Guest Post by Willis Eschenbach
There is an interesting new study by Lauer et al. entitled “The Impact of Global Warming on Marine Boundary Layer Clouds over the Eastern Pacific—A Regional Model Study” [hereinafter Lauer10]. Anthony Watts has discussed some early issues with the paper here. The Lauer10 study has been controversial because it found that some marine stratocumulus clouds decrease with increasing warming. This is seen as an indication that (other things being equal) clouds are a net positive feedback, that they will amplify any warming and make it even warmer. This finding has engendered much discussion.
I want to do a different analysis. I want to provide a theoretical understanding of the Lauer10 findings. Figure 1 shows the larger picture, within which Lauer’s results make sense. This is the picture of part of the Earth as a solar-driven heat engine.
Figure 1. Very simplified picture of the main driving loop of the tropospheric circulation. A large counter-rotating cell (a “Hadley Cell”) of air exists on each side of the equator. Energy enters the system mostly around the equator. Thunderstorms (shown with rain) drive deep convection currents from the surface to the upper troposphere. Some of the energy is transferred horizontally by the Hadley Cells to the area at 30N/S. There, some the energy is radiated out to space. A large amount of the radiation occurs in the clear dry desert regions. Other parts of the atmospheric circulation not shown.
Lauer10 is discussing the low cloud decks found off the western edges of the continents at around 30°N/S, as illustrated in Fig. 1.
Considering the earth’s climate as a heat engine can lead us to interesting insights. First, we can see how the heat engine works. The thunderstorms in the wet tropics convert some of the incoming solar energy to work. The work consists in part of moving huge amounts of warm air vertically. In the process, most of the moisture is stripped out of the air, producing the rain shown in Fig. 1. After rising, some of this now-drier air travels polewards. It descends (subsides) in the region around 30° north and south of the Equator. This dry descending air forms the great desert belts of the planet. The air then returns equator-wards to repeat the cycle.
A closed system heat engine (like the climate) needs some form of radiator to cool the working fluid before it returns to be recycled through the engine. In the climate, the areas around 30°N/S serve as the main radiators for this loop of the atmospheric circulation. There, excess energy is radiated to space.
Now, here’s the theoretical question:
What would we expect to happen to this flow system if there is an increase in the temperature?
The Constructal Law says that in such a case, a flow system like the climate will rearrange itself to “speed up the wheel”. That is to say, it will change to increase the throughput of the system. The system reorganizes itself to increase the total of work plus turbulence.
How can the circulation shown in Fig. 1 become more efficient and increase its throughput? There are not a whole lot of control points in the system. The main control points are the clouds at both the hot and the cool ends of the heat engine.
The Constructal Law suggests that as the system warms, two things would happen. First, there would be an increase of cumulonimbus (thunderstorm) clouds at the equatorial end of the system. This would increase the speed and volume of the Hadley circulation. Next, there would be a decrease of clouds in the area around 30° latitude. This would increase the amount of radiation leaving the system. These changes would combine to increase the total throughput of the system.
In that light, let us re-consider the results of Lauer10. What they show is that as more heat passes through the system, as expected, the clouds at the radiator end of the system decrease. This increases the amount of energy that can pass through the system in a given time. In other words, they are an expected result of the system warming.
Lauer10 appears to discount this possibility when they say:
The radiative effect of low marine clouds is dominated by their contribution to the planetary albedo as their impact on outgoing longwave radiation is limited because of the small temperature difference between cloud tops and the underlying surface.
I found this doubtful for a number of reasons. First, the cloud top for marine stratiform clouds is typically at an altitude of ~600-700 metres, and the cloud bottom is at around 400-500 metres. The dry adiabatic lapse rate (cooling with increasing altitude in dry air) is about 1°C per hundred metres. This puts the cloud base at around five degrees C cooler than the surface. Then we have 200 metres at the wet adiabatic lapse rate, that’s about another degree. Total of six degrees cooler at the cloud tops.
The annual average surface temperature at 30°N is about 20°C, which puts the cloud tops at about 14°C. While this doesn’t seem like a lot, it gives a blackbody radiation difference of about 30 W/m2 … hardly a “limited” difference. Even if it is “only” half of that, 15 W/m2, that is the equivalent of four doublings of CO2.
Next, the strength of the solar contribution at 30° latitude is only about 60% of equatorial sunshine. This is due to the greater angle to the sun, plus the greater distance through the atmosphere, plus the inherent increase in albedo with decreasing solar angle.
Next, there is a fundamental difference between equatorial clouds (cumulus and cumulonimbus) and the stratocumulus decks of the area at 30° latitude. This difference is ignored by the averaging, with which climate science is unfortunately rife.
The problem is that the timing of clouds is often more important than the amount. Consider someplace in the tropics that has say eight hours of clouds per day. If those clouds are in the afternoon, the reflection of the sunlight will dominate the effect of the clouds on radiation. The clouds will cool the afternoon, as we all know from our common experience.
If that same eight hours of clouds occurs at night, however, the situation is reversed. Clouds are basically an impervious black body to outgoing longwave radiation. Because of this, they increase the downwelling LW when they are overhead. During the day this is usually more than offset by the reduction in solar radiation.
But at night there is no sun, so the effect of night-time clouds is almost always a warming. Again this is our common experience, as clear winter nights are almost always colder than winter nights with clouds.
However, all of this is obscured by the averaging. In both the day and night cases above, we have the exact same amount of clouds, eight hours per day. At night the cloud warms the earth, during the day the same cloud cools the earth, and averages can’t tell the difference.
The relevant difference between stratocumulus at 30° latitude and the equatorial clouds is that the equatorial clouds die out and vanish at night. This allows for free radiation from the surface. The stratocumulus deck, on the other hand, persists day and night. This means that it has much more effect on radiation than equatorial cloud.
Finally, I think that there is a fundamental misunderstanding in their claim that the maritime stratocumulus cloud “impact on outgoing longwave radiation is limited” because of the small temperature difference.
It is true that between the upwelling longwave from the surface and from the low clouds is about 10% (30W/m). The temperatures are not hugely dissimilar. But the internal energy flows are very different under the two conditions (clear and cloudy).
Consider a night-time hour with cloud. The cloud is radiating through clear dry air above to space at something like 370 W/m2. In addition, the cloud is radiating roughly the same amount back to the surface, something like 370 W/m2. Meanwhile, the ocean surface is radiating (losing) around 400 W/m2.
So the ocean loses 400 and gains 370 W/m2, so it is losing 30 W/m2 in this part of the transaction.
Now take away the cloud for an hour. The surface is still radiating something like 400 W/m2, this time out to space. So the authors of Lauer10 are correct, there’s not much change in outgoing LW, “only” 15 to 30 W/m2. But what they are neglecting is that the ocean is no longer receiving 370 W/m2 of LW from the cloud. Instead, above the ocean is mostly dry air, which provides little downwelling radiation to the surface. In this case the surface itself is losing about 400 W/m2.
So despite having identical energy flows to space, these two conditions have two very different net internal energy flows. When the sky is clear, the ocean is losing energy rapidly. When it is overcast with marine stratocumulus, the ocean loses energy much more slowly. The difference in ocean loss is 370 W/m2, which is a large difference. That is why I don’t agree that the clouds make little difference to the radiation balance. They make a big difference to net energy flows (into and out) of the ocean.
And why are oceanic net energy flows important to the outgoing radiation? It is the long-term balance of these flows across the ocean surface that determines the oceanic (and therefore the atmospheric) temperature. As a result, small sustained imbalances can cause gradual temperature shifts of the entire system.
I think I notice the problem because of my training as an accountant. A small difference in the amount of payments can mask a huge difference in the source of those funds. And a small amount of income or expense adds up over time.
My conclusions?
1. I think it quite possible that Lauer’s findings are correct, that increased warming in the area of the persistent marine stratiform layers at 30°N/S leads to decreased clouds in those areas.
2. I think that Lauer’s finding are an expected effect when we consider the Earth as a heat engine operating under the Constructal Law. With increasing heat, the Constructal Law says the system will adapt by increasing throughput. Reduced cloudiness at the cold end of the heat engine is an expected change in this regard, just as we expect (and find) increased cloudiness at the hot end of the heat engine with increasing heat.
3. Of course, for this study to truly be science I need to insert the obligatory boilerplate. So let me note that mine is a preliminary study, that “further investigation is warranted”, that I could use a big stack of funds to do just that, that I will require a personal assistant to undertake the onerous task of archiving a few datasets per year, and that Exxon has been most dilatory in their payment schedule …
FURTHER INFORMATION
Constructal Law and Climate (Adrian Bejan, PDF)
The constructal law of design and evolution in nature (Adrian Bejan, PDF)
A previous post of mine on Constructal Law and Flow Systems
The constructal law and the thermodynamics of flow systems with configuration (Adrian Bejan, PDF)
Addendum before posting. After writing the above, I noted today a new paper published in Science (behind a paywall) entitled Dynamical Response of the Tropical Pacific Ocean to Solar Forcing During the Early Holocene, Thomas M. Marchitto et al. It is discussing one of the geographical areas that Lauer10 analyzed, the eastern Pacific off of Mexico. The abstract says:
We present a high-resolution magnesium/calcium proxy record of Holocene sea surface temperature (SST) from off the west coast of Baja California Sur, Mexico, a region where interannual SST variability is dominated today by the influence of the El Niño–Southern Oscillation (ENSO). Temperatures were lowest during the early to middle Holocene, consistent with documented eastern equatorial Pacific cooling and numerical model simulations of orbital forcing into a La Niña–like state at that time. The early Holocene SSTs were also characterized by millennial-scale fluctuations that correlate with cosmogenic nuclide proxies of solar variability, with inferred solar minima corresponding to El Niño–like (warm) conditions, in apparent agreement with the theoretical “ocean dynamical thermostat” response of ENSO to exogenous radiative forcing.
In short, their study reports that when the ocean gets warmer at the equator, it gets cooler at 30°N, and vice versa. They also find that this effect is visible on annual through millennial timescales. Unsurprisingly, this is not found in the GCMs.
Intrigued by the idea of a “ocean dynamical thermostat”, I read on:
Values in the middle of this range are sufficient to force the intermediate- complexity Zebiak-Cane model of El Niño–Southern Oscillation (ENSO) dynamics into a more El Niño–like state during the Little Ice Age (A.D. ~1400 to 1850) (3), a response dubbed the “ocean dynamical thermostat” because negative (or positive) radiative forcing results in dynamical ocean warming (or cooling, respectively) of the eastern tropical Pacific (ETP) (4). This model prediction is supported by paleoclimatic proxy reconstructions over the past millennium (3, 5, 6). In contrast, fully coupled general circulation models (GCMs) lack a robust thermostat response because of an opposing tendency for the atmospheric circulation itself to strengthen under reduced radiative forcing (7).
Now, consider this finding in light of Figure 1. Yes, it is a simple “thermostat” in the sense that as the equator heats up, the area around 30°N/S cools.
But in the light of the climate heat engine it is much more than that. The Constructal Law says in response to increased forcing the climate system will respond by increasing throughput. One way to increase the throughput of a closed cycle heat engine is to cool the radiator.
And that is exactly what their “ocean dynamical thermostat” is doing. By cooling the radiator of the climate heat engine, the engine runs faster, and moves more heat from the tropics. Conversely, when the earth is cooler than usual, the engine runs slower, and less heat is transported from the tropics. This warms the tropics.
I started this by saying that I would provide a theoretical framework within which the Lauer10 findings would make sense. I believe I have done so. My theoretical results were strengthened by my subsequent finding that Marchitto et al. fits the same framework. However, this is only my understanding. Additions, subtractions, questions, falsifications, confusions, expansions, and just about anything but conflagrations gratefully accepted.
Finally, testable predictions lie at the heart of science, and they are scarce in climate science. If I am correct, the kind of study done by Lauer et al. of the persistent stratocumulus decks in e.g. the Eastern Pacific should reveal that in the observations, changes in night-time cloud cover are greater than changes in day-time cloud cover. My check from the Koch brothers must have gotten lost in the mail, so I don’t have the resources for such a study, but that is a testable prediction. It would certainly be a good and very easy direction for Lauer et al. to investigate, they have the records in hand. Here’s their chance to prove me wrong …
My regards to all,
w.
References and Notes for the above quotations from Marchitto et al.
3. M. E. Mann, M. A. Cane, S. E. Zebiak, A. Clement, J. Clim. 18, 447 (2005).
4. A. C. Clement, R. Seager, M. A. Cane, S. E. Zebiak, J. Clim. 9, 2190 (1996).
5. K. M. Cobb, C. D. Charles, H. Cheng, R. L. Edwards, Nature 424, 271 (2003).
6. M. E. Mann et al., Science 326, 1256 (2009).
7. G. A. Vecchi, A. Clement, B. J. Soden, Eos 89, 81 (2008).
PS – Both papers, one discussing the atmosphere and the other the ocean, explicitly note that this thermostatic effect is not correctly simulated by the climate models (GCMs). The Marchitto paper is very clear about exactly why. It is because of one of the most glaring and under-reported shortcomings of the models. Here’s Marchitto again, in case you didn’t catch it the first time through (emphasis mine):
In contrast, fully coupled general circulation models (GCMs) lack a robust thermostat response because of an opposing tendency for the atmospheric circulation itself to strengthen under reduced radiative forcing (7).
Say what? Model circulation strengthens under reduced forcing?
In a natural heat engine, when you add more heat, the heat engine speeds up. We can see this daily in the tropics. As the radiative forcing increases, more and more thunderstorms form, and the atmospheric circulation speeds up. It’s basic meteorology.
In the models, amazingly, as the radiative forcing increases, the atmospheric circulation actually slows down. I might have missed it, but I’ve never seen a modeller address this issue, and I’ve been looking for an explanation since the EOS paper came out. Although to be fair the modellers might have overlooked the problem, it’s far from the only elephant in the model room. But dang, it’s a big one, even among elephants.
So yeah, I can see why the models are missing the proper thermostatic feedback. If your model is so bad that modelled atmospheric circulation slows down when the forcing increases, anything’s possible.
“four doublings of CO2”. Is that 1+2+3+4 or 1+2+4+8 ?
Does this have anything in common to Lindzen’s Infrared Iris Effect?
Willis I humbly submit that you are WRONG,
That’s a mammoth in the room.
Thank you Willis, our robust self regulating heat source refrigerator with H2O as a refrigerant will confound the AGW crowd. The winter in the north and the summer in the south shows a profound connection to the antics of our heat source Sol.
That is a superb post Willis.
Living in outback Western Australia between 26-27S we have always known that we were is a sort of no mans land.
Too far south to get the regular summer rains and too far north to get the regular winter rains.
I have a new project – correlate solar activity to temperature and rainfall in summer and winter and see if there is an apparent connection.
Well written clear and precise article. Good that you emphasise the differing effects of stratocumulus by day and by night, something which seems to be missing in GCMs.
Can the modellers really believe that atmos. circulation slows down with increased radiative forcing? Extraordinary!
So much common sense in this article, and well written, I hope you will find the funding to take your ideas further
@Grumpy old Man
four doublings are 2*2*2*2=16
OK Willis, That’s the Hadley Cell sorted. Now go for the jugular and show how this impacts on the activity and organisation of the Ferrel Cell (and consequential linkage to the Polar Cell).
Now that would be a study worthy of a humongous grant!
Terrific piece, Willis – clear as day. I hope the prediction of your hypothesis does get tested.
Lauer et al. provide observational data that shows in the last two decade time period there is a reduction in marine clouds that accompanies an increase in the ocean surface temperature for latitudes around 30 degrees.
The question is cause or effect? (i.e. Did something else causing the reduction in planetary cloud during the same period? If something else caused a reduction in planetary cloud cover, then the reduction in planetary cloud cover would cause a significant portion of the observed warming during this same period, thereby confusing the issue as to the magnitude of warming due to CO2 increases and confusing the issue as to whether there is an increase or decrease in planetary cloud cover when planetary temperature increases.
The something else hypothesis explains why there was no observed CO2 warming prior to around 1985. The solar magnetic cycle appears to now be interrupted so there should be observational data to prove or disprove the competing hypotheses over the next 5 years.
http://www.probeinternational.org/Livingston-penn-2010.pdf
During the same period of time (last couple of decades) there has been an increase in solar wind bursts, particularly at the end of solar cycles at which time GCR is high. The solar wind bursts remove cloud forming ions via a process called electroscavenging at latitudes between 30 degree to 60 degree (A space charge differential is created in the ionosphere by the solar wind bursts. The space charge differential removes the cloud forming ions. The atmosphere above the oceans is ion poor. The GCR cloud modulation effects are less over the continents as there are ions generated over the continents by radioactive elements in the continental crust. i.e. The atmosphere above the oceans is ion poor without the additional ions that are generated by galactic cosmic ray GCR high energy particles (mostly protons) that strike the upper atmosphere creating MUONs (heavy electrons). The MUONs that travel through the atmosphere creating multiple ions. The effect is dependent on both the number and the velocity of the GCR particles that strike the earth’s upper atmosphere.
The electroscavenging effect makes it appear that planetary cloud cover and planetary albedo (the albedo of the clouds change in addition to the area of cloud cover due to an increase or decrease in ions.) are not modulated by GCR. (GCR is in turn modulated by the strength and the extent of the solar heliosphere. The solar heliosphere is the name for the pieces of the solar magnetic field that are pushed of into space by the solar wind. The strength and extent of the solar heliosphere determines how many GCR particles and the velocity of the GCR that strikes the earth’s atmosphere.
http://sait.oat.ts.astro.it/MSAIt760405/PDF/2005MmSAI..76..969G.pdf
“Once again about global warming and solar activity K. Georgieva, C. Bianchi, and B. Kirov
We show that the index commonly used for quantifying long-term changes in solar activity, the sunspot number, accounts for only one part of solar activity and using this index leads to the underestimation of the role of solar activity in the global warming in the recent decades. A more suitable index is the geomagnetic activity which reflects all solar activity, and it is highly correlated to global temperature variations in the whole period for which we have data.
In Figure 6 the long-term variations in global temperature are compared to the long-term variations in geomagnetic activity as expressed by the ak-index (Nevanlinna and Kataja 2003). The correlation between the two quantities is 0.85 with p<0.01 for the whole period studied.It could therefore be concluded that both the decreasing correlation between sunspot number and geomagnetic activity, and the deviation of the global temperature long-term trend from solar activity as expressed by sunspot index are due to the increased number of high-speed streams of
solar wind on the declining phase and in the minimum of sunspot cycle in the last decades."
http://www.agu.org/pubs/crossref/2009/2009JA014342.shtml
"If the Sun is so quiet, why is the Earth ringing? A comparison of two solar minimum intervals.
Observations from the recent Whole Heliosphere Interval (WHI) solar minimum campaign are compared to last cycle's Whole Sun Month (WSM) to demonstrate that sunspot numbers, while providing a good measure of solar activity, do not provide sufficient information to gauge solar and heliospheric magnetic complexity and its effect at the Earth."
See section 5a) Modulation of the global circuit in this review paper, by solar wind burst and the process electroscavenging where by increases in the global electric circuit remove cloud forming ions.
The same review paper summarizes the data that does show correlation between low level clouds and GCR.
http://www.utdallas.edu/physics/pdf/Atmos_060302.pdf
From the post by Willis:
“Reduced cloudiness at the cold end of the heat engine is an expected change in this regard, just as we expect (and find) increased cloudiness at the hot end of the heat engine with increasing heat.”
Willis, the increased cloudiness at the hot end only adds to your excellent writing. As this is day time afternoon cloudiness, the effect of additional clouds here is strongly cooling to the surface, and in particular to the three dimensional very large heat capacity of the ocean, which heats primarily through SWR. At the tropics in the afternoon this incoming solar insolation is closer to 1,000 W/m2, and any reduction in SWR entering the ocean here is critical. You are quite correct to state that “when” something happens is a very cogent factor in its effect. The following quote from your post on “how Long: an effect persists is critical as well.
“It is the long-term balance of these flows across the ocean surface that determines the oceanic (and therefore the atmospheric) temperature. As a result, small sustained imbalances can cause gradual temperature shifts of the entire system.”
This very critical to understanding earth’s energy budget. The larger any systems heat capacity, the more energy it can lose or gain in any persistent change in input. A systems heat capacity is also a function of time. The longer any given input can stay within a system, the greater its heat capacity. On earth our oceans contain up to 1000 times more energy then the atmosphere. Any change in input to the oceans will overtime far out weigh the same change in input or residence time to the atmosphere as the following simple traffic illustration displays.
1. On a highway if ten cars per hour enter the highway, and the cars are on the road for ten hours before exiting, there will be 100 cars on the road and as long as these factors remain the same the system is in balance. If you change the INPUT to eleven cars per hour, then over a ten hour period the system will increase from 100 cars to 110 cars before a balance is restored and no further increase occurs. The same effect as the increase in INPUT achieves can be realized by either slowing the cars down 10% or by lengthening the road 10%. In either case you have increased the energy in the system by ten percent by either increasing the residence time or the input.
2. Now lets us take the case of a very slow or long road with the same input. Ten cars per hour input, 1000 hours on the road, now you have ten thousand cars on the road. Now lets us increase the input to eleven cars per hour just as we did on the road with a ten hour residence time. Over a 1,000 hour period we have the same 10% increase in cars (energy) How ever, due to the greater capacity on that road, the cars (energy) have increased 100 times relative to the 10 hour road with a 10% increase in input. (1,000 car increase verses a 10 car increase.) Any change in the input or the residence time on this 1,000 hour road will have a 100 times greater effect then on the 10 hour road if the input change endures for 1,000 hours. The ocean of course is the 1000 hour road, the atmosphere is the 10 hour road.
Outstanding Willis! This analysis is one of your best written ones yet, crystal clear and exceptionally easy to follow. It drips with common sense and I love that. Having lived all my life between 18 and 27 degrees North I can attest to your explanations fitting a lifetime of my observations. Thank You!
Regards,
Jose
As for the lack of ability for GCM’s to describe the thermostat effect, there should be important defects. My gut feeling is that one of those defects is the assumption of constant relative humidity.
Grumpy Old Man>
Neither. It’s 1*2 = 2 => 2*2 = 4 => 4*2 = 8 => 8*2=16
“In short, their study reports that when the ocean gets warmer at the equator, it gets cooler at 30°N, and vice versa. They also find that this effect is visible on annual through millennial timescales. Unsurprisingly, this is not found in the GCMs.”
Should look at this monthly in comparison to land temperature deviations, that would help to define the ENSO function.
I see the circus at Cancun has ended with what is being hailed as an agreement. Lookinmg forward to an analysis of what idiocy has this bunch of nut jobs committed us to.
Seems like even a couple hours between data points is too coarse a resolution to model diurnal cloud changes in GCMs. Are those parameterized? If so, do they change the parameters to account for warming?
To amplify William’s point, the solar wind is linked to the Earth’s geomagnetic indices, especially Dst.
http://tallbloke.wordpress.com/2010/11/24/earths-magnetic-field-mimics-solar-activity/
This was covered in a WUWT post recently that Leif, Vuk and I were active on. The Dst index is measuring the ring current which circles the Earth high up in the atmosphere. Geomagnetic storms caused by solar activity induce extra current and this changes ionisation in the atmosphere, which affects cloud condensation nuclei production rates.
This is a way the sun’s activity affects climate which is not measured by changes in TSI alone, and could be part of the amplification mechanism described by Nir Shaviv in his JGR paper ‘Using the oceans as a calorimeter’.
http://sciencebits.com/calorimeter
This mechanism may be complementary to the Svensmark hypothesis.
Erl Happ has recently been doing extensive work in this area and has determine a link between Dst changes and ENSO. I hope he finds the time to comment here, but here’s a quick summary:
“In brief, change in the differential pressure that drives the Westerly winds in winter in both hemispheres is coincidental with warming of the upper troposphere in the mid and low latitudes that, my logic suggests, will reduce cloud cover. At any rate there is an observable increase in Sea Surface temperature that is coincident and coextensive.
The change in the pressure relations that we associate with the AAO index and the AO index that is responsible for the increase in the differential pressure driving the westerlies and coincident with upper troposphere warming (and associated cloud loss) is associated with fluctuation in the solar wind as measured in the Dst index. And that is the driver of ENSO and also the warming and cooling of the globe on longer time scales.
Energetically, negative Dst is associated with a fall in sea surface pressure at the poles.”
I have looked at the Pacific Ocean (mainly North) and found five critical elements, not all geographic, which I think may have profound impact on the Pacific oscillations. They are all based on reliable data of physical events not considered to be related to the climate.
Two out of five have already produced important results as shown here:
http://www.vukcevic.talktalk.net/NPG.htm
Enneagram says: December 9, 2010 at 5:11 am
What do you mean by Gateway?
…………..
My neighbours have one of those remotely controlled electric gates, for way in and out.
No conflict there with sun etc.
Ian H says:
December 11, 2010 at 5:49 am
“I see the circus at Cancun has ended with what is being hailed as an agreement. Lookinmg forward to an analysis of what idiocy has this bunch of nut jobs committed us to.”
They have agreed on trying to agree next year in SA.
I have been thinking about the ways that GCRs might modulate feedback. The hypothesis is that GCR effects do not necessarily translate into warming or cooling (i.e. be quantified productively as a forcing), but rather the way weather responds to other forcings such as solar TSI and CO2 increases. Those changes can include the cloud changes mentioned above but also the blocking shown in http://www.appmath.columbia.edu/ssws/index.php
I’ve been trying to get some feedback at http://www.skepticalscience.com/cosmic-rays-and-global-warming.htm without much luck so far. It seems to me that essential link from GCR to climate is that GCR modulates the weather in general and clouds in particular. The thread above shows how clouds modulate the heat engine and I would posit that GCR modulates the heat engine thereby adding damping or amplification to warming from any forcing. For example, the slight but steady warming from CO2 can be amplified or damped by the heat engine but the heat engine is modulated by GCRs.
Likewise for studies of past interglacial warming, the missing element seems to be the modulation of feedback controls like the heat engine. The last interglacial before the present one showed an abrupt decrease in GCR:
http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/WhatsNew.pdf The article of course is intended to dismiss all GCR effects by analyzing them as forcings and not as a modulator of weather. Anyway that abrupt decrease coincides with the rapid warming in the interglacial. I would maintain that the rapid warming caused by an amplification of solar forcing (along with the NH albedo decreases and other Milankovitch cycle factors).
It also seems likely that late 20th century GCR decreases helped warming (natural TSI and anthro CO2 forced).
Beautiful logic, Willis, thanks!
I have posted the following rant yesterday on notrickszone, but i’d like to repost it here because it might help explain the obnoxious attitude of AGW climatologists:
Why do climatologists hate new evidence-based discoveries? They hate it; they fight it, they try to rebut it as far as they can. Why? This is completely contradicting the behaviour in other scientific fields.
The reason is: Every time a new mechanism gets discovered they would have to rework their computer programs to take it into account – imagine, just after you made your complicated GCM hindcast the past correctly, and you had to find the exact right combination of 20 parameters to have the best curve fit, comes some post doc scientist with a study that proves the influence of, say, cosmic rays.
You have to make it go away, or you would have to start from scratch with your huge computer model all over again!
They are simply red-queened; they lose ground even while running under the shifting sands of knowledge… Their GCMs are their own maintenance nightmare, and they must suppress all new science because they need to perfect their beautiful mechanisms!
(I had the Svensmark hypothesis in mind when writing it; but it’s equally true for the stunning fact that the circulation in GCM’s slows down when more energy comes in. Fixing it in the models would probably mean a major rework.)
I should mention that the specific problem with the “What’s New Under the Sun” paper is that they use GCR proxies as an indicator of solar activity, then translate solar activity to relatively small changes in TSI, then dismiss it. That is backwards, IMO, the GCRs are the main effect modulating weather in the way described in this thread.
Philip Mulholland says:
December 11, 2010 at 4:44 am
OK Willis, That’s the Hadley Cell sorted. Now go for the jugular and show how this impacts on the activity and organisation of the Ferrel Cell (and consequential linkage to the Polar Cell).
I had a go at both Hadley and Polar. Ferrel is ‘piggy in the middle’ it has a bite of each.
http://www.vukcevic.talktalk.net/LFC20.htm
http://www.vukcevic.talktalk.net/NFC1.htm
Willis: “But what they are neglecting is that the ocean is no longer receiving 370 W/m2 of LW from the cloud. Instead, above the ocean is mostly dry air, which provides little downwelling radiation to the surface. In this case the surface itself is losing about 400 W/m2.”
The downwelling radiation going from 370 to near zero seems way too much. Shouldn’t dry air still produce near 1/2 the original 370 W/m2 downwelling radiation?
Excellent post
What I would like to see added to the mix is surface ocean currents, specifically how they transport water from under cloudy areas to cloud free areas throughout the day and night. However, I think it would be asking too much for anyone to figure that out.
I wonder whether there could be a simpler explanation.
If a more active sun causes the polar vortex to shrink as it did during the late 20th century waming spell then the mid latitude jets and their clouds shift poleward with a consequent reduction in total cloudiness and albedo.
More sunlight then gets into the oceans in the tropics and subtropics.
The extra energy input then stimulates convective uplift along the ITCZ which then increases the intensity, width and latitudinal position of the subtropical high pressure cells as the uplifted air descends again.
With more downward airflow into the subtropical highs the low stratocumulus would tend to evaporate and/or move poleward and so be pushed further beyond 30 degrees latitude thus taking some of it out of the region being considered and possibly decreasing total stratocumulus globally.
I seem to recall lots of historical evidence that the desert belts and all the other air circulation systems do drift latitudinally over time on a similar timescale to that between MWP, LIA and the current warm period. Lots of civilisations have come and gone as a result of such changes.
There is a see-saw effect. Tropical thunderstorms efficiently move heat into the upper atmosphere, but then the descending dry air kills off the surface clouds, causing sea surface warming and reversing the cycle. This confuses the issue for anyone looking for a steady-state effect.
In reply to Steve Reynolds:
You’re right, dry air still would supply a significant amount of back radiation.
“Science of Doom” gives some actual charts of 24 hr back radiation on this post:
http://scienceofdoom.com/2010/07/17/the-amazing-case-of-back-radiation/
http://scienceofdoom.files.wordpress.com/2010/07/dlr-billings-ok-1993-3days.png
This is a masterful bit of work. We have all had massive problems with GCM’s. I can remember huge ranker do to the poor representations of things, right from the beginning. Now another major short coming. In addition to that we know the models do not deal well with the area, as well as the timing. Take all three problems and it adds up to nothing but blind speculation.
Remember, keep a skeptical eye and remember Mother Nature plays with loaded dice.
It would be most interesting to read Dr Spencer’s views on the cloud issue, particularly with regard to cause and effect.
Grumpy old Man says:
December 11, 2010 at 3:13 am
“four doublings of CO2″. Is that 1+2+3+4 or 1+2+4+8 ?
Moritz Petersen says:
December 11, 2010 at 4:36 am
@Grumpy old Man
four doublings are 2*2*2*2=16
Dave says:
December 11, 2010 at 5:46 am
Grumpy Old Man>
Neither. It’s 1*2 = 2 => 2*2 = 4 => 4*2 = 8 => 8*2=16
HARRY_READ_ME
Four doublings? Four doublings would be 0001 0000.
Wow! What a great article. Having received my engineering education 50 years ago, and retiring 10 years ago, I had never heard of constructal theory or constructal law. After checking out your references (and others), I am really excited. And as a mechanical engineer, the comparison to a heat engine really made sense.
Since the early ’90s I have been reading articles that climate models don’t handle clouds correctly. If I understand what you are saying correctly, cloud effects vary with time and location. Averaging of these effects in the GCM’s is one of the causes of their incorrect results.
Some organization that is interested in getting at a real predictor of climate (not sure that is possible) should certainly fund a study using constructal theory, and that puts time of day and spacial location into the grids of the GCM.
Also looking at the atmosphere as a heat engine with the sun as the source of the heat, is going to make me pay more attention the those who keep saying “It’s the sun, stupid.”
A very pretty argument.
May I mention a ‘typo’ in the para beginning ‘I found this doubtful for a number of reasons. First…’ Where you write ‘This puts the cloud base at around five degrees C cooler than the surface.’ I believe that this should be ‘warmer’ rather than ‘cooler’. You have it correct at the end of the paragraph.
But thanks for an excellent exposition.
Exceptional article, thanks for posting this and taking the time to present the Climate System Heat Engine as a dynamic!
Kelvin waves, the Coriolis effect, ratio of ocean to land mass in the NH and SH, currents, wind patterns, time of year, weather patterns like Hurricanes, etc. add interesting regional aspects to the tropical cloud cover and “Global” dynamic.
Its a real shame you aren’t one of the lead AR5 contributors. They intend to attempt to account for clouds in AR5.
This is something I have been considering for a while, that it is entirely possible that when something gets hotter in one area, another area gets that much cooler. Which is why averaging to a global temperature can hide regional weather pattern variation change and even climate change to an ice age or out of one.
Doublings?
Where do you start? What’s with the 1s, 2s, and so on.
If you start at about 270 ppm of our favorite gas, then
the 1st doubling gets you to 540 ppm;
the 2nd doubling gets you to 1080 ppm;
the 3rd doubling gets you to 2160 ppm;
the 4th doubling gets you to 4320 ppm;
I’m still wondering how we manage to make that first doubling happen?
Anyone seriously interested in the Pacific should take a good look at graph No.4 in
http://www.vukcevic.talktalk.net/NPG.htm
There is no doubt that the ‘magenta gateway’ got control of the PDO.
Willis, you are very clever young man, but it is mechanisms all the way down!
That is, why are there less stratocumulus clouds at the places mentioned when the atmosphere heats up.
Given that the atmosphere contains approximately 1000 times less energy than the oceans it seems inconceivable (and I do know what that word means) that the atmosphere is driving the oceans. However, clouds can only form when there is moisture in the atmosphere, which comes from the evaporation of water from the oceans and other bodies, or from evapotranspiration from plants.
Show me the mechanism!
Willis carefully avoids estimating solar effects in comparison with longwave effects. Had he done so, he would see that the solar impact of adding (or subtracting) low clouds is cooling (or warming) an order of magnitude larger than the 30 W/m2 he is concerning himself with. For example several hundred W/m2 of solar radiation don’t get to the ocean when a cloud is there, which outweighs the longwave cooling effect. The effect of low-cloud coverage is recognized to be a major component in the climate system due to its strong cooling effect with increasing coverage. If its effect is decreasing with warming, one of the last major hopes of the skeptics is removed, which is why this paper is so interesting, and bound to become a target for further investigation.
Jim D says:
December 11, 2010 at 9:57 am
Actually, he explicitly spoke about what occurs with cloud related albedo and solar effects, pointing out (correctly) that it is more to do with the timing of the cloud formation and cover.
The relevant difference between stratocumulus at 30° latitude and the equatorial clouds is that the equatorial clouds die out and vanish at night. This allows for free radiation from the surface. The stratocumulus deck, on the other hand, persists day and night. This means that it has much more effect on radiation than equatorial cloud.
This is exactly where he said further study is needed, looking at the formation and duration of stratocumulus clouds with increased temps. His theory is that they’ll decrease in amount, allowing more upwelling radiation without the blocked back downwelling radiation. Conversely, in a cooler system, the heat engine would slow, the amount of cloud cover in the 30th would increase, keeping heat in at the 30th (where it would normally be lost, as opposed to the net tropical gain) The system would begin to reheat and turn back around.
Several things become apparent in this system. Warm moist air from the tropics exposed to colder conditions will be more likely to form clouds, as the water vapor will more easily condense. Conversely, less condensation can occur with warmer temps. Since the low level clouds are at their height only about 6 deg off of the surface temps, it’s extremely easy for oceanic temperatures to play a role in determining maritime stratocumulus development. Warmer ocean leads to less clouds leads to increased radiation to space, leads to cooling, leads to more clouds, leads to warming, leads to less clouds…. cyclical, comprised of a strong negative feedback mechanism working towards a stable equilibrium, but cyclically oscillating around that equilibrium due to the smaller positive feedbacks.
As Willis said. They have the records, all they have to do is examine them to prove him right or wrong. Bring it on, I say, and share the data so we plebs can play along.
BTW, Willis, if something I said was wrong, please correct me, but it’s exactly what I inferenced from a studied read of the post.
Richard Sharpe… apparently I also answered your question. The mechanism for the decreased cloud cover with warmer temperatures is the higher water vapor carrying capacity.
Simple as I can explain it. Tropics heat up, transfer MORE energy to the temperate and polar zones. As the tropics get warmer, the heat engine moves faster, transferring the heat more quickly. So the temperatures at the temperate regions would be higher, meaning a higher water vapor carrying capacity of the air at the 30th. Higher water vapor carrying capacity means less condensation, means less clouds. Lower temps in the tropics lead to less transfer of heat, the air has more time to cool on the way, and hence more of the water vapor condenses out to be carried poleward, increasing cloud cover.
Approximately right?
Willis, you correctly criticized the process of averaging. But you have in your article:
In this passage it seems that you’ve averaged over seasons — in the [local] summertime, the insolation at 30° latitude should be close to the equatorial value, while the winter ratio is probably less than the 60% you mention.
As far as I could tell from a brief scan of Lauer10, the paper does not break out cloud cover by season, although they do seem to have monthly values available. Could you please comment on whether seasonal insolation variation makes any difference to your overall argument? And more importantly, what do the satellite observations say about seasonal cloud cover, vs. averaged?
Jim D says:
December 11, 2010 at 9:57 am
Jim D., first, your comments on my motives (“Willis carefully avoids estimating…”) are nasty and unwarranted.
Second, I expressly discussed and estimated the amount of solar forcing in the area. At maximum it is about 60% of the equatorial solar forcing.
Third, this is why I said that night-time changes would be greater than day-time changes.
So you are not only wrong. You are unpleasantly wrong. This is a very bad combination if you are trying to get any traction here …
Jim D says:
December 11, 2010 at 9:57 am
“one of the last major hopes of skeptics.”
Too funny.
There are 3 GW’s of windmills on the Bonneville Power Grid, not one of them is generating any electricity at the moment. Current score on the BPA grid – Coal 3 GW, Nuclear 1 GW, Wind 0
The books of Marcel LeRoux are interesting. He doesn’t substantiate his postulates with so much as a lick of physics. There are some obvious errors ( in that momentum peaks well above the surface, yet his focus is on surface ‘Mobile Polar Highs’).
And yet I think LeRoux was right about some important aspects that have been glossed over for a century or more of meteorological thought. Namely, polar air mass motions account for two features I believe are wrongly ascribed above.
Those features are 1.) the subtropical deserts and 2.)the equatorial convection.
1. The subtropical deserts fit very well with the concept that polar air masses tend to modify and lose momentum the farther they move from their origin. The mythical
‘Hadley Cells’ represent just a statistical average of air mass pathways. Polar air masses move equatorward but in the process tend to elongate, stall, and accumulate,
especially on the eastern edges of the oceans where the potential energy is at a minimum ( because the mass is at sea level )
2. The ITCZ, in this line of thinking, is not, as indicated above, a result of increased thermal load, but rather a result of the converging polar air masses. This is evident when one observes the ITCZ ( the inter-tropical convergence zone). The ITCZ is much narrower than the area of tropical heat. Further, in the Eastern Pacific, the ITCZ remains north of the equator year round and does not follow the solar loading. I have the benefit of watching animations of precipitable water from the GFS model over a number of days. Watching these animations, it is quite easy to identify polar air masses as they form, traverse the mid-latitudes, elongate, and eventually become easterly waves in the tropical circulation.
Appreciation of the general circulation leads me to believe there’s little ground to make any pronouncements on how circulation might change, if at all, due to CO2.
But watching the general circulation also makes me appreciate that the main constraints of climate are: pole to equator insolation difference, the orientation of the oceans, the orientation of the mountains, and the rotation of the earth. These things aren’t going to change much.
An interesting theory, however I believe your original premise about stratiform clouds is generally incorrect unless I have mistaken your meaning.
You say:
“First, the cloud top for marine stratiform clouds is typically at an altitude of ~600-700 metres, and the cloud bottom is at around 400-500 metres. The dry adiabatic lapse rate (cooling with increasing altitude in dry air) is about 1°C per hundred metres. This puts the cloud base at around five degrees C cooler than the surface. Then we have 200 metres at the wet adiabatic lapse rate, that’s about another degree. Total of six degrees cooler at the cloud tops.”
Stratiform clouds do not generally form due to adiabatic cooling as is the case with convective clouds. Stratiform clouds form under an almost opposite atmospheric profile from convective clouds. The air above a deck of stratiform clouds is generally subsiding and forms an inversion. Moisture below this inversion is then trapped and, as the airmass saturates, clouds form. The temperature profile below the cloud top is either isothermal or even slightly warmer at the cloud top than below. You can see an example of this in radiosonde soundings along the coast of California. I looked at the sounding for San Diego today (NKX) through the Wyoming weather site http://weather.uwyo.edu/upperair/sounding.html. It shows a typical marine stratum profile with a saturated low layer and an almost isothermal layer to about 750 mb. Certainly there is no adiabatic temperature profile in the low stratus layer. In Canada we are often plagued with large areas of stratus in the fall when there is still lots of low level moisture available and warmer air sits over a cool layer. These conditions can persist for long periods of time. I hope this helpful.
Jim D says:
December 11, 2010 at 9:57 am
If its effect is decreasing with warming, one of the last major hopes of the skeptics is removed, which is why this paper is so interesting, and bound to become a target for further investigation.
Of coarse it will become a target. You will see alarmists cranking out paper after paper showing how an increase in temp reduces the cooling effect of clouds and so they will claim their models are correct in having clouds as a positive feedback. They will only study the areas like at 30 deg where clouds act as a radiator and gleefully say that all clouds work in a similar fasion. They are not looking for the whole picture, they are looking to prove why their models are correct.
thanks Willis. This is great stuff, as usual,
I think you are the greatest climate realist, but as in any hockey game,
it will take some time to tell…
Something else:
if you study the pattern of modern warming, for example, here, we have some average temperature data since 1946,
http://img502.imageshack.us/img502/8705/navacerrada.gif
Spain is pretty much average as avarage goes for a place to stay on earth! The station has been very accurate in its recordings and apparently only one day’s recordings are missing. Note that the average minimum temps. since 1980 have stayed constant. If green house gasses were to blame for the warming (the trapping of heat), you would think that it should have been minimum temps that would show the increase (of modern warming). But that line is completely straight…..So it cannot be greenhouse gasses that caused modern warming.
I just wonder if any of you might have some other similar data that confirms what they have found here in Spain (I will look for same data myself in South Africa as well when I get some time)
Willis, I mentioned it as the elephant in the room. I still see no quantification of its relative effect in your response, and was surprised it had not been quantified in the post. How can a post on low clouds not deal with the hundreds of W/m2 that form part of the budget that is actually more important than what you were talking about. Instead of careful avoidance, I might have said “ignored” or “forgotten about” or “disregarded” or simply “chose not to talk about”, which may be construed with various degrees of nastiness, but those were the words that came to mind based on some prejudice/bias I perceived from the post. I have this idealized view, perhaps, of science informational posts being neutral and well balanced which helps people to form opinions more correctly. If big chunks of highly relevant information are missing it can look biased to those who know about the missing pieces of the puzzle.
Willis – my impression is that Lauer and you both make the same mistake as the IPCC. The IPCC only ever considers clouds to react to climate (“feedback”). It never contemplates the idea that clouds are a driver of climate (other than to dismiss Svensmark with a handwave). Like the IPCC, when Lauer says “some marine stratocumulus clouds decrease with increasing warming“, he does not consider the possibility that the warming is caused by decreased clouds.
Others have made this point already, but I thought it worth expressing it more briefly.
Here’s a nice global map of outgoing LWR. Supports your thesis quite nicely.
http://www.iapmw.unibe.ch/research/projects/FriOWL/docs/chapter6_4_olr_final.pdf
Mike Jonas says:
December 11, 2010 at 12:20 pm
…………..
Attempts to explain climate change with a product of a climate change will fall by the wayside. Even the CO2 seesaw (Vostok ice cores) appears to be caused by the climate change.
Solution is to be found outside the loop ‘cause-consequence-cause’.
An excellent post, thanks. I seems so obvious to me and it ties in with the world around me and how it works. How anyone can think warming will reduce global cloud cover creating more warming is detached from reality, if the climate really were that sensitive it would have already happened along time ago and we wouldnt be here talking about it!
I believe the climate models in order to reduce cloud cover with warming, have to reduce evaporation in the future (i.e. make earth drier), thats hard as its warmer, so wind shear is reduced significantly to justify such a response (we call it a “fudge” in modelling terms). I suspect the fudge used to force reduced could cover with warming would also work backwards, where cooling results in increased wind shear, and the climate system speeds up – despite there being less energy.
Huh, I believe I saw something back over there. So it is then that way.
In the referenced paper, http://www.iapmw.unibe.ch/research/projects/FriOWL/docs/chapter6_4_olr_final.pdf , there is a table that shows the global correlation between medium height clouds and outgoing LWR as -0.56. I believe those are the sort of clouds to which you refer. It would be interesting to see the correlation over deserts.
Table 6.4.1 shows the correlation between medium height clouds and outgoing LWR to be -0.56. I believe those are the clouds you were discussion WRT deserts. It would be interesting to see the correlation for just desert latitudes.
moderator: Sorry, I didn’t see the first post and posted a second time.
Hi Willis,
For sure increasing heat input in the tropics (or equivalently, decreasing heat loss in the tropics) should cause the ‘engine’ to run faster, but I think it would run faster because of a larger difference in temperature between warm source and cold sink. For the greater heat flow to be lost to space near 30 degrees north and south, there would seem to be a need for a somewhat warmer cold sink, which would lead to greater radiative heat loss to space. So, if the Hadley circulation is increased by tropical warming (more thunderstorms, etc.), then would the temperature not have to increase a bit near 30 degrees north and south to shed the greater heat flux?
Willis: Great article. I truly believe your “heat engine” concept is a key determinant of global climate. Now as to the waxing and waning of the mid-latitude stratocumulus decks, my thinking is similar to:
Stephen Wilde (who) says:
December 11, 2010 at 7:56 am
“…The extra energy input then stimulates convective uplift along the ITCZ which then increases the intensity, width and latitudinal position of the subtropical high pressure cells as the uplifted air descends again.
With more downward airflow into the subtropical highs the low stratocumulus would tend to evaporate and/or move poleward and so be pushed further beyond 30 degrees latitude thus taking some of it out of the region being considered and possibly decreasing total stratocumulus globally….”
That is, the increased flow of dry air in the descending portion of the Hadley Cell begins to reduce the moisture content in the cloud belts, so that the clouds dissipate. Similarly, the desert land areas should show some effects, as in becoming more desiccated or expanding, most likely in the direction of the equator, since the flux of dry air is moving in that direction. (That’s possibly part of the issue in the Sahel, isn’t it?).
This seems consistent with your discussion of the length of rivers and the Constructal Law, which I interpret happening because a shortening in river length in some area eventually results in water in the upper reaches of the stream moving faster. The water is continuous. Here, the air moved by the Hadley Cell is the continuum.
Hope I’m not a crackpot!
I don’t understand the impact of cooling the ocean (clear sky) compared with cooling the cloud tops (cloudy sky). In both cases the planet is cooled subject to subsequent energy transfer rebalancings between surface and atmosphere.
It could be argued that cooling the ocean then reduces the radiative output from it.
Colder water decreases cloud formation because of lower levels of evaporation. Warmer waters increase cloud formation because of increased evaporation. Anyone with a cup of tea in their hands on this cold snowy day can attest to that. Hold your hand over the tea when it is still warm and your hand gets wet. Wait till your cup of tea is cold and then try that. It has been one of the tenants of AGW that increased long wave radiation heating of the ocean surface will increase evaporation thus cloud formation. Now they are saying that won’t happen?
Here we go again. If one paper says one thing and says it is proof of CO2 driven global warming, another paper comes out that refutes it, but then says the refutation is proof of CO2 driven global warming. Is this being done to cover their collective asses because past predictions of this or that effect are not coming to fruition?
The cloud discussions obscure the mechanics of a heat engine.
At the root is a very simple process.
Convection carries heat from the surface to a higher altitude, above the densest greenhouse gases, where it is efficiently radiated into space.
The process has kept earth inhabitable for millions of years.
Pamela Gray says:
You are making an argument as to why a warmer world has more water vapor in the atmosphere. However, your picture is too simplistic to figure out what is going to happen with clouds (CONDENSED water vapor) because, while warmer air means more evaporation, it also means a larger amount of water vapor can be present before reaching saturation. Most of the modeling and empirical evidence suggest that the increase in water vapor will be such that the relative humidity remains roughly constant, at least on a globally-averaged scale…making it not easily apparent how cloudiness will change.
And, where exactly is that tenet to be found?
No…It has been generally-agreed-upon that an increase in low-level-marine clouds with temperature would produce a negative feedback and that a decrease would produce a positive feedback. In fact, I think that your description of the way things work applies more to this post and the author than to the scientists holding the consensus view on AGW. In particular, I think that Willis has long-argued how clouds constitute a negative feedback because they tend to increase with evaporation and their shortwave cooling effects cause cooling. In this piece, he has turned things on their head and is saying, in essence, “Now that they have found cloudiness actually decreases with warming, I think this is a negative feedback too because the clouds will decrease the amount of outgoing longwave radiation (and forget about that shortwave incoming radiation).”
To be fair, I think Willis would probably argue that the difference is whether the clouds are at around 30deg latitude or are in the tropics. (Is that right, Willis?) But, cooler me skeptical.
This comment may be a bit off the subject but I am looking for answers, so…..
If it is correct that the generally accepted solar constant is one of 1368 W/m2 as a satellite measured yearly average then how come the “Incoming Solar Radiation” is 341.3 W/m² as in a “Global Energy Plan W/m²” posted earlier? (By the way all other plans of that ilk that I have ever seen show very similar values.)
If the “Solar Constant” of 1368 M/m², as measured by satellite, is a yearly average arriving at the top of the atmosphere then one only has to divide 1368 with 2 (to roughly account for day and night) to arrive at 684 W/m² as being the “Incoming Solar Radiation”.
The same way as radiation “does not stick it’s finger out to determine where it is cooler before it decides in which direction to radiate” neither does the Sun’s radiation look to see whether it is going to hit a globe or a flat disc. It hits the whole disc or the whole globe
Reflection and absorption rates will of course be different for the two different objects.
Let’s take a look at the moon’s temperatures as collected by NASA’s Diviner satellite:
“Data accumulated by Diviner during August and the first half of September indicate that equatorial and mid-latitude daytime temperatures are 224 degrees Fahrenheit, and then decrease sharply poleward of 70 degrees north latitude. Equatorial and mid-latitude nighttime temperatures are -298 degrees Fahrenheit, and then decrease poleward of 80 degrees north latitude. At low and mid-latitudes, there are isolated warmer regions with nighttime temperatures of -208 degrees Fahrenheit.”
If we look at the full moon here from Earth the curvature pole wards, on the Earth facing side, cannot be seen because there is no difference in solar irradiation. The sharp temperature decrease pole ward can only mean that an increase in curvature = an increase in irradiative deflection or reflection
How much heat/cold is exchanged due to conduction and radiation through the moon’s mass polewards from (70 – 80 ° N & S) is a different question.
Yikes! English is not a very phonetic language, Dennis. That’s “rancor” and “due to”, pliz. Your spell checker can’t pick up substituted homonyms!
As for the 3 major failings, the comment elsewhere about resisting new information that would require a rejigging of all the parameters to keep the GCMs within bounds relates to this; they are trying hard to keep the failings, as so much effort has been expended to protect them already. And more to come!
The heat pump that is planet Earth has two major differences to a heat actuated refrigerator. The atmosphere is our plumbing, unbounded thus somewhat chaotic.
The refrigerant H2O is in vast quantity acting as a heat bank and moderator, this gives lag times of some years before heat input changes take large effect on the temperature.
The new satellites monitoring our heat source will correlate to conditions on Earth over time , if the temperature record can be uncorrupted.
Weather satellite photos of Earth often show swirled spokes of cloud formations emanating from the tropics and heading north and south, in a mirror image pattern.
This alone is proof of Willis’s heat pump Earth.
Someone has to explain what the causes the difference in warm dry air masses and warm humid air masses. During summer here in Florida, we have days that humidity is high and clouds start to form around noon with thunderstorms to follow around 4 PM. Other days the temperature is 94F but the air is drier and no clouds form at all. These warm air masses with different humidity levels move in and out of the area due to wind direction. But what causes the difference in the first place?
I’m constantly fascinated by comments about marine layer from people who, by their statement content, have never tried to get a tan, or surf, or whatever on a Southern California beach in June.
The water in June is still cold enough to keep the air temperature low enough to maintain the low stratus clouds – neglecting the possibility of a Santa Ana condition. Only after insolation has raised the water temperature enough that the evaporation is occurring into sufficiently warm air does the “June Gloom” disappear. (To clarify this, the air and water temperatures must rise – air temps rise quicker – thus June Gloom).
Northern California is plagued with the marine layer in the summer. Fog rolling in over the hills of S.F. is a classic image in the summer in The Bay Area.
I agree with HaroldW, December 11, 2010 at 10:52 am that seasonal insolation values would seem to alter the heat engines ability to dissipate heat at the summer/winter solstice.
There is a big swing of double the Earth’s obliquity of 23.45 Deg at these times and would bring the 30Deg Hadley cell extreme closer to the poles, making the cell more efficient at heat dissipation, and, of course greatly adding to polar melt. Add them up and this gives the cell an edge at 53.45 N/S at the Solstices. The ‘sinking’ air at these extremes is correct as sinking air is a high pressure system, dry clear with little moisture, low pressure systems are the opposite.
Just eyeball a globe as I did, and see the dramatic change as the sun swings directly above the Tropic of Cancer to the Tropic of Capricorn.
O H Dahlsveen says on December 11, 2010 at 3:59 pm
Area of the disk that receives incoming solar radiation = pi * r^2, where r is the radius of the earth.
Total surface area of the earth = 4*pi*r^2 …
So, that averages out at 1/4 of the incoming TSI. Since the earth rotates reasonable quickly it seems like a reasonable approximation.
Re Richard Sharpe says:
December 11, 2010 at 9:45 am
Willis, you are very clever young man, but it is mechanisms all the way down!
That is, why are there less stratocumulus clouds at the places mentioned when the atmosphere heats up.
Given that the atmosphere contains approximately 1000 times less energy than the oceans it seems inconceivable (and I do know what that word means) that the atmosphere is driving the oceans. However, clouds can only form when there is moisture in the atmosphere, which comes from the evaporation of water from the oceans and other bodies, or from evapotranspiration from plants.
Show me the mechanism!”
Richard, what heats the oceans, LWIR or SWR? The primary mechanism that controls heating or cooling the oceans is SWR, the primary mechanism that contols how much SWR enters the ocean is cloud cover and location, now what are the primary mechanisms that controls cloud cover and location?
Joel Shore says:
December 11, 2010 at 3:54 pm
“Now that they have found cloudiness actually decreases with warming”
Joel this is not correct, they said clouds decrease at one latitude and increase at another, nowhere did they state total cloud cover decreases with an excellrated hydrologic cycle, and if they did they are incorrect.
You sort of answered yourself; air that has previously been stripped of moisture, generally coming off large land masses (continental US, e.g.) or which has just made it over a mountain range where it dumped water and snow, is often very dry, while air which has been mostly moving over tropical waters is warm and wet. Just watch the met maps for where the air has been recently!
For a famous/funny allusion suggested by the title:
In the Barnham and Baily animal tent, people were so fascinated they wandered around for hours — “this way to the monkeys”, “this way to the egrets”, etc., and B&B couldn’t make much money selling tickets with that slow turnover. So one of them had an idea, and set up a long, winding, mysterious-looking tunnel, and put a sign at its entrance, “This way to the Egress!”.
Patrons kept up a much steadier stream to the outside after that, greatly boosting ticket throughput. 😉
Doubly so, since ‘excellerated’ would be reel illiterate-speak for ‘accelerated’.
Excellent post, Willis.
As always, I struggle to follow along but I follow… like the Baco’s commercial dog who can’t read but wants the Baco’s nonetheless.
Chris
Norfolk, VA, USA
David says:
December 11, 2010 at 5:09 am
“Any change in the input or the residence time on this 1,000 hour road will have a 100 times greater effect then on the 10 hour road if the input change endures for 1,000 hours. The ocean of course is the 1000 hour road, the atmosphere is the 10 hour road.”
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Oh yeah. This is on point!
~Chris
DirkH says:
December 11, 2010 at 7:06 am
Why do climatologists hate new evidence-based discoveries? They hate it; they fight it, they try to rebut it as far as they can. Why? This is completely contradicting the behaviour in other scientific fields.
The reason is: Every time a new mechanism gets discovered they would have to rework their computer programs to take it into account – imagine, just after you made your complicated GCM hindcast the past correctly, and you had to find the exact right combination of 20 parameters to have the best curve fit, comes some post doc scientist with a study that proves the influence of, say, cosmic rays.
You have to make it go away, or you would have to start from scratch with your huge computer model all over again!
They are simply red-queened; they lose ground even while running under the shifting sands of knowledge… Their GCMs are their own maintenance nightmare, and they must suppress all new science because they need to perfect their beautiful mechanisms!
==========================
Reposted here for effect. Excellent!
“Next, there is a fundamental difference between equatorial clouds (cumulus and cumulonimbus) and the stratocumulus decks of the area at 30° latitude. This difference is ignored by the averaging, with which climate science is unfortunately rife.”
=======================================
This struck me as one of the most prescient statements in this post. And I get what Willis and others are driving at:
They may all be clouds. But they are very very different animals.
Upward motion regions, such as those that accompany certain phases of the Madden-Julian Oscillation as it slowly sloshes through the atmosphere across the globe, bring volatile formations such as cumulonimbus.
Stratocumulus, are tamer, gentler, more temperate beasts.
Both beasts can not be averaged together as having the same overall effect.
Chris
Norfolk, VA, USA
Another aspect of the heat engine and its ability to transport heat or radiate it to space, is the change in the depth of the “deep convection” as temperatures go up.
As heating increases thunder cells rise to higher altitudes (with colder cloud top temperatures). As such this would be another mechanism to “speed up” the energy flow. It is much easier to radiate energy to space from an altitude of 18 km in the tropic summer than it is from an altitude of 8-9 km at higher latitudes.
The coldest temperatures in the tropopause occur in the tropics not at the more polar latitudes. I think it would be reasonable to expect that radiant heat losses would increase along the entire length of the Hadley cell path at higher temperatures because the higher temperatures would push up the tropopause to higher elevations (closer to space) and the more energetic convection would push the circulation farther north on the cool end of the heat engine.
At these temperatures, significant amounts of heat energy are being transported not in the form or increased temperatures, but in the form of latent heat of fusion in ice crystals. Temperature by itself, does not fully describe the energy flow, you must also consider the energy capacity of the more humid air and the latent heat it carries in both liquid water droplets and ice crystals.
You need, temperature, humidity and altitude included in the discussion, and all three will change as the Hadley cells become more energetic.
http://www-das.uwyo.edu/~geerts/cwx/notes/chap01/tropo.html
Larry
It’s worth considering how those “coldest temperatures in the tropopause” in the topics are maintained. Far from being a passive buffer, the ‘pause must be the most active heat transport layer of the atmosphere.
MaxL says:
December 11, 2010 at 11:30 am
My apology for unclear writing. I didn’t mean that the clouds formed from adiabatic cooling. I meant that we could estimate the cloud top temperature via adiabatic cooling rates.
w.
HenryP says:
December 11, 2010 at 11:54 am
Thanks, Henry. See my post called “Congenital Climate Abnormalities” for a number of things that haven’t changed …
If the press release is anything to go by, the study is so narrowly framed that it hardly seems worth reading. However, the following comment rings crystal clear:
“…Lead author Axel Lauer at the International Pacific Research Center (IPRC) at UHM notes, “All the global climate models we analyzed have serious deficiencies in simulating the properties of clouds in present-day climate. It is unfortunate that the global models’ greatest weakness may be in the one aspect that is most critical for predicting the magnitude of global warming…”
Jim D says:
December 11, 2010 at 12:09 pm
I dealt with the issue specifically, citing the part of the paper that talks about solar versus longwave radiation. I discussed various issues regarding that radiation. I spoke about how the long term effects differ from the short term. I’m sorry if it was not what you wanted. But to accuse me of deliberately avoiding the issue is simply not true.
I’m still not clear what your point is. Perhaps you could give us the “matchbook version” (short enough to write on a matchbook cover) or the “elevator speech” (short enough to deliver on an elevator ride) that spells out your point.
Thanks,
w.
Willis: You predict that the Hadley circulation – which functions like a heat engine – will speed up if temperature increases. However, the amount of work that can be done by a heat engine depends on the difference between the high and low temperatures, not the high temperature alone. If 30 degN and/or 30 degS warm as much or more than the equator, then the Hadley circulation will remain unchanged or slow.
Richard Sharpe says:
December 11, 2010 at 9:45 am
I love doing what I do at WUWT, because people are always pushing me to learn more.
There’s a very interesting journal article here that discusses the formation of stratus clouds. On p. 2153 they talk about what factors determine which kind of clouds form.
They find that if the sea is cooler than the air, the solid horizon to horizon bank of stratus forms. But if the sea is warmer than the air, individual cumulus form, with areas of clear descending air between them.
This is an odd mechanism, which agrees with you about the crucial factor of the ocean temperature, and which may explain the apparent contradiction of less cloud cover when the ocean is warmer.
w.
Mike Jonas says:
December 11, 2010 at 12:20 pm
I have most assuredly considered the idea that clouds drive the warming, and I find it lacking a cause. If the clouds are driving the warming, what is driving the clouds?
Certainly cosmic rays could drive climate, and initial results certainly indicate they are a forcing. But the fact that clouds change in response to cosmic rays does not make clouds a forcing.
Clouds form in response to changes in temperature, evaporation, humidity, cosmic rays, insolation, and the like. In general, I see all of those as a feedback. It gets a bit more complex when we consider emergent phenomena, but that’s the overview.
In the clear air under stratocumulus the lapse rate is indeed close to dry adiabatic. To predict stratocumulus you just average the moisture in the layer below the subsidence inversion. If there is enough moisture these clouds are formed by mixing below the inversion. Mixing WILL result in close to adiabatic lapse rates.
The base of any cumulus clouds will be lower than the stratocu base. Ask any soaring pilot.
BRAVO Willis!
A wonderful posting… simply wonderful.
Totally agree with:
Climate is a Heat Engine.
Climate is a Heat Engine regulated by H2O.
Climate is a Heat Engine with a thermostat.
Climate averages hide a multitude of sins
A HUGE BRAVO for your Heat Engine graphic.
It is the first Energy Balance diagram I have seen that incorporates the horizontal energy flows! This technique is the correct way to understand the Global Heat Engine and the Global Energy Balance.
Willis (and everybody but MaxL),
we have to consider the meteorological reason why the stratocumulus deck is there, in the eastern part of the subtropical oceans.
The reason is, as you know, the inversion in the temperature vertical profile due to the hot equatorial air aloft descending, along the subtropical belt, down toward an ocean cooled by the cold water upwelled from the deep ocean.
In a hypothetical warmer world, with an enhanced convective activity along the Equator, the permanent subtropical highs would be stronger, feeding the equatorial activity with stronger winds. Acting this way, the cold upwelling in the eastern seas would also be enhanced.
I can’t understand how, in a real world, a stronger temperature inversion can host less stratocumulus clouds
But Willis; Can you tell us what is new here?
I mean; What is new in the world of metereology ? Surely they know this? How can they otherwise come up with predictions? Hadley cells, all that?
What is new, and what is known. Among metereologists versus the AGW “scientists”.
Here are 3 screen grabs of Unisys graphics from this morning.
http://i279.photobucket.com/albums/kk145/pochas_2008/GOESNHwatervapor.png
http://i279.photobucket.com/albums/kk145/pochas_2008/Unisystempanomalies.png
http://i279.photobucket.com/albums/kk145/pochas_2008/GoesNHvisible.png
In the water vapor graphic, note the areas of the Caribbean and southeast of the Lesser Antilles, and just south of the Baja peninsula. These are water vapor holes. The satellite can see through the water vapor to the ocean surface.
Note that the water vapor holes coincide with:
1) Relatively warmer water
2) Few clouds (Baja is still dark)
Willis points out that the descending part of the Hadley circulation will have superdry air that is very warm from physical compression and that can transmit infrared radiation normally absorbed by water vapor. If there is little water vapor in the air, greenhouse effect is diminished and OLR can increase dramatically.
Under such conditions clouds merely get in the way of outbound radiation (if present they thermalize window radiation that would otherwise escape to space). By the Constructal Law (which I had previously known as the maximum entropy principle), clouds will disappear to allow increased radiation to space.
If this picture is correct than the disappearing clouds phenomena is simply part of the negative feedback mechanism that stabilizes our climate.
Richard Sharpe says: December 11, 2010 at 6:07 pm
Area of the disk that receives incoming solar radiation = pi * r^2, where r is the radius of the earth.
Total surface area of the earth = 4*pi*r^2 …
So, that averages out at 1/4 of the incoming TSI. Since the earth rotates reasonable quickly it seems like a reasonable approximation.
Thanks for that Richard, your formula goes a long way towards working out Earths total solar irradiation but that is something totally different and is not in questin nor is it mentioned anywhere. (apart from in your post.)
The Watts per square meter (W/m²) of incoming solar irradiation is a given value averaging1368W/m² pr. year. It has nothing to do with the size of the Earth because as for irradiation pr m² there can be no, or very little, difference between the Earth and its moon (because as averaged over one year, the difference in the two heavenly bodies’ distance from the Sun is close to Zero)
For questin, please read question
Great post, lots of very interesting discussion. Let me throw in a bit of real world observation from inside the thermostat.
First, to see the heat engine in action every day, go to http://www.ssd.noaa.gov/goes/east/watl/loop-avn.html
You can watch the low level clouds being sucked up into the giant thunderstorms. Especially when there is a passing hurricane to the North, you can watch the high level air being ripped off the thunderstorms and pulled to the mid-latitudes.
Second, we are living in the mountains at 4100 feet (near the town of Boquete) with a view of the Pacific, about 500 feet below the continental divide, over which we can see the Carribean. The ITCZ swings north and south over our heads. A perfect place for a climate laboratory, but that’s another story. We do have an excellent and well maintained amateur weather station with records going back about nine years.
The interesting feature of the weather here is the relationship between temperature and rainfall, which appears to be a feature of the heat engine in operation: Temperature is almost perfectly constant, while rainfall varies wildly.
On the coast, of course the temperatures are much hotter, but where we live, daily temps varies from about 60F to 80F, day and night year around. There are occasional spikes for a day at a time, but the average temperature, year around varies almost not at all. For 2009, the average monthly temps varied by less than 3.5 degrees F! http://www.boqueteweather.com/climate/data_annual.htm
Meanwhile, rainfall runs from only 0-5 inches per month in the “dry” season to more than 40 inches per month in the wet season. 2008-2010 have been exceptionally wet years, witnessed by the dramatic expansion of riverbeds that had been stable for many years before. In recent weeks the rains have tapered off, but 2010 will still clock over 210 inches for the year. It will be very interesting to see what happens as we enter the la Niña period.
The theoretical discussions are fascinating and important, but for those of us lucky enough to be living inside the thermostat of the global heat engine, it´s existence and operation are a matter of obvious reality, which we witness as some of the most spectacular and interesting weather I have seen anywhere on earth. Thanks Willis for putting it all in a formal theoretical package. I am absolutely certain, by looking out the window, that you are on the right track.
Willis asked for the matchbook version.
Basically it stems from how you dismissed the solar effect of low clouds, but there are two parts.
1. Removing low clouds means there may be 300 W/m2 of solar radiation, daily-averaged, going into the ocean instead of being reflected from the tops of these clouds, which is net warming in the earth system.
2. When there are no clouds the downwelling longwave at the surface doesn’t go to zero (from 370 W/m2 with clouds), it goes to about 250-300 W/m2 from clear sky, even if it is quite dry. The loss of 100 W/m2 is more than balanced by the 300 W/m2 gain from solar.
This has become an incredibly important thread.
OHD’s observation is shattering. It breaks every GCM into smithereens, IMO.
Willis Eschenbach says:
December 12, 2010 at 12:33 am
“There’s a very interesting journal article here that discusses the formation of stratus clouds. On p. 2153 they talk about what factors determine which kind of clouds form.
They find that if the sea is cooler than the air, the solid horizon to horizon bank of stratus forms. But if the sea is warmer than the air, individual cumulus form, with areas of clear descending air between them.”
You have to be careful which type of stratus clouds you are talking about as you have found out. Plain stratus generally forms under an inversion in a stable lapse rate in the low levels. The tops of the clouds are about the same temperature as below or even a bit warmer. These clouds are often difficult to pick out on infrared satellite photos because they are close to the temperature of the land/sea. This becomes a big problem in Canada when it is often hard to determine which areas are cloudy. When the land becomes colder is get easier because the stratus clouds tops are then actually warmer than the land. Forecasting stratus clouds is always a big headache because you are never sure how long an inversion will persist and when the low level moisture may finally get used up. It plays havoc with airlines and their landing limits.
Stratocumulus clouds form due to instability in the lower levels, as you noted happens when the water is warmer than the air. This is what produces lake effect snow squalls off the Great Lakes at this time of year, as the very cold Arctic air moves over the relatively very warm open water. This has been in great effect the past week or so as anyone living around the London Ontario region can tell you. They have been getting buried in snow squalls off the lake.
O H Dahlsveen says:
The solar constant tells you how much radiation each m^2 on an imaginary spherical surface centered around the sun and having a radius of the sun-earth distance. To get the total amount of radiation in Watts that hits the earth, you take this and multiply it by area of a disc having the radius of the earth (pi*r^2) because that is how much radiation from the sun the earth will intercept. However, to figure out how much radiation that corresponds to for each m^2 of the earth’s surface, we have to account for the fact that the earth’s surface area is 4*pi*r^2.
The end result is that there is a factor of 4 conversion between the solar constant and the average intensity of the radiation per unit area of the earth’s surface. (The reason that it is not simply a factor of 2 is because even most of the radiation that hits the half of the earth that is in daylight hits it at an oblique angle.)
Brian H:
I really hope that you are kidding and are not actually that easily led astray!
Willis – you say “I have most assuredly considered the idea that clouds drive the warming, and I find it lacking a cause. If the clouds are driving the warming, what is driving the clouds?”
Henrik Svensmark’s well-known theory, supported by actual observation and experiment, says that cosmic rays (GCRs) do in fact play a role in the formation of clouds, both over long periods and in very short periods (eg. Forbush decreases). But maybe that is not the only driver of clouds. Roy Spencer says (http://www.drroyspencer.com/research-articles/global-warming-as-a-natural-response/) “What has caused the warming seen over the last 100 years or so?
Here I present new evidence that most of the warming could be the result of a natural cycle in cloud cover forced by a well-known mode of natural climate variability: the Pacific Decadal Oscillation (PDO). […] Since this timing between the phase of the PDO and periods of warming and associated climate change seems like more than mere coincidence, I asked the rather obvious question: What if this known mode of natural climate variability (the PDO) caused a small fluctuation in global-average cloud cover?
Such a cloud change would cause the climate system to go through natural fluctuations in average temperature for extended periods of time. The IPCC simply assumes that this kind of natural cloud variability does not exist […] This is an assumption that many of us meteorologists find simplistic and dubious, at best. Spencer and Braswell (2008) showed theoretically that daily random variations in cloudiness can actually cause substantial decadal time-scale variability on ocean temperatures.” [and more…].
Unfortunately, when Roy Spencer tried to get a paper published in GRL along these lines, it was violently rejected.
I would add that the albedo measures from the Earthshine project tally very nicely with observed global temperature changes. ie, further evidence that clouds do drive temperature. Graph is here: http://members.westnet.com.au/jonas1/PalleInterAnnualAlbedo.JPG – my link to the paper is broken but I think the paper was Palle, E., P. R. Goode, and P. Montanes-Rodriguez (2009), Inter-annual trends in Earth’s reflectance 1999-2007, J. Geophys. Res., doi:10.1029/2008JD010734. [NB. albedo relates to rate of change of temperature (1st derivative)].
Coming back to your post. Your post states clearly “What would we expect to happen to this flow system if there is an increase in the temperature?“. As I read it, you are looking exclusively at the reaction of clouds to temperature – in other words you are interpreting the observed behaviour of clouds only as a reaction to temperature – the exact same mistake that is made by Lauer and the IPCC. Now there may indeed be a reaction of clouds to temperature along the lines that you suggest, but I would argue that you are putting the cart before the horse : surely by far the more important effect is the reaction of temperature to clouds.
I find it fascinating that the majority of the “heating” found by GISS and the Warmers is in the polar part of your diagram where “nothing happens” from a heat engine point of view…
I’m going to have to ponder this posting a bit more. Thanks for that!
Ok, Willis, I’ve thought about this for a while. There is only one clear response I can make. So I’ve got to set this on your table. Here’s my reply:
http://chiefio.files.wordpress.com/2010/12/dscf0540.jpg
E.M.Smith says:
December 12, 2010 at 3:11 pm
Thanks, Chiefio. My diagram is only of part of the climate system, or as I said in the caption, “Other parts of the atmospheric circulation not shown”. We can also consider the entire earth as a heat engine, in which case the main radiators are the desert belt and the poles.
Mike Jonas says:
December 12, 2010 at 2:21 pm
Mike,
My preferred mechanism for those cloudiness and albedo changes is a shift in the latitudinal position of the jetstreams as I have explained elsewhere.
The change in trend towards increases for both cloudiness and albedo as noted by the Earthshine project was in the late 90s and by 2000 I first noted that the jets were no longer so persistently poleward as they had become by the mid 90s.
That change in jetstream behaviour has greatly intensified since then and from 2007 to date has become obvious to all but some are still in denial and others lamely try to say it is down to AGW despite the correlation with the quiet sun and the failure of the present situation to have developed steadily during the entire course of the late 20th century warming spell from about 1975 onwards.
I prefer my explanation to the Svensmark hypothesis because his proposition involves cloudiness and albedo changes without any need for changed behaviour and/or positioning on the part of the jets.
Given that the jets do shift in correlation with the cloudiness and albedo changes we do not need the Svensmark idea. Unless of course Svensmark also claims that more cosmic rays can shift the jets but I don’t think he has ever suggested that.
Instead it is more likely to be a matter of a solar effect on the size and intensity of the AO and AAO operating via ozone chemistry changes within the polar vortices.
Joel Shore: December 12, 2010 at 2:00 pm
Joel Shore you tell me how to work out the total average solar irradiation the Earth receives from the Sun in much the same way as Richard Sharpe did in a post on December 11, 2010 at 6:07 pm which was in response to my original post on December 11, 2010 at 3:59 pm. A posting which you seem not to have read.
To be absolutely correct you say;
“The solar constant tells you how much radiation each m^2 on an imaginary spherical surface centered around the sun and having a radius of the sun-earth distance. To get the total amount of radiation in Watts that hits the earth, you take this and multiply it by area of a disc having the radius of the earth (pi*r^2) because that is how much radiation from the sun the earth will intercept. However, to figure out how much radiation that corresponds to for each m^2 of the earth’s surface, we have to account for the fact that the earth’s surface area is 4*pi*r^2.”
I do NOT want to know how to “work out” the total amount of radiation in Watts that hits the earth.
I know that already!
Nor do I wish to know whatever an imaginary spherical surface centered around the sun and having a radius of the sun-earth distance may be – or what it may have to do with what I wrote.
My “Thread” was briefly:
1.) According to NASA: “The solar constant is the amount of energy received at the top of the Earth’s atmosphere on a surface oriented perpendicular to the Sun’s rays (at the mean distance of the Earth from the Sun). The generally accepted solar constant of 1368 W/m2 is a satellite measured yearly average.
2.) How come the “Incoming Solar Radiation” is 341.3 W/m² as in a “Global Energy Plan W/m²” posted earlier? (By the way all other plans of that ilk that I have ever seen show very similar values.)
3.) As the incoming “solar constant” is accepted to be 1368 W/m² it should only be necessary to divide that figure by 2 (to account for day and night) and arrive at a figure of 684 W/m².
Which may only mean that all these plans can be binned.
PS
Brian H seems to have grasped the thread ok.
OHD, your factor of 0.5 does not account for the reduction in solar radiation when it hits the surface obliquely. If the sun was overhead everywhere for half the day, and nowhere the other half, 0.5 would apply. Clearly this is not a good approximation to the oblique angles over most of the earth and most of the day, and that is where the other factor of 0.5 comes from to make it 0.25.
Stephen Wilde – do you have a link where I can see more about the ‘shift in the latitudinal position of the jetstreams’?
I don’t see why all the possible influences have to be mutually exclusive. Isn’t it possible/probable that two or more of them genuinely exist and have an influence? Of course, there might also be interaction between them.
O H Daahlsveen:
Apparently not.
The quote that you give from NASA contains the answer to your query. Let me point out the important part to you that you have clearly failed to grasp the meaning of – “oriented perpendicular to the Sun’s rays”. Hint: The whole daylight side of the earth is not oriented perpendicular to the sun’s rays.
And, to quote what I told you above, which part of this do you not understand?
“Mike Jonas says:
December 12, 2010 at 5:33 pm
Stephen Wilde – do you have a link where I can see more about the ‘shift in the latitudinal position of the jetstreams’?
I don’t see why all the possible influences have to be mutually exclusive. Isn’t it possible/probable that two or more of them genuinely exist and have an influence? Of course, there might also be interaction between them.”
This is the most specific item I have found relating to the pre 2000 poleward drift:
http://www.msnbc.msn.com/id/24228037/
I have not yet found a paper that admits that the trend has now reversed but there is lots of comment on the issue and of course we can see for ourselves on a day by day basic that the jets are now looping much more equatorward than they did during the late 20th century.
As for Svensmark’s idea I don’t dismiss it completely. I just think it is more likely to be a lower order modulating efect rather than a climate driver.
Since the jets appear to shift in response to solar forcing the separate cosmic ray effect could be just a coincidental consequence of the same solar changes.
Stephen Wilde – interesting. Since they don’t know the cause, “look south of where you are and that’s probably a good guess of what your weather may be like in a few decades” should have been “look south of where you are and that’s probably a good guess of what your weather may be like if the jetstream continues to shift north“. Quite a difference.
And, as always : “proving it is a rigorous process, using complex computer models“.
I love the question “what are oak trees going to do?“. The answer is so simple (thx to Bob Carter & polar bears) : They can’t do anything, because if you look at climate history – the onset of ice ages for example – they have already gone extinct several times.
Your comment “the jets appear to shift in response to solar forcing” leaves us with not very many primary drivers of climate. It seems likely that virtually all of the climate mechanisms are non-linear / chaotic to some extent, so sorting them all out will be a challenge. Yes, computer models will be needed, but will they be the primary driver of the solutions?
Jim D and Joel Shore – I know what you are on about. However think outside “The Accepted Box” for a minute; if, in your mind, you replace the Earth with a giant ring (hula hoop) with its opening facing the Sun, then how many W/m² would pass through the opening? Would it be1368 or would it be 342 W/m²? If the answer is 342 then I give in. – However if the answer is 1368 then my original question:”—- how come the “Incoming Solar Radiation” is 341.3 W/m² as in a “Global Energy Plan W/m²” posted earlier?” is a valid one which has not yet been answered. You two have been at pains to tell me about “An accepted way” of working out the total solar irradiance of the planet. You have also told me about the approximation to the oblique angles over most of the earth and most of the day. Joel – you even say: “The reason that it is not simply a factor of 2 is because even most of the radiation that hits the half of the earth that is in daylight hits it at an oblique angle.”
It is quite correct that the oblique angle has a big influence. I will never dispute that, but it does not influence the incoming irradiation pr. m². I still believe that what I learnt in secondary (middle) school more than 55 years ago still is correct. -That went something like this: “Sunlight can be refracted away from the surface (sent back to space) by the atmosphere. It can also be reflected back to space(before it is absorbed) by the surface. The whole surface of the Earth, for ex. mountain sides, hillocks and rocks on dry land and even the crests of waves on the oceans as well as the Earth’s curvature face the incoming sunlight at an oblique angle. How oblique that angle is varies and is impossible to work out ”(The angle of the Earth’s curvature varies as well. Hence I Suppose scientists have found it acceptable to divide the incoming radiation by 4 instead of 2.
But that only proves that the figures on the various “plans global energy flows W/m² are invalid. That includes the one on feed back
O H Dahlsveen says:
That question doesn’t make sense. W/m^2 is an intensity…It is not an amount of stuff passing through. What you want to ask is how much power (in watts) passes through the ring. The answer to that question is (1368 W/m^2)*pi*r^2 where r^2 is the radius of the earth [which works out to about 1.748 *10^17 W].
Then the next question you want to ask is that if you consider that power spread out over the earth’s surface, what is the (average) intensity on that surface. Since the earth has a surface area of 4*pi*r^2, it is 1.748 *10^17 W / (4*pi*r^2), which works out to be 342 W/m^2. Of course, if you look at the calculation we have done, you can see that the pi*r^2 parts have canceled and the net effect of what you did was to divide the solar constant by 4. That 4 is simply the geometrical conversion factor between m^2 of the imaginary surface across the ring you talked about and m^2 of the earth’s surface.
This isn’t a matter of what scientists find “acceptable” to do or not. It is a matter of what is scientifically and mathematically correct.
Jim D says on December 12, 2010 at 5:17 pm
Hmmm, I don’t like your explanation very much. Since we already account for albedo separately, it should not matter whether or not the solar radiation strikes the surface obliquely or not.
What is important, as Joel Shore says, and I tried somewhat clumsily to point out above, is that the incoming radiation is averaged across the whole surface of the earth, which has an area four times that of its cross-section.
Mike Jonas said:
“Your comment “the jets appear to shift in response to solar forcing” leaves us with not very many primary drivers of climate.”
Exactly. The secret is in the word ‘primary’.
The only primary driver is the sun. The oceans are a secondary driver that modulates the effects of the primary driver over time.
There is then a plethora of lower order drivers but sun and oceans remain way out ahead of all the others combined.
As often as not the lower order drivers act against one another so that the net effect of all those drivers combined is further reduced over time.
The equilibrium that the system always seeks to retain is that between sea surface temperature and surface air temperature. The mechanism is the speed or intensity of the hydrological cycle operating via the phase changes of water. The equilibrium temperature is set by the pressure and density differentials between sea and air at the point of contact.
It is the pressure and density of the atmosphere as a whole that matters more than the composition. More GHGs other than water (unless they significantly affect total atmospheric density and pressure) will have little or no effect because the water cycle just ramps up to accommodate the extra non water GHGs and thereby maintain the sea surface / surface air temperature equilibrium. The shifting of the jets is the visible sign of that process but the shift required to deal with more CO2 would be too small to measure. The shifting that we actually do see is virtually all sun and ocean induced.
That explains the findings of Ferenc Miskolczi who appears to have ascertained that the optical depth of the atmosphere has not changed despite more CO2 content.
Richard:
The oblique angle doesn’t have anything to do with albedo. What Jim D is saying is that if the sun doesn’t hit perpendicularly to a surface, the intensity is not the 1368 W/m^2 on that surface. In particular, the intensity on a surface will go as (1368 W/m^2) * cos(theta) where theta is the angle between the sun’s rays and the normal to the surface.
Jim D’s statement and my statement are really saying the same thing in different ways: The average value of cos(theta) over a hemisphere turns out to be 1/2, which is why the factor of 1/2 that O H Dahlsveen thought should be applied to the solar constant (because half the earth is facing the sun) becomes instead a factor of 4.
The mathematics is all nice and consistent whichever way you choose to look at it.
Richard Sharpe, the first explanation given by Joel was the traditional one, the amount intercepted depends on the cross section area, but it is averaged over the surface which is four times larger. Mine was a second way, since it was clear the first one wasn’t understood. I was trying to show why it is less than 1368 W/m2 qualitatively.
Let’s try a third way. 1368 W/m2 is intercepted over pi*r^2. This is distributed over half a sphere which is 2*pi*r^2 in surface area, so a factor of 2 comes from that. The other factor of two comes from averaging over the dark side too. So 342 W/m2 is the average instantaneous flux on the earth’s surface.
Joel Shore – “The mathematics is all nice and consistent whichever way you choose to look at it.“. Well, be a little bit careful. You have looked at the Earth as a smooth sphere. But if I choose to look at it as having an undulating surface …..
Ok guys let me try once more “a fourth way” –
1) “Irradiance – The amount of electromagnetic energy incident on a surface per unit time per unit area. In the past this quantity has often been referred to as “flux”.
The Book says: “When measuring solar irradiance (via satellite), scientists are measuring the amount of electromagnetic energy incident on a surface perpendicular to the incoming radiation at the top of the Earth’s atmosphere, not the output at the solar surface.”
I say: if the intensity of the radiation that hits the top of the atmosphere above the Earth’s Equator at an angle of 90° – this spot is to be taken as a data point or “Earth’s Zenith” – is measured to be 1368 Watts per square meter (m²) then that means, as far as I understand it, that at all points in space with a clear view of the sun and at that distance from the Sun (about 149600000 km,up down or sideways) the intensity of solar radiation is 1368 W/m². It has absolutely nothing to do with the curvature of the Earth! The same intensity hits at 20 000 km further away north, south, west, or east. You may work out the surface area of a sphere in order to find out the total irradiation of that sphere (in this case the Earth.) But why do you want to do that? You just get a much larger number to work with! Why not just work with the base number of radiation intensity in Watts per square meter? That is after all what you want to end up with.
And furthermore, by accepting that the measured radiation is correct we must also accept that; all incoming solar radiation has got the potential to be equal in intensity of 1368 W/m² wherever it strikes the surface.
How much radiation (intensity) is lost because the route of radiation through the atmosphere gets longer as it flattens out, and because more and more is reflected (glanced off) from the surface as the Earth’s curvature changes is a completely different matter. But to say that the known incoming radiation must be devided by 4 because the earth is spherical does NOT COMPUTE!
Why anybody should deem it appropriate to divide incoming radiation by any factor at all because of the shape of the object it hits is a mystery to me. To divide the Earth’s annual radiation by 2 to account for 6 months of full radiation and 6 months of none however seems quite acceptable. But only for this particular kind of calculation.
Once again I have looked at your posts. And once again I must ask: How can anything that happens on earth i.e reflection –albedo – rising sea levels, finger in the dike or anything else you like to mention have any influence on the Sun?
OHD, it is geometry. 1368 W/m2 times pi*r^2 is the number of Watts intercepted, and is distributed over how many square meters of the earth’s surface, remembering the earth is rotating. This gives the average: Intercepted Watts over total surface area. How would you define an average any other way? What is the ratio of surface area to intercepting area?
OHD says:
This just means that you don’t understand it. Watts per m^2 means how many watts are incident on a square meter of surface. The orientation of that surface is surely relevant to how much radiative power is incident on it per square meter. Imagine taking a (thin) square plate 1 m by 1 m. If the normal of the plate surface directly faced the sun then you would have 1368 W hitting the plate and the intensity would be 1368 W/m^2. If you now start rotating the plate, then I think it is not hard to understand that less and less power from the sun would hit the plate because it is intercepting less and less of the sun’s energy. In fact, in the limit where you had turned the plate by 90deg, it would be intercepting almost none of the energy because it would just present toward the sun one of its thin edges, a surface that has an area of its thickness times 1 m. The only way for the number of Watts hitting that plate to decrease as you rotate it is if the intensity in W/m^2 on the 1 m^2 of surface goes down as you rotate it. In fact, the only way for it to be consistent is if you multiply the value you get when the surface is perpendicular by the factor cos(theta). If you average the value of cos(theta) over a hemispherical surface, you find the average value is 1/2. This is where the additional factor of 1/2 comes from that you are missing.
We are not taking about reflection or albedo. You are the only one who brought this up. We are talking about how much radiation from the sun the earth intercepts. And, it is you, not us, who are imagining that things on the earth influence the sun as my above example with the plate illustrates. We are the ones who have a consistent mathematical description of reality.
Joel Shore, irrespective of how much of your plate is facing the unrestricted sunlight – even if it is just 1 mm² – the intensity of the radiation would still be 1368 W m². If you do not have that figure or data (1368 W m²) you cannot work out anything that relates to it. One square millimetre (1mm²) then would intercept 1.368 W in total.
The “Global Energy Flows W m²” plan I was talking about states quite plainly “Incoming Solar Radiation 341.3 W m²” It says nothing about averages and for that reason if that plan was the only data reference available to you, then how would you work out how much solar radiation would interfere with say an Earth orbiting satellite? Or, as our moon’s distance from the Sun is very similar to that of the Earth, how would you work out its total surface irradiance?
And Jim D the figure of 342 as an average over total surface area is the same for any sphere with the same incoming solar radiation (1368 W m ²). Let us take one that is easy to work out i.e. its radius = 6 m: Πr² = 113.09734 = size of interception disc.
Ok so now we know the incoming solar radiation is 1368 W m² (not as the plan says 341.3) so, 1368×113.09734 = 154717.16 W total intercepted which is to be divided with surface area of globe i.e.
Area of global (spherical) surface: 4Πr² = 452.38934 > > 154717.16/ 452.38934 = 342 which corresponds quite well to the “341.3 W m² of Incoming Solar Radiation” described in the plan. A plan which pays no attention to the fact that only half the planet’s surface area is exposed to sunlight at any one time and the plan does not have to as it definitely says: “Incoming Solar Radiation 341.3 W m²”
People who make up these plans simply cannot keep on confusing “Total Watts received by the total surface area” with “Incoming Watts per Square meter (W m²)”
But then again, what kind of scientists made that plan up and why?
Sorry Joel, wrong calculus, – too hastily done. – One square mm would receive or intercept 0.001368 Watts total. – I was definitely wrong there.
Sorry ohd
the old books (1972) give the solar constant as 1940 cal. per minute per square cm
(100 cm= 1meter)
I am sure if you work it out correctly you must get to the 342 W/m2
OHD,
I think you agree now that 342 W/m2 is the correct number to describe an average incoming solar radiation over the surface of the earth during a day, which is the only number that matters for the long-term energy balance, and you seem to have just misinterpreted some wording in a document.
Not really the only number; the dynamics are crucial. Most of the effective incoming hits very directly in the tropics, and drives many phenomena there, ranging from the Diurnal Bulge (a huge heated swelling of the atmosphere that tracks the sun about 2 hrs lagged as the planet rotates), to violent storms, to massive evaporation, etc. OTOH, the polar circles get little incoming, and radiate the heat they receive from atmospheric and oceanic currents and circulation on a continuous basis. In the temperate zones, major swings of mostly incoming to mostly outgoing on daily and seasonal bases.
To claim that all of this is adequately covered with the 342W/m^2/annum “average” is scientific, physical, and statistical nonsense.
Yes Jim D, I spent some time yesterday and earlier today looking up some other similar plans and I came across one by Kiehl & Trenberth (1997) that states quite clearly that it is showing Global Average Energy Flows and as the different values are very similar to the ones posted here in wuwt by Willis Eschenbach under Anthony’s title “Knobs” – it must also be averages –
I shall just have to say to you and all the other guys who got involved: I am sorry if I have been coming across as an ignorant and pesky knob. I was wrong —. But, then again, on the positive side – I have learnt a lot.
OHD
Henry P
There is no longer any difficulty for me to work out the average incoming solar radiation. I have studied a lot these past few days and I have found out how these clever climate scientists do it: They take the Solar Constant (S) and divide it by 4 and there you’ve got it. In one scientific article I looked up yesterday I read:
“So to be able to compare “apples and oranges”, when climate scientists talk about energy balance and the climate system they usually convert radiation from the sun into the effective radiation averaged across the complete surface of the earth. – This is simply 1367/4 = 342.”
Note; in the quote above S = 1367 Wm²
Well I figured some time ago that seeing that a time factor is brought in, and earth only receives 12 hours daylight per day, you would have to divide by 2. The remaining amount is only true when you are exactly at the equator. Going up and down from the equator dimishes the amount of radiation because of the angle. I accepted that that there is mathematical formula for that: you just have to divide again by 2 to get to the average of 342 w/m2 of any place on earth. But it is good to remember how we got here: you can figure out easily which place on earth gets most of the sun’s heat…. More north and south gets much less energy.
Joel Shore says on December 13, 2010 at 5:44 pm
You are correct. I was confused.
However, I like to think of it this way. If the sun does not hit perpendicularly to the surface, then one square meter of the Earth’s surface intersects less than one square meter of the incoming solar radiation. The amount received by each square meter of the Earth’s surface goes as you say: TSI * cos(theta) where theta is the angle between the normal and the incoming radiation.
“The oblique angle doesn’t have anything to do with albedo.”
I can see how that must be so for the Earth as a whole all other things remaining equal.
However if one were to shift the clouds latitudinally without altering total cloud quantities (or other cloud characteristics) would those same clouds increase global albedo if placed nearer the equator and decrease global albedo if placed nearer the poles due to the changed angle of incidence onto the clouds of incoming solar energy ?
Stephen,
I didn’t mean to imply that there was no interesting interactions between obliquity and albedo. What I was saying was simply that getting the 342 W/m^2 average incoming solar radiation from the 1368 W/m^2 solar constant does not involve any consideration of albedo…It’s just geometry.
OHD, to your credit you came here to learn. Some come here just to argue, and it is hard to tell one from the other at first.
Stephen Wilde, the latitude makes a difference because 100 sq. km of clouds at the equator blocks more incoming solar radiation than at higher latitudes, just due to the subtended angle. The area that matters for albedo is that relative to the sun’s viewpoint. This is irrespective of any additional reflectance you might get from a non-normal incidence angle, which I would think is secondary to the subtended angle effect.
Jim and Joel,
Thanks for the confirmation.
I’m thinking that such latitudinal cloud shifting could well affect affect albedo more significantly than any other factor.
Such shifting seems to be intimately connected to the changes from MWP to LIA to date for example.
Much more likely to be the answer rather than the alternative cosmic ray effect from Svensmark. As the cloud bands shift equatorward the length of the interface between air masses would increase due to the greater circumference giving air mass mixing over larger areas and a significant increase in cloudiness quite apart from the increase in blocked energy so the combined effect could well be substantial.
I haven’t seen such an effect discussed or even acknowledged anywhere other than in myt own blog contributions.
Hi Stephen!
to be fair I did mention your theory also in my own blog
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
Do you have a own blog? What is your blog’s address?
What I had not realised until now (I have OHD to thank for that), even though I had known about this, (it just slipped my mind)
is that apart from the greater surface area being covered by (the same amount) clouds in the equator region, the amount of solar radiation is much bigger between the +30 and -30 latitudes then say between +30 and +90.
After I settled on that figure of 342/m2 I forgot that it is an average figure.
So, obviously, if you can prove a correlation of sun cycle activity with the movement of clouds more towards the equator versus more towards the poles, that would have a huge impact on earth’s albedo and earth’s subsequent cooling or warming.
I now have to update my own blog again……
Hi Henry, I don’t have my own blog. I just operate as a guest contributor mainly at Climaterealists.com where I have my own section and as a contributor to other blogs of my own choosing.
As regards proving a link between solar cycle activity and latitudinal jetstream variability I think one just has to watch things for a little longer.
The response of the air circulation to the recent solar quietness and in particular the development of such an extreme negative AO at around the same time should be a wake up call to everyone.
There has to be a link between solar activity and the solar vortices which then translates into a top down effect on the tropospheric air pressure distribution to affect cloud band positioning.
Some members of the climate establishment are still in denial. They say that it is just a matter of greater meridional movement rather than a change in net latitudinal position but that doesn’t make the phenomenon go away. Even if it is ‘only’ a matter of increased meridionality the result is just the same, namely longer strings of cloudiness around the planet penetrating more equatorward than was seen during the late 20th century warming period of a more active sun with a significant effect on global albedo altering energy input to the oceans and skewing the relative balance between El Nino and La Nina.
It’s obvious to me too and the idea has been developing in my mind since I first noted that the trend towards decreased meridionality started to fade away from about 2000 after having first become noticeable in the mid 70s when that warming spell began.
I don’t believe the top down solar effect is the whole story however. The solar cycles 18 and 19 were even more powerful than cycles 21, 22 and 23 but the jets were still fairly meridional then. Thus I have proposed an opposing bottom up oceanic modulating effect which is itself to some extent independently variable.
I think the logic is sound and I just have to wait for observations to prove my point. No adequate past data exists to resolve the issue because the independent variability of sun and oceans breaks the correlations frequently enough to make the effect largely disappear in the coarseness of past mulitidecadal data and the high variability of short term datsa. Nonetheless the effect remains clear on longer timescales such as from MWP to LIA to date.
The scale of the change in solar behaviour just recently has been a godsend in that it is large and dramatic enough fot its effects to become obvious over and above short term chaotic variability and the effects of other climate forcing processes.
So the simple fact is that the globe switches periodically from net warming to net cooling in response to changes in solar activity changing global albedo via cloudband redistribution. Meanwhile semi independent oceanic variability operates on the cloud bands as well for a modulating effect that obscures the solar effect except on century long timescales.
Hope you guys keep going back to this blog, as I have got more to learn about these “Global Energy Flows W/m² Plans”. By now I have concluded that all the ones I have seen that show values in W/m² are derivatives from Trenberth et al. Those that have values in percentages seem to come directly from NASA or to be copies there off. – I could, of course be wrong. But that does not really matter. They all show more or less the same things.
Of course when they say “Incoming Radiation 100%” it is even more confusing to realise that they are still talking about an average.
And furthermore it was difficult, for me to accept that the average for the Earth is the same as it would be for a ping pong ball behaving like the Earth does, in the same orbit. But having thought about it – it is all proportionate –
As I said , I do have more questions about these plans, but they re going to take some time to formulate, so I hope you do not go away while I am pondering.. Thanks.
Now back to what, at the moment is my “Hobby Horse”. I.E. “The Global Energy Flow M m²” plan, or plans. One such plan has been used by the IPCC to explain the Earth’s energy budget, so it must have been ‘peer reviewed’ and a countless number of people, among them many scientists, must have studied it.
So, after reading this post, please look at it once more and if you can, please explain to me where I go wrong.
I wish I could reproduce the “Global Energy Flow M m²” plan here but I cannot do that so I shall have to write down the various values. Hope you will all bear with me.
The values given in the particular plan that was posted here earlier by Willis Eschenbach will be used:
Incoming Solar Radiation in (all in shortwave) = 341.3 (341) W m².
Reflected by clouds, atmosphere and surface totals 101.9 (102) W m².
Absorbed by Atmosphere = 78 W m².
Absorbed by Surface = 161 W m².
That is all the incoming radiation accounted for.
Then, the rules say, to put it briefly; “what comes in must go out” and right enough 101.9 (102) W m² has already been reflected as shortwave and outgoing radiation (longwave) from all sources adds up to 238.5 W m² and if we add on the 0.9 W m² which seem to be permanently absorbed by the surface (possibly to become fossil fuels), then there it is – all a neat and tidy equilibrium.
So far I think I have understood it -but then it becomes very “Untidy” because in the Atmosphere there is written “Greenhouse Gases”.
As the total surface absorption of 161 Wm² can only be balanced by radiation from
17 Wm² thermals + 80 Wm² from evapo-transpiration + 64 Wm² from which must be surface radiation we have 161 Wm² emitted by the surface, directly and indirectly absorbed into the atmosphere + the 78 W m² from the Sun. to account for atmospheric temperatures. But as said earlier “all that is re-radiated back into space.”
Out of these untidy “Greenhouse Gases”(GHG) comes 333 W m² as “Back Radiation” and some kind of a circuit between the surface and the GHG seems to have been set up where 356 W m² (accounting for the Atmospheric Window of 40 W m²) is being re-radiated – but as 64 + 97 + 78 W m² have already been counted out/back into space in the “Tidy” bit. – I am somewhat at a loss here -. However my big question(s) is (are) not why are 333 and not 292 or even 94.5 W m² being re-radiated but how come no back radiation is ever reflected and by what ‘natural law’ do greenhouse gases operate as they seem to be able to radiate in one direction only. – Always downwards – As I see it, if they radiate 333 W m² in one direction, down to the surface, which at best can be only 50%, then they must radiate at least that amount (333 W m²) in the other direction – back into space. But they do not. So where does that energy come from? And where is it going?
Has a perpetual heat engine been set up, or does the “Greenhouse Effect” not exist at all? – Or am I missing the “blatantly obvious”.
In whatever case, one would think radiation from “Greenhouse Gases” must -just like any other travel out in all direction from the source and therefore also back to space. In which case this planet is getting rid of more energy than it receives.
OHD,
Search for Trenberth Energy Diagram using Google. That adds it all up for you. You missed that the 239 going out includes 169 from the atmosphere so, yes, the atmosphere radiates in all directions. The net radiation effect in the atmosphere is cooling, so the surface heat and evaporation provide energy to the atmosphere to balance that.
Yes Jim D, I may not have used the number 169 but I did not miss the value of 169 W m². As my posting seemed long enough as it was I did not see the need to subtract or separate out the 30W/m² from clouds + the 40 W/m² from the atmospheric Window from the 239 just to add them on again later. All the incoming shortwave radiation (except the reflected energy) went back into space via the Atmosphere as longwave radiation whether or not it came from thermals, direct absorption, latent heat (evapo-transportation) or surface radiation. It was the extra energy (shortwave radiation) created by the “GHG” I had a problem with. If I had switched it around to be an exact replica of the said energy flow plan I would still have been left over with longwave radiation or Watts per m² to spare. And still there is no answers to my questions (I shall now make the questions more specific):
1) Where do the Greenhouse gases get the energy from to radiate 333 W/m² back into space as well as towards the Earth’s surface?
2) Where on the plan does it show that an extra 333 W/m² is being radiated out to space?
3) As the answer to the above question 2) is “Nowhere” then – what qualities do the Greenhouse gases possess to enables them to send radiation in one direction (towards the surface) only?
These 3 questions I can find no answers to in any Trenberth Energy Diagram
All I can find, so far when I Search for Trenberth Energy Diagram is The Science of Doom site and all they say –so far-is: “The third important number, solar radiation absorbed into the climate system = 239 W/m2
This is simply 342 * (100% – 30%). You see slightly different numbers like 236, 240 – all related to the challenges of accurate measurement of albedo.
Some of the radiation is absorbed in the atmosphere, and the rest into the land and oceans.”
So that is easier still 341-30% = 238.7 But that does not answer my questions.
333 W/m² from back radiation must be directed one half towards the surface and the other half must be directed towards space. ( My reason for Question 2)
OHD,
Only 239 has to be radiated to space to balance the incoming total.
333 goes towards earth. The sum of these is supplied by the other arrows.
Did you look at the diagram? There is no reason the same amount has to go up as down. The top of the atmosphere is colder so it radiates less upwards than the bottom radiates downwards.
I think when considering the green house effect, what I think is often overlooked is that during the day water is evaporated. During the night or when the vapor gets colder, due to whatever reasons, most of that water vapor condenses again. When it condenses, it releases about 40 kJ per mole (=18 gr).
like I said, I am not sure, but logic would tell me that that heat is radiated in a circle around the molecules. That means 50% back to space and 50% to earth. I think it is this 50% back to earth that provides a large portion of the green house effect.
Jim D, you say: “Only 239 has to be radiated to space to balance the incoming total.”
Yes of course, that’s what I am saying too and I would even go further and say that that is all that can be radiated back to space.
You can be sure I am looking at the diagram which is right in front of me as I am writing this. The right hand arrow shows that there are an extra 333 W/m²
which have been generated somehow somewhere among the Greenhouse Gases and then are sent back to the surface as longwave Back Radiation.
I wanted an answer as to why radiation from these greenhouse gases do not radiate equally in all directions; i.e. 333 W/m² down towards the surface and therefore also 333 W/m² in all other directions, i.e. out to space?
Then the next arrow shows 396 W/m² total radiation leaving the surface. This total must, I assume, be composed from an absorbed/converted shortwave radiation of 64 W/m², which is left from absorbed shortwave after thermals and latent heat have been taken out + 333 W/m² from GHG. (We are not going to argue about 1 W/m ² as the discrepancy may be mathematical and due to “decimal exchanges”
A short way up on the right hand side of that arrow there is an Atmospheric Window where 40 W/m² bypasses the Greenhouse Gases which I can only assume is due to the length of radiation wave bands and must therefore all come from the converted shortwave radiation. But that only means that the 333 W/m² were created or generated from only 50 + 27 W/m² in the first place. How is it possible to create 333 W/m² from 77W/m²? – I have read somewhere that it is not supposed to be possible to create or to destroy energy.
Then you go on to say: “There is no reason the same amount has to go up as down.” Well, I have always been under the impression that there is a natural law about that as well which says something like this: “radiation is emitted equally in all direction from its source” Is that not a good enough reason, or am I wrong there as well?
And lastly you say: “The top of the atmosphere is colder so it radiates less upwards than the bottom radiates downwards.
That does not seem to bother the 239 W/m² part of shortwave radiation nor should it make any difference to the 333 W/m² part of radiation from an “all around back Radiation” nor to the other 356 W/m² of Surface Radiation. Yes, I know 64 W/m² out of that has already been counted into the 169 W/m² radiated back to space, but so has everything else that has been absorbed by the atmosphere. (78 +17+80+64= 239)
Henry P has a good point there which I have never thought or heard of before
OHD;
You’re charging off madly in all directions here. Settle down!
The diagram has lotsa problems, but the 333 bit is essentially saying that the “pool” of CO2 molecules above the surface is deep enough to block all escaping 14nm etc. radiation, and keeps it trapped, bouncing around, long enough to turn into heat. It happens over many many repeated emission cycles, not just one.
OHD, the budget into the atmosphere balances. 17+80+356+78=531 in, 333+169+30=532 out. So no energy needs to be created there.
As far as radiating more down than up, yes, individual layers in the atmosphere radiate equally in all directions in proportion to their temperature. Warmer air near the surface radiates more than colder air near the top. If you use an infra-red camera from space, it would show a colder temperature than one looking up from the ground. That is all these numbers are saying.
BrianH says:
“The diagram has lotsa problems, but the 333 bit is essentially saying that the “pool” of CO2 molecules above the surface is deep enough to block all escaping 14nm etc. radiation, and keeps it trapped, bouncing around, long enough to turn into heat. It happens over many many repeated emission cycles, not just one.”
I think you meant 14 um? Did you know that water vapor and oxygen also absorbs at 14-15 um? Better read my blog :
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
Jim D you say: “OHD, the budget into the atmosphere balances. 17+80+356+78=531 in, 333+169+30=532 out. So no energy needs to be created there.”
Yes, the plan, or diagram is showing that energy in and out of the atmosphere is balancing. But the numbers 356 and 333 do not make sense to me. I cannot understand where they come from, which is why I queried the correctness of the incoming solar average of 341 in the first place.
However the plan does show energy flows in and out of the whole “Earth System” which when it comes to the atmosphere seems to operate with 94 W/m² more than it can ever receive, i.e. 333W/m² instead of a number up to a maximum of 239 which is all that the atmosphere absorbs directly from the Sun and the surface (78+ 161). – Even if every little bit of longwave radiation is absorbed by greenhouse gases in the atmosphere no more than 239 W/m² can be back radiated.. – I do not dispute the existence of back radiation because as long as there is radiation from the surface there must be radiation back to the surface. It is just that the numbers do not add up. And – as it does not seem to be any escape from the “Earth System” to space for those 94 Joules (one Watt is a unit of power equal to one Joule of energy per second) then if 94 Watts or Joules per m² were to be added to every square meter of the surface every – (how often?) – Then a runaway warming would no longer be a theory. It would be a fact.
Brian H, I shall settle down but as long as the way the solar average irradiation is worked out correctly then it happens not just over many many repeated emission cycles, not just one, as you say. – It must happen continuously every second of every hour of every day 24/7
OHD, the amount of longwave radiation is more related to the temperature of the surface and atmosphere than how much it has to emit to space. Since it is warm, actually due to the greenhouse effect, there is a lot of internal radiation that stays in the atmosphere-surface system. With no greenhouse effect, it is correct that nothing can exceed 239 W/m2. These larger numbers near the ground are from the warmth due to the blanketing effect of greenhouse gases. It is heat trapping. Not sure how else to explain it.
Ok, thanks Jim D. your answer seems reasonable as if the increase is due to the greenhouse effect, and if that effect is increasing it could explain the variations in some of the numerical values in different ‘plan updates’ in addition to any small variations due to the so called “Solar Constant”.
PS. I am still, from time to time, googeling Trenberth Energy Diagrams and am finding many interesting articles and statements.
Stephen,
I have been looking at the cloud development above Africa in the past few weeks..
Remember Africa is big…
but I noted that generally speaking the clouds develop more during the day
and always above land; there are not that many clouds above the oceans here.
As to the direction of the major clouds above the continent, it seems to me definitely they are now more edging north, towards equator; definitely not towards the poles.
This coincides with what you would expect (during a quiet sun)?
Yes, Henry that is what I would expect to see.
However the main area of cloud generation is along the mid latitude jetstream air mass boundaries which create cloud over both land and ocean.
Those boundaries are greatly lengthened when the jets show more meridional movement and the degree of meridionality or zonality seems to be affected both by solar top down effects and oceanic bottom up effects.
Previously I gave greatest influence to oceanic bottom up forcings but in light of the recent huge atmospheric response to the quieter sun (which response has been developing for at least ten years now) that may have been premature.