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From: Don Klipstein on 3 Dec 2008 22:45 In article <pan.2008.11.30.21.41.11.102553(a)REMOVETHISix.netcom.com>, Bill Ward wrote: >On Sun, 30 Nov 2008 07:28:18 -0800, bill.sloman wrote: > >> On 29 nov, 21:38, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >>> On Sat, 29 Nov 2008 09:58:21 -0800, bill.sloman wrote: >>> > On 28 nov, 16:55, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: <SNIP deeper levels of quotation> >>> >> That needs a little explanation. CO2 gas is not a BB radiator. At >>> >> the temperatures in question, the 15u band should be the only >>> >> radiation it can absorb or emit. How do you come to the conclusion >>> >> it emits in a -55C BB spectrum? Do you have a link supporting that? >>> >>> > I didn't say that it emitted a black body spectrum. It emits the same >>> > spectrum as any volume of carbon dioxide at 218K would, which is >>> > different from the spectrum emitted by warmer carbon dioxide. >> >> What I should have said here is that the radiation it does emit has the >> same intensity as a blackbody radiator would emit at that temperature. >> >> This follows from the second law of thermodydnamics - if it wasn't so a >> blob of CO2 surrounded by a blackbody would end up at a temperature other >> than that of the blackbody. >> >>> You said, "a spectrum that matches the roughly -55C temperature of the >>> bulk of the stratosphere", not a "218K CO2 spectrum". >> >> Same thing. > >Isn't the CO2 absorption/emission spectrum a band, not a BB distribution? >In part of your previous post (which you snipped) you linked to this: > >http://www.wag.caltech.edu/home/jang/genchem/ir_img7.gif That appears to be a sampling of a layer of CO2 representing less CO2 than one has to pass through from surface to outer space. Another version of CO2 IR spectrum is at: http://www.iitap.iastate.edu/gccourse/forcing/images/image7.gif http://www.iitap.iastate.edu/gccourse/forcing/spectrum.html >It doesn't look like a BB to me. Are you having trouble keeping your >stories straight again? But CO2 is close to blackbody within some range of wavelengths where emission is close to eak of a 218 K blackbody. And the range does widen somewhat when there is more CO2 in the atmosphere. >>> > This follows from the second law of thermodynamics. The fact that the >>> > 218K spectrum is going to be different from the spectrum emitted by a >>> > warmer lump of gas depends on the proposition that the numbers of >>> > molecules occupying higher energy vibrational and rotational quantum >>> > states changes with temperature, and it is this distribution across >>> > the accessible quantised energy levels that dictates the shape of the >>> > emission spectrum. > >The "lump" would need to absorb and emit just enough to stay in thermal >equilibrium. Why would the general spectrum suddenly change? What you are >saying doesn't make sense to me. Please explain. > >>> Outside the 15u band? How much difference is there between the energy >>> in the spectra at the two temperatures? >> >> http://en.wikipedia.org/wiki/Black_body >> >> work it out for yourself. > >Let me rephrase: I don't think there's a significant difference. Show >why you think there is. Start by showing why you think it's a BB >distribution. CO2 acts fairly like a blackbody at wavelengths within the 15 um band. 15 um is a wavelength where a blackbody has spectral power distribution about 96% of peak. - Don Klipstein (don(a)misty.com)
From: Don Klipstein on 3 Dec 2008 23:13 In article <9n56j4d7lcc39lifls7c1vrgr6bmc00skn(a)4ax.com>, Whata Fool wrote: <SNIP to here> > He is confusing me, doesn't the AGW consensus claim that AGW has >caused the stratosphere to cool to a lower than normal temperature? Yes, it does. Yet, that does not negate warming of the surface and lower atmosphere. <SNIP greater level of quotation> > Haven't all measurements shown that the stratosphere has cooled, >and that added CO2 concentration [AGW] caused it? Yes that is true, without negating warming of the surface and lower troposphere. >>>> Outside the 15u band? How much difference is there between the energy >>>> in the spectra at the two temperatures? >>> >>> http://en.wikipedia.org/wiki/Black_body >>> >>> work it out for yourself. >> >>Let me rephrase: I don't think there's a significant difference. Show >>why you think there is. Start by showing why you think it's a BB >>distribution. > > That page contains the following sentence; > >"This is the black body temperature as measured from space, while the >surface temperature is higher due to the greenhouse effect." > > I claim, and strongly suggest that thinking scientists must understand >that statement does not represent the true physics, because it ignores the >probability that an N2 and O2 (78 + 20) atmosphere would be hotter than at >present without GreenHouse Gases. Upper layers of the atmosphere would indeed be warmer if GHGs were reduced. > Unless somebody can explain how N2 and O2 could cool after being >warmed by solar energy and convection from the surface. If there was complete lack of GHGs and clouds, lower troposphere would be in thermal equilibrium with the surface. Average temperature, or somehow-appropriately-weighted-average temperature of the near-surface troposphere and the surface would be the same. Wind would cause trubulence causing forced convection, resulting uin a lapse rate to some sort of tropopause that would be much lower than the one we have now. ================================= With the atmosphere having better thermal contact with the surface at warmer times of the day, I expect that some altitude maybe 500-1000 feet has daily average temperature less than that of the surface where surface temperature varies a lot throughout the day - due to being more insulated from the surface at cooler times of the day and more thermally connected to the surface at hotter times of the day. Much up from there, it's average lapse rate (determined by vertical convection and effective large-region-with-thorizontal-temperature-gradient-convection in baroclinic areas/events) up to the tropopause. Above the tropopause, maybe moderated by the bit of flow through discontinuities of the tropopause, it's radiation balance. Any atmospheric layer above the tropopause with absorption of non-IR output from the Sun being strong in comparison to any IR radiating ability can get quite hot - and that does indeed occur in Earth's thermosphere. - Don Klipstein (don(a)misty.com)
From: Don Klipstein on 3 Dec 2008 23:30 In <pan.2008.12.01.00.23.21.593448(a)REMOVETHISix.netcom.com>, B. Ward said: >On Sun, 30 Nov 2008 18:02:11 -0500, Whata Fool wrote: > >> Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >> >>>On Sun, 30 Nov 2008 07:28:18 -0800, bill.sloman wrote: <And I snip most previously quoted material to edit for space> >>>> >>>> What I should have said here is that the radiation it does emit has the >>>> same intensity as a blackbody radiator would emit at that temperature. >>>> >>>> This follows from the second law of thermodydnamics - if it wasn't so a >>>> blob of CO2 surrounded by a blackbody would end up at a temperature >>>> other than that of the blackbody. >>>> >>>> <SNIP response to snipped point> >>> >>>Isn't the CO2 absorption/emission spectrum a band, not a BB distribution? >>>In part of your previous post (which you snipped) you linked to this: >>> >>>http://www.wag.caltech.edu/home/jang/genchem/ir_img7.gif >>> >>>It doesn't look like a BB to me. Are you having trouble keeping your >>>stories straight again? >> >> >> >> He is confusing me, doesn't the AGW consensus claim that AGW has >> caused the stratosphere to cool to a lower than normal temperature? >> >>>The "lump" would need to absorb and emit just enough to stay in thermal >>>equilibrium. Why would the general spectrum suddenly change? What you >>>are saying doesn't make sense to me. Please explain. >> >> Haven't all measurements shown that the stratosphere has cooled, >> and that added CO2 concentration [AGW] caused it? >> >>>>> Outside the 15u band? How much difference is there between the >>>>> energy in the spectra at the two temperatures? >>>> >>>> http://en.wikipedia.org/wiki/Black_body >>>> >>>> work it out for yourself. >>> >>>Let me rephrase: I don't think there's a significant difference. Show >>>why you think there is. Start by showing why you think it's a BB >>>distribution. >> >> That page contains the following sentence; >> >> "This is the black body temperature as measured from space, while the >> surface temperature is higher due to the greenhouse effect." >> >> I claim, and strongly suggest that thinking scientists must >> understand >> that statement does not represent the true physics, because it ignores the >> probability that an N2 and O2 (78 + 20) atmosphere would be hotter than at >> present without GreenHouse Gases. >> >> Unless somebody can explain how N2 and O2 could cool after being >> warmed by solar energy and convection from the surface. > >I suspect the equatorial to polar temperature gradient would invoke >convection bands that would tend to equalize the temperatures by >conduction to the surface. The nighttime surface would be colder then the >adjacent atmosphere, the daytime would be hotter and, "on the average", it >looks to me like the (lower) atmosphere still might be warmer than the >surface, because of the day/night asymmetry in convection. That does indeed occur. >I think adding GHG's with no latent heat would overall cool the atmosphere >and warm the surface via the nighttime IR blanket effect. That is indeed true. > But I also think that on Earth, latent heat transport by water >overwhelms any IR warming by CO2 >If someone has a lucid explanation showing otherwise, I'd like to see it. Could well be greater, without negating significance of warming of surface and lower levels of the atmosphere by CO2. Also consider that significant heat transport by atmospheric movement is not latent heat. Just as an example of an extreme - cyclones of baroclinic nature (the "usual extratropical cyclone") where water vapor presence is low. Such things do occue in central and northern Canada in mid and late winter, when water vapor presence is low enough to not account for much heat movement. Such things do occur in desert areas. They even occur on Mars without a cloud anywhere. I remember a demonstration by a Sunday School teacher showing baroclinic cyclones and baroclinmic events in general forming without latent heat - in a big pot of water on a record player turntable, with red food dye dropped in over the circumference, and blue dye dropped in at the center - and then heat the circumference with a propane torch. Baroclinic events result in global or regional convection and heat transport across latitudes through the otherwise-barrier of local lapse rate being short of allowing local vertical convection. - Don Klipstein (don(a)misty.com)
From: Don Klipstein on 4 Dec 2008 00:03 In article <psi6j49cqlurimac886ehmsgcko2851rmp(a)4ax.com>, Whata Fool wrote: >Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: > >>On Sun, 30 Nov 2008 18:02:11 -0500, Whata Fool wrote: >> >>> Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >>> >>>>On Sun, 30 Nov 2008 07:28:18 -0800, bill.sloman wrote: >>>>>[snip] >>>>> http://en.wikipedia.org/wiki/Black_body >>>>> >>>>> work it out for yourself. >>>> >>>>Let me rephrase: I don't think there's a significant difference. Show >>>>why you think there is. Start by showing why you think it's a BB >>>>distribution. >>> >>> That page contains the following sentence; >>> >>> "This is the black body temperature as measured from space, while the >>> surface temperature is higher due to the greenhouse effect." >>> >>> I claim, and strongly suggest that thinking scientists must >>> understand >>> that statement does not represent the true physics, because it ignores the >>> probability that an N2 and O2 (78 + 20) atmosphere would be hotter than at >>> present without GreenHouse Gases. >>> >>> Unless somebody can explain how N2 and O2 could cool after being >>> warmed by solar energy and convection from the surface. >> >>I suspect the equatorial to polar temperature gradient would invoke >>convection bands that would tend to equalize the temperatures by >>conduction to the surface. > Not in the short time of 8 to 16 hours, there would likely be very >strong torus wind low up in the tropics and down near the poles, but even >with 500 MPH winds, there would only be time for one rotation or less, >and not enough mixing. Temperature gradient from poles to tropics causes baroclinic events, notably including the usual "extratopical cyclones". Where lapse rate gets low enough to impair such events, strong torus wind patterns do develop - the "polar vortices" / "polar vortex". > Remember, in air [after the gas properties are established] the >speed of sound depends on temperature. > >>The nighttime surface would be colder then the >>adjacent atmosphere, the daytime would be hotter and, "on the average", it >>looks to me like the (lower) atmosphere still might be warmer than the >>surface, because of the day/night asymmetry in convection. > > The fraction of thermal energy the rocky surface could take back >at night would not be enough to stabilize temperature below the present >atmospheric temperatures. There is some tendency for atmosphere at some lower altitude (maybe 500-1000 feet above surface) to have average temperature throughout each day to exceed that of surface-level-atmosphere (as measured at 4 feet or 2 meters above surface), in regions where surface temperature varies more throughout each day. > The surface radiation would be more time constrained than the >present atmospheric radiation that can take place at all levels in all >directions at the same time. ????? - can you explain that one? >>I think adding GHG's with no latent heat would overall cool the atmosphere >>and warm the surface via the nighttime IR blanket effect. > > That is a different scenario than the present Earth Same as the present Earth > or the Earth with NO GHGS, which AGW mistakenly assumes would be as cold >as the moon. Assuming as an oversimplification, Earth having 50% albedo to solar radiation and 95% emissivity at "low temperature thermal IR" wavelengths, and completely transparent atmosphere, and "solar constant" being 1366 watts per square meter, the "appropriately weighted" (4th power of mean 4th root) average global temperature would be close to 237 K, which is -36 C. And should the world get that cold, greater ice cover would make the albedo much higher and supporting even colder surface temperature. > The correct physics of an Earth with N2 and O2 atmosphere and >NO GHGs is required before comparing with the present Earth and the >premise of a warming GreenHouse effect. >>But I also >>think that on Earth, latent heat transport by water overwhelms any IR >>warming by CO2 > My opinion is that you are overestimating latent heat transport, >and that most convection is simply warm air convection (outside storm >regions). Response to someone who in this thread has generally been arguing against existence of AGW. >>If someone has a lucid explanation showing otherwise, I'd like to see it. > > I don't see how any AGW proponent can say that the Earth's atmosphere >is warmer now than it would be with NO GHGs at all, to do that they would >have to show how the N2 and O2 would be cooled after solar heating and >convection from the rocky surface. If there was no cooling of troposphere by radiation, then not too far up from any location in question the average daily temperature would indeed approach the average daily high temperature of the surface - as determined by radiation balance. Any wind would force turbulence causing "forced convection" up to whatever altitude results in a tropopause that becomes the limiting factor in altitude of such convection. Top level of such a troposphere is cooler than lower level since such convection requires a lapse rate - otherwise wind would only exist much above the surface and probably be mainly zonal (largely parallel to lines of latitude). (An infinitely thermally conductive blackbody such as a small ideal sphere of best-surface-blackened aluminmum in Earth's orbit would have temperature 5-6 degrees C above freezing. Keep in kind that Earth as a whole including its atmosphere is closer to being a blackbody at longer thermal-IR wavelengths and less of one at most wavelengths where solar radiation is stronger - meaning that Earth should be colder than 4-6 degrees above freezing if not for GHG. The 1950-1980 and 1930-1980 averages of Earth surface temperature were cloase enough to 15 degrees C.) - Don Klipstein (don(a)misty.com)
From: Don Klipstein on 4 Dec 2008 00:31
In <pan.2008.12.01.04.10.31.763123(a)REMOVETHISix.netcom.com>, Bill Ward said: >On Sun, 30 Nov 2008 21:48:14 -0500, Whata Fool wrote: > >> Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >> >>>On Sun, 30 Nov 2008 18:02:11 -0500, Whata Fool wrote: >>> >>>> Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >>>> >>>>>On Sun, 30 Nov 2008 07:28:18 -0800, bill.sloman wrote: >>>>>>[snip] >>>>>> http://en.wikipedia.org/wiki/Black_body >>>>>> >>>>>> work it out for yourself. >>>>> >>>>>Let me rephrase: I don't think there's a significant difference. Show >>>>>why you think there is. Start by showing why you think it's a BB >>>>>distribution. >>>> >>>> That page contains the following sentence; >>>> >>>> "This is the black body temperature as measured from space, while the >>>> surface temperature is higher due to the greenhouse effect." >>>> >>>> I claim, and strongly suggest that thinking scientists must >>>> understand >>>> that statement does not represent the true physics, because it ignores >>>> the probability that an N2 and O2 (78 + 20) atmosphere would be hotter >>>> than at present without GreenHouse Gases. >>>> >>>> Unless somebody can explain how N2 and O2 could cool after being >>>> warmed by solar energy and convection from the surface. >>> >>>I suspect the equatorial to polar temperature gradient would invoke >>>convection bands that would tend to equalize the temperatures by >>>conduction to the surface. >> >> Not in the short time of 8 to 16 hours, there would likely be very >> strong torus wind low up in the tropics and down near the poles, but even >> with 500 MPH winds, there would only be time for one rotation or less, and >> not enough mixing. > >One rotation of what per what? >> >> Remember, in air [after the gas properties are established] the >> speed of sound depends on temperature. >> >>>The nighttime surface would be colder then the adjacent atmosphere, the >>>daytime would be hotter and, "on the average", it looks to me like the >>>(lower) atmosphere still might be warmer than the surface, because of the >>>day/night asymmetry in convection. >> >> The fraction of thermal energy the rocky surface could take back >> at night would not be enough to stabilize temperature below the present >> atmospheric temperatures. >> >> The surface radiation would be more time constrained than the >> present atmospheric radiation that can take place at all levels in all >> directions at the same time. >> >>>I think adding GHG's with no latent heat would overall cool the >>>atmosphere and warm the surface via the nighttime IR blanket effect. >> >> That is a different scenario than the present Earth or the Earth >> with NO GHGS, which AGW mistakenly assumes would be as cold as the moon. >> >> The correct physics of an Earth with N2 and O2 atmosphere and >> NO GHGs is required before comparing with the present Earth and the >> premise of a warming GreenHouse effect. >> >>>But I also think that on Earth, latent heat transport by water >>>overwhelms any IR warming by CO2. >> >> My opinion is that you are overestimating latent heat transport, >> and that most convection is simply warm air convection (outside storm >> regions). > >If you look at a satellite image, you'll notice a lot of clouds. Many, >especially in the tropics, came from convection of humid air. Close to half the world lacks clouds, some of the clouds are stratiform and lacking local vertical convection, and some of the clouds are deeper semi-stratiform ones with local vertical convection over only some of their depth. In addition, over a significant portion of clouds whose tops indicate convection is clear air within the troposphere with local lapse rate significantly less than the dry adiabatic lapse rate. > I don't >think Trenbuth's method of estimating latent heat from estimated total >precipitation is correct. It ignores virga, Cools the air something like 1 km below the cloud while the cloud is a localized heating event at the range of altitudes where it exists > recirculation in deep convection, Hest transfer is within a smaller localized region > and all the other ways that clouds can evaporate without falling to the >ground. Without precipitation - clouds being evaporated generally have to manage to be in descending air - whether in some little region of a baroclinic event, within an extremely localized portion of a storm having convection generally vertical rather than baroclinic (the latter generally has airflow within 1 degree of horizontal). Main way for a cloud to be "evaporated" by precipitation - its mass throughout being at a temperature with great difference between the water vapor pressure over ice and water vapor pressure over supercooled liquid water. When some range of altitude of the troposphere supports convection, mainly I see that occurring where the precipitation is snow. And when spring is well-sprung, I find the atmosphere being more-clear of snow and snowy-virga when the covective clouds responsible for such pop up than within winter. >We've discussed the immense power density available in updrafts, so I >think there's some burden now to explain how there can be updrafts >_without_ transporting a lot of latent heat. Tornadoes, hurricanes, supercells and thunderstorms cover very little of Earth. > I think the existence of a near-adiabatic lapse rate guarantees it. Except that the global average tropospheric lapse rate is close to the "wet adiabatic" one, while close to half the world has troposphere lacking clouds at any altitude. Much of the other half has cloud presence excluding much or even most of the troposphere. Furthermore, there is significant presence worldwide of lapse rate being below even the "wet adiabatic" one that approximates worldwide troposphere - half of the world has lapse rate less than whatever average! <I snip past that on basis of lower relevance> - Don Klipstein (don(a)misty.com) |