface would get even colder if it >wasn't for the greenhouse gases in the air above the pole so the do >have some effect - but there is not a lot of water vapour in the air >whne the temperature is down at -65C. > >http://en.wikipedia.org/wiki/South_Pole > >> In fact, the big changes in temperature occur with wind shift, >> and that has very little to do with water vapor or CO2. > >We are talking about global warming - which is to say the temperature >of the surface of the whole of the earth - not temperature differences >between different places on the surfce. > >> All that can really be said about water vapor and CO2 is that >> the atmosphere is cooler because of them, because GHGs cool the >> atmosphere. > >Which isn't actually true for the atmosphere as a whole. Greenhouse >gases determine the effective emitting altitude for the earth, where >the temperature has to be -14C to radiate enough power to balance the >power being absorbed from solar radiation. More greenhouse gases force >this altitude higher, and make the atmosphere a bit warmer - >specifically the laer closest to the ground. > >But Whata Fool isn't equipped to understand this, and keeps on >incanting his half-understood mantra. You should learn a little meteorology, the highest desert record temperatures occur because of descending air on very hot dry days. And it is the temperature of the air that is measured, not that of the ground, above a pond in the desert the air temperature will be cooler, not warmer. How many times are AGW disciples required to read and recite the myth in order to all speak the same tongue?
From: Whata Fool on 8 Dec 2008 15:23 bill.sloman(a)ieee.org wrote: >On 8 dec, 02:48, Whata Fool <wh...(a)fool.ami> wrote: >> Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: >> >> >Martin Brown wrote: >> >> >> Eeyore 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. >> >> >> You are clueless. That warmer air can carry more water vapour is a well >> >> known experimental fact. >> >> >You fail to address the idea it's an *amplifier*. >> >> >Graham >> >> Because it is obvious that more water vapor is a temperature moderator, >> and a very beneficial and effective one. >> >> All CO2 can do is absorb and emit, which can only cool the huge mass >> of the atmosphere, CO2 doesn't have enough mass to store or hold any thermal >> energy. > >Nobody claims that it does. Despite that, CO2 does manage to prevent >the bulk of the atmosphere losing heat by infra-red radiation at the >wavelengths that CO2 absorbs and re-emits. The details of this process >are little to complicated to be fitted into Whata Fool's picture of >the world, but that doesn't stop it from happening. > ><snipped the udual irrelevant guff> > >> It has to be that GHGs cool the N2 and O2, which is 98 percent of >> the mass of the atmosphere, so more GHGs should cool the atmosphere a >> little more. > >It might in Whata Fools version of reality, but not in real life. > >> The actual solid and liquid surface temperatures vary so much as >> a result of many factors, the "surface" temperature doesn't matter much >> during an interglacial period. > >If that's case, why are you complaining about the low surface >temepratures around your house at the moment? I'm not, at the moment, I did complain about the air temperature, air is a gas, the surface is rock and dirt.
From: Bill Ward on 8 Dec 2008 18:19 On Mon, 08 Dec 2008 06:22:33 -0800, John M. wrote: > On Dec 8, 11:29 am, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> On Mon, 08 Dec 2008 01:32:30 -0800, John M. wrote: >> > On Dec 8, 10:21 am, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> >> >> What would drive horizontal advection if not density differences and >> >> resulting vertical convection? >> >> > Coriolis. >> >> I believe that just changes the apparent direction of an already >> existing horizontal movement. > > Only if the observer is not part of the rotating system. For the Earth's > surface, the atmosphere can be regarded as an observer who is in the > system. It "sees " i.e experiences a real force, just as child on a > merry-go-round feels a real, outward, centrifugal force opposite in > direction to that noted by someone watching the rotation happen. > >> Nice try, though. > > Now you need to rethink this comment, don't you? Or is it still too much > for you to admit to making mistakes? Not my problem. You're projecting again: http://en.wikipedia.org/wiki/Fictitious_force "The surface of the Earth is a rotating reference frame. To solve classical mechanics problems exactly in an Earth-bound reference frame, two fictitious forces must be introduced, the Coriolis force and the centrifugal force (described below)." Fictitious force == "Not real". Are you now going to claim wiki is wrong on something so simple and clear cut? Either way, the initial horizontal movement can't occur without some sort of convection driven force, so you're still lost in the woods.
From: Bill Ward on 8 Dec 2008 18:33 On Mon, 08 Dec 2008 04:24:41 -0800, Martin Brown wrote: > On Dec 7, 7:55 am, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> On Sun, 07 Dec 2008 05:45:26 +0000, Don Klipstein wrote: >> > In article <pan.2008.11.29.05.49.04.133...(a)REMOVETHISix.netcom.com>, >> > Bill Ward wrote: >> >>On Fri, 28 Nov 2008 19:35:59 -0800, bill.sloman wrote: >> >> >>> 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. >> >> >>He may also be aware that increased water vapor lowers the >> >>condensation altitude, >> >> > Cloud bases lower if relative humidity rises. Relative humidity >> > stays about the same if water vapor concentration is only commensurate >> > with temperature rise. >> >> Interesting concept. I'm assuming the surface temperature determines >> the absolute humidity, and the condensation altitude would be determined >> by the lapse rate downward from the cloud tops (radiation layer). It >> seems to me the surface temperature varies a lot more than the higher >> altitudes. >> >> Is there any actual data on the altitude of the radiation layer that >> radiates the most power? From what I've seen, it's mid troposphere, not >> the tropopause. Are there any credible models of the individual >> mechanisms from cloud tops to the tropopause? >> >> >> raising the radiation temperature, and increasing the emitted IR >> >>energy by the 4th power radiation law. IOW, it's a negative >> >>feedback, not positive. >> >> > Radiation from cloud bases is toward Earth. >> >> I think that concept confuses people, at least me, when I first heard >> it. It appears at first glance you are claiming the cloud bases are >> warming the surface, which is clearly impossible by the second law. > > That depends on whether or not the cloud base is actually warmer than the > surface. It isn't all that common unless thick low cloud moves in quickly > after a previously clear still night sky where the ground has already > become substantially colder than the cloudbase. Typically the effect of > clouds at night is to prevent the ground from losing quite so much heat by > radiation to the roughly -70C effective sky brightness temperature. I think that's wat I said, so I won't argue. The point to remember is that the clouds seldom actually warm the surface. Emitters are always hotter than recievers, > >> The clouds are colder than the surface, and energy can never radiate >> from cold to hot. > > The lower levels of clouds can sometimes be warmer than the upward > facing ground. At the bottom layer where water vapour is condensing to > form liquid droplets there is latent heat being released. Where and how often does that happen? Is it significant to "global surface temperature"? >> A little more thought reveals the actual mechanism must be that some of >> the radiation that comes from the surface can be considered to be >> radiated back to maintain the (Tsource^4 - Ttarget^4) term in the >> Stefan-Boltzmann equation. That still requires that the net heat flow >> is outward, never inward (unless the surface is cooler). The upper >> layers may reduce the cooling rate of the surface, but they can never >> actually heat it. > > Depends if the surface has already got colder than the clouds first. I > suggest you wait for a suitable winters night that starts clear with a > frost and then has a warm front of cloud move in and watch the exterior > thermometer. If the surface is cooler than the cloud, yes. >> The _net_ radiation has to be from the surface to the clouds. > > Only if the clouds are cooler than the surface (which is usually the > case). Yes, that's my point. >> > Meanwhile, increasing GHGs cools the lower stratosphere and raises >> > the tropopause - cloud tops around the tropopause will be cooler. >> >> I'm not clear why. Could you explain why a cooler stratosphere raises >> the tropopause? Is it because the tropopause is the top of >> convection, so a colder stratosphere allows convection to continue >> higher before the UV-O2, O3 inversion takes over? > > Essentially yes. Warm air can rise higher before the boundary layer is > reached. > So long as the air above it is cooler it can keep on going up. So it's convecting into air that was formerly stratosphere, but is now defined as troposphere because of that very convection. OK. It seems something of a fine point, however.
From: Bill Ward on 8 Dec 2008 18:52
On Mon, 08 Dec 2008 04:32:48 -0800, Martin Brown wrote: > On Dec 8, 1:20 am, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: >> Martin Brown wrote: >> > Eeyore 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. >> >> > You are clueless. That warmer air can carry more water vapour is a >> > well known experimental fact. >> >> You fail to address the idea it's an *amplifier*. > > I would not use the word "amplifier" myself to describe what is actually a > positive feedback mechanism. But his meaning is clear and the physics are > baiscally correct more CO2 in the atmosphere makes it warmer and the extra > warmth allows more water vapour into the air before it saturates. Where does the latent heat in the water vapor come from? Where does it eventually go? > Warmer seas and warmer air over them will contain more water vapour as a > result. And more latent heat convection. |