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From: columbiaaccidentinvestigation on 15 Dec 2008 00:11
On Dec 14, 9:10 pm, Bill Ward <bw...(a)REMOVETHISix.netcom.com>
wrote:"If warm wet air is going up, and cold, dry air is going down"


sounds like you are describing a wave motion in a fluid eh bill, oops
better not say gravity waves.....
From: Don Klipstein on 15 Dec 2008 00:58
In article <pan.2008.12.08.07.58.38.490710(a)REMOVETHISix.netcom.com>, Bill
Ward wrote:
>On Mon, 08 Dec 2008 03:35:34 +0000, Don Klipstein wrote:
>
>> In article <pan.2008.11.27.19.50.55.98497(a)REMOVETHISix.netcom.com>, Bill
>> Ward 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:
>>>> <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 trophosphere 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 can
>>>> do anything.
>>>
>>>Where did I say the radiation all comes from a thin layer? You must be
>>>misinterpreting the concept of effective radiating altitude.
>>>
>>>
>>>>> >> IR radiated from the surface would be quickly absorbed by WV,
>>>>> >> clouds, CO2, and other GHGs, and at 500W/m^2 would be overwhelmed
>>>>> >> by the 10's of kW/m^2 available from convection of latent heat.
>>>>>
>>>>> > Clouds scatter infra-red radiation rather than absorbing it. as do
>>>>> > the greenhouse gases, but that's enough to sustain a thermal
>>>>> > gradient.
>>>>>
>>>>> Surely you're not proposing the lapse rate is sustained by outgoing
>>>>> IR. All the sources I've seen say the troposphere is due to
>>>>> convection, not radiation.  Can you find one to the contrary.
>>>>
>>>> Don't have to. Convection and transport as latent heat both decrease
>>>> rapidly as you move up through the troposphere, and radiation
>>>> progressively takes over, becoming responsible for 100% of the heat
>>>> transfer by the time you get to the tropopause. This is clearly implied
>>>> by what I wrote earlier (which is why I've not snipped it).
>>>
>>>So you don't really understand convection or radiation. If you did, you
>>>might see that radiation could not generate a "thermal gradient".
>>>Radiation tends to equalize temperatures, you know. It's described by all
>>>that second law stuff you must have somehow skipped over.
>>
>> Radiation alone can generate a thermal gradient.
>
>That seems to me to be against the second law. Radiation is only observed
>to transfer heat from hot to cold. That tends to equalize temperatures,
>reducing thermal gradients, not generating them.

Increasing impedance to outgoing radiation increases the lapse rate.

>Otherwise, you could simply set up a radiation field which generates a
>thermal gradient, then run a heat engine off the hot and cold sides,
>violating conservation of energy.

If suitable choice of materiels existed, one can huld a heat engine to
run within the layer of the Sun that does not significantly generate heat
from nuclear reactions but transports heat outward via radiation and
notably lacks convection.

Much of the Earth's troposphere has positive lapse rate, lack of
convection and for that matter to a significant extent even heat transport
(largely horizontally). Of course, mostly intermittently. The
hypothetical heat engine would still work as long as the lapse rate
ramained above zero.

>> Suppose the atmosphere completely lacked convexction and advection,
>> was transparent to solar radiation but had GHGs.
>>
>> Solar radiation comes in and heats the surface. The surface radiates
>> longer wavelength radiation. The longer wavelength radiation from the
>> surface gets absorbed and re-radiated many times before it gets out of
>> the atmosphere.
>
>Another way of looking at that is that from the surface up, each
>successive layer radiates to the layer immediately above via the Stephan
>Boltzman T^4 relationship between emitter and receiver. The downward
>"reradiation" is basically a virtual effect, because it can never transfer
>energy from cold to hot.

The downward radiation is indeed less than the upward radiation - it
merely resists the upward by a net effect short of 100%.

> The upper layer absorbs the photon, converts it
>to heat, then repeats the process to the next layer up, and so on.

That part is true.

>When you integrate the layers over some vertical distance, you have the
>transfer function from the surface to that point. All energy going into
>the system must either emerge from the top, or remain as sensible heat
>somewhere in the system, subject to convection upward whenever it becomes
>warmer then the air immediately above it. Energy can't be "trapped".

However, increase of GHGs increases the number of "hops/"steps"/"layers"
for the outgoing radiation, and increases "impedance" to outgoing
radiation. The surface remains on the whole cooled by radiation if GHGs
increase - but to a lesser extent.

>At some level, the air will be at 255K, and that altitude/pressure
>determines the surface temperature via the lapse rate(s). At least that's
>the way it looks to me.
>
>I think the radiation models are getting all wrapped around the axle
>because they attempt to account for "downward radiation" that can't
>actually have any physical effect. Cold objects simply can't transfer heat
>to hot objects. Entropy must increase.
>
>> There needs to be a temperature gradient in order to achieve heat
>> transport, even in such a "radiation layer".
>
>I would expect that gradient to be set by the adiabatic lapse rate due to
>the pressure variation with altitude.

The fact that Earth's atmosphere has any vertical motion or vertical
component in semi-horizontal motion of the troposphere causes the top of
the troposphere to be cooler than the bottom. See my prior posting(s)
about what happens in the troposphere over the intertropical convergence
zone (ITCZ), which includes a level range of the atmosphere that is
stratosphere over most of the world outside the tropics.

>>The Sun actually has such a layer outside the core where heat transport
>>is by radiation absorbed and re-radiated many times, rather than by
>>convection. There is a temperature gradient in order for heat transport
>>to be upward. Any given parcel of gas radiates a little more upward than
>>it receives from above, and receives a little more from below than it
>>radiates downward.
>
>To me, that looks more complicated than it needs to be. There's hot
>gas, heated by conduction from beneath, radiating to space. Unless, of
>course, it's plasma, in which case it doesn't really apply to Earth.

Heat transport in the "radiation layer" (or is it the "radiative
layer"?) in the Sun outside the "core" (where nuclear reactions generate
heat) does not depend on whether the material is "non-plasma gas" or
"plasma" - except where one has "adiabatic lapse rate" less than what is
present there but the other form of vaporous matter is what is there.
Meanwhile, the Sun still gives us great appearance of having a major
internal layer accounting for close enough to all of its outward heat
transport from its nuclear reactions by radiation and lacking convection
and with lapse rate in the direction of hotter towards where the heat is
coming from.

>>>The lapse rate is set by gas laws. Convection occurs because warm air
>>>is less dense than cold air, so it rises, expands, and adiabatically
>>>cools, still maintaining a higher temperature than its surroundings. It
>>>continues up until it reaches an altitude where the air around it is
>>>slightly warmer (the lapse rate changes) than its adiabatic temperature,
>>>where it releases its excess energy and stops, moving the lapse rate
>>>toward adiabatic.
>>
>> Except most of the atmosphere has lapse rate less than adiabatic due
>> to:
>>
>> 1. Radiational cooling of the surface (some radiation from the surface
>> gets pretty far - ever read the sky with a non contact thermometer?).
>>
>> 2. Many areas have lower atmospheric air coming from somewhere else
>> cooler and/or upper atmospheric air coming from someplace else warmer.
>
>All the atmosphere doesn't need to be involved, just enough to maintain
>the observed cooling.
>
>>>If the air rises to its dewpoint temperature, WV condenses, releasing
>>>latent heat and giving the rising parcel a boost. Go out and watch a
>>>cumulus cloud and you can see the flat bottom at the condensation
>>>altitude, and the energetic billowing of the cloud upward from the
>>>latent heat release. The principle is scalable, that's why thunderstorms
>>>can billow up well into the stratosphere, yielding the "anvil" shape.
>>
>> The top of the anvil is the tropopause.
>
>I guess so, by definition, but sometimes they get pretty high:
>
>http://blogs.trb.com/news/weather/weblog/wgnweather/2008/07/
>highest_thunderstorm_tops.html

><begin excerpt>
>In the Chicago area, garden-variety summer thunderstorms develop to
>heights between 35,000-45,000 feet, but the tops of severe thunderstorms
>here can approach 60,000 feet and in extreme cases 70,000 feet. The top of
>the thunderstorm that produced the Plainfield tornado on Aug. 28, 1990,
>towered to 65,000 feet. The tallest thunderstorms on Earth have been
>documented in the tropics where tops have been measured to about 75,000
>feet, building more than 14 miles up into the atmosphere.
><end excerpt>

You are citing extremes of extratropical thunderstorms in a
world-notable-extreme-severe-thunderstorm region of one continent (a
single nation - USA - has about half the world's tornadoes), yet you
noted tropical extreme being a little greater than USA extreme.

>> Also, most cumulus clouds don't become thunderstorms but stop growing
>> with their tops in the lower half of the troposphere. There are also
>> plenty of clouds other than cumulus, much of them formed by air rising
>> gradually while moving mainly horizontally.
>
>Granted, not all clouds have to cool equally. They don't have to if
>enough are unusually effective.

Often I see lots of cumulus clouds numbering thousands within an area
having none of them getting past the 700 mb level. Enough times I see so
much of such and cloud presence convective in nature (with majority of sky
being clear) to 300-plus km from me in every direction and something like
..01% of the land in such a wider area has convective clouds (on a
clearer more-convective day) getting to/past the 500 mb level by 11 AM or
noon or so.

>> Sometimes the lapse rate is a close match to the adiabatic lapse rate
>> (the dry one at altitudes lacking clouds, and the wet one at altitudes
>> having them). More often it is less.
>
>But surface heating will generally tend to increase convection, won't it?

Yes, that will!

>>>>> > Convection becomes progressively less potent as air pressure and
>>>>> > thus density declines with height, and as the partial pressure of
>>>>> > water vapour declines with decreasing temperature as it climbs up
>>>>> > through the tropopause, so the amount of energy transferred as
>>>>> > latent heat falls away with height in the same sort of way.
>>>
>>>See above, then consider what happens when an airplane encounters a TS
>>>at 20000 feet. IR doesn't disassemble aircraft in flight. There's
>>>plenty of energy in convection, even at altitude.
>>
>> Yes, there are little spots where vertical convection causes
>> considerable release of energy. Most heat transfer throughout the
>> atmosphere is otherwise - advection and radiation, especially advection.
>
>How do we know that, other than Trenberth's precipitation assumption?

How about the "global circulation" in both atmosphere and ocean
currents? In part as evidenced in the atmosphere, how about a very large
majority of the extratropical atmosphere having stratosphere at altitudes
and pressure levels where the tropics mostly have troposphere?

>>>Now why did you try to hide what I was responding to? You should know
>>>that won't work.
>>>
>>><unsnip>
>>>
>>>>> At night, convection stops, but cooling is not required at night.
>>>>> Convection kicks in during the day, when cooling is needed.
>>>>>
>>>>> I don't see how radiative cooling is even necessary below the cloud
>>>>> tops, since there's plenty of cooling capacity from convection.
>>>>
>>>> And there's solar energy availalbe to fuel it.
>>>
>>><end unsnip>
>>>>
>>>>> Exactly. It's a heat engine, with water as the working fluid. It
>>>>> cools the surface by using solar energy to convect latent heat to the
>>>>> cloud tops, from which it radiates as a black body to deep space.
>>>>>  Cloud shadows are a strong, easily observable negative
>>>>> temperature feedback, since they cut off surface heating as the
>>>>> clouds develop.
>>>>>
>>>>> >> Once the energy reaches the tropopause, as you imply, it's a
>>>>> >> pretty straight shot to 3K deep space, since there's not much
>>>>> >> atmosphere left to absorb IR.
>>>>
>>>> 25% of the mass of the atmosphere lies above the tropopause, and 25%
>>>> of the CO2. There's very little water vapour in the stratosphere - at
>>>> -55C any water around is ice.
>>>
>>>You need to keep your stories straight:
>>>
>>>Up thread, on: Wed, 26 Nov 2008 07:53:11 -0800 (PST)
>>>
>>>You said:
>>>"Sure. Most of the mass of the atmosphere - about 90% - is below the
>>>tropopause. But the stratosphere stretches out quite a long way."
>>>
>>>Do you always adjust the facts to match your argument? How do you expect
>>>to retain any credibility?
>>
>> Looks like he did do a bit of research or learning on that matter
>> recently - although in parts of the world (the tropics) the tropopause
>> is indeed over almost 90% of the atmosphere.
>
>Doesn't most of the surface cooling occur in the tropics?
>
>> Elsewhere the tropopause
>> is lower. In the "middle latitudes" the tropopause is indeed close to
>> the 250 mb level on average, though varying.
>
>How much surface cooling occurs in the mid-latitudes?
>
>> Water vapor is mostly in the troposphere
>
>Wouldn't that be mostly in the lower troposphere?

<I snip from here>

- Don Klipstein (don(a)misty.com)
From: Bill Ward on 15 Dec 2008 02:25
On Mon, 15 Dec 2008 03:49:54 +0000, Don Klipstein wrote:

> In article <pan.2008.12.02.09.04.49.526817(a)REMOVETHISix.netcom.com>, Bill
> Ward wrote:
>>On Tue, 02 Dec 2008 05:55:11 +0000, Don Klipstein wrote:
>>
>>> In <pan.2008.11.26.21.17.23.310423(a)REMOVETHISix.netcom.com>, Bill Ward
>>> 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:
>>>>>>
>>>>>> >> You should note that the infra-red spectra of both carbon dioxide
>>>>>> >> and water vapour absorb are line spectra, and the lines aren't
>>>>>> >> all that wide (though this does depend on atmopsheric pressure
>>>>>> >> and temperature - search on "pressure broadening") and they don't
>>>>>> >> overlap to any great extent, which allows both gases to make
>>>>>> >> independent contributions to the greenhouse effect.
>>>>>>
>>>>>>        Sloman resumes the AGW discussion
>>>>>> of spectra, with no numbers showing flux rates.  
>>>>>>  Water vapor has some pretty wide bands, CO2 much more
>>>>>> narrow.
>>>>>
>>>>> In the near infra-red, which is the region of most interest for
>>>>> global warming, both carbon dioxide and water show line spectra. Both
>>>>> are triatomic molecules which means that they have symmetric and
>>>>> asymmetric stretches and a bending mode. Each of the vibrational
>>>>> lines shows rotational fine structure. The individual rotational
>>>>> lines are quite narrow (to an extent that depends on pressure
>>>>> broadening).
>>>>>
>>>>> Here's a high resolution study of the water vapour spectrum
>>>>>
>>>>> http://www.usu.edu/alo/lidarinfo/spie%204484.pdf
>>>>>
>>>>> both sets of spectra look something like a picket fence at the
>>>>> resolution you need to model the greenhouse effect.
>>>>>
>>>>>> >> There's also the point that the vapour pressure of water in the
>>>>>> >> stratosphere is pretty low, because the stratosphere is cold, and
>>>>>> >> carbon dioxide does more of the greenhouse work up there than it
>>>>>> >> does below the tropopause.
>>>>>>
>>>>>>        Water has a very low boiling
>>>>>> point in the stratosphere because the pressure is low, does that
>>>>>> make the vapor pressure high or low?
>>>>>
>>>>> That's irrelevant - the temperature of the stratosphere is so low
>>>>> (-55C) that any water vapour around freezes to ice particles and the
>>>>> residual water vapour pressure is very low.
>>>>>
>>>>>>        The stratosphere is cold, so the
>>>>>> net energy transfer from the surface to the stratosphere is upward,
>>>>>> and the energy transfer to space is great.
>>>>>>
>>>>>>        AGW talkers completely leave out
>>>>>> much of the physics, gossip about spectra sounds mystical to the
>>>>>> greenhorn greenie, real physicists talk about energy transfer in
>>>>>> flux quantities per unit of time.
>>>>>>
>>>>>>        The amount of CO2 in the
>>>>>> stratosphere is minute, because the stratosphere has a pressure of
>>>>>> less than one pound per square inch, and not much mass.
>>>>>
>>>>> Sure. Most of the mass of the atmosphere - about 90% - is below the
>>>>> tropopause. But the stratosphere stretches out quite a long way.
>>>>>
>>>>>>        Frankly, if the lower troposphere
>>>>>> doesn't provide most of any GHG effect, then how can the lower
>>>>>> pressure, colder, less dense with less mass layers above have as
>>>>>> much of an effect?
>>>>>
>>>>> This is correct - the air temperature declines as you go up through
>>>>> the troposphere whch is to say that you've got a temperature gradient
>>>>> through an insulating blanket, and stabilises once you hit the bottom
>>>>> of the stratosphere at the tropopause, which is to say that the
>>>>> stratosphere isn't functioning as an insulator.
>>>>>
>>>>> Note that the top of the troposphere is also pretty cold and thus
>>>>> nearly as low on water vapour.
>>>>>
>>>>>>        Rather than try to put physics to
>>>>>> such vague gossip as spectra bands, it would be better to start from
>>>>>> scratch, study the temperature, pressure, mass, specific heat and
>>>>>> energy content of a quantity of the atmosphere at each level, and
>>>>>> the capability to radiate or absorb Infra- red.
>>>>>
>>>>> That's what the climatologists models do, but they also have to keep
>>>>> track of heat flux carried by mass-transfer - both by simple
>>>>> convection and the heat that is moved upwards as water vapour to be
>>>>> released when the water vapour condenses to liquid water (rain and
>>>>> clouds) and ice (ice clouds and hail).
>>>>>
>>>>>>        CO2 plays such a small part in
>>>>>> atmospheric physics, it could be totally ignored without changing
>>>>>> the outcome a measurable amount.
>>>>>
>>>>> Wrong.
>>>>>
>>>>>>        Water vapor concentration can
>>>>>> increase and decrease many times the total concentration of CO2 and
>>>>>> it doesn't change the temperature much, in fact, dry air can get
>>>>>> hotter faster or colder faster, than moist air.
>>>>>
>>>>> So what?
>>>>>
>>>>>>        More moisture means more IR
>>>>>> absorption, but moist air moderates temperature changes.  
>>>>>>  CO2 has no phase change at atmospheric temperature and
>>>>>> pressure, and has a very low activity level compared to water and
>>>>>> water vapor and ice.
>>>>>
>>>>> But is is very effective in "pressure broadening" the water vapour
>>>>> rotational lines - much more so than oxygen and nitrogen, which are
>>>>> non-polar molecules and don't stick to water during collisons for
>>>>> nearly as long as CO2.
>>>>>
>>>>>>        At the temperatures at higher
>>>>>> altitudes, IR radiation is sparse,
>>>>>
>>>>> Nonsense, the Earth - or rather the tropopause - is a black body
>>>>> radiator in the near infra-red and the radiation flux out to the rest
>>>>> of the universe only depends on the temperature through the
>>>>> tropopause.
>>>>
>>>>Maybe we're getting somewhere now. How do you account for the fact the
>>>>tropospheric lapse rate stays close to adiabatic?
>>>
>>> Average lapse rate in the troposphere is close to the "wet adiabatic"
>>> figure while half the tropopause lacks clouds at any altitude.
>>
>>Do you think that the "wet adiabatic" environmental lapse rate is related
>>to latent heat, or is it simply less than the dry adiabatic lapse rate
>>because it's not at equilibrium?
>
> It is less due to latent heat.
>
> The "1 size fits all figures" that I have heard are 3.5 degrees F per
> 1,000 feet for the wet one and 5.4 degrees F per 1,000 feet for the dry
> one.
>
>>>> Is it primarily by radiative transfer, or convection? It seems to
>>>> me
>>>>it must be convective, simply because warm, wet air is less dense than
>>>>cold, dry air, and quickly rises to maintain the lapse rate.
>>>
>>> Much of the time the answer is a significant factor other than
>>> radiation and vertical convection. Much of the "global convection"
>>> involves air movement within a degree of horizontal, and often forming
>>> clouds when moving upwards. Sometimes the lapse rate there is between
>>> the "dry adiabatic" and the "wet adiabatic" rates and the clouds have
>>> billowy cumuliform tops or are cumuliform throughout. Sometimes "warm
>>> advection" occurs more at cloud-top level than at cloud-base level
>>> (from the windspeed being greater higher up in the troposphere),
>>> causing the clouds to be stratiform.
>>
>>OK, that all sounds plausible, but I'm not sure how much effect the
>>horizontal component would have, other than the obvious mixing.
>
> The horizontal component involves atmospheric heat transfer from the
> tropics to the poles. It is very significant. It leads to frontal
> inversions, which cover significant area ahead of warm fronts (including
> areas where the warm fronts fail to reach at the surface). It leads to
> existence of stratosphere at middle and upper latitudes at pressure levels
> below that of the tropical tropopause.
>
>>>>IR radiated from the surface would be quickly absorbed by WV, clouds,
>>>>CO2, and other GHGs, and at 500W/m^2 would be overwhelmed by the 10's
>>>>of kW/m^2 available from convection of latent heat.
>>>
>>> Half the Earth's surface has no clouds overhead at any altitude.
>>
>>Surely you mean "at any given time". Or are there really regions
>>comprising half the Earth's surface that have never had a cloud in the
>>sky?
>
> I did mean "at any given time", and "those given times" in "those
> given locations" account for half the world lacking clouds at any
> altitude.

OK, I'll buy that as an average. But I'll bet the tropics are far more
likely to be cloudy than the polar regions, and that's where most of the
cooling occurs.

>>> The surface manages to radiate *somewhat* to outer space at night when
>>> the air overhead is clear - otherwise there would be no such thing as
>>> nighttime frost when air 2 meters above the surface is at +2 degrees C
>>> (a fairly common situation). Some of the outgoing radiation can easily
>>> be absorbed and reradiated a couple or a few times by GHGs, but net of
>>> that is upward (and upward net is reduced by increase of GHGs).
>>
>>OK, no argument with that. I look at it as the surface radiating to a
>>target warmer than 3K space, but it's the same math.
>>>
>>>>At night, convection stops, but cooling is not required at night.
>>>>Convection kicks in during the day, when cooling is needed.
>>>
>>> Cooling still occurs at night by radiation. 5 AM temperature has a
>>> great rate of being less than 10 PM temperature. Upper level of
>>> radiation by atmosphere at night has half of its radiation to outer
>>> space. That heat comes from radiation from surface - even if absorbed
>>> and reradiated a couple times along the way.
>>
>>Agreed. At night the flux is always outward.
>>
>>> The "upper radiation level" also varies greatly with wavelength.
>>
>>Do you mean the "effective radiating altitude", which is calculated, or
>>some sort of integrated spectrum involving all the photons reaching a
>>surface outside the atmosphere, like a satellite imager? Neither I, nor
>>apparently Google, is familiar withe the term "upper radiation level".
>
> Looks like I did not choose wrds well - it should have been "effective
> radiating altitude".
>
> Keep in mind that the "effective radiating altitude" is very fuzzy,
> since some wavelengths radiated by the surface have good atmospheric
> transparency (and a fairly clear shot to space) as long as there are no
> clouds, others have low chance of reaching the 500 mb level without being
> absorbed, and some are in-between - with absorption and reradiation
> varying directly with concentration of GHGs.

That's my point. It's not well enough known to claim 1.5W/m^2 is going to
make any difference at all. All it takes is a minor negative
feedback loop to correct for that small an effect.

>
>>>>I don't see how radiative cooling is even necessary below the cloud
>>>>tops, since there's plenty of cooling capacity from convection.
>>>
>>> When frost or dew forms on the ground and on cars and trucks, the
>>> heat
>>> loss has a very impressive rate of by being by radiation.
>>
>>True, but radiation is peanuts compared to the available cooling
>>capacity of latent heat during the day. If the surface radiation were
>>blocked, convection could easily make it up.
>
> What about on days when there is no convection past the 750 mb or so
> level for even a minute? (I see plenty of those even with sky
> half-clear and cumulus clouds present.) What about in Arctic and
> upper-midlatitude areas where change in radiation balance during the 18
> or whatever hours per day with little convection has a significicant
> effect on snow/ice cover, and that affects how much solar radiation the
> surface absorbs?

It's the total transferred power that counts. It doesn't take much latent
heat convection to make up for a lot of radiation. The place to look for
changes is where the cooling is greatest, not places which are already
being warmed by the tropics.

>>>>Once the energy reaches the tropopause, as you imply, it's a pretty
>>>>straight shot to 3K deep space, since there's not much atmosphere left
>>>>to absorb IR.
>>>>
>>>>Perhaps it's easier to see if you look at the lapse rate as bounded at
>>>>the top by the effective radiating temperature, and consider the
>>>>surface temperatures as derived from that and the adiabatic lapse
>>>>rate.
>>>
>>> That gets complicated by half the troposphere having lack of clouds
>>> at
>>> any altitude, and there are separate adiabatic lapse rates for clear
>>> air and clouded air. The global atmospheric average is close to the
>>> "wet" one, leaving upward mobility of lapse rate in the clear half of
>>> the world and in clear layers of the atmosphere in the clouded half of
>>> the world.
>>
>>At any given point, the applicable lapse rate should be obvious,
>>depending on whether cloud is present. I'm not convinced the lower
>>"average" environmental lapse rate has much to do with latent heat. It
>>might just be off-equilibrium due to transport lags or the like.
>
> It just happens to be that the "average lapse rate below the
> tropopause" is close to the wet adiabatic one. Close to the equator,
> it is more than coincidental - global circulation (from atmosphere
> below_tropical_tropopause_pressure_level as-a-whole) being warmer
> towards the equator and cooler towards the poles has air in the
> intertropical convergence zone rising. That largely establishes the
> lapse rate in the ITCZ as being close to the wet adiabatic one from
> the levels of the bases of the deep tall tropical convective clouds to
> the tropical tropopauuse. Below that cloud base level where those
> clouds form, the lapse rate is close to the dry adiabatic one at hot
> times of the day, and less at other times.
>
> Although it sounds like global circulation merely forces upward air
> movement in the ITCZ and that should cause clouds other than the billowy
> cumulus of natural convection, those show up anyway (along with a lot of
> clear air). Surface temperature in the ITCZ is not uniform. For one
> thing, some parts of the ITCZ have daylight and others have night. Also,
> ocean currents cool the ITCZ unevenly. So, upward air movement in the
> ITCZ occurs in hotspots where natural convection is sufficient to
> account for the upward global atmospheric circulation in the ITCZ - and
> the clouds there are billowy thunderheads, with many having anvil tops.

I've often seen precipitation falling out of the anvil, many times never
reaching the ground. The energy in a thunderstorm is staggering, and
seems far more than IR could ever provide. Most of that energy had
to have come from the surface, and there's really no way back down. It
seems to me it has to radiate to space.

Thermals are what got me started on this issue. I asked myself just how
much IR it would take to lift a sailplane at a thousand feet/minute.
I immediately had doubts that IR is significant. The energy is clearly
mechanical energy of convection, and the cloud (if any)sitting on top of
the thermal has to represent an order of magnitude more energy from
latent heat.

Thermals may not be all that common on the average, but when they do
occur, they must carry orders of magnitude more energy than IR.

When I look (longingly) at pictures of tropical islands, I see very
familiar looking clouds. I have to assume the dynamics are similar,
and that they are common in the tropics. So I need a lot of convincing
evidence before I'll believe their heat transfer ability is somehow
comparable to an already cold polar surface or similar situation. All it
would take is a slight modulation of humidity or lapse rate to have large
effects on the power transmitted, far greater than the 1.5W/m^2 CO2
forcing assumed in the climate models.

> Do keep in mind that there is global atmospheric circulation at
> altitudes and pressure levels that are troposphere in the tropics and
> stratosphere elsewhere. Air rising through the ITCZ to close to the 100
> mb level does not all go down there but some descends elsewhere
> poleward. And a lot of that moves poleward at altitudes where the is
> little hope of convection to such level from the surface, due to surface
> being cooler than in the ITCZ. At some of these
> extratropical-stratospheric altitudes and pressure levels, atmosphere is
> even usually warmer than it is over the ITCZ because over the ITCZ it is
> so cold (from cooling by uplifting) that local radiation balance warms
> the air moving largely horizontally at/near the tropical tropopause
> level. It cools by radiation in order to descend elsewhere, with much
> of that done during the descent - especially in the polar regions.

That seems reasonable, but I don't see how it really affects the tropical
convection cells. That's how the energy got up there in the first place.

>>Thanks for your clarifications. I appreciate rational discussion.
>>
>>> <I snip from that next triple-quote symbol due to lesser relevance to
>>> argument in this little region of the massive thread>
>>>
>>> - Don Klipstein (don(a)misty.com)
>
> - Don Klipstein (don(a)misty.com)

From: Bill Ward on 15 Dec 2008 17:39
On Mon, 15 Dec 2008 05:58:42 +0000, Don Klipstein wrote:

> In article <pan.2008.12.08.07.58.38.490710(a)REMOVETHISix.netcom.com>, Bill
> Ward wrote:
>>On Mon, 08 Dec 2008 03:35:34 +0000, Don Klipstein wrote:
>>
>>> In article <pan.2008.11.27.19.50.55.98497(a)REMOVETHISix.netcom.com>,
>>> Bill Ward 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:
>>>>> <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 trophosphere 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
>>>>> can do anything.
>>>>
>>>>Where did I say the radiation all comes from a thin layer? You must be
>>>>misinterpreting the concept of effective radiating altitude.
>>>>
>>>>
>>>>>> >> IR radiated from the surface would be quickly absorbed by WV,
>>>>>> >> clouds, CO2, and other GHGs, and at 500W/m^2 would be overwhelmed
>>>>>> >> by the 10's of kW/m^2 available from convection of latent heat.
>>>>>>
>>>>>> > Clouds scatter infra-red radiation rather than absorbing it. as do
>>>>>> > the greenhouse gases, but that's enough to sustain a thermal
>>>>>> > gradient.
>>>>>>
>>>>>> Surely you're not proposing the lapse rate is sustained by outgoing
>>>>>> IR. All the sources I've seen say the troposphere is due to
>>>>>> convection, not radiation.  Can you find one to the contrary.
>>>>>
>>>>> Don't have to. Convection and transport as latent heat both decrease
>>>>> rapidly as you move up through the troposphere, and radiation
>>>>> progressively takes over, becoming responsible for 100% of the heat
>>>>> transfer by the time you get to the tropopause. This is clearly
>>>>> implied by what I wrote earlier (which is why I've not snipped it).
>>>>
>>>>So you don't really understand convection or radiation. If you did,
>>>>you might see that radiation could not generate a "thermal gradient".
>>>>Radiation tends to equalize temperatures, you know. It's described by
>>>>all that second law stuff you must have somehow skipped over.
>>>
>>> Radiation alone can generate a thermal gradient.
>>
>>That seems to me to be against the second law. Radiation is only
>>observed to transfer heat from hot to cold. That tends to equalize
>>temperatures, reducing thermal gradients, not generating them.
>
> Increasing impedance to outgoing radiation increases the lapse rate.

That may be, but the radiation is still tending to equalize the thermal
gradient by transferring heat from the lower, warmer levels to the higher,
colder levels. Gravity generated the temperature gradient, not radiation.

>>Otherwise, you could simply set up a radiation field which generates a
>>thermal gradient, then run a heat engine off the hot and cold sides,
>>violating conservation of energy.
>
> If suitable choice of materiels existed, one can huld a heat engine to
> run within the layer of the Sun that does not significantly generate
> heat from nuclear reactions but transports heat outward via radiation
> and notably lacks convection.

Sure. You've got a hot side and a cold side. Radiation is trying to
equalize them, so you'd want to limit the radiation, as it bypasses
otherwise usable energy around the heat engine. Radiation always
transfers energy in the direction that maximizes entropy.

> Much of the Earth's troposphere has positive lapse rate, lack of
> convection and for that matter to a significant extent even heat
> transport (largely horizontally). Of course, mostly intermittently. The
> hypothetical heat engine would still work as long as the lapse rate
> ramained above zero.
>
>>> Suppose the atmosphere completely lacked convexction and advection,
>>> was transparent to solar radiation but had GHGs.
>>>
>>> Solar radiation comes in and heats the surface. The surface
>>> radiates
>>> longer wavelength radiation. The longer wavelength radiation from the
>>> surface gets absorbed and re-radiated many times before it gets out of
>>> the atmosphere.
>>
>>Another way of looking at that is that from the surface up, each
>>successive layer radiates to the layer immediately above via the Stephan
>>Boltzman T^4 relationship between emitter and receiver. The downward
>>"reradiation" is basically a virtual effect, because it can never
>>transfer energy from cold to hot.
>
> The downward radiation is indeed less than the upward radiation - it
> merely resists the upward by a net effect short of 100%.

Looking down, you don't really care what heated the radiating layer, it's
the temperature that determines the upward radiation. What goes on below
the radiating layer is between it and the lower level, literally.

>> The upper layer absorbs the photon, converts it
>>to heat, then repeats the process to the next layer up, and so on.
>
> That part is true.
>
>>When you integrate the layers over some vertical distance, you have the
>>transfer function from the surface to that point. All energy going into
>>the system must either emerge from the top, or remain as sensible heat
>>somewhere in the system, subject to convection upward whenever it
>>becomes warmer then the air immediately above it. Energy can't be
>>"trapped".
>
> However, increase of GHGs increases the number of
> "hops/"steps"/"layers"
> for the outgoing radiation, and increases "impedance" to outgoing
> radiation. The surface remains on the whole cooled by radiation if GHGs
> increase - but to a lesser extent.

I don't buy that. I think the upward radiation is strictly due to the
temperature of the radiating layer, and any other information is lost when
the IR became sensible heat.
>
>>At some level, the air will be at 255K, and that altitude/pressure
>>determines the surface temperature via the lapse rate(s). At least
>>that's the way it looks to me.
>>
>>I think the radiation models are getting all wrapped around the axle
>>because they attempt to account for "downward radiation" that can't
>>actually have any physical effect. Cold objects simply can't transfer
>>heat to hot objects. Entropy must increase.
>>
>>> There needs to be a temperature gradient in order to achieve heat
>>> transport, even in such a "radiation layer".
>>
>>I would expect that gradient to be set by the adiabatic lapse rate due
>>to the pressure variation with altitude.
>
> The fact that Earth's atmosphere has any vertical motion or vertical
> component in semi-horizontal motion of the troposphere causes the top of
> the troposphere to be cooler than the bottom. See my prior posting(s)
> about what happens in the troposphere over the intertropical convergence
> zone (ITCZ), which includes a level range of the atmosphere that is
> stratosphere over most of the world outside the tropics.

I'll stipulate that there is often a significant horizontal component
(advection) to the heat-caused motion of the air. But that horizontal
motion must be driven by density differences and gravity, which requires
vertical motion. That vertical component must lift heat. The horizontal
component determines where that heat is eventually radiated to space.

>>>The Sun actually has such a layer outside the core where heat transport
>>>is by radiation absorbed and re-radiated many times, rather than by
>>>convection. There is a temperature gradient in order for heat
>>>transport to be upward. Any given parcel of gas radiates a little more
>>>upward than it receives from above, and receives a little more from
>>>below than it radiates downward.
>>
>>To me, that looks more complicated than it needs to be. There's hot
>>gas, heated by conduction from beneath, radiating to space. Unless, of
>>course, it's plasma, in which case it doesn't really apply to Earth.
>
> Heat transport in the "radiation layer" (or is it the "radiative
> layer"?) in the Sun outside the "core" (where nuclear reactions generate
> heat) does not depend on whether the material is "non-plasma gas" or
> "plasma" - except where one has "adiabatic lapse rate" less than what is
> present there but the other form of vaporous matter is what is there.

Isn't plasma more likely to act as a blackbody than cold gas?

> Meanwhile, the Sun still gives us great appearance of having a major
> internal layer accounting for close enough to all of its outward heat
> transport from its nuclear reactions by radiation and lacking convection
> and with lapse rate in the direction of hotter towards where the heat is
> coming from.

My hunch is it's a lot more than 240W/m^2. I'm certainly not disputing
the radiation laws, I just don't think the Sun is a convincing proxy for
Earth.

>>>>The lapse rate is set by gas laws. Convection occurs because warm air
>>>>is less dense than cold air, so it rises, expands, and adiabatically
>>>>cools, still maintaining a higher temperature than its surroundings.
>>>>It continues up until it reaches an altitude where the air around it
>>>>is slightly warmer (the lapse rate changes) than its adiabatic
>>>>temperature, where it releases its excess energy and stops, moving the
>>>>lapse rate toward adiabatic.
>>>
>>> Except most of the atmosphere has lapse rate less than adiabatic due
>>> to:
>>>
>>> 1. Radiational cooling of the surface (some radiation from the
>>> surface gets pretty far - ever read the sky with a non contact
>>> thermometer?).
>>>
>>> 2. Many areas have lower atmospheric air coming from somewhere else
>>> cooler and/or upper atmospheric air coming from someplace else warmer.
>>
>>All the atmosphere doesn't need to be involved, just enough to maintain
>>the observed cooling.
>>
>>>>If the air rises to its dewpoint temperature, WV condenses, releasing
>>>>latent heat and giving the rising parcel a boost. Go out and watch a
>>>>cumulus cloud and you can see the flat bottom at the condensation
>>>>altitude, and the energetic billowing of the cloud upward from the
>>>>latent heat release. The principle is scalable, that's why
>>>>thunderstorms can billow up well into the stratosphere, yielding the
>>>>"anvil" shape.
>>>
>>> The top of the anvil is the tropopause.
>>
>>I guess so, by definition, but sometimes they get pretty high:
>>
>>http://blogs.trb.com/news/weather/weblog/wgnweather/2008/07/
>>highest_thunderstorm_tops.html
>
>><begin excerpt>
>>In the Chicago area, garden-variety summer thunderstorms develop to
>>heights between 35,000-45,000 feet, but the tops of severe thunderstorms
>>here can approach 60,000 feet and in extreme cases 70,000 feet. The top
>>of the thunderstorm that produced the Plainfield tornado on Aug. 28,
>>1990, towered to 65,000 feet. The tallest thunderstorms on Earth have
>>been documented in the tropics where tops have been measured to about
>>75,000 feet, building more than 14 miles up into the atmosphere. <end
>>excerpt>
>
> You are citing extremes of extratropical thunderstorms in a
> world-notable-extreme-severe-thunderstorm region of one continent (a
> single nation - USA - has about half the world's tornadoes), yet you
> noted tropical extreme being a little greater than USA extreme.

Just an example of "can billow". Not necessarily typical.

>>> Also, most cumulus clouds don't become thunderstorms but stop
>>> growing
>>> with their tops in the lower half of the troposphere. There are also
>>> plenty of clouds other than cumulus, much of them formed by air rising
>>> gradually while moving mainly horizontally.
>>
>>Granted, not all clouds have to cool equally. They don't have to if
>>enough are unusually effective.
>
> Often I see lots of cumulus clouds numbering thousands within an area
> having none of them getting past the 700 mb level. Enough times I see
> so much of such and cloud presence convective in nature (with majority
> of sky being clear) to 300-plus km from me in every direction and
> something like .01% of the land in such a wider area has convective
> clouds (on a clearer more-convective day) getting to/past the 500 mb
> level by 11 AM or noon or so.

Not all the Earth's surface is going to be involved at any given time.
Even so, the 700mb layer is almost a third of the way out. That's not
chopped liver.

>>> Sometimes the lapse rate is a close match to the adiabatic lapse
>>> rate
>>> (the dry one at altitudes lacking clouds, and the wet one at altitudes
>>> having them). More often it is less.
>>
>>But surface heating will generally tend to increase convection, won't
>>it?
>
> Yes, that will!

So the surface cools faster when it gets hot. That's negative feedback.

>>>>>> > Convection becomes progressively less potent as air pressure and
>>>>>> > thus density declines with height, and as the partial pressure of
>>>>>> > water vapour declines with decreasing temperature as it climbs up
>>>>>> > through the tropopause, so the amount of energy transferred as
>>>>>> > latent heat falls away with height in the same sort of way.
>>>>
>>>>See above, then consider what happens when an airplane encounters a TS
>>>>at 20000 feet. IR doesn't disassemble aircraft in flight. There's
>>>>plenty of energy in convection, even at altitude.
>>>
>>> Yes, there are little spots where vertical convection causes
>>> considerable release of energy. Most heat transfer throughout the
>>> atmosphere is otherwise - advection and radiation, especially
>>> advection.
>>
>>How do we know that, other than Trenberth's precipitation assumption?
>
> How about the "global circulation" in both atmosphere and ocean
> currents? In part as evidenced in the atmosphere, how about a very
> large majority of the extratropical atmosphere having stratosphere at
> altitudes and pressure levels where the tropics mostly have troposphere?

I was referring to the low fraction of cooling Trenberth attributed to
latent heat. He simply used the estimated global precipitation, which is
the absolute lower limit. It assumes that all precipitation falls to the
ground and is measured.

>>>>Now why did you try to hide what I was responding to? You should know
>>>>that won't work.
>>>>
>>>><unsnip>
>>>>
>>>>>> At night, convection stops, but cooling is not required at night.
>>>>>> Convection kicks in during the day, when cooling is needed.
>>>>>>
>>>>>> I don't see how radiative cooling is even necessary below the cloud
>>>>>> tops, since there's plenty of cooling capacity from convection.
>>>>>
>>>>> And there's solar energy availalbe to fuel it.
>>>>
>>>><end unsnip>
>>>>>
>>>>>> Exactly. It's a heat engine, with water as the working fluid. It
>>>>>> cools the surface by using solar energy to convect latent heat to
>>>>>> the cloud tops, from which it radiates as a black body to deep
>>>>>> space.  Cloud shadows are a strong, easily observable
>>>>>> negative temperature feedback, since they cut off surface heating
>>>>>> as the clouds develop.
>>>>>>
>>>>>> >> Once the energy reaches the tropopause, as you imply, it's a
>>>>>> >> pretty straight shot to 3K deep space, since there's not much
>>>>>> >> atmosphere left to absorb IR.
>>>>>
>>>>> 25% of the mass of the atmosphere lies above the tropopause, and 25%
>>>>> of the CO2. There's very little water vapour in the stratosphere -
>>>>> at -55C any water around is ice.
>>>>
>>>>You need to keep your stories straight:
>>>>
>>>>Up thread, on: Wed, 26 Nov 2008 07:53:11 -0800 (PST)
>>>>
>>>>You said:
>>>>"Sure. Most of the mass of the atmosphere - about 90% - is below the
>>>>tropopause. But the stratosphere stretches out quite a long way."
>>>>
>>>>Do you always adjust the facts to match your argument? How do you
>>>>expect to retain any credibility?
>>>
>>> Looks like he did do a bit of research or learning on that matter
>>> recently - although in parts of the world (the tropics) the tropopause
>>> is indeed over almost 90% of the atmosphere.
>>
>>Doesn't most of the surface cooling occur in the tropics?
>>
>>> Elsewhere the tropopause
>>> is lower. In the "middle latitudes" the tropopause is indeed close to
>>> the 250 mb level on average, though varying.
>>
>>How much surface cooling occurs in the mid-latitudes?
>>
>>> Water vapor is mostly in the troposphere
>>
>>Wouldn't that be mostly in the lower troposphere?
>
> <I snip from here>
>
> - Don Klipstein (don(a)misty.com)

From: Don Klipstein on 15 Dec 2008 22:02
In article <ca0aj4dum4kav8292lloctj14jttpun9gu(a)4ax.com>, Whata Fool wrote:
>don(a)manx.misty.com (Don Klipstein) wrote:
>
>>In article <sfaqi41dau09mn1jdb9508t3f2t2hsj9ba(a)4ax.com>, Whata Fool wrote:
>>>Eeyore <rabbitsfriendsandrelations(a)hotmail.com> wrote:
>>>
>>>>bill.sloman(a)ieee.org wrote:
>>>>>
>>>>> You should note that the infra-red spectra of both carbon dioxide and
>>>>> water vapour absorb are line spectra, and the lines aren't all that
>>>>> wide (though this does depend on atmopsheric pressure and temperature
>>>>> - search on "pressure broadening") and they don't overlap to any great
>>>>> extent, which allows both gases to make independent contributions to
>>>>> the greenhouse effect.
>>>
>>> Sloman resumes the AGW discussion of spectra, with no numbers
>>>showing flux rates. Water vapor has some pretty wide bands, CO2
>>>much more narrow.
>>
>> Cite?
>
>
>http://www.globalwarmingart.com/images/7/7c/Atmospheric_Transmission.png
>
> These graphs show the spectra of GHGs without respect for the
>concentration of the gas, and without respect for the temperature
>of the source emitter.

I have seen that one elsewhere. The absorption spectra are those of
GHGs of the entire thickness of the atmosphere.

http://www.iitap.iastate.edu/gccourse/forcing/images/image7.gif
http://www.iitap.iastate.edu/gccourse/forcing/spectrum.html

http://en.wikipedia.org/wiki/File:Atmospheric_Transmission.png

> GreenHouse Gas theory science would be well served to have the
>availability of a graph that combines the all three quantity factors
>in absorption, concentration of GHG and temperature of source, maybe
>you can find one, I can't.
>
> So I have to estimate the absorption of each gas reduced by the
>relative ratio of concentration of the two gases, for the temperature
>of the source emitter.
>
> Below cloud level I get about 2 percent for CO2 and 97 percent
>for water vapor.

The cites above make me think that what I hear, namely 9-26% of
"greenhouse effect" is from CO2, is true.

> Above cloud level, I estimate about 50-50, but only about 10
>percent of the atmosphere mass is there.

Only in the tropics is the tropopause usually above close to 90% of the
atmosphere. For the world as a whole, the tropopause has more like 20-25%
of the atmosphere above it. Furthermore, in much of the portion of the
world having clouds, the highest cloud tops are well below the tropopause.

>> Also, CO2 has absorption at wavelengths where water vapor has little to
>>none, to an extent giving CO2 9-26% of total "greenhouse gas effect".
>
> I don't think so in effect for Earth, but agree at equal concentration.

The graphs noted above are for the concentration actually on average in
Earth's atmosphere.

>>>>> There's also the point that the vapour pressure of water in the
>>>>> stratosphere is pretty low, because the stratosphere is cold, and
>>>>> carbon dioxide does more of the greenhouse work up there than it does
>>>>> below the tropopause.
>>>
>>> Water has a very low boiling point in the stratosphere because
>>>the pressure is low, does that make the vapor pressure high or low?
>>
>> The water vapor pressure in the stratosphere is low due to low
>>temperature.
>
> Same at the poles in winter, but ice sublimes some at any
>temperature, apparently within the biosphere.

Ice only sublimes where it is below freezing. At the surface, water
vapor condenses directly to ice without being liquid water where the
surface experiences radiational cooling and where water vapor
concentration is less than the vapor pressure of water at the freezing
point of water.

>>> The stratosphere is cold, so the net energy transfer from the
>>>surface to the stratosphere is upward, and the energy transfer to space
>>>is great.
>>
>> Increased presence of greenhouse gases actually cools most of the
>>stratosphere. That would increase lapse rate - which would mean a
>>negative feedback mechanism.
>
> Feedback is obviously a flawed concept in GHG theory, humid
>days do not get as hot as dry days, etc.

Humid days have warmer nights than dry days. Also, I see dry days being
the ones achieving extremes of temperature in both directions. Hot dry
days get hotter than hot humid days because dryness favors greater
altitude range of lapse rate approaching or equaling the dry adiabatic
one - extreme heat of hot dry days is localized to surface and lower
troposphere, and dependent on weather paterns favoring local/regional
dry heat.
Or do you consider water vapor to not be a greenhouse gas after
all?

>> However, there are a few positive feedback mechanisms, including
>>surface albedo (increases heat reception from the Sun) - so lapse rate
>>increase instead raises the altitude of the tropopause. (Temperature
>>difference between surface and stratosphere has to increase by about 3.5
>>degrees F in areas of the globe having convection to raise the tropopause
>>by a mere 1,000 feet.)
>
> Since the temperature data used in calculating average temperature
>in AGW, the altitude of the tropopause seems to lose significance,

Huh? Explain that better?

>>> AGW talkers completely leave out much of the physics, gossip
>>>about spectra sounds mystical to the greenhorn greenie, real physicists
>>>talk about energy transfer in flux quantities per unit of time.
>>>
>>> The amount of CO2 in the stratosphere is minute, because the
>>>stratosphere has a pressure of less than one pound per square inch,
>>>and not much mass.
>>
>> More like 20% of the mass of Earth's atmosphere is in the stratosphere.
>>Even in the tropics where the tropopause is higher, the pressure at the
>>tropopause is about 1.4 PSI.
>
> I assume about one PSI for the region where there is little water,

And how do you support such claim for tropopause being that high over
dry areas? Or are you talking about some representation of the
stratosphere?

>but CO2 is also sparse is some parts of the stratosphere,

It ain't far from 380 ppmv or whatever it was at Mauna Loa a few years
ago. The stratosphere is within the "homosphere" - the portion of the
atmosphere where there is sufficient mixing to make it "essentially
homogenous" with exception for vater vapor and water particles.

>and the pressure differential in the atmosphere may provide refraction
>of the direction of the IR radiation causing as much as 70 percent of
>stratospheric IR radiation to be to space.

But sunlight from sun within 1 degree of the horizon is only bent by a
fraction of a degree - so I suspect you got a bad number somewhere.

>>> Frankly, if the lower troposphere doesn't provide most of any
>>>GHG effect, then how can the lower pressure, colder, less dense with
>>>less mass layers above have as much of an affect?
>>
>> The lower half of the troposphere does have significant GHG effect.
>>The lower troposphere has warmed a lot more since 1979 than the middle
>>troposphere has.
>
> I have lived there and have not noticed a warming, there is no
>way any year has been as hot as the early 1950s, although the average
>minimum temperatures have not been as low.

Please tell me where you live, where early 1950's was a hot time.
HadCRUT-3 and HadCRUT-3v say those were colder times worldwide, hardly
above the late-1940's dip. HadCRUT-3v is good enough for The Register in
their "A Tale of Two Thermometers" article!

>> (Remss.com provides among other things "lower troposphere" and "middle
>>troposphere" determinations of temperatuire trend. The "lower troposphere"
>>determination is from weighting of atmospheric thermal radiation readings
>>in a way to concentrate on the lowest 4 km, and that excludes areas where
>>the surface is at least 3 km above sea level. The "middle troposphere"
>>determination is done with weighting of atmospheric thermal radiation
>>readings weighted in a way to concentrate onto 4-7 km above sea level.)
>
> The local warming obviously can have an effect on some species,
>but citrus growers can't control temperature over a few acres, why
>do AGW proponents think the temperature of the atmosphere can be
>controlled?

I thought I answered that one before...

Citrus growers throwing out heat have most of their heat output
heating the portion of the world outside their farms.

> The high temperature is what really counts and the number of
>hours at or near maximum, the low daily temperature only has a very
>significant effect on biology where the temperature goes well below
>freezing more than a few days a year.

My experience is that species are limited much more by low temperature
extents rather than high temperature extents.
For one thing, consider the record high temperature for North Dakota
compared to the record high temperature for Texas.
Compare the record high temperature for Pennsylvania compared to the
record high temperature for Florida.
Check out what the alltime record high temperature for Key West, Florida
is. Find how little of USA has failed to get hotter.
Check out the record high temperature for the entire state of Hawaii.
Find how many USA "states" have alltime high lower than that of Hawaii -
ZERO! Find how many USA "states" have alltime record high temperature
higher than that of Hawaii - 48!

>>> Rather than try to put physics to such vague gossip as spectra
>>>bands, it would be better to start from scratch, study the temperature,
>>>pressure, mass, specific heat and energy content of a quantity of the
>>>atmosphere at each level, and the capability to radiate or absorb Infra-
>>>Red.
>>>
>>> CO2 plays such a small part in atmospheric physics, it could be
>>>totally ignored without changing the outcome a measurable amount.
>>
>> But anywhere from 9-26% of GHG effect via having absorption at
>>wavelengths where water vapor does not?
>
> I don't agree with those numbers in actual effect, and if my premise
>that the atmosphere would be warmer is correct, then added CO2 could only
>make it cooler. :-)

Do you mean warmer with less GHGs? If so, please see what I have posted
in other articles in response to you!

> The trend in the Arctic and other local regions may not be caused
>by increased CO2 at all.
>
>>> Water vapor concentration can increase and decrease many times
>>>the total concentration of CO2 and it doesn't change the temperature
>>>much, in fact, dry air can get hotter faster or colder faster, than
>>>moist air.
>>
>> Dry air heats at surface more easily since adiabatic lapse rate is at
>>the greater dry rate over a greater range of altitudes. Air also heats
>>more easily when the land under it lacks water to be evaporated (big heat
>>burden).
>> Dry air cools more easily since lack of water vapor means less latent
>>heat (realized if dew or frost or fog or foggy low clouds form) and dry
>>air has less of a known greenhouse gas.
>
> But not less CO2. It is the feedback notion about water vapor
>that I am arguing against

So you consider water vapor to not be a greenhouse gas?

> and the general claim of AGW of that higher
>temperature means more moisture, deserts are hot, and dry.

Deserts are both hot and cold, with temperature extremes in both
directions. Check out average nighttime low temperature in Reno in July -
and then realize how chilly you get if you lose your shirt there!
Meanwhile, the models passing tests of time are predicting Arizona to
get more humid as a reswult of AGW, with little temperature increase and
most of that to nighttime low temperatures rather than daytime high
temperatures.

>>> More moisture means more IR absorption, but moist air moderates
>>>temperature changes. CO2 has no phase change at atmospheric temperature
>>>and pressure, and has a very low activity level compared to water and water
>>>vapor and ice.
>>
>> CO2 has GHG effect in the range of 9-26% of the total GHG effect.
>
> Your claim is noted, but not agreed with on the Earth.

IR absorption spectra for the atmosphere, both as a whole and sorted
by GHG component, are cited above. Some of those cites even add blackbody
spectrum for a few relevant temperatures.

>>> At the temperatures at higher altitudes, IR radiation is sparse,
>>
>> At -40 C, IR intensity is about 43% of that achieved by the 15 degree C
>>that was close enough to the 1930-1980 average of global surface
>>temperature. -40 C is a fairly usual temperature for upper part of the
>>troposphere.
>>
>> Even -60 C has IR radiation intensity about 30% of that achieved by +15
>>C.
>
> And more of that high altitude radiation goes to space, that
>is what cools the atmosphere.

That is what cools the atmosphere avove roughly the 350 mb level.

> Can you see fit to agree that GHGs cool the atmosphere?

I agree that GHGs cool the upper atmosphere, at altitudes high enough to
not have net warming by GHGs higher up. I calculate with some significant
oversimplification that the "effective radiating level" is at about 8 km
above the surface or close to the 350 mb level. (My previous post saying
300 mb level I self-correct upon - I realize that I screwedthat one upm a
bit.)

> And can you agree the weather services temperature data is not
>the surface, it is the lower atmosphere?

It is supposed to be temperature of the air either 4 feet or 2 meters
above the surface.

>>>if the AGW "scientist" were to begin good science, they would devise
>>>experiments to show how much energy can be transferred in a given time.
>>> A colder atmosphere absorbs more from warm solids, liquids and
>>>gases, but radiates less.
>>>
>>> That means the net energy flow is upward, both from surface to
>>>high altitude, and from surface to space.
>>> And also from low altitude to high altitude.
>>>
>>> There is no net energy transfer from cold to hot.
>>
>> The truth of those (when considering source to be Sun-heated Earth
>>surface) does not negate AGW via increase of GHG.
>>
>> - Don Klipstein (don(a)misty.com)
>
> How can you reconcile that statement with the seemingly (to me)
>fact that GHGs cool the atmosphere?

GHGs cool the portion of the atmosphere high enough up to not be warmed
by GHGs even higher up.

> Can you at least agree that _IF_ GHGs cool the atmosphere, much
>of the AGW mantra is completely false?

I do agree, since GHGs do not cool the lower troposphere but warm that
region of the atmosphere - by adding impedance to radiational cooling of
the surface.

> And the historical record shows human life has benefitted from
>the "optimum" higher temperature over the last 5000 years?

Europe surely has so far. The problems with GW are expected to be from
tropical diseases expanding their ranges into areas protected from them by
winter cold temperatures, and from sea level rise should GW progress to an
extent actually melting the the thick ice sheets of Greenland and/or
Antarctica.

> Even if every facet of AGW were true, should man strive toward
>extremism of trying to create conditions that are needed for every
>species of life, both animal and vegetable on Earth, and even if it
>harms mankind?

Biodiversity is a generally stabilizing factor. A major uptick in
extinction of species reduces stability of regional ecosystems on a
worldwide basis (even if only for several millennia).
More important still if major regions having ability to produce major
economically significant agricultural products either shrink or shift
across international borders. Canada may become a major corn exporting
nation.

> If I did not think the premise that GHGs cool the atmosphere,
>and moderate the temperature of the surface, I would not be talking
>against the AGW agenda.
>
> Note that a moderated temperature can be interpreted as a
>"warming" in regions where it takes an extra 80 BTU to lower the
>temperature of water by a single degree F.

Where do you get that number from? How much water do you expect to
change temperature of by 1 degree F by shifting 80 BTU, since 1 BTU is
defined as quantity of heat that changes 1 pound of water by 1 degree F?

- Don Klipstein (don(a)misty.com)
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