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: Don Klipstein on 9 Dec 2008 02:31 In article <nb99j49210h2hir127luhvf7fh57u6jg4k(a)4ax.com>, Whata Fool wrote: >don(a)manx.misty.com (Don Klipstein) wrote: > >>In article <492d7873$0$87074$815e3792(a)news.qwest.net>, Al Bedo wrote: >>>bill.sloman(a)ieee.org wrote: >>>[regarding orbital variation with feedback] >>> >>>> The point is that we need a healthy dose of positive feedback to make >>>> the explanation work and similar positive feedback mechanisms could >>>> turn today's barely significant global warming into an end-Permian >>>> style global extinction. It isn't a high probability scenario, but we >>>> are taling about the only planet we've got. >>> >>>So what feedback are you suggesting? >>> >>>Not ice/albedo feedback of the glacials since that ice >>>extended to mid-latitudes where there was enough insolation >>>to matter. >> >> Insolation at even the North Pole in late spring is very significant. >>Have a look at 1366 watts times sine of 23 degrees, 24 hours a day. And >>only 2.35 times as much atmosphere to go through as when sun is at zenith. >> Ice melt in the Arctic matters a lot in the second half of spring and >>the first half of summer. >> >> The Antarctic also has seasonal sea ice - though more stable than that >>of the Arctic, since minimum late summer extent of Antarctic sea ice is >>close to nonexistent. Changes in Arctic sea ice carry into the next year. >> >>>Not water vapor feedback because that doesn't seem to be occurring. >> >> It did as the Ice Ages surged and ebbed. The thermal time constant of >>the oceans is a century or two - I think a degree rise sustained for a few >>decades will produce a measurable increase in atmospheric water vapor >>worldwide. >> >>>What then? >> >> Both those, along with ability of oceans to dissolve CO2 decreasing as >>they warm. Add up those 3 positive feedbacks, and their combined effect >>to amplify effects of the Milankovitch cycles was apparently great. >> >><SNIP from here> >> >> - Don Klipstein (don(a)misty.com) > > The oceans don't need to dissolve CO2 to remove it from the air, >there is enough carbonate life and algae to handle pretty much all that >man is releasing. Provided biomass and carbonates are actually increasing. Acid rain actually turns carbonates to CO2 and salts, and I don't see much evidence that biomass is increasing - more like a little of the reverse due to greater harvesting and burning. > If forests were harvested before they burn, it could help a lot, >and when/if ethanol or butanol or biodiesel is made from cellulose, that >will help. > > Every little thing can help, and an important one is battery and >ultracapacitor technology for electric cars. > > As if a mere 388 parts per million could make a big difference. :-) We're worrying for one thing about what happens if continued burning of fossil fuels gets that up to 500 ppm or more. CO2 has weak but very slightly significant absorption features at wavelengths where thermal IR from Earth's surface is great and where water vapor does not absorb much. Making those stronger does not look like a good thing now. - Don Klipstein (don(a)misty.com)
From: Martin Brown on 9 Dec 2008 04:34 On Dec 8, 11:19 pm, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: > 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 Yes. Your interpretation of Wiki is hopelessly wrong in this case. The "fictitious forces" are essential if you want to pretend that the Earth is a non-rotating reference frame for ease of calculation - they are a direct consequence of conservation of angular momentum. If you are going around a tight corner it is those "fictitious forces" that you feel. You can if you wish do the entire calculation in a true inertial frame and then the "fictitious forces" vanish but the mathematics becomes a more complex since you are moving with the surface of the Earth even when you think you are standing still. The pseudo-forces provide a way to handle dynamics in a rotating frame of reference more easily. They can be derived from consideration of conservation of angular momentum. You can also do the same calculations in the rotating frame of reference and see the fictitious forces appear as a result of the coordinate transformation and its dervivatives. People who worked on early radar in the hut with the rotating antenna had plenty of stories of working in a local frame of refernence where these "fictitious forces" were significant. The simplest example that is accessible to common sense reasoning is in long range gunnery and gunnery tables have been notoriously wrong in doubling the Coriolis error in the Southern hemisphere as recently as the Falklands war. It is left as an excercise to the reader to figure out why it makes a difference. Regards, Martin Brown
From: Martin Brown on 9 Dec 2008 04:52 On Dec 8, 8:03 pm, Whata Fool <wh...(a)fool.ami> wrote: > Martin Brown <|||newspam...(a)nezumi.demon.co.uk> wrote: > > >On Dec 8, 8:52 am, Whata Fool <wh...(a)fool.ami> wrote: > >> d...(a)manx.misty.com (Don Klipstein) wrote: > > >> >In <pan.2008.12.03.05.51.11.802...(a)REMOVETHISix.netcom.com>,B. Ward wrote: > >> >>On Wed, 03 Dec 2008 04:14:23 +0000, Don Klipstein wrote: > > >> >>> In <pan.2008.11.26.21.52.54.243...(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 (d...(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).- Hide quoted text - > > >Utter and unmitigated bullshit!! > > >A pure N2 and O2 atmosphere would develop strong winds of the type > >seen on the gas giants driven by the temperature and pressure > >differentials on the night and daytime sides of the planet. The > >atmosphere would lose heat by winds blowing from the cold regions at > >the anti-solar point to the warm sunny side. Where the air would take > >heat from the hot surface and rise genrating a circulation pattern. > >The surface gets to radiate IR away easily at night since we have > >already established that to a very good approximation they are > >transparent to IR. > > Try to break away from the myth, if you really believe the > above show some math with wind velocity, distance traveled in the > half day periods, and explain how to get the hot N2 to contact the > ground or colder N2 that would hug the ground. There will be the hottest ground and hot N2 rising from it soon after the sun has passed directly overhead and the coldest ground at the poles with a second cold band just before dawn on the night side of the planet. The overall circulation would probably be similar to Earths for a similar choice of planet weight, day length and position. http://www.srh.noaa.gov/srh/jetstream/global/circ.htm Strongest daily winds would be across the dawn terminator where the temperature gradient is at its most extreme. Jestreams can manage quite respectable speeds of the order of 300km/hr on Earth and they would probably be faster still on a planet that lacks any GHGs and so supports a larger temperature differential. > > Regardless of how much cooling there would be, the N2 temperature > would be higher than at present. > > A link to any study of the scenario would help erase the myth.. No one else in the world shares your delusions about GHGs. Not even other AGW sceptics. Regards, Martin Brown
From: kT on 9 Dec 2008 04:57 Martin Brown wrote: > The simplest example that is accessible to common sense reasoning is > in long range gunnery and gunnery tables have been notoriously wrong > in doubling the Coriolis error in the Southern hemisphere as recently > as the Falklands war. It is left as an excercise to the reader to > figure out why it makes a difference. Actually, that was World War I, and it's a myth upon first inspection. http://www.mememachinego.com/2004/09/the_coriolis_force_attracts_my.html
From: bill.sloman on 9 Dec 2008 09:58
On 9 dec, 01:55, Bill Ward <bw...(a)REMOVETHISix.netcom.com> wrote: > On Mon, 08 Dec 2008 07:15:34 -0800,bill.slomanwrote: > > On 8 dec, 05:42, d...(a)manx.misty.com (Don Klipstein) wrote: > >> In article <tqb3j4pmpsqj32hes94kb9pni1vaup6...(a)4ax.com>, Whata Fool > >> wrote: > >> >bill.slo...(a)ieee.org wrote: > > >> >>On 28 nov, 21:43, Whata Fool <wh...(a)fool.ami> wrote: > >> >>> bill.slo...(a)ieee.org wrote: > >> >>> >On 27 nov, 23:02, Whata Fool <wh...(a)fool.ami> wrote: > >> >>> >> bill.slo...(a)ieee.org wrote: > >> >>> >> >On 27 nov, 02:59, Whata Fool <wh...(a)fool.ami> wrote: > >> >>> >> >> "DeadFrog" <DeadF...(a)Virgin.net> wrote: <snip> > >> > The CO2 spectra is mostly narrow spikes, and supposedly > >> >those spikes are pretty much fixed to a certain range of temperatures, > >> >show any reference that suggests otherwise. > > >> The 15 um band of CO2 looks fairly broad here, comparable to the 2 > >> broader water vapor bands at 6 and 2.5 um: > > >>http://www.iitap.iastate.edu/gccourse/forcing/images/image7.gif > > > This spectrum covers a wide range of wavelengths, and doesn't ressolve the > > rotational fine structure. > > I've not had much luck finding spectra that do show the fine structure. > > > The best I've been able to do is here > > >http://www.anl.gov/PCS/acsfuel/preprint%20archive/Files/35_3_WASHINGT... > > > and since the pdf was generated by scanning a printed document, the > > figures at the end of the document are none too clear. > > >> > Actually, water vapor is almost BB at certain temperatures, > >> >that can't be said for CO2. > > >> Water vapor has significant gaps. > > >> Same source: > >> http://www.iitap.iastate.edu/gccourse/forcing/images/image7.gif > > >> >>as it gets colder the number of phtotons emitted at shorter wavelegths > >> >>goes down faster than the number emitted at longer wavelengths, which > >> >>implies something rather from your "the frequency is determined by > >> >>temperature". > > >> > Exactly, so the net energy transfer is a function of relative > >> >temperature differences, say it anyway you want, but 388 parts per > >> >million is a very small amount. > > > But quite enough to repeatedly absorb and re-emit all the radiation at the > > CO2 wavelengths as it goes through the atmosphere. > > Now what happens to the IR when it's absorbed? In the first instance, it raises the vibrational mode of the absorbing molecule to the next vibrational quantum level and - almost always - changes the rotational excitation. The extra energy gets redistributed between vibrational, rotational and translational degrees of freedom as soon as the molecule hits another, which happens pretty soon (though sooner in the higher pressures of the lower atmosphere than in the lower pressures and densities of the higher atmosphere) > It goes to heat. Heat convects. That "re-radiation" bit is bogus. Wrong.Every CO2 molecule in a first excited vibrational state has a chance to decay to the ground state by emitting a photon. For the asymmetric stretch and the bending mode the chance is high enough to be important at every level in the atmosphere. At any temperature above absolute zero there are always some molecules in the first excited vibrational states (though the numbers drop rapidly with decreasing temperature). Convection depends on the difference in densty between the warm gas and its cooler neighbours, and ceases to be a significant mode of heat transfer when the Raleigh number is less than 60, which it won't be near and above the tropopause, where radiative heat transfer at the CO2 spectral lines begins to get interesting >The gas is the same as any > other, just warmer, and maintaining radiative equilibrium. I'm surprised > you fell for that pinball explanation of radiative transport. IR travels > at c. When it's converted to heat, it warms the gas, and allows > convection to take place as soon as the lapse rate allows. The fact that you have difficulties with the "pinball" explanation of radiative heat transfer reveals that you are no better equipped than Whata Fool to understand the details of the greenhouse effect. > > One gram of potassium cyanide is only a small fraction of your body > > weight - 14.3ppm - but it is more than enough to kill you rapidly. > > Irrelevant, and a sure sign of desperation. No more irrelevant than Whata Fools complaint that 388ppm of carbon dioxide in the atmosphere was not enough to do anything. By the same - defective - logic 1 gram of potassium cyanide isn't enough to do anything either. If you don't agree with the argument I'd suggest tht you try the experiment. Bear in mind that if Whata Fool's logic doesn't hold up, you will end up dead. His misconceptions about the effects of greenhouse gases could be equally lethal, if taken seriously though the deaths won't start happening for a couple of centuries. -- Bill Sloman, Nijmegen |