The world has never seen such freezing heat
in [Design]
|
Prev: Class D audio driver with external mosfets
Next: NE162 mixer: input/output impedance in balanced mode?
From: Bill Ward on 30 Nov 2008 15:54 On Sun, 30 Nov 2008 07:13:33 -0800, bill.sloman wrote: > On 29 nov, 06:43, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: >> 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:> > > <big snip - Bill Ward does go in for mindless repetition> > >> > 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. > > The air at the effective radiating altitude is well below the freezing > point of water - the earth radiates as if it is a black body at -14C, and > while this is an average over all wavelengths (for wavelengths absorbed > and re-radiated by CO2 the temperature has to be closer to -55C) it makes > sense that the radiation appears to come from a layer where water vapour - > the predominant greenhouse gas - has condensed out. > > The partial pressure of water vapour above the cloud tops is too low to > convect any signficant latent heat higher You seem to be going to great lengths to repeat my points as though they were your own. I'll take that as a compliment. Once the cloud has condensed, its latent heat has radiated from the cloud tops, and has a clear shot to space. Above the cloud tops, WV is gone, radiation is effective, convection isn't needed. >> It's in the 10s of kW/m^2 compared to the 500W/m^2 max from surface >>radiation. > > It was at the surface, where the partial pressure of water vapour is > around 2300 Pa. The saturation vapour pressure has dropped to 603 Pa by > the time the temperature has dropped to zero Celcius. It drops off even > faster over ice, so it certainly isn't beating radiation at the > effective emitting altitude. Assume at the surface boundary layer we have a thermal with a given humidity and velocity. What do you think happens to a parcel of air, and the energy it contains, as it rises? Keep in mind that matter and energy are conserved. I can tell you, from direct observation, that it continues upward at a relatively constant velocity until it reaches either a change in the lapse rate, or the condensation altitude (cloud base). You need to rethink your position to include that easily verifiable fact. You also need to get out more. Try riding a sailplane in a thermal. > http://www.engineeringtoolbox.com/water-vapor-saturation-pressure-air-d_689.html > > http://www.answers.com/topic/dewpoint-jpg-1 > > http://faculty.matcmadison.edu/slindstrom/VaporPressure.doc Thanks for the supporting links. I may have posted a couple of them before. >>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. > > CO2 has both 5u and 15u absorbtion bands Please. Are you now claiming that the surface is radiating significantly in the 5u band? You're the radiation expert, what BB temperature would that represent? My BOE guess is about 300C, which seems a bit unrealistic for Earth, especially at the effective radiation altitude. Looks like you've reached the bottom of the barrel. > http://www.wag.caltech.edu/home/jang/genchem/infrared.htm > > What do you mean by "translucent"? Scattering rather than absorbing, like the frosted glass on a light bulb. I was humoring you. I suspect the lower troposphere is nearly opaque to the 15u band, and satellites are just seeing emission from the top layer. It doesn't matter either way to the argument. > CO2 absorbs and retransmits infra-red radiation at specific lines > within both bands, and this radiation won't have a "clear shot at space" > until it gets high in the stratosphere. How much? And how much difference does it make in view of the negative feedbacks involved in the convective transfer? Try considering the lower troposphere as a variable (temperature sensitive) thermal resistance and the region above the radiating layer as a relatively smaller, slightly CO2 sensitive resistance. > CO2 is also disproportionately effective at broadening water vapour > absorption lines, and this will be significant in the region close above > the cloud tops where there's still some partial pressure of gaseous > water to absorb and retransmit at water vapour's absorbtion lines. OK. Now use your radiative transfer model to compare that to the effect of warming (lowering) the emitting layer a few degrees. Don't forget the T^4 term. Sorry about the repetition, but it was worth it, since you have now apparently caught on to what I was saying. I'm more pragmatic than polite, I guess.
From: Martin Brown on 28 Nov 2008 09:03 Eeyore wrote: > > z wrote: > >> bill.slo...(a)ieee.org wrote: >> >>>>>> Besides, models only model LINEAR systems ! >>>>> Oh really? Then the Spice models of transistors (which exhibit an >>>>> expotential - not linear - relationship between base voltage and >>>>> collector current) don't exist. >>>> That IS a linear system as we describe them now. Who is "we" in this context? >>> This is a minority opinion. Any student sharing it with their examiner >>> would fail that aspect of their exam, but since you clearly exercise >>> your mind by believing six impossible things before breakfast I >>> suppose we can write this off as part of the price you pay to maintain >>> your genius-level IQ. >> well to be fair, he only said "linear"; could be he didn't mean the >> usual sense of "straight line" > > Quite so. A LINEAR equation can contain power, log, exp terms etc. > > But it CANNOT model CHAOS. And that's what weather and climate are. Rubbish. There are simple quadratic equations that model chaos. The most famous ones being the iterative equation in real variables 0 <= x, lambda <= 1 x[n+1] = lambda*x[n](1-x[n]) Mathlab have a nice demo of its behaviour as a function of x, lambda online at. http://library.wolfram.com/examples/iteration/ And the definig equation of the Mandlebrot fractal (z, c complex) z[n+1] = z[n]^2 + c Note that these are *very* simple almost minimalist equations giving rise to complex chaotic behaviour and exotic looking fractal details. Regards, Martin Brown ** Posted from http://www.teranews.com **
From: Martin Brown on 28 Nov 2008 09:17 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. And so is the opposite that dew or fog forms when the air temperature falls below the saturation point. http://intranet.st-peters.york.sch.uk/fileadmin/subjects/geography/GeogIntranet/HTMLpages/w_evap_con.htm Might just be within your capability to understand. Over the 70% of the Earth covered by oceans the effect of warmer air over the open sea is inevitably to increase the amount of water vapour entering the troposphere. It is these warmer waters evaporating that provide the power source needed for hurricanes and typhoons. Regards, Martin Brown ** Posted from http://www.teranews.com **
From: Whata Fool on 30 Nov 2008 21:48 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. 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 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.
From: Bill Ward on 30 Nov 2008 23:10
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. I don't think Trenbuth's method of estimating latent heat from estimated total precipitation is correct. It ignores virga, recirculation in deep convection, and all the other ways that clouds can evaporate without falling to the ground. 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. I think the existence of a near-adiabatic lapse rate guarantees it. >>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. I'm not sure how relevant it is, but it's an interesting question. |