Guest post by Erl Happ
This post was generated in response to the Christopher Monkton thread. It is not a criticism of Christopher Monkton but of our tendency to imagine that artful mathematicians (I am not one) are sufficiently sophisticated to deal with complex problems. Indeed the debate as to the value of feedback processes illustrates the lack of utility of mathematics when unconstrained by observation of the real world. Climate Science is full of it.
As I understand it the proposition goes like this:
Enhanced GG composition, more back radiation, enhanced evaporation, more cloud and IF cloud enhances back radiation, the surface warms. The enhancement of cloud density depending upon the IF supposedly represents the feedback.
But cloud reflects incoming energy. The feedback notion requires that the loss of energy to the surface due to cloud reflection of incoming short wave radiation is outweighed by the increase in energy trapped in the ‘below cloud level system’ due to cloud returning OLR to the surface. That’s the IF factor again.
The IF proviso requires that evaporation from the surface not only keeps pace with the increase in surface temperature. It must exceed it for cloud density to be enhanced as the surface warms.
There is a little logical problem here. If the feedback from long wave radiation exceeded the value of the reflected short wave, the oceans would soon boil. That problem is sidestepped by suggesting that it is only the high ice cloud that is important in the feedback. So, in the end the result depends upon the mix in the categories of clouds that provide net reflection versus those that provide net surface warming and whether the moisture supply to the atmosphere keeps up and somehow tips the balance towards those clouds that are supposed to provide a net warming effect .
This is already too complex and includes unknowns that are unquantifiable.
Now, lets look at the real world. Consider:
A
Do clouds warm the surface? Logically, if clouds had that effect, with more clouds the surface should warm. But near surface clouds arrive in warm tropical air. It’s warm because of its origin. The warmer and wetter it is the more the precipitation. This warm moist tropical air produces cloud and precipitation strictly in proportion to the chilling it receives. Warm that same air and the cloud disappears. (The Foehn effect). Precipitation enhances the supply of moisture at the surface cooling the surface. The air is in constant movement and the system is mind bogglingly dynamic. But one constant is the decline of surface temperature as we move from equator to pole. Satellites show that warm moist tropical air travels all the way but is dried as it moves. Hence the polar latitudes are cold deserts with the air in these regions containing little moisture that remains to be precipitated producing a gradually accumulating mass of ice in perennially sub freezing temperatures. Lesson: The presence of low clouds reflect very recent change in air temperature and is unrelated to the supply of moisture to the atmosphere from the surface. The presence of these clouds depends upon the supply of energy to the tropical ocean and the direction of the wind.
B
In mid latitudes the atmosphere between 600hpa and 100hpa (where the ice cloud called cirrus and stratus is located) responds in terms of its cloud cover to a moisture supply from places remote to the point of observation. (tropical convection, polar frontal action). Supply is relatively invariable and as a result cloud comes and goes according to flux in the temperature of the upper troposphere. Temperature in this zone is a function of ozone content and depends upon stratospheric processes. In the mid latitudes the troposphere above 300hPa contains appreciable ozone and peaks in temperature in mid winter when outgoing radiation peaks. At this time the surface reaches its seasonal minimum temperature. Radiation peaks in winter due to the enhancement of the high pressure cells of descending warming air in the winter hemisphere. The temperature of the cloud bearing layer does not relate at all to change in surface temperature. If radiation increases the presence of ozone ensures that the air warms and the cloud disappears.
C
For cloud to increase as the atmosphere warms it requires that evaporation is enhanced as the surface warms so as to enhance relative humidity promoting enhanced cloud cover. This proposition is tested once a year in the northern hemisphere. Because of the preponderance of land which is opaque to short wave radiation (unlike the sea) near surface air temperature increases strongly. In effect the surface returns warmth to the atmosphere by conduction and radiation. The convective process of heat loss via decompression (that we see in the tropics) is inoperable because of an insufficiency of moisture supply to the atmosphere. Transfer by conduction and radiation is therefore enhanced and the entire troposphere warms.
We see here that vvaporation fails to promote the addition of sufficient moisture to the atmosphere to maintain cloud cover. So, cloud falls away and global air temperature peaks in July in conformity with this strong seasonal influence driven by the accident of geography which is the northern hemisphere. A potential runaway feedback system that is the exact opposite of that posited above (warming surface more cloud) is curtailed by the passage of the Earth around the sun while it spins on its tilted axis.
In January, when the suns irradiance is 7% stronger due to orbital considerations global near surface air temperature reaches its minimum because global cloud cover peaks. Taken in its entirety, cool the Earth’s atmosphere and cloud increases. The surface cools. It will cool in the face of enhanced radiation.
Summarizing: Does the presence of cloud result in surface warming? No. In January, global cloud cover is 3% greater than July. Irradiance 7% greater. Surface temperature 4° cooler. Will a warmer sun heat the Earth? Not necessarily. It depends upon what happens to the cloud. If there were less land and more sea the ocean would gradually warm.
D
The proposition that cloud is enhanced as the near surface atmosphere warms is also testable by looking at historical data for precipitable water as the globe has warmed. Reanalysis tells us that it actually falls away.
E
The Earth system also demonstrates what happens when additional greenhouse gas is added to the troposphere. This happens in the coupled circulation over Antarctica. The system waxes and wanes according to the activity of the night jet in modulating the ozone content and temperature of the upper stratosphere. The convection that results involves warmer ozone rich air (10ppm) ascending. Relatively ozone poor stratospheric air (say 7ppm) descends into the troposphere (naturally containing ozone at the ppb level) that in consequence becomes ozone rich. The consequence is gross warming of the troposphere on the margins of Antarctica and the generation of the lowest surface atmospheric pressures on the planet. The flux in pressure in this zone depends simply upon the rate of ozone churn into the troposphere. Ozone is carried towards the equator by the counter westerlies destroying cloud as it moves by virtue of its greenhouse gas property. It absorbs at 9.6 micrometers.
As this greenhouse gas is added to the troposphere cloud cover falls away. The surface temperature feedback is due to enhanced shortwave radiation, not longwave retention. This too is a potentially disastrous feedback scenario that is limited by the fact that the ozone content of the stratosphere varies within limits and the Earth’s surface is mainly water which soaks up energy without adding a lot of moisture to the atmsophere. Given enough time, the feed rate of ozone peaks and shortly after atmospheric moisture and cloud cover recovers.
F
The prime source of long wave radiation emanating from the Earth system is the high pressure cells of the winter hemisphere where the air warms by compression as it descends, a cloud free zone promoting surface warming when it is most needed…………..despite the abundant long wave radiation streaming out to space.
Conclusion : Cloud cools.
So lets look at this…
“Enhanced GG composition, more back radiation, enhanced evaporation, more cloud and IF cloud enhances back radiation, the surface warms.”
So, to begin with, enhanced GG composition, specifically CO2, check, there is more CO2.
More back radiation, is there more now that there is more CO2? Lets look at that.
Interstellar Bill says: (on this thread http://wattsupwiththat.com/2011/09/27/monckton-on-pulling-planck-out-of-a-hat/#more-48277 )
September 27, 2011 at 8:47 pm
I’ve done lots of of infrared sky-temp measurements,
thirty-five years ago, and today, with the same pyrgeometers.
Their unchanged readings contrast sharply
with Alarmism’s computer-predicted increases.
http://en.wikipedia.org/wiki/Pyrgeometer
There is NOT more back radiation despite more CO2.
STOP.
Without that more back radiation, there is no enhanced evaporation, and no more clouds, which enhance it further.
There is NOT more back radiation.
Conclusion, the entire chain of reasoning here is irrelevant, the initial conditions have not been met to even START this chain of events.
Lets put it in terms of formal logic.
Let us call “enhanced GG composition” A.
Let us call “more back radiation” B.
Let us call “enhanced evaporation” C.
And let us call ” more cloud and IF cloud enhances back radiation, the surface warms” D.
The theory of global warming states:
If A is true then B.
If B is true then C.
If C is true then D.
A is true.
B is NOT TRUE.
Therefore neither are C or D.
It all depends entirely on B, “more back radiation”, this can be measured with a Pyrgeometer, it has been, and there is not more back radiation.
Conclusion, the entire logic of global warming is falsified due to false premise seen by direct observation.
Note also that if B is not true, it is irelevent if clouds enhance background radiation, since if B is not true, we never get to D to begine with.
What is needed is a worldwide measrement of background radiation at the surface over as long a time period as possible, which we have the instruments for and have had for a long time. We then make that into a graph, and overlay that with a graph of incrweasing CO2. If the CO2 goes up, which it has, yet the background radiation does not, we therefore see, once and for all, by direct measurement, that the entire idea of global warming has been scientifically falsified by a direct application of the scientific meathod.
So lets get with it.
This is a science site, right?
izen says:
September 28, 2011 at 6:54 am
You have the theory right. You need to supplement it with some experience. Start with Eschenbach’s thunderstorm model. That model captures the very dramatic pattern that dominates central and south Florida during summer (May – September). The high is well above 90 daily and evaporation is huge. The thunderstorms, coming from both coasts, arrive in Orlando between 3 and 5 PM daily. The result is huge cooling. Temps drop from 95 to 85 and stay down. If the storms are carrying a lot of water the temps can drop 20 degrees.
The overall effect is cooling that seems never to make it into Warmista factual records. Sure, the daily summer high in central Florida is 90 to 95 but it falls off a cliff about two hours later.
Unless we are talking about THUNDERSTORMS, as a private pilot, I can tell you most cloud cover on “cloudy nights” is “stratus”…I.e., 6000 feet to 12,000 feet. THUS a LARGE FRACTION OF THE ATMOPSHERE is above them and has NO interruption in OLR during the night. SO we need to deal with “net” effect. Overall, since the clouds have reflected 50% of the incoming short wave (compare like 15% from land and sea), it doesn’t take .01% statistics and years of data to work out the balances and show they favor “cooling” versus warming.
Just more misinformation that vaguely masquerades as science. Much like Joe Bastardi’s own dramatically failed prediction for 2011 Arctic Sea ice.
http://wattsupwiththat.com/2010/11/23/joe-bastardis-2011-arctic-sea-ice-prediction/
NSIDC shows us at second lowest on record. Bremen shows us first. Volume still in terminal decline.
I only post this because I care about you guys. It’s nice to keep heads in sand so long as they don’t bake there.
There’s a great paper/video that talks about how impossible it is to convince people about the facts of AGW if they are not well versed in science/math to begin with. About 10% of the population has sufficient science intellect to grasp the intracies of climate change. That means that we realists can preach all we want to the poorly educated all for naught.
http://www.sms.cam.ac.uk/media/1083337
The Yale study says that most people rely on first contact to get their impressions of the competency of a source. So if your neighbor tells you that Gore is the greatest climatologist since God, absent any immediate influence to the contrary, they buy it. In other words, trying to convince the 90% who are science illiterate may be futile.
As much as I enjoy preaching to the choir, it’s the sinners in the parish I worry about.
Erl Happ: Your post includes the following fatal flaw, primarily because you are considering only global surface temperatures and global cloud cover.
You wrote, ”In January, when the suns irradiance is 7% stronger due to orbital considerations global near surface air temperature reaches its minimum because global cloud cover peaks. Taken in its entirety, cool the Earth’s atmosphere and cloud increases. The surface cools. It will cool in the face of enhanced radiation.”
And that plus some preceding discussions brought you to the following conclusion, “Summarizing: Does the presence of cloud result in surface warming? No. In January, global cloud cover is 3% greater than July. Irradiance 7% greater. Surface temperature 4° cooler. Will a warmer sun heat the Earth? Not necessarily. It depends upon what happens to the cloud. If there were less land and more sea the ocean would gradually warm.”
The reality:
The seasonal variation in global surface temperature is dominated by the Northern Hemisphere:
http://i54.tinypic.com/mbn7eo.jpg
And that of course is dictated by the dominance of the variations in Northern Hemisphere Land Surface Temperatures:
http://i56.tinypic.com/2d1we2t.jpg
But, the seasonal variation in cloud amount is dominated by the Southern Hemisphere, which has much greater variability over the course of a year and a significantly higher cloud amount than the Northern Hemisphere. More ocean surface area yields more cloud cover maybe, Erl?:
http://i56.tinypic.com/23iw8c0.jpg
And if you were to compare the seasonal cycles per hemisphere, you’ll note that the hemispheric cloud amounts vary somewhat in synch with the hemispheric surface temperatures, more toward the SST data than LST data, indicating that on a hemispheric basis, when surface temperature rises and falls, cloud amount rises and falls.
“…oceans would… boil…”
You lost me right there. TerryS has it right – a positive feedback doesn’t necessarily/usually lead to a runaway effect. It just leads to a different equilibrium state. I would say the original post is a bad advert for optimism/skepticism on climate science. There are plenty of better/quantitative/empirical arguments.
With all due respect, Erl you are not an engineer and have not quite grasped heat transfer occuring at surfaces but it seems you have a better idea than most of those you call themselves climate scientists. There are four types of heat transfer at surfaces 1/ conduction which occurs within solids and is described by Fourier’s law; conductivity is analogous to the reciprocal of resistance in an electrical circuit 2/ convection natural and forced occurs with fluids (liquids & gases); engineers have determined analogies between momentum transfer and heat transfer. 3/ phase change -mainly associated with a change of liquids to gas and vice versa but can include liquids to solid and solids to gas (eg clouds of CO2 crystals as on Venus) -clouds in earths atmosphere consist of droplets of water and particles of ice 4/ radiation. The alarmists seem to think radiation is the “only game in town” when in fact radiation in some wavelengths may not occur at all. CO2 only absorbs and radiates in very narrow wavelength range and only if there is difference. People in cold countries would be aware of chill factors due to forced convective heat loss by the wind. Convective heat transfer will occur within clouds between air and the surfaces water droplets and ice particles. Mass transfer usually accompanies heat transfer by convection and phase change. It seems that climate scientist confuse convection with mixing.
Overall, as others have indicated the energy transfers in the atmosphere are very complex and certainly can not be modelled by linear equations.
kim says: ” I wish you and Robert Ellison and Stephen Wilde and Bob Tisdale and a few others would collaborate.”
Refer to my comment above. and to my discussions with Erl on his prior post starting here:
http://wattsupwiththat.com/2011/09/22/where-is-science/#comment-752420
“Enhanced GG composition, more back radiation, enhanced evaporation, more cloud and IF cloud enhances back radiation, the surface warms. The enhancement of cloud density depending upon the IF supposedly represents the feedback.”
I have a logical disconnect between the “enhanced evaporation” and “more cloud”. The greater back radiation will increase the surface temperature, leaving the dew point temperature the same. So the relative humidity drops. Evaporation enhances, yes, but the new relative humidity level will be slightly less than the original relative humidity level. The abundance of cloud, one presumes, is a function of the relative humidity. So this will tend to slightly lesser amounts of cloud, but slightly greater absolute humidity. The greater absolute humidity will tend to warm due to enhanced back radiation. The slightly lesser amounts of cloud will tend to reflect less sunlight, thus also tending to warm, creating overall positive feedback.
Of course I am merely questioning the logic in the presentation rather than making any comments on the actuality of the physics in the atmosphere.
Re: “… a positive feedback doesn’t necessarily/usually lead to a runaway effect. It just leads to a different equilibrium state.”
Yes, consider the negative feedback example of a boss intending to give an employee a “take-home” bonus of $100:
Boss: Here’s a $100 bonus, go enjoy a $100 meal with your wife.
Empl: Thanks Boss, but my tax rate is 50% so that will only buy us a $50 meal.
Boss: Oh sorry, here’s another $50 to make up the shortfall.
Empl: Thanks again Boss, but now you’ve given me $150, so after taxes I only have $75
Boss: Crap, here’s another $25.
Empl: Still $12.50 short
… and so on until they get to a $200 forcing resulting in a $100 equilibrium.
Now if the tax rate was >= 100% (like here in Canada ;), an infinite number of dollars still wouldn’t result in a $100 equilibrium.
HankH says: September 28, 2011 at 4:25 am
Hank, you are coming across as a first principles thinker who likes to get to the basics. I like that. The most appropriate temperature has got to be the one that maximizes plant growth and as you point out its 25°C. For sustenance you can’t beat a warm winter and a hot summer with the opportunity for double cropping. It’s no accident that southern China and the Indian subcontinent have a high population density. They wear a shirt and shorts most of the year which is not a bad way to go. Much of the globe is miserably cold most of the time. We could definitively do with a bit more warmth. It’s good to get right down to the basics.
Dave Springer says: September 28, 2011 at 4:32 am
So long as the earth is a water world it is the water cycle which governs the climate response. Write that down.
So long as the earth is a water world it is the water cycle which governs the climate response.
Delicious.
kim says: September 28, 2011 at 6:19 am
Thanks for your confidence Kim. It’s about four years now since I started making a nuisance of myself at Climate Audit and I am a lot closer today, just a question of explaining it adequately. It’s always a delight to find a comment from Kim.
Bob Kutz says: September 28, 2011 at 6:27 am
Your explanation is precisely the way I am reading it Bob. Temperature is pretty well a function of wind direction.
It’s often observed that deserts cool down rapidly at night. Better to live next to a big lake where the water stays warm than live in a place where the water in the kettle turns to ice overnight and the air is both bitingly cold and shockingly dry. It’s not the cloudless nature of the place. It’s the lack of a decent store of warmth that accounts for the freeze.
If you measure the down-welling radiation on a cloudy night you are measuring down-welling radiation in warm moist air. Of course there is going to be more of it about.
George E. Smith says: September 28, 2011 at 6:51 am
But I would suggest that the hot dry deserts of the middle East and north Africa are the source of a lot more LWIR and it is shorter wavelength than the cool zones, so it escapes CO2 easier. Remembert hat T^4 effect, and Wien’s law.
Great point. There is nowhere on the Earth that gives off more radiation directly from the surface. That great diurnal temperature range in the desert gives us an idea of the energy residence time. Oh for a greenhouse effect. Where is it when you really need it? OK I will settle for a wind off the sea. Day and night.
izen says: September 28, 2011 at 6:54 am
warming from any cause gets a positive feedback from increased water vapor
Not in the northern hemisphere in summer.
Not in the desert
Not over cold ocean or ice
Not as much in still air
Less over the ocean than over rain forest
And where does the water vapour appear? Is it at lower levels where the cloud is said to be reflective. Does it rise into the middle and upper troposphere to form ice cloud. Ice cloud has a much greater reflective area than water droplet cloud. At what point in terms of elevation does the back-radiation effect become ineffective in terms of raising surface temperature?
tom T says: September 28, 2011 at 7:24 am
Tom, here is another perspective:
Viewed from space the troposphere is so thin as to be indistinguishable from the actual surface of the Earth. The Earth has a diameter of 12,756 km. If the Earth were a mattress with a thickness of 300mm and it were to be covered in a blanket in the proportion that the troposphere bears to the Earth itself, that blanket would be just 0.35 mm in thickness, the equivalent of about five sheets of newspaper. It is the nature of the troposphere that it is hopelessly unstable. Imagine sleeping in the nick under five sheets of newspaper with the lowest one removed every thirty seconds and placed on top. Occasionally someone comes with a watering can to make sure that you are not overheating. That is the sort of greenhouse we live in.
Bob Tisdale says: September 28, 2011 at 8:15 am
Thanks for your contribution Bob. I have a different understanding of the phenomenon.
January: http://climatechange1.files.wordpress.com/2011/09/jan.jpg
July: http://climatechange1.files.wordpress.com/2011/09/july.jpg
It is evident that all the driest parts of the land have less cloud in July than they do in January. It is also plain that there is less cloud in July than in January.
Paradoxically, there is more dark blue (less cloud) between the equator and 30° south in southern winter (July) than in summer. This follows from the fact that the great high pressure cells of the Hadley circulation favor the winter hemisphere. Massive low pressure cells form over land in the northern hemisphere as the land heats up. The air must come down somewhere and as it does so, that area will lose cloud due to compressive warming, the bike pump effect.
In mid year the global atmosphere warms. As it does so cloud cover falls away but due to circulatory influences most of the loss is in the southern hemisphere.
Cementafriend says: September 28, 2011 at 8:20 am
as others have indicated the energy transfers in the atmosphere are very complex and certainly can not be modelled by linear equations.
That is exactly the point that I set out to make.
peter_ga says: September 28, 2011 at 8:27 am
Your point is well made. I failed to elaborate on the changed humidity relations. And since changed absolute humidity per-se is postulated to be the source of amplification (as well as high altitude cirrus cloud) one needs to be sure that humidity actually increases as the CO2 content of the air increases. The evidence from reanalysis data shows that total precipitable water increases with sea surface temperature but the increase in atmospheric moisture failed to keep pace with SST in successive El Nino episodes between 1978 and 1998. So, relative to the temperature of the sea, precipitable water lagged and one would suggest, with it, cloud cover. However, over the last seven or eight years, as CO2 has continued to increase, precipitable moisture has staged a remarkable recovery.
This should tell us that the relationship is not simple and that some other factor than Greenhouse Gas influence is probably responsible for the warming that has occurred. Certainly it appears that a decline in cloud cover was likely an important factor explaining the warming while an increase in cloud cover over recent years is consistent with a cessation of that warming.
Anyway, no consistent link between CO2 and atmospheric water vapor content.
Here’s an IF. IF clouds affect the climate by providing a change in the sensitivity of the climate, you could have a scenario where clouds actually regulate the Earth’s temperature and provide a throttle of sorts. Say that an increase in WM^2 causes an increase in cloudiness that decreases the sensitivity of the climate by increasing the thermal mass of the atmosphere. Say you go from (simplifying, of course) 2W/M^2 to 3. And this lowers the sensitivity from .75 to .5. You have 2*.75=1.5 and 3*.5=1.5.
C. Summarizing: Does the presence of cloud result in surface warming? No. In January, global cloud cover is 3% greater than July. Irradiance 7% greater. Surface temperature 4° cooler. Will a warmer sun heat the Earth? Not necessarily. It depends upon what happens to the cloud. If there were less land and more sea the ocean would gradually warm.
It is also very useful to consider the diurnal progression: overnight the surface and near surface cool; after sunrise, surface and near surface start to warm, and continue warming; the warming produces all the usual effects such as increased water vapor content, thermals, and eventually towering clouds; the clouds spread out, and the net effect of clouds is to reduce direct solar irradiance while increasing the feedback, a net cooling effect; in line with Willis Eschenbach’s hypothesis, the warmer the early daytime, the bigger the clouds and the bigger the net cooling effect of the clouds; late afternoon and evening produce rain, fog, or dew; then there is overnight cooling. Notice that through all of this, the discrepancy between actual temperatures and energy flows, and their equilibrium approximations is not very great.
What happens if atmospheric CO2 doubles? AM warming is about the same, heat retention near surface (and down radiation) are increased, water vaporization is increased, cloud formation is increased, and the cooling effect of the clouds is increased. It is possible in this scenario that the effect of increased CO2 is to decrease pm temperatures near surface, by increasing the rate of transfer of heat from low troposphere to high troposphere. Again, the effect is small compared to the equilibrium distributions of water vapor and heat, but important for crops and other aspects of human civilization.
I expect Willis Eschenbach’s work to stimulate work like his by others. Important evidence probably resides in the TAO data sets that he brought to our attention.
This is not a disagreement with Erl Happ, merely an elaboration of other possibilities..
I wrote: by increasing the rate of transfer of heat from low troposphere to high troposphere.
I omitted the increased effect that the clouds would have have on reflecting the incoming light.
Erl Happ says: “Thanks for your contribution Bob. I have a different understanding of the phenomenon.
January: http://climatechange1.files.wordpress.com/2011/09/jan.jpg
July: http://climatechange1.files.wordpress.com/2011/09/july.jpg”
I presented graphs with the souces of the data and the time span identified, and you reply with maps of a January and a July–or are they a collection of Januarys and Julys? Please plot the annual variations in the data per hemisphere as I had in my graphs and identify your source.
Erl,
Monckton spells his name with a ‘c’ as well as a ‘k.’
“”””” izen says: September 28, 2011 at 6:54 am
warming from any cause gets a positive feedback from increased water vapor
Not in the northern hemisphere in summer. “””””
Well izen is quite wrong; and it would be much easier for people to understand the issue, if they stood back and took a look and realized that IT IS THE SUN THAT DRIVES THE SYSTEM !!!
70% of the earth surface is water; and in the tropics (+/- 23.5 deg Lat) more than 75% of the surface is deep oceans.
Sunlight penetrates to around 700 metres, and deposits 97-8% of its energy in that water body.
Earth’s Temperature ultimately depends on how much solar energy is stored in that ocean water. It eventually emerges into the atmosphere and other systems to create climate.
WATER; H2O IN ANY FORM; SOLID/LIQUID/GAS ABSORBS A LOT OF SUNLIGHT Maybe 20% of the incoming solar spectrum at wavelengths from around 700 nm to 4.0 microns. 44% of the solar energy is in that range at the surface, and only 1% extends beyond 4 microns. Water may absorb as much as half of that 700 to 4,000 nm spectral range of energies. I’ll let you MODTRANS fans do that calculation.
So every single additional molecule of H2O that makes it into the atmosphere, from evaporation or plane/car engine exhausts or airliner toilet dumps will capture more solar energy so it NEVER reaches the deep oceans.
The solar energy that water vapor captures, DOES heat the atmosphere. As a result, the atmosphere radiates MORE LWIR radiation. That emission is ISOTROPIC so half of it goes upwards and escapes to space (eventually) and ONLY HALF comes down to the surface (downwelling radiation).
So that is A NET LOSS OF ABOUT HALF of the incoming solar energy that was captured by water vapor.
Moreover, the half that arrives at the surface as enhanced LWIR emissions from the atmosphere, DOES NOT get stored in the deep oceans; it is absorbed in the top 10-50 microns of the water surface, where it most likely results in prompt evaporation of MORE WATER VAPOR.
Along with that extra water vapor,comes a lot of LATENT HEAT OF EVAPORATION that removes even more heat from the ocean system. There can be very little extra heat going into the deep ocean from surface absorption of down LWIR radiation; downward conduction is TRUMPED BY UPWARD CONVECTION.
Oh I almost forgot; more water vapor (evaporation) means MORE CLOUDS; …SOMEWHERE !!!
Yes the conditions that create evaporation may not lead to local clouds. Fear not, because ALL of that extra H2O MUST come back down as precipitation somewhere. Evap= precip, is one of the axioms of climatology. Where I come from it is traditional to have clouds accompany our precipitation; and more clouds (anywhere) means, and more sunlight reflected to spac means more albedo, and even more sunlight reflected back into space.
Read Frank Wentz et al, SCIENCE, for July-7 2007. “How much more rain will global warming bring.” Answer is 7% more per one deg C rise in mean earth surface Temp. He measured it.
And Bob Tisdale has mentioned that number on many occasions here at WUWT. Something to do with somne “Clausius Clapeyron equation”, so even the modellers agree with that 7% number.
And one other factoid. Evaporation is a consequence of the Temperature of THE LIQUID; NOT THE ATMOSPHERE. So it is sunlight plus LWIR that causes evaporation. Yes the atmosphere Temperature and winds will affect the rate of evaporation. I’m NOT a chemist; but it relates to the fact that any bidirectional chemical reaction will come to a screeching halt if you do not remove the reaction products from the scene of the crime. So winds whisking the newly evaporated H2O molecules away from the surface is essential to rapid evaporation; but it is only the liquid surface Temperature that determines IF evaporation will occur.
So please stop talking about these entirely peripheral minutiae, like where and how clouds form and what time of the year that happens. If EVAPORATION occurs “somewhere”, you can bet your life savings that both CLOUDS and PRECIPITATION will occur somewhere else.
So no CLOUDS are NEVER a positive feedback NO MATTER WHAT, as Dr Bill Shockley would put it in one of his classes. To the best of my knowledge, Bill Shockley never taught climatism
Andy Mayhew says:
September 28, 2011 at 3:27 am
If clouds only cool, why are cloudy nights warmer than clear nights? Maybe it’s not QUITE as simple after all?
Thank you, Andy!
So Erl has no idea what a Foehn wind is?
George E. Smith says: “And Bob Tisdale has mentioned that number on many occasions here at WUWT. Something to do with somne “Clausius Clapeyron equation”, so even the modellers agree with that 7% number.”
I have? Please provide a link.
Erl Happ says: “Thanks for your contribution Bob. I have a different understanding of the phenomenon.
=
Whatever suits you Erl… LOL
Reminds me of that Marx line, I mean Groucho of course: “Those are my principles, and if you don’t like them… well, I have others.”
“”””” Bob Tisdale says:
September 28, 2011 at 1:50 pm
George E. Smith says: “And Bob Tisdale has mentioned that number on many occasions here at WUWT. Something to do with somne “Clausius Clapeyron equation”, so even the modellers agree with that 7% number.”
I have? Please provide a link. “””””
OOoops ! Gee have I got you and Bill Illis mixed up again Bob ?
Sorry about that.
“”””” Ed says:
September 28, 2011 at 1:04 pm
Andy Mayhew says:
September 28, 2011 at 3:27 am
If clouds only cool, why are cloudy nights warmer than clear nights? Maybe it’s not QUITE as simple after all?
Thank you, Andy! “””””
Does everybody just post what comes to mind, and never read ANY of the responses ?
Ed, I’ll tell you exactly what I already told Andy; that you apparently never bothered to read.
He has it exactly backwards, as I have posted MANY times here at WUWT; maybe I’m just wasting my time.
What Andy should have said; which IS accurate is that warmer nights tend to be cloudier than cold nights.
It is warm moist conditions DURING THE DAY that leads to high clouds at night, once the warm moist air rises and cools down to the dew point and clouds form. It still COOLS DOWN on those nights; it does not HEAT UP .
And the warmer it is during the moist day, the higher that air has to go to get down to the dew point, so the higher the cloud layer forms.
The warmth during the day produces the clouds; the clouds DO NOT produce the warm night.
Does it make ANY rational sense at all (with no physics knowledge needed) to believe that the higher a cloud layer is, containing LESS AIR, and LESS MOISTURE and LOWER TEMPERATURE, and LOWER PRESSURE; the more back radiated energy it sends back to the surface.
By that rationale, it must be those stratospheric Noctilucent clouds; that are pretty much super cold near vaccuums that are most responsible for heating the earth. If those clouds moved oput to the moon would they warm us even more.
That notion is totally silly, and one doesn’t have to be a scientist to understand that.
Good to see some acknowledgement of the year in the discussion.