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From: Bill Ward on 8 Dec 2008 03:36 On Mon, 08 Dec 2008 03:54:11 +0000, Don Klipstein wrote: > In <pan.2008.11.29.05.43.32.198332(a)REMOVETHISix.netcom.com>, Bill Ward > wrote in part: > >>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: >>>> >>>> > <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. > > What about in the majority of the troposphere lacking convection? And > how are cloud tops the effective radiating layer in the half of the world > that lacks clouds? It doesn't have to be everywhere, just in the places where most of the cooling takes place, such as the tropics. >> Above the radiating layer, there's not much CO2 left, > > Assuming Earth reflects half of solar radiation and has .95 emissivity > of low temperature thermal IR (the figure on my non contact > thermometer), Earth radiation achieve radiation balance at 237-238 K. (I > may have posted a few degrees lower before by forgetting the .95 > figure). 237 K is about -36 C. > > 237 K is when 95% of blackbody radiation intensity is 1/8 of the solar > constant. > > Average location of a photon radiated from Earth to outer space is > where > temp. is -36 C, but that is give-or-take a lot, since a lot of thermal > radiation can go some fair distance through the atmosphere before being > absorbed. > > On average, the altitude at which temperature is 237 K is around the > 300 > mb level, which has about 30% of the mass of the atmosphere above it. > However, a lot of photons radiated to space from Earth come from > greatly > different altitudes, some of which have more than 30% of the atmosphere > overhead. > >> and the 15u band is off peak, > > Peak wavelength of a blackbody at 237 K is around 12.5 um. At 15 um, > radiation is about 91% of that at peak wavelength. You are 18K lower than another similar analysis: http://www.atmos.washington.edu/2001Q1/211/notes_for_011001_lecture.html <begin excerpt> What does the emitted radiation tell us about the earth's temperature? We can calculate the temperature a black body would have to have in order to emit the same amount of radiation as the earth. This is called the effective radiating temperature. It's the temperature that would be measured by an infrared thermometer (radiometer)in outer space, pointed at the earth. How do we calculate the effective temperature? From the Stefan-Boltzmann Law which says that the emitted radiation is equal to a constant times the effective radiating temperature raised to the fourth power. To solve this equation, all we need to do is divide the emitted radiation (239.4 watts per square meter) by the constant (5.67 x 10 to the minus 8) and take the fourth root of the result. Dividing we obtain 42.2 x 10 to the eighth power. (We could also express this result as 4.22 x 10 to the 9th power, but since we're going to take the fourth root of this number, it's convenient to use a power of 10 that's divisible by 4.) We'll take the fourth root on a calculator, but to check it's a good idea to estimate the result by taking the square root of 50, which should be just about 7 and taking the square root of 7 which should be around 2.5. The fourth root of 10 to the eighth power is 100. Hence, the answer should be a number around 2.5 x 100 or 250. The calculated result is 255. Remember that all results obtained from the Stefan_Boltzmann Law and other radiation laws are expressed in degrees Kelvin, so this is 255 K (-18 C, 0 F). <end excerpt> and http://geography.berkeley.edu/ProgramCourses/CoursePagesFA2006/Geog40/L5.pdf That also comes up with 255K. If so, that would be lower in the atmosphere than your estimate, and would put the CO2 band further off the peak of the BB emission spectrum. It seems to me there should be enough satellite radiometer measurements to determine pretty closely what level is actually radiating at every spot on Earth. That would give a map of the areas that are actually cooling the Earth, and perhaps some insights into the mechanisms involved. Do you know why this hasn't happened? > > <Snip from here - will respond to other points in a separate post> > > - Don Klipstein (don(a)misty.com)
From: John M. on 8 Dec 2008 03:43 On Dec 7, 11:36 pm, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > Bill Ward wrote: > > Don Klipstein wrote: > > > > 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. > > The clouds are colder than the surface, and energy can never radiate from > > cold to hot. > > > 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. > > > The _net_ radiation has to be from the surface to the clouds. > > Absolutely. That's kinda basic physics ! > > I see the AGW crowd heading towards concepts more akin to the 'perpetual > motion' nuts. If the science doesn't support your case, then just make it up. You must be somehow unaware of a universal truth that TD and AGW derive from exactly the same endeavour - it's called science.
From: Whata Fool on 8 Dec 2008 03:44 Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >On Sun, 07 Dec 2008 21:02:17 -0500, Whata Fool wrote: > >> Bill Ward <bward(a)REMOVETHISix.netcom.com> wrote: >> >>>On Sun, 07 Dec 2008 05:29:26 -0800, bill.sloman wrote: [snip] >>>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. >> >> >> 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, or the temperature can be all time record lows at the >> South Pole and not because of less water vapor or CO2. > >The point I'm agreeing with is that the earth must radiate the same >energy it receives from the Sun, as a blackbody at about 255K. If you >take a lapse rate downward from the level at which that occurs, you should >arrive at the surface temperature. Of course, there are questions >regarding the altitude at which that occurs, the lapse rate to use, and >the net feedbacks involved. The surface and each layer of the atmosphere radiate at whatever temperature they are, however much, averaging it doesn't reduce radiation. >In the presence of an excess of H2O,It still isn't clear to me how anyone >can claim 390ppmv of CO2 will significantly affect the surface temperature >until those questions are answered. Ice core data shows CO2 following >temperature for several hundred thousand years. To me, it seems unlikely >that has suddenly reversed. > >I don't believe climate models as currently implemented have any >credibility at all in answering those questions. If anyone has any >specific, meaningful explanations, I'd be happy to see them. > >> In fact, the big changes in temperature occur with wind shift, >> and that has very little to do with water vapor or CO2. >> >> 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. > >At least in the daytime. All the time, it is the huge difference and amount of mass of N2 that holds the thermal energy, which it would hold even longer if it wasn't for GHGs. A good exercise for the continuing education of the climatologist would be to try to find all the sentences in the literature which say or infer that GHGs "warm" any part of the atmosphere when that part of the atmosphere would be retaining heat if it wasn't for GHGs. It really scares me that all the various sciences in geology allow misstatements to stand when extremists are calling for such things as lowering the thermostat, and I heard a rumor that laws someplace require a tenant to keep the thermostat at 68 in daytime in the heating season and 66 at night (or lower) if the landlord asks. It is important to get science right when asking billions of people to spend or give money for a cause.
From: John M. on 8 Dec 2008 03:47 On Dec 7, 10:56 pm, Whata Fool <wh...(a)fool.ami> wrote: > Q <q...(a)universe.com> wrote: > >Whata Fool wrote: > >> I would like to agree with GISS, but every error and other > >> embarrassment causes a loss of confidence. > > >There is no error in GISS, the only error is in the brains of those who > >deny anthropogenic global warming. AGW is real, get used to it. > > Oh, it sure is, 20 degrees below normal, that is real "warming". Not in Moscow it isn't.! 11°C when it should be -5°C. That's real "cooling"!
From: Whata Fool on 8 Dec 2008 03:52
don(a)manx.misty.com (Don Klipstein) wrote: >In <pan.2008.12.03.05.51.11.802525(a)REMOVETHISix.netcom.com>,B. Ward wrote: >>On Wed, 03 Dec 2008 04:14:23 +0000, Don Klipstein wrote: >> >>> In <pan.2008.11.26.21.52.54.243812(a)REMOVETHISix.netcom.com>, Bill Ward >>> said: >>>>On Wed, 26 Nov 2008 07:52:48 -0800, bill.sloman wrote: > ><I snip to edit for space arbitrarily on level of quotation/citation, >without snipping perfectly accurately on basis of degree of quotation> > >>>>> Don't be silly. I was being rude about the phrase "water and water >>>>> vapor IR radiation plus phase change _moderate_ the temperature" which >>>>> is total nonsense, as the Venus example demonstrates. >>>>> >>>>> You also need to apologse for not knowing what you are talking about. >>>>> >>>>>> Just say how N2 and O2 could cool after daytime heating and >>>>>> I will go away. >>>>> >>>>> They emit and absorb in the infra-red just like water and carbon >>>>> dioxide; because they are symmetrical molecules the transitions are >>>>> forbidden, but pressure broadening/intermolecular collisions means that >>>>> the transitions happen anyway, albeit much less often than with >>>>> asymmetrical molecules. >>>> >>>>I think we need a link for that. It would mean N2 and O2 are GHGs. >>> >>> I suspect to some extremely slight extent they actually are. >> >>Can you tell us why you suspect that? Perhaps a link to some data? > > On that point, I am feeling challenged to find links supporting a >contention that N2 and O2 have IR absorption spectrum features having any >significance at "earthly temperatures". > > Considering only global average surface temperature of 288-289 K, a >blackbody has spectral power distribution over 1% of peak over >wavelengths from about 3.4 um to about 66 um. > > Going so far as .1% of peak spectral power distribution of a 288 K >blackbody, the wavelength range is about 2.95 um to close to 100 um. > > Source: The "blackbody formula". > > I have strong doubt that the massive amounts of O2 and N2 in the >atmosphere completely lack any infrared spectral features in or shortly >outside such a range. > ><SNIP from here on basis of low level of content to show as quoted less >than twice> > > - Don Klipstein (don(a)misty.com) The N2 and O2 in the atmosphere are not dry. N2 would have very little infr-red if dry, and O2 would probably have a little more, but not worth mention, and definitely not enough to mean that the N2 and O2 in the Earth's atmosphere could cool themselves without GHGs. (without getting a lot warmer than present). |