This study is being listed as proof by some of the usual alarmist types that the issue of cloud feedback is settled. Before accepting that, read this from the summary in the June 24th issue of Science by Richard A. Kerr:
The first reliable analysis of cloud behavior over past decades suggests—but falls short of proving—that clouds are strongly amplifying global warming. If that’s true, then almost all climate models have got it wrong. On page 460, climate researchers consider the two best, long-term records of cloud behavior over a rectangle of ocean that nearly spans the subtropics between Hawaii and Mexico. In a warming episode that started around 1976, ship-based data showed that cloud cover—especially low-altitude cloud layers—decreased in the study area as ocean temperatures rose and atmospheric pressure fell. One interpretation, the researchers say, is that the warming ocean was transferring heat to the overlying atmosphere, thinning out the low-lying clouds to let in more sunlight that further warmed the ocean. That’s a positive or amplifying feedback. During a cooling event in the late 1990s, both data sets recorded just the opposite changes—exactly what would happen if the same amplifying process were operating in reverse.
Here’s the press release. I’ve looked at a few news writeups on it, and the caution listed in Science about it not being proven seems to be off the reporting radar. We’ll need further studies on a global scale, and not just one patch of ocean, before the question can be fully answered. – Anthony
From Physorg.com
The role of clouds in climate change has been a major question for decades. As the earth warms under increasing greenhouse gases, it is not known whether clouds will dissipate, letting in more of the sun’s heat energy and making the earth warm even faster, or whether cloud cover will increase, blocking the Sun’s rays and actually slowing down global warming.
In a study published in the July 24 issue of Science, researchers Amy Clement and Robert Burgman from the University of Miami’s Rosenstiel School of Marine and Atmospheric Science and Joel Norris from Scripps Institution of Oceanography at UC San Diego begin to unravel this mystery. Using observational data collected over the last 50 years and complex climate models, the team has established that low-level stratiform clouds appear to dissipate as the ocean warms, indicating that changes in these clouds may enhance the warming of the planet.
Because of inconsistencies in historical observations, trends in cloudiness have been difficult to identify. The team broke through this cloud conundrum by removing errors from cloud records and using multiple data sources for the northeast Pacific Ocean, one of the most well-studied areas of low-level stratiform clouds in the world. The result of their analysis was a surprising degree of agreement between two multi-decade datasets that were not only independent of each other, but that employed fundamentally different measurement methods. One set consisted of collected visual observations from ships over the last 50 years, and the other was based on data collected from weather satellites.
“The agreement we found between the surface-based observations and the satellite data was almost shocking,” said Clement, a professor of meteorology and physical oceanography at the University of Miami, and winner of the American Geophysical Union’s 2007 Macelwane Award for her groundbreaking work on climate change. “These are subtle changes that take place over decades. It is extremely encouraging that a satellite passing miles above the earth would document the same thing as sailors looking up at a cloudy sky from the deck of a ship.”
What was not so encouraging, however, was the fact that most of the state-of-the-art climate models from modeling centers around the world do not reproduce this cloud behavior. Only one, the Hadley Centre model from the U.K. Met Office, was able to reproduce the observations. “We have a long way to go in getting the models right, but the Hadley Centre model results can help point us in the right direction,” said co-author Burgman, a research scientist at the University of Miami.
Together, the observations and the Hadley Centre model results provide evidence that low-level stratiform clouds, which currently shield the earth from the sun’s radiation, may dissipate in warming climates, allowing the oceans to further heat up, which would then cause more cloud dissipation.
“This is somewhat of a vicious cycle potentially exacerbating global warming,” said Clement. “But these findings provide a new way of looking at clouds changes. This can help to improve the simulation of clouds in climate models, which will lead to more accurate projections of future climate changes. ”
One key finding in the study is that it is not the warming of the ocean alone that reduces cloudiness — a weakening of the trade winds also appears to play a critical role. All models predict a warming ocean, but if they don’t have the correct relationship between clouds and atmospheric circulation, they won’t produce a realistic cloud response.
“I am optimistic that there will be major progress in understanding global cloud changes during the next several years,” said Norris. “The representation of clouds in models is improving, and observational records are being reprocessed to remove spurious variability associated with satellite changes and other problems.”
Source: University of Miami (news : web)
They saved the best bit ’til last:
“…observational records are being reprocessed…”
In a warming episode that started around 1976, ship-based data showed that cloud cover—especially low-altitude cloud layers—decreased in the study area as ocean temperatures rose and atmospheric pressure fell.
What satellite data from 1976 were they coordinating the ship board data to? One wonders how tightly the time constraints on the data were controlled since a small variance in lags could just as easily indicate the cloud conditions were moving the SSTs. I think I’ll save the $15 for beer and wait for someone else to do the grunt work of reading this beauty.
So we don’t understand how the clouds work and we don’t understand how the sun works, yet there’s supposed to be a scientific consensus on the long term trajectory of Earth’s temperature? It’s laughable. When we don’t understand two of the primary variables in the climate equation there is no way we can have confidence, much less consensus.
Serious question about climate models – maybe subject for a new thread ?
What does the output of a model look like ?
What level of granularity do they try to predict ? Is it just one global average temperature per year ? One per month ? One per month per continent ? One per month per 100 mile square ?
And what about rainfall ? Winds ? Frosts ? Hours of sunshine ?
It’s got to be fine-grained enough to be verifiable and useful. In fact it’s starting to look a bit like a global weather forecast.
If it’s not verifiable in a short space of time it’s worthless. 5 years maximum. All this stuff about the year 2099 is useless this year – we want to know a bit sooner if today’s model is any good.
Would be interested to hear Svensmark’s assessment of this…
Also…why is it such a big deal and out of the realm of natural variability that in warm cycles in such situations, there are less clouds?
If there is a cap of warmer dryer air aloft, then of course the positive feedback would take place.
It happens (it has happened this summer in Texas).
The quote: “Together, the observations and the Hadley Centre model results provide evidence that low-level stratiform clouds, which currently shield the earth from the sun’s radiation, may dissipate in warming climates, allowing the oceans to further heat up, which would then cause more cloud dissipation”.
Hmm…I thought higher ocean temperatures meant more volatility and heat energy for hurricanes…
We’re not talking the Persian Gulf here….
Mother Earth will always find a way to balance herself out….
CHRIS
Norfolk, VA, USA
“Using observational data collected over the last 50 years and complex climate models …”
“…by removing errors from cloud records…”
Betcha this is going to be another data-torturing exercise with no statistical significance.
Before too many people get carried away it might be wise to remember that evidence of warming is not evidence of AGW. When the models have been improved to the point that they “have the correct relationship between clouds and atmospheric circulation,” and, I’ll add, ocean circulations and solar changes, —
Wake me when that happens. —
the role of humans will likely have been relegated to insignificance.
“One key finding in the study is that it is not the warming of the ocean alone that reduces cloudiness — a weakening of the trade winds also appears to play a critical role. All models predict a warming ocean, but if they don’t have the correct relationship between clouds and atmospheric circulation, they won’t produce a realistic cloud response.”
Could the weakening of the trade winds be the cause of reduced cloudiness, and hence the warmer oceans?
Have they heard of Roy Spencer ?
I’ll just let them believe what they want. I wouldn’t want to bother them down with due diligence or anything.
I’m no scientist, but it seems the AGW activists are trying to muddy the waters in an attempt to counter Bob Carter, De freitas, McLean, and their paper showing that the extra El Nino’s are responsible for the warming of the atmosphere from 1977 till 1998….
This recent paper would seem to show the cloud behaviour that causes that warming of the ocean which 7 months later, causes warming of the atmosphere….. Which is very interesting….
However, it does cool also… So there is no “run away” effect…. So this supposed “Positive feedback” is stable…
Secondly, how does CO2 enter into the equation of clouds again?… when the process described, is evaporation by radiative processes due to albedo changes?
Slowly but surely real science is being done. The AGW mob are being dragged kicking and screaming back into the Natural variation causes Climate Change, fold.
REPLY: I think it is only coincidence that these papers were published so close to one another. I don’t see this a “counter” to Bob Carter, De freitas, and McLean. – Anthony
The first reliable analysis of cloud behavior over past decades…
Reliable according to who ?
Were I a peer who was being asked to review this study I would probably have commented something along the lines of: “It’s just an ‘awfy wee bit’ of the planet that you are looking at here so it’s probably best not to jump to any conclusions about global climate change”
And, meanwhile, back on the sun, still no sunspots…
Plus, didn’t Prof Richard Lindzen describe this with his “Iris effect”?… But show it as a Negative feedback….?
So is that the other side of the coin in this scenario?
…. just musing.
Dave Wendt…its true there were no weather satellites in 1976, but it was the year of the great PDO climate shift.
Very convenient of Clement et al to ignore three years without satellite data, so let’s hope they adjusted the model.
REPLY: There were indeed weather satellites in 1976, but they did not carry the kinds of imagers used for UAH data we know today. – Anthony
Does the paper itself give any details about the timing of the events? That is to say, does it seem more likely that the warming ocean occurred before the dissipating cloud cover, or the other way around? Fewer low-level clouds would mean more warming at the surface, so did the clouds go away for a while and let the ocean warm, or not?
“This is somewhat of a vicious cycle potentially exacerbating global warming,” said Clement. “But these findings provide a new way of looking at clouds changes. This can help to improve the simulation of clouds in climate models, which will lead to more accurate projections of future climate changes. “
So, the very clouds that water the Earth and deposit the snows are now going to parboil the Earth and destroy all life as we know it.
That’s certainly a new way of looking at things through jaded sunglasses.
What is it that they are trying to do, hypnotize the world?
Micajah (22:24:25) :
It’s circular reasoning, and nothing more than that.
Nature abhors a vacuum, and when the clouds part the sun heats the tropical water and makes more. If they didn’t move away via circulation, the Earth would be more like permanent overcast.
All I know is, when it gets cloudy here it generally gets cooler. Why just today, while sitting at the Farmers Market, I’d be baking in the sun. But as soon as some clouds blocked the sun, it was comfortably cool. So explain again how clouds exacerbate “global warming” (which isn’t global)?
“The role of clouds in climate change has been a major question for decades. As the earth warms under increasing greenhouse gases, it is not known whether clouds will dissipate, letting in more of the sun’s heat energy and making the earth warm even faster, or whether cloud cover will increase, blocking the Sun’s rays and actually slowing down global warming.”
This is still making the assumption that the factor A in AGW is near 1. Therefore the conclusion: “no matter what the clouds do in real life or in our models,
weyou are still doomed if don’t stopouryour way of life as it.”This could just be another case of which came first, the warming sea surface or the reduced amount of low level clouds. The same problem occured in the initial ice core readings where CO2 was assumed to be the cause of warming, but that was later determined wrong (by 600 to 1200 years)
So, the Svensmark hypothesis would put the chain of events as:
1. more solar activity, causing
2. less galactic cosmic particles, causing
3. less low level clouds, causing
4. more heating of the sea surface.
Meanwhile, the AGW crowd put it this way:
1. more CO2, causes
2. heating in middle troposphere (no hotspot detected), causes
3. radiative heating of sea surface, causes
4. less low level clouds.
This time, there is so little time delay that determination of which is first, less clouds or warmer sea surface, the AGW crowd may be able to get away with this.
But wait, what is the mechanism that causes warmer sea surface to result in fewer low level clouds? How can that be tested and verified using that pesky old Scientific Method?
At least the Svensmark hypothesis is being quantitatively tested. This new paper by Clement and Bergman is only documenting a coincidence. Those who poo poo the Svensmark hypothesis claim that the sunspot-climate relationship is mearly coincidence (albeit, they had to say the LIA and MWP did not exist, or were only applicable to Europe, or …..).
Looking at that unusual stratus over the ocean one can see that it is less than active. Now let’s talk about a patch of late afternoon tropical cu-nims.
It too is ‘cloud’, it too reflects heat like this stratus cloud, but..
The tropical cu-nims happen every day, they suck enormous amounts of surface heat up into Hadley cells for more efficient cooling and they continue their cooling effects into the night.
It seems obtuse of the researchers to consider a relatively rare cloud type when there is a very obvious everyday cloud type, the tropical cu-nim, that plainly does an awful lot more to our daily heat account and badly needs understanding.
Tell ’em Willis!
[snip – policy]
“Together, the observations and the Hadley Centre model results provide evidence”. I wasn’t aware that model results can provide evidence.
Phillip Bratby is correct. The output of the models is not data. Data is a measured physical phenomenon.
“The tropical cu-nims happen every day, they suck enormous amounts of surface heat up into Hadley cells for more efficient cooling and they continue their cooling effects into the night. It seems obtuse of the researchers to consider a relatively rare cloud type when there is a very obvious everyday cloud type, the tropical cu-nim, that plainly does an awful lot more to our daily heat account and badly needs understanding.”
Spot on.
Also…the stratiform clouds are partially due to the cold California Current. . Of course they tend to go away when that portion of the ocean heats up.
And when it does….the ITCZ even has a better chance of ejecting monster amounts of heat energy towards the higher latitudes via tropical cyclones….so it all balances out in the end.
CHRIS
Norfolk, VA, USA
As Gary Plyler suggests, it’s possible that the cause and effect in this study has been reversed, as mentioned in the following article by Dr. Roy Spencer:
“When researchers observe natural changes in clouds and temperature, they have traditionally assumed that the temperature change caused the clouds to change, and not the other way around. To the extent that the cloud changes actually cause temperature change, this can ultimately lead to overestimates of how sensitive Earth’s climate is to our greenhouse gas emissions.
This seemingly simple mix-up between cause and effect is the basis of a new paper that will appear in the “Journal of Climate.” The paper¹s lead author, Dr. Roy W. Spencer, a principal research scientist at The University of Alabama in Huntsville, believes the work is the first step in demonstrating why climate models produce too much global warming.”
http://www.sciencedaily.com/releases/2008/06/080611184722.htm
And then we have these findings concerning cirrus clouds, again by Dr. Spencer:
“All leading climate models forecast that as the atmosphere warms there should be an increase in high altitude cirrus clouds, which would amplify any warming caused by manmade greenhouse gases,” he said. “That amplification is a positive feedback. What we found in month-to-month fluctuations of the tropical climate system was a strongly negative feedback. As the tropical atmosphere warms, cirrus clouds decrease. That allows more infrared heat to escape from the atmosphere to outer space.”
“While low clouds have a predominantly cooling effect due to their shading of sunlight, most cirrus clouds have a net warming effect on the Earth,” Spencer said. With high altitude ice clouds their infrared heat trapping exceeds their solar shading effect.”
http://www.sciencedaily.com/releases/2007/11/071102152636.htm
So once again warmists are trying to extrapolate catastrophe from the episode of warming in the late 20th century. There is still a lot of things to be explained.
1. Was it a reduction in clouds that caused this warming, or was it the warming that caused a reduction in clouds? Chicken and egg arguement.
2. If this is an example of positive feedback, why then did it not create a tipping point for accelerated warming? Climate hystersis anyone?
3. Why is it that the oceans are currently cooling, which indicates a large natural cyclical process? Indeed why is it this entire planet cooling, all contrary to every GCM employed?
If theres no lag between reduced cloudines and heating this is will make a good proof for Svensmarks hypothesis. If heating lags reduced cloudines the fit is even better. If its the other way around Svensmark is in trouble. Is there any information on this issue in the paper?
Heat from the ocean raises the dew point of a parcel of air so it holds more moisture/ latent heat.
The atmosphere then stirs the pot to try an balance out the energy imbalances.
Eventually the parcel of air cools to below the dew point by any number of mechanisms and the moisture precipitates as cloud out which would further cool the air.
Is this not a question of weather rather than climate?
For more than 20 years, I have had a VERY SIMPLE thought related to climate variability that I just can’t let go, regardless of how models operate. So, I’m going to throw this out there…
When the world warms, due to some change in overall radiative balance (whether it be due to changes in atmospheric and oceanic circulation or whether it be due to changes in solar effects or even… hehem… greenhouse gases), there is less cloud until a new equilibrium is reached, simply because the air warms faster than the water vapour content increases and relative humidity drops (despite the very slow increase in absolute humidity). With lower RELATIVE humidity, there is less cloud until a new equilibrium is reached. I have ALWAYS thought that a warming world (not just ocean) would NOT increase cloudiness, but, rather TEMPORARILY DECREASE it. This is NOT a vicious cycle in the long term, because, eventually a new equilibrium is established with a more or less similar global cloud cover.
When the world cools, there is more cloud on a global average basis, because a slightly higher proportion of the atmosphere hits the dewpoint during the cooling and it takes time to rain/dew out the extra moisture. Again… not a vicious cycle for long, as a new equilibrium is established with similar global cloud coverage.
This would explain the observation in this paper. This would also explain the solar amplicification effect (even without cosmic radiation effects). Maybe a change from 1367 to 1361 W/m2 isn’t a big deal until the very slight cooling causes more cloud and it cools more. The reverse would be true as well.
I meant “amplification”. Can dyslexia set in during middle age?
Low altitude cloud layers—decreased in the study area as ocean temperatures rose and atmospheric pressure fell.
Less low altitude cloud = more early morning sunshine = shorter time for net radiative cooling in the early morning = higher Tmin
This is further evidence that increasing Tmin – most of the claimed global warming – is due to increased early morning sunshine, not reflected in temperatures over the rest of the day.
Ie, most of the ‘global warming’ is an artifact of how ‘global warming’ was measured. Which explains why most of it dissapeared when the satellite data became available.
OT but breaking news, NZ government has announced a target of 20% reduction of GHG by 2020. Not sure if that is from 1990 levels or from now but it probably doesn’t matter. They claim it will only add $NZ60.00 per annum to the average household. Let me be the first to call BS on this. NZ are doing the EU trick of promising to do something while doing nothing. But they are going to tax us a bit just cause they can. Greenpeace had a campaign to suggest 40% reduction by 2020. This was laughable because livestock methane emmissions account for 50% of our GHG. To achieve a 40 % reduction without killing all the sheep and cattle in nz would require an 80% reduction in CO2 emissions.
I’m not really familiar with ship board weather logs. Would it be the norm for them to include specific cloud types and altitude and coverage estimations?
The best way to test the cloud relation to warming would be to compair average cloud cover on the equator to some constant reference point away from the equator??
Being warmer at the equator, we can tell if there is more or less cloud.
One could then use that compairison to judge how a warmer planet would react. If there are less clouds at the equator, global warming will runn out of controll. If there are more clouds at the equator, one would have to assume negative feedback dominates the basic process.
My vote is for negative feedback. is this wrong?
If clouds amplify any warming, why hasn’t all the water on the planet been boiled off by now? There was about 4 billion years time to crank up the temperature through ever more clouds.
When I go to the beach I see that there’s a lot of water left.
The conclusion I draw is obvious.
There’s recent Russian study linking solar wind, cosmic rays and cloudiness in central antarctica:
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VHB-4TP49SX-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b3a10e1f8a9306ef51668bae92298f66
Ah, those vicious cycles. And to think it all starts with the bubbles in the beer. I suspected as much…
And what is the effect of clouds at night ?
“The agreement we found between the surface-based observations and the satellite data was almost shocking,”
Maybe that is the purpose they had in mind. (Think Copenhagen)
—
rbateman:
“What is it that they are trying to do, hypnotize the world?”
Exactly.
Loved these quotes:
And:
Say what?
I’ve noticed that the wind never blows unless trees are wagging about. Who knew? Trees cause wind! At sea, I’m pretty sure the wind is generated by waves, particularly the white ones.
the modern maximum of the sun has lowerd the cloud cover and warmed the oceans. Its just the other way around.
“John in NZ (01:00:51) :
OT but breaking news, NZ government has announced a target of 20% reduction of GHG by 2020. Not sure if that is from 1990 levels or from now but it probably doesn’t matter. They claim it will only add $NZ60.00 per annum to the average household. Let me be the first to call BS on this. NZ are doing the EU trick of promising to do something while doing nothing. But they are going to tax us a bit just cause they can. Greenpeace had a campaign to suggest 40% reduction by 2020. This was laughable because livestock methane emmissions account for 50% of our GHG. To achieve a 40 % reduction without killing all the sheep and cattle in nz would require an 80% reduction in CO2 emissions.”
Strewth! I thought NZ was the only shining light of sense in the pacific with regards to AGW. Well, it is clear it is seen as a revenue stream, just like GST and road user charges on petrol/diesel, and the one-off short-term 4c p/l tax on fuel for Auckland only that the whole contry had to pay for and then GST. Yes, a tax (GST) on levies, charges and taxes. I understand that a tax on a tax was illegal in NZ, like GST of the TV license, which was abolished because someone won a case in court about it.
They appear to have discovered something quite earth-shattering: that it tends to be warmer when there are less clouds!
Seriously, there is an obvious question of cause-and-effect. This study does demonstrate a strong correlation between clouds and temperatures. But you have to be very careful to establish which is the cause and which is the effect.
The ice cores appeared to prove that temperatures were driven by atmospheric carbon dioxide. But we now know it was the other way round. When Gore said “When the carbon dioxide goes up, the temperature goes up” he should have said “When the temperature goes up, the carbon dioxide goes up”.
Of course the difficulty is that often things are both a cause and an effect. In the case of the ice cores, the temperature was probably controlled by carbon dioxide to some extent (giving rise to the dreaded positive feedback). But as it can’t be seen in the record (as far as I’m aware) then the effect of CO2 on the temperature must be very small and possibly negligible. So, although the correlation between CO2 and temperature over hundreds of thousands of years is extraordinarily strong, there clearly is no significant positive feedback.
Could a similar situation apply to temperatures and clouds? The fact that I’m sitting at my desk and writing this tends to suggest that negative feedbacks are dominant. If the global climate were dominated by positive feedbacks then there would probably be no human civilisation, no climate scientists, no Al Gore….
Chris
A few thoughts about Clement et al:
The area of the North Pacific chosen for study by Clement et al is identified in their supplemental materials as 15N-25N, 145W-115W. Refer to the text for Figure S1:
http://www.sciencemag.org/cgi/data/325/5939/460/DC1/1
Though they don’t display a typical ENSO signal, the SST anomalies for that area of the Northeast Tropical Pacific are strongly influenced by ENSO, as are trade winds, cloud cover, etc. The SST Anomalies from 1950 to present clearly show the 1976 Pacific Climate Shift. And they also show a positive trend (0.068 deg C/decade), a warming, which is consistent with the tone of the study.
http://i28.tinypic.com/qqbw4j.png
However, if we shorten the period to 1975 to present, the linear trend of the SST anomalies is negative (-0.056 deg C/decade).
http://i28.tinypic.com/2uft89k.png
During El Nino events, the cloud cover and precipitation follow the warm water from the Pacific Warm Pool to the Central and Eastern Equatorial Pacific. The increase in convection over the eastern equatorial Pacific during those El Nino events should impact the trade winds and cloud amount over the area studied. Would the low cloud cover be drawn toward the equator by the convection during the El Nino events?
New Zealand is a small player in a big world. Climate Minister Nick Smith has to balance what I suspect is his personal wish (do nothing) against the need to be seen to be ‘doing something’. Because NZ is highly trade dependent, we can’t afford to outrage critical markets. Tourism is a case in point. We attract a lot of tourists through the promise of ‘100 percent pure’, ‘Clean, Green NZ’. Some of our big markets (especially the segments that visit us) are highly conservation/green values sensitive.
We are already suffering reduced arrivals because of the global recession and are struggling against the northern hemisphere perception that a trip to NZ creates ‘a huge carbon footprint’. New Zealand simply cannot afford to be seen to be doing nothing and be pilloried or ostracised for its apostasy. It is the same with agriculture; we are facing the ‘food miles’ problem as well, even though NZ lamb on the English table generates less ‘carbon’ than its Welsh equivalent, distance notwithstanding.
The previous leftist government was evangelical about ‘carbon’; we were to be the first ‘carbon neutral’ nation ever, no matter the cost. The new government (centre right) is more sanguine. We are to be ‘cautious followers’, not pioneers. This, it seems to me, is cautious following and will never eventuate. The failure of other countries to honour their various extravagant commitments will allow us to weasel out as well, as reality strikes.
As for taxes on taxes – oh, yes! GST (Goods and Services Tax) applies to everything.
Even rates (local city taxes) attract GST.
I will be very interested to see what Roy Spencer has to say about this. It’s right up his street. He may say it’s the other way round – reduced cloud cover leading to rising sea temperature. The great fault of this study is that it is a static representation of the relationship between temperature and clouds and completely ignores the dynamic behavior of cloud formation and dissipation. A clue can be found in the sentence – “One key finding in the study is that it is not the warming of the ocean alone that reduces cloudiness — a weakening of the trade winds also appears to play a critical role”. You’ll notice there is no assessment of which role is dominant.
We know two things for certain. 1. Precipitation exactly matches evaporation, and 2. The atmosphere is not saturated with water vapor. Increased trade winds would cause increased evaporation leading to surface cooling and increased cloud cover. The extra moisture would come down somewhere as precipitation so cloud cover would be greater or thicker somewhere. Interestingly, if the atmosphere was saturated with water vapor then the positive feedback (dCo2 -> dT -> dH20vapor -> dT) would be true.
I’m not convinced by this study but it’s promising that mainstream scientists are finally researching and measuring clouds. They have yet to realize that the dynamic behavior of clouds is key.
It is extremely unlikely that the earth’s climate is net positive feedback. I am an electrical engineer. When we design an amplifier with negative feedback, it is linear. This means the output responds to changes in input by moving at the designed gain. This type of amplifer is used for example as an audio amplifer. When we want to design an amplifier as a switch, we add positive feedback. This causes the amplifer to sit at one rail until the input crosses the designed threshold. Then, it slews as fast as the amplifer can move to the other rail. It is obvious to anyone living on the earth that this does not describe the earth’s climate. A system with net positive feedback cannot by definition sit in a linear range. It has to sit at one of the rails. The earth’s climate would slew from “snowball earth” to Venus and back in response to inputs. Looking out my window, this doesn’t appear to be the case!
If you look closely at the above image of the cloud coverage, you can see a few linear features of thicker cloud in the darker area. My guess is that these are ship tracks. When the atmosphere is short of condensation nuclei, cloud formation is retarded. A passing ship leaves a trail of nuclei and clouds form along the track. Just imagine for a moment the difference in the power of the sun below those thicker lines and below the blue skies in the rest of the cloud depleted region.
I cannot access the paper. However, I’d be very interested in seeing if they have any data on the CCN status of the air mass they studied, pollution of cloud droplets by oil or surfactant, cloud droplet size etc etc. If temperature fluctuations have an effect on CCN production, then I’d expect much larger temperature effects than the tiny warming CO2 contribution. For those who doubt the efficacy of CCN reduction on the formation of boundary layer cloud, there is a noticable reduction of cloud amount, and a raising of the cloud deck, downwind of a major oil-spill.*
The key to the global warming debate is the 20% of the world’s surface covered by low level stratocumulus cloud, coverage which depends on wind-speed, surface pollution, sea temperatures, atmospheric dust and biological feedbacks. Until we have new research into the influence (if any) we have on that cloud cover, I’d not spend a green cent on carbon sequestration, cap and trade or any of the rest of the proposed solutions.
Let’s see what the problem is. Then deal with it.
JF
*I’ll do a search and see if I can find an account.
So they have data for warmer oceans and less cloud. This seems a little obvious to the non-expert. Less clouds means more sun means more warming of the ocean in their study area. What am I missing?
Another bud naked emperor.
Repeat after me: clouds cool, clouds cool, clouds cool. clouds cool, clouds cool…
Do you get it now.
Here is what I don’t get.
Obviously the results presented in this report supports the Svensmark effect, assuming that this is what happening.
These scientists, the climatologists don’t they seen the close correlation with C14 proxy and the global temperature and asked themselves..hm this is strange…why is that?
Might there be some connections between solar activity and the global temperature?
Are they not exposed to this data?
Or do they don’t want to see it or know anything about it?
They do not even know exactly how clouds effect climate change, but they have got this thing modeled to perfection?
This is totally absurd.
If I were a climate scientist, I wouldn’t be bragging too much at the moment. This is seriously turning into a joke. A pathetic one at that.
And what if it is the change in clouds that is causing the warming?
This is what Roy Spencer thinks to be the case.
“Together, the observations and the Hadley Centre model results provide evidence that low-level stratiform clouds, which currently shield the earth from the sun’s radiation, may dissipate in warming climates, allowing the oceans to further heat up, which would then cause more cloud dissipation”.
What if they have it reversed?
This study seems very evasive and heavily parsed. not to mention counter factual.
My bet is it goes in the heap with MAnn and Antarctica.
This appears to be one example where a computer model can start to model the effects of clouds.
i. In one part of the worldin the subtropics.
ii. During a period of 30 years.
It’s a start.
Let’s hope that this leads to:
i. More regions being studied.
ii. Open-ness to integrate data into models, new or current, not force-fitting into dogma.
iii. Questions about why cycles of cold-dry, hot-dry, hot-wet, cold-wet occur on some spots on earth, often through decades, not months, and how these nuggets fit into that.
Science is starting to emerge in this debate.
Long may that continue.
Sounds like they are just describing cloud behavior during El Ninos and La Ninas.
Low cloud cover is known to decrease in this area of the Pacific during and leading up to El Ninos and then increase for La Ninas.
The paper certainly should have taken this into account. What exact area did they study (and is the data actually correlated to the ENSO). The abstract and the summaries do not contain any detail.
Just The Facts (21:43:57) :
So we don’t understand how the clouds work and we don’t understand how the sun works, yet there’s supposed to be a scientific consensus on the long term trajectory of Earth’s temperature?
I think what they do understand is there is a paycheck connected to global warming.
Jack Hughes (21:44:39) : What does the output of a model look like ?
Like this : $
J.Hansford (22:14:49) : Plus, didn’t Prof Richard Lindzen describe this with his “Iris effect”?… But show it as a Negative feedback….?
It seems there are many commenters who still haven’t seen Roy Spencer on negative feedback in this 2 part YouTube series :
This is nothing new. They were studying El Nino. Slow trade winds allows the Sun to heat the top layer of ocean, leading to an El Nino. No cold fronts, no storm clouds, no choppy seas. That said, the weather clouds associated with this condition did not disappear. They track rather slowly along the Jet Stream off the southern coast of California, north of the area of the Pacific studied, and bring lots of rain. And then there is the reverse. Fast trade winds clear away warm waters and allow upwelling to occur leading to La Nina. This also shifts the Jet Stream (and now fast moving weather fronts, IE clouds), to its northern track, thus drying out California. So in essence, the study centered on the equatorial belt and its signal of El Nino and La Nina. The study has the correlation of warming and clouds ass backwards (possibly in an effort to “spin it” in order to satisfy the grant?). Trade winds, SST, El Nino/La Nina, Jet Stream position, warming/cooling.
One more thing. If seas are choppy from strong trade winds, my speculation is that a bit of water is kicked up into the atmosphere along with salt spray. This would explain visible low lying clouds in the area studied during La Nina.
Freddy . . . .
“…by removing errors from cloud records…”
Betcha this is going to be another data-torturing exercise with no statistical significance.”
Data Water Boarding is not torture according to the Warmonger Guide to Climate Hysterics. They are just having a little fun with the numbers, teasing them, a tickle here, a cajole there.
Of course low level clouds dissipate when sea surfaces warm. The warmer water heats the air which can then hold more water as vapour and low level clouds dissipate.
However the warmer air with more vapour in it then accelerates the hydrological cycle and not long afterwards convection kicks in with a higher cloud base and becomes more vigorous than it would have done at a lower temperature because of the increased temperature differential betweeen the surface and space.
Envisage a summer morning near the east coast of England with low cloud coming off the North Sea making it overcast. First the increasing warmth of the day burns off the low cloud. Then if the air is unstable along come cumulus then cumulonimbus and then cirrus. The increased convection in the latter half of the process reduces insolation far more than the burning off of the low level cloud increases it.
There is so much obvious ignorance being promulgated as so called peer reviewed science that I begin to despair.
The obvious question is – “Are the clouds cause or effect?”
Clearly they are assuming they are effect (water warms, clouds thin out) , but according to Svenmark’s hypothesis, wouldn’t they be cause (clouds change due to cosmic ray effects & ocean temperature reacts, which in turn effects atmospheric temperature)
This seems pretty fundamental – anything in the article about this?
If I understand the article correctly this statement sums up their findings:
“Together, the observations and the Hadley Centre model results provide evidence that low-level stratiform clouds, which currently shield the earth from the sun’s radiation, may dissipate in warming climates, allowing the oceans to further heat up, which would then cause more cloud dissipation.”
If this is the case, why don’t the clouds alone produce a runaway effect ignoring any influence from CO2? It should work like this; warming results in fewer clouds which causes more warming which causes fewer clouds still and more warming yet. Conversely, cooling would cause more clouds which would cause more cooling. It sounds like a very unstable system unless there are negative feedbacks to counter it.
It’s a bla, bla, bla, story and when finished there is this burning question!
Where is the EVIDENCE?
Anthony, please check the spam filter. I posted a comment about 3 hours ago and it hasn’t appeared yet. It had a couple of links, including SST anomalies for the area of the study (one shows a deceasing trend in SST anomaly from 1975 to present). I’ve got a copy, just in case it disappeared.
[REPLY – Done. (Fear not. We always check the spam filter.) ~Evan]
Did the reported decrease in cloudiness, perhaps due to variations in wind, atmospheric presure, dust particles, etc., cause the ocean’s surface water to warm, or did the reported warmer ocean water, due to ocean current, tidal, wind-activated whitecaps, atmospheric pressure variations, etc., cause the clouds to dissipate? In other words, which comes first in each case, the cause or the effect? When the skewed psuedo-science promoting AGW can honestly answer these quetions, I’ll agree that the issue is settled. Meanwhile, why should we let the politicized “scientists” in Congress stick the USA with a job-killing, economy-debilitating carbon tax based on a possibly/probably fallacious unproven climate theory?
It looks like a cart and horse issue to me. The researchers note that warmer temperatures correlate well to less cloud cover and assume that it is the warmer temperatures that are causing cloud cover to decrease. It seems to me that one can argue for the opposite; that it is the change in cloud cover that drives temperatures just as Svensmark predicted in his theory.
Dave Wendt (01:08:42) :
“I’m not really familiar with ship board weather logs. Would it be the norm for them to include specific cloud types and altitude and coverage estimations?”
Yes — most ship reports are quite similar to synoptic reports.
Old time (experienced) observers can generally deliver quite reasonable estimates of cloud base heights, but coverage estimation is less accurate. Observers can’t detect even large breaks in coverage as the layer approaches the horizon.
Also humans have a hard time estimating areas. If I remember correctly (and I don’t as often these days!) some old observing manuals would note that clouds approaching from the horizon toward the observer, and ending in a straight line at an angle to the observer of 45 degrees, would cover only 1/8th of the sky.
I still don’t understand why these people don’t see the obvious. If there really was a positive feedback mechanism, then we would not be here. Temperatures would have run away millions of years ago.
The albedo data give a complicated global picture than this local announcement for the last twenty years or so, :
http://bbso.njit.edu/Research/EarthShine/literature/Palle_etal_2006_EOS.pdf
Fig 2 in: Can Earth’s Albedo and Surface
Temperatures Increase Together?
Patrick Davis (03:46:24) :
“John in NZ (01:00:51) :
“OT but breaking news, NZ government has announced a target of 20% reduction of GHG by 2020.”
But NZ is the land of the long white cloud, Ao te Aroa. It’s only right that it should pay more.
Or was that a Spoonerism for the land of the wrong white crowd in Parliament?
J.Hansford (22:05:26) :
I’m no scientist, but it seems the AGW activists are trying to muddy the waters in an attempt to counter Bob Carter, De freitas, McLean, and their paper showing that the extra El Nino’s are responsible for the warming of the atmosphere from 1977 till 1998….
===
The largest thing they are NOT addressing is WHY the El Nino/La Nina changes are occurring during this period west of this same region – greatly affecting temperatures not only right in the area around the little region they are studying so closely, but rising temp’s and then dropping average local temp’s enough to affect worldwide averages.
They cannot realistically talk about cloud changes during this time period WITHOUT explicitly relating them to the El Nino cycle!
Yet another simplistic de-meteorologized study… reality must be too painful for these people.
5th grade Science text: “Clouds form as a result of ocean breezes laden with moisture moving on shore and condensing into clouds.” You must have water vapor. Water vapor comes from bodies of water. When seas are warm and calm, water vapor sufficient to produce clouds are not present. When seas are choppy and cool, water vapor sufficient to produce clouds is present.
By the way, Red skies at morning, sailor’s warning, red skies at night, sailor’s delight is a pretty good sailing indication in the mid-latitudes (not the tropics). Just for fun, here it is:
http://www.theweatherprediction.com/habyhints/139/
3000 record lows set in continental US so far in July.
[Have a look at the neqr coastal water temps in the Atlantic, too.
I do believe our Little Minimum has his father’s eyes (Al Gore), roughly the color of your fingers just before they get frost-bitten.
http://www.accuweather.com/mt-news-blogs.asp?blog=weathermatrix&partner=&pgUrl=/mtweb/content/weathermatrix/archives/2009/07/1000_low_temp_records_set_this_july.asp
Lightning shows on radar so it should be possible to due a running index of active equatorial cu-nim?
High activity I’d expect to increase trade winds and hence equatorial heat transfer to the Hadley cells. Simply taking the heat away faster won’t necessarily lower SSTs if warmer water is surfacing.
A trade-wind/ITCZ Cu-Nim connection with some idea of the direction of causation would be useful. I’d guess and only a guess that a sharp increase in Cu-nim activity would show up 2-3 days later in trade winds.
Good thread, excellent comments. My first reaction to the study was the same as many comments… there is a HUGE assumption that less clouds are caused by more surface heat. If the study does not prove a causation effect then they can’t effectively reach their positive feedback conclusions.
This is getting ridiculous. Spencer and Braswell (2008) has been out for a year now, and people are still looking at the gross relationships between clouds and temperature as not partly, not mostly, but ENTIRELY indicative of feedback!
It’s funny though-Lindzen found the Iris in a similarly small study area (Kwajalein radar) having previous identified it in a broader region with a geostationary satellite (that is, Lindzen et al. 2001). The reaction? Crickets.
http://www.agu.org/pubs/crossref/2008/2008JD010064.shtml
This is an interesting area of the ocean. See my year-long average of satellite photos at The Thermometer Hypothesis, which shows that this particular area of the ocean is unusual in that it has a semi-permanent cloud cover. This is the only part of the Pacific in this latitude band that shows this feature.
This, of course, limits the general applicability of the finding.
The part of the study that I didn’t understand is why they looked at long-term temperature changes rather than daily temperature changes. By taking an average of morning photos and afternoon photos of the area, they would be able to get a strong temperature signal which would reveal if the correlation is real.
Next, they claim to have adjusted the data for autocorrelation … but they have not said how they did it. What they say is:
So (as is my wont, and as I advise everyone to do) I took a look for myself. I first digitized the data. Here it is:
Year, COADS low cloud, COADS Sea Surf Temp
1953, -2.592, -0.3642
1954, 0.166, -0.4877
1955, 1.5, -0.7346
1956, 0.522, -0.5617
1957, -3.036, 0.0926
1958, -6.061, 0.5741
1959, -5.171, 0.537
1960, -0.902, 0.1296
1961, 2.923, -0.3025
1962, 3.813, -0.3765
1963, 2.923, -0.2407
1964, 3.457, -0.2654
1965, 3.635, -0.2037
1966, 1.589, 0.1173
1967, -0.368, 0.3642
1968, -0.724, 0.3395
1969, 1.5, 0.0432
1970, 3.724, -0.3765
1971, 5.058, -0.5741
1972, 5.859, -0.5
1973, 6.125, -0.4259
1974, 6.837, -0.6852
1975, 6.214, -0.7963
1976, 3.368, -0.4383
1977, 1.055, -0.0185
1978, -0.457, 0.1667
1979, -1.524, 0.1296
1980, -1.791, 0.1543
1981, -1.346, 0.2778
1982, -0.724, 0.2654
1983, -0.99, 0.1667
1984, -1.257, 0.1667
1985, -1.613, 0.4259
1986, -3.125, 0.537
1987, -2.147, 0.3395
1988, -0.902, 0.1667
1989, -0.724, 0.2284
1990, 0.788, 0.3395
1991, 0.788, 0.4259
1992, -2.147, 0.6358
1993, -2.681, 0.7469
1994, -1.257, 0.5988
1995, -2.147, 0.463
Using the Nychka method, the adjusted number of degrees of freedom in the cloud dataset is 2 … and in the SST dataset it is 3. This is far, far, far from being able to establish significance. Do the math yourselves, but unless I’ve made some kind of bozo mistake, their claim of statistically significant correlation is simply not true.
However, even if we were to accept their findings as real, I have another problem with their data. This is that it claims that a half-degree change in SST drops cloud cover by 5%. But my photo average at The Temperature Hypothesis shows extensive cloud cover in the afternoon, when SST is at its highest … makes it doubtful.
Not a mystery. The earth removes excess heat by removing water from the atmosphere. The Hadley circulation intensifies, supplying more dry area to the near-tropic desert zones. This thins the clouds, but also removes water vapor which is the ultimate greenhouse gas. Radiation from the surface through the atmospheric “clear window” increases markedly. Now the earth is closer to being greenhouse gas free and cooler as a result.
The observations will stand up. The conclusions won’t.
I am struck by how much water vapor is in the air in the tropics these days.
http://weather.unisys.com/satellite/sat_wv_hem.html
The earth is trying to conserve heat.
The suggestion from some sceptics seems to be that cloud dissipates first, then extra solar shortwave warms the ocean surfaces then El Nino occurs and warms the air. In relation to the Svensmark idea it is the variation in cosmic ray intensity that causes cloudiness to increase or decrease.
The suggestion from AGW proponents is that extra downwelling IR from extra GHGs causes the sea surface temperatures to rise which inhibits the normal energy flow from ocean to air so oceans warm up which warms the air.
I disagree with both scenarios. The PDO phase shifts at approximately 30 year intervals fail to show any correlation with changes in cosmic ray intensities or CO2 emissions yet on multidecadal time scales it is clearly those phase shifts that induce changes in global air tempearture trend from warming to cooling and vice versa.
It is clear to me that what has to be happening is a regular switch by the oceans from increased rates of energy emission to the air to reduced rates and in due course back to increased rates again.
The mechanism for that remains to be ascertained but it is not driven by CO2 or any other GHG or variations in cosmic ray intensity.
Those oceanic changes in phase are not adequately described by terms such as ‘PDO’ because technically that is just a statistical artifact.
I propose that there are thus far inadequately identified changes within the oceans that generate periodical changes in the net amount of stored solar energy released to the air and that drives everything we observe within the climate system (I have previously, rather tongue in cheek, suggested the term ‘Wildean Ocean Cycles’)
Those changes profoundly affect the rate of energy flow from oceans to air to space via the size and position of all the air circulation systems combined and affect the speed of the hydrological cycle which is the primary energy transfer mechanism in the air.
The residual background trend on century timescales is adequately dealt with by slow incremental changes in solar output. Hence the progression from Roman Warm Period to Dark Ages to Mediaeval Warm Period to Little Ice Age to Modern Maximum.
We do not have any reason to attribute any of the observed changes to human activity.
Robert Wood (08:03:00) :
“I still don’t understand why these people don’t see the obvious. If there really was a positive feedback mechanism, then we would not be here. Temperatures would have run away millions of years ago.”
But THEIR feedbacks don’t feed back! LOL
Vangel (07:52:34) :
“It looks like a cart and horse issue to me.”
The whole of AGW is a cart and horse issue.
But then:
“Global warmers predict that global warming is coming, and our emissions are to blame. They do that to keep us worried about our role in the whole thing. If we aren’t worried and guilty, we might not pay their salaries. It’s that simple.”
Kary Mullis
Winner of the 1993 Nobel Prize in Chemistry.
This may have something to do with it.
“It sounds like a very unstable system unless there are negative feedbacks to counter it”
I agree. As Warren Meyer has pointed out, what’s known as “global warming” is really two distinct hypotheses:
First, that increased levels of CO2 will result in a modest increase in global surface temperatures; and
Second, that the climate system acts to greatly amplify any increase in global surface temperatures.
There’s essentially no evidence to support the second hypothesis and the natural assumption should be that any feedbacks are negative. It’s just very unlikely that the world has been walking the razor’s edge for hundreds of millions of years just waiting for some little push to push us over the edge.
Not only that, but the earth has made it through stresses much worse than doubled or tripled CO2 levels. And yet the climate has wandered back. The reasonable and natural inference is that feedbacks are negative.
Dr Roy Spencer comments on this paper on his web-site:
New Study in Science Magazine: Proof of Positive Cloud Feedback?
Basically he thinks that this study carries the same two problems as previous cloud studies, namely (1) the regional character of the study, and (2) the issue of causation when analyzing cloud and temperature changes.
This can help to improve the simulation of clouds in climate models, which will lead to more accurate projections of future climate changes. “
This should cement the divergence between models and reality.
Fascinating…
How can one have evidence that X may cause Y?
“Together, the observations and the Hadley Centre model results provide evidence that low-level stratiform clouds, which currently shield the earth from the sun’s radiation, may dissipate in warming climates, allowing the oceans to further heat up, which would then cause more cloud dissipation.”
Also – if this theory is proven wrong, then it is the end for AGW-theory – because they state clearly that clouds shield from incoming radiation.
So if warmer oceans = more clouds, then we’re home free.
This is the last stand of AGW.
brazil84 (10:56:55) :
Exactly. The assumption that positive/destabilizing feedbacks are dominating in earths climate system is very far fetched.
I would mean that the fact that life is still present on earth is a stroke of extreme luck, considering the tremendous stress that the system must have undergone during the aeons.
Ron de Haan (05:38:46) :
Another bud naked emperor.
Repeat after me: clouds cool, clouds cool, clouds cool. clouds cool, clouds cool…
Do you get it now?
Great Ron!. All these childish discussions and playstation games are but the consequence of presumptuous new age scientists denying the real causes of changing: cycles above, impossible to change by that ultramicroscopic creature called human being. So we must be humble and hear the “music of the spheres”.
All succesful forecasters do so, contrarily to those who lately have reached such degree of foolishness as to afirm that the sun has nothing to do with climate.
These are the same who, after the french (cultural) revolution, wanted to recreate the world changing and denying eternal knowledge, using such silly things as a circle of 400 degrees.
Kendrew in “Climates of the Continents” published in 1922 describes a similar climatic region off the coast of southwest Africa in the area now called Namibia and has a similar discussion of Angola.
Search Google for / benguela current clouds / Wilfrid George Kendrew is the author and the Google result is for 1927 .
The coastal areas of South America with clouds over the Ocean and none on the land can be seen here:
http://www.eosnap.com/?tag=andes-mountains
The second image caption: “Clouds hug the coast of Chile” 6-13-2009
The photo caption with this WUWT post says: “This image shows unique cloud patterns over the Pacific Ocean of (?off) the coast of Baja California, . . .”
While areas with such cloud patterns may be of “great interest” to Clement and Burgman they are neither unique nor new. That the cloud tops show as bright white their albedo is very high. The water nearby shows up nearly black, thus, having an albedo very low. Nothing new here. To document, quantify, and include such situations in scientific studies is appropriate. Cheers, I say!
See also: John F. Hultquist (21:45:16)
When effect is confused with cause, it takes positive feedback to explain behavior. The lack of positive feedback in nature should be a clue that cause has been confused with effect.
I find it easily conceivable that clouds are BOTH a positive and a negative feedback. They could, for example, have a positive feedback short term, but stronger negative feedback long term.
I also see it likely that the cause and effect relationship between sea surface temp and clouds goes BOTH ways.
For example it could be that on a short term basis, a lack of cloud cover puts more heat into the ocean. But over a longer period, the cause-effect goes the other way, with the warm water creating more cloud cover.
This leads to some very interesting possibilities when you have movement of the warm water on a large scale such as in El Nino.
Bob Tisdale has made some intriguing comments about such things (apologies to him if I’m inappropriately extending or simplifying his argument).
Examples: This thread, Bob Tisdale (04:20:02) 7/26/09; and in Niche Modeling http://landshape.org/enm/influence-of-the-southern-oscillation-on-tropospheric-temperature/?dsq=13356696#comment-13356696
John F. Hultquist (11:42:57) :
About the clouds over south america: We, in Lima city, 12 degrees south of the equator, are covered by a thick layer of clouds, which make daylight at this hour (14:45 pm) look like 6 pm. in the afternoon. In the year 1997-98 we had no winter at all, quite differently as today, so those guys looking at their computer screens instead of looking the real sky will be wrong again.
Between 1991 and 1992 there was a marked decrease in GCR and cloud cover, which, if we consider a 6 year lag while sea water saved enough energy as to provoke 1997-1998 big El Nino. So it is important to see the heat budget of the seas.
http://www.scribd.com/doc/338170/svensmark-2007cosmoclimatology
The Drudge Report has a new story on 3,000 record low temps set in July. This is one of the maps from the article: click
The more people that click on the Drudge link, the more likely that he will report similar stories.
Can’t hurt. Might help.
This stuff is getting awfully depressing. Scanning through the recent posts stack I was moved to try and come up with something from history that compares to climate science over the last quarter of a century. Where humanity has invested vast amounts of money, time, and effort, with so little tangible advancement as a result. The effort has been comparable to the Manhattan or Apollo projects, and, if worldwide expenditures are included, probably dwarfs both of them, yet the little actual advancement of the state of knowledge has mostly come from people outside the funding loop. It’s as if some guy working in his garage banged out a couple of A-bombs better than Fat Man and Little Boy or was waiting on the Moon to hang leis around the necks of Armstrong and Aldrin when they touched down.
If you google Eisenhower’s farewell address, you’ll get a boatload of hits that feature his warning about the dangers of the military-industrial complex, but what is mostly forgotten is what came immediately after that warning. He also warned about the danger inherent in government becoming the primary source of funding and control of science and research. The events of recent months have shown how fundamentally backasswards history’s reading of that speech has been. Driven by the science-government nexus, the administration and Congress are whipping us down the road to economic ruin and fundamental loss of freedom, while the military-industrial complex has labored vainly to avoid drastic procurement cuts which will lead to the destruction of more jobs than all of Waxman-Markey’s alt energy boondoggles could ever hope to replace.
Does anyone doubt that if, instead of being driven by political agendas, climate science had pursued a Feynmann like model of collecting the best available data and following it where it led, our knowledge would not have advanced well beyond its’ present sorry state. That if climate modelers had been less focused on making their models confirm the A in AGW, than with having them truly reflect the actual climate, the models would still find clouds to be such an utter mystery.
Unfortunately the politicians have now learned how useful and powerful the manipulation of science can be as tool for advancing their goals and the odds of them being convinced to abandon that power are essentially nil, which is why I find this crap so depressing.
I downloaded the COADS Ocean SST and cloud cover data for this region (monthly rather than annual) and I do not see the relationship proposed in this paper.
There is rising SSTs and rising cloud cover (about at the same rate generally with the typical variability one normally sees in ocean SST datasets).
Obviously, the data needed to be adjusted.
Bill Illis (15:39:41)
Bill, does the cloud data distinguish between clouds at different levels ?
Warmer SSTs will dissipate low cloud but provoke more evaporation and convection with the development of more, higher clouds than would otherwise have been the case.
I would expect the net effect to be negative. Higher clouds alter albedo more than do lower clouds.
Bill, where did you download the COADS SST data and the cloud cover data?
w.
RICH (14:47:46):
There are several incorrect statements or assumptions in your post:
(1) You cannot say for sure that the whole temperature drop in the day or rise at night there was due to clouds. I will agree that the significant decrease in the diurnal temperature DIFFERENCE was very likely due to clouds since they tend to cool during the day and warm at night. However, the overall temperature departures could be due to many other things such as general weather patterns. And, in general, it would be too simplistic to think of one location as providing a rigorous test anyway since there are too many other methods of heat transfer (such as advection) playing a large role in determining the local temperature.
(2) In fact, we know that in the absence of greenhouse gases, the average surface temperature of the earth would have to be close to the blackbody radiating temperature needed to have the outgoing radiation balance the incoming solar radiation. (In fact, for technical mathematical reasons, the blackbody temperature should provide an upper bound.) For the earth’s current albedo (reflectance) of ~0.3, that blackbody radiating temperature would be ~255 K, which is about 33 K below the observed average temperature of ~288 K. Admittedly, however, some of that albedo is due to clouds. However, even if we use what the earth’s albedo would be in the absence of clouds, which is apparently ~0.09, we still get a blackbody temperature of ~272 K, i.e., well below the observed surface temperature. (And, even 0 albedo gives a blackbody temperature almost 10 K below the observed average surface temperature.) What this shows us is that, in fact, the warming due to greenhouse gases (primarily from water in both its vapor and cloud forms and CO2) is larger than the cooling due to the increased albedo that the clouds provide.
From the above, I got that all climate models – bar one – are wrong. “We have a long way to go in getting the models right” and yet Gavin Schmitt can use a climate model to come to the “robust” conclusion that the sun plays only a small role???
If I am following the above paper correctly, its a chicken and egg issue. Was the warming sea clearing the sky, or was the clearer sky warming the sea?
Answer? Which ever one results in a positive feedback and media attention.
RICH (14:47:46) : Even at freezing temperatures water vapor is in the air. I wonder if all the CO2 were removed, would the Earth really freeze? Would there be enough water vapor in the air to keep atmospheric temps up? For this scenario, I am assuming the Earth isn’t covered in ice and snow.
Charlie (12:38:05) : Obviously, clouds scatter visible light, light that would not make it to the surface to become IR. Wouldn’t that be a short term negative feedback? (Or is it forcing?)
Joel Shore (16:40:56), good to hear from you. However, there is an incorrect statement or assumption on your part. You say:
Certainly, this is true at cold temperatures, because tropical clouds are a function of temperature. At cold temperatures, cumulus and cumulonimbus (thunderstorms) do not form. Thus, as you correctly state, the warming of the GHGs (primarily water vapour) is larger than the cooling effect of the clouds. This starts to warm the tropical ocean, and thus the planet. However, you are only telling half the story.
Consider what happens as temperatures increase. As the tropical ocean warms, cumulus form, reflecting heat. As the warming continues, cumulonimbus start to form.
The cumulonimbus do not simply cool by reflecting sunlight, as cumulus do. They cool by a host of very effective mechanisms, including:
1. Wind driven evaporative cooling. Once the thunderstorm starts, it creates its own wind around the base. This self-generated wind increases evaporation in several ways, particularly over the ocean.
a) Evaporation rises linearly with wind speed. At a typical squall wind speed of 10 mps (20 knots), evaporation is about ten times higher than at “calm” conditions (conventionally taken as 1 mps).
b) The wind increases evaporation by creating spray and foam, and by blowing water off of trees and leaves. These greatly increase the evaporative surface area, because the total surface area of the millions of droplets is evaporating as well as the actual surface itself.
c) To a lesser extent, surface area is also increased by wind-created waves (a wavy surface has larger evaporative area than a flat surface).
d) Wind created waves in turn greatly increase turbulence in the boundary layer. This increases evaporation by mixing dry air down to the surface and moist air upwards.
e) As spray rapidly warms to air temperature, which in the tropics is often warmer than ocean temperature, evaporation also rises above the sea surface evaporation rate.
2. Wind driven albedo increase. The white spray, foam, spindrift, changing angles of incidence, and white breaking wave tops greatly increase the albedo of the sea surface. This reduces the energy absorbed by the ocean.
3. Cold rain and cold wind. As the moist air rises inside the thunderstorm’s heat pipe, water condenses and falls. Since the water is originating from condensing or freezing temperatures aloft, it cools the lower atmosphere it falls through, and it cools the surface when it hits. In addition, the falling rain entrains a cold wind. This cold wind blows radially outwards from the center of the falling rain, cooling the surrounding area.
4. Increased reflective area. White fluffy cumulus clouds are not tall, so basically they only reflect from the tops. On the other hand, the vertical pipe of the thunderstorm reflects sunlight along its entire length. This means that thunderstorms shade an area of the ocean out of proportion to their footprint, particularly in the late afternoon.
5. Modification of upper tropospheric ice crystal cloud amounts (Linden 2001, Spencer 2007) . These clouds form from the tiny ice particles that come out of the smokestack of the thunderstorm heat engines. It appears that the regulation of these clouds has a large effect, as they are thought to warm (through IR absorption) more than they cool (through reflection).
6. Enhanced night-time radiation. Unlike long-lived stratus clouds, cumulus and cumulonimbus generally die out and vanish as the night cools, leading to the typically clear skies at dawn. This allows greatly increased nighttime surface radiative cooling to space.
7. Delivery of dry air to the surface. The air being sucked from the surface and lifted to altitude is counterbalanced by a descending flow of replacement air emitted from the top of the thunderstorm. This descending air has had the majority of the water vapor stripped out of it inside the thunderstorm, so it is relatively dry. The dryer the air, the more moisture it can pick up for the next trip to the sky. This increases the evaporative cooling of the surface.
The combination of the cumulus and cumulonimbus act together to put an effective cap on the temperature rise. If the temperature rises beyond a certain point, the rapidly increasing clouds and thunderstorms bring the temperature back down.
If the temperature falls that certain point, on the other hand, the mechanism you have correctly described in your email (GHG warming being greater than cloud cooling) takes over and raises the temperature. See, for example, Bounds on the Earth’s Surface Temperature: From the Perspective of a Conceptual Global-Mean Model for a description and a model of this process.
As a result, the global temperature stays within a narrow band. You have correctly described half of the mechanism … but you have neglected to consider the other half of the mechanism. So you are 100% right, but only half the time. As with many, many physical systems, the primary mechanisms operating above equilibrium are different from those operating below equilibrium.
My best to you,
w.
Sorry, I meant to say I downloaded the COADS data from the Climate Explorer. Someone else should replicate this in case I did something wrong.
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere
There is also low level, medium and high cloud data available from the Climate Explorer but it only covers 1983 to 2006. It is inconsistent with the COADS data.
Did I read it right that this study stopped in 1995? Right before the 1997-98 El Nino?
Bill Illis (15:39:41), I just did the exercise, and I agree with you
I downloaded the data myself and found a positive correlation between total cloud cover and SST … what’s up with that? Now, they’re looking at just low clouds … but according to their paper, both COADS total clouds and COADS low clouds are strongly positively correlated with each other, and both are strongly negatively correlated with SST. I do not find that at all.
WUWT???
I don’t get anything like what they show. I get both sea surface temperatures and clouds increasing over the period 1947-2007, quite unlike what they show. I can only get a negative correlation if I detrend both datasets … but why would you want to do that?
In short, the study looks like it might be destined for the Journal of Irreproducible Results …
w.
PS – I wrote a letter to the editor of Science Magazine, pointing out that the autocorrelation of the data means that the effective N is 2 and 3 … we’ll see if it makes it through the door.
As Dr Spencer points out the study encompasses a region that correlates with the descending portion of air (Hadley cell) that originated in the tropics as ascending air at the ITCZ. Therefore the region is associated with adiabatic heating, low relative humidity and of course deserts. Living in Denver I am well acquainted with chinooks which allow us to golf in January. Chinooks are also associated with clear skies because of the increased temperatures and low humidity. Therefore I suggest that perhaps periods of decreased cloud cover are related to periods of adiabatic heating due to unusually strong descending air.
Why don’t clouds form when sunlight warms the ocean? As water evaporates, it is carried to higher altitudes, given that heat rises, and that there is no temperature inversion. The water vapor-laden air cools as it rises and, at some point, can no longer hold the water vapor. Condensation occurs. Clouds form. Why not in this instance? Is the warm air not rising? Has some unknown mechanism caused adiabatic lapse rates to stop functioning?
Could it be that winds carried the moisure-rich air (laterally) to areas of cooler temperatures, to thereby rise and form clouds as usual? Do areas adjacent to the affected area have cloud cover more dense than might otherwise be explained?
lulo (00:48:10) :
Maybe a change from 1367 to 1361 W/m2 isn’t a big deal until the very slight cooling causes more cloud and it cools more. The reverse would be true as well.
There is no change from 1367 to 1361. Different spacecraft have different calibration. The ‘real’ changes are only of the order of 1 W/m2.
Jim (17:51:39) : It is important to remember that WV is bounded by the Clausius-Clapeyron Relation, so warmer parts of the atmosphere do tend to have higher Specific Humidity. The air would have to be very cold not to have any WV at all.
The fact that there is a temperature bound on WV does not mean that one can apply that bound to feedback analysis and assume that an atmosphere which can hold more WV automatically will (note that the atmosphere presently does not hold as much WV as it potentially could). Nevertheless I would still regard the WV and Ice-Albedo feedbacks as some of the more sensible positive feedbacks thought to exist (actually, Ice Albedo feedback is so obvious that the shock would be if it didn’t operate) and the more important question is cloud effects. I suspect that we are coming close to proving that these tend to be strongly negative.
You know, I just had an interesting thought. Even if there are no changes in clouds or WV at all, by their mere presence they act as a hemispheric scale negative feedback to the daily temperature cycle-since the albedo effects exceed the greenhouse effects during the daylight hours, clouds keep days on Earth cooler than they normally would be. During the night, only the longwave matters, so the same clouds will keep the nights warmer than they would be. Clearly simply by virtue of their existence, Clouds moderate the Earth’s temperature swings, making life on Earth much more tolerable. As occasional commenter here and at CA kim often says “I think I’ve never heard so loud, the quiet message of a cloud…”
richcar (20:20:21) : adiabatic heating
The coasts of southern California, northern Chile and adjacent Peru, and Namibia are located such that some of the following occur
a: there can be cold surface water off shore
b. or not
c: there can be winds carrying high humidity air over a warm ocean toward the coast
d. there can be high pressure zones inland and air can flow out toward the ocean from higher altitude (think S. CA’s Santa Ana wind) producing adiabatic warming
e. any of these things may not happen
Seasonally and over longer periods these patterns shift. When high pressure shifts to be over the ocean as does STHP there does not exist the mechanisms for cloud formation, rather stagnation and haze. When the air from over the ocean blows toward the land and flows over the cold water fog and low clouds form but the air also chills, and …
Remember the term troposphere means that layer of the atmosphere that turns over – because it is warmed at the surface and cooler above.
When the cold water chills the air just above it, then higher up the air is warmer – a temperature inversion – and the foggy/cloudy air won’t rise.
These things are not mysteries but they do shift and change over time and space enough to confound anyone looking for simple answers to difficult questions. Explanations for the uninitiated can be found at sources such as:
http://www.physicalgeography.net/fundamentals/7p.html
From your statement it is hard to tell what level of training you bring to these issues. I apologize if I missed on the down side, but even so, maybe someone else will find the above site just what they need. John
NOGW,
I’m confused. Chart no. 3 of the Svensmark article shows Cosmic Rays, and Clouds starting to build in 1992. They steadily build until 98′, when you end up with a Monster El Nino, and the hottest (or, at least, 2nd hottest) year in at least 800 years.
Isn’t this exactly opposite of what one would expect?
JeffM, I’m not a sailor, but my experiance is, “Air doesn’t get as hot over water.”
The sun heats rock, and sand quickly. The ocean, of course, is very deep. It heats much more slowly. You don’t have the super-heated air to “take off” and form thunderstorms.
I guess, however, the water starts of warmer in the tropics, and there is more water vapor in the atmosphere which starts the process from a higher level.
I see the AGW crowd are still whipping the dead horse, trying to get it to push the ambulance cart carrying their dying hypothesis back to the lab for a shot of ECT.
John Hultquist,
Thanks for the link to the reference on general circulation models. I was simply trying to address Dr Spencers query as to whether lack of clouds drive SST warming rather than the other way around as the study proposes. Descending warming air can dissipate clouds, feed trade winds, allowing for enhanced radiative warming of the ocean as well as enhanceed escaping long wave radiation at night.
“We have a long way to go in getting the models right, but the Hadley Centre model results can help point us in the right direction,”
But give us another 20 years and another 80 billion dollars and, we might turn up something.
Meanwhile, I have found a method to reconstruct global temperature history from two variables. The sunspot number, and length of day variation.
http://s630.photobucket.com/albums/uu21/stroller-2009/?action=view¤t=temp-hist-80.gif
As you can see, issues around the cooling water intake sensors on WWII ships have yet to be resolved.
Further, I have discovered that LOD variation relates to the motion of the sun with respect to the solar system barycentre, but talk of that is discouraged here.
So in a nutshell, its the planets and the sun that determine earths temperature.
Clouds just shift heat around inside the system, and this local study reveals naff all about the global situation.
You know, even if this cloud amplification of warming thing was true it would act on any warming that had an impact on the oceans, not just man-made warming, and certainly not just warming from CO2. So multiplying the impact of CO2 by some amplification factor but not doing the same thing for natural sources of warming is a tad hypocritical.
Clouds are a lot like CO2 and ozone. Both are NOT well mixed. They move here and there, up and down, and thin like gauze or glob together in drifts and pillows, blown by whatever wind and heat column is or is not around. The clouds in the above study may be giving the wrong impression to the investigators. They didn’t disappear, they moved outside the rectangle they studied. In my opinion, this is a very poor study and peer review is at best suspect, and at worst, absent.
Berry R says:
And, you get the idea that this is what the climate models do from where exactly?!?
Joel is right, and there’s not even any theoretical way he could be wrong. The models do not distinguish CO2 by its source. Nor do they distinguish where any given amount of warming comes from. They apply incorrect feedbacks, but they do it equitably, without discriminating by race, creed, or origin …
However … that assuredly does not mean that they model the climate with sufficient fidelity to give hundred year forecasts.
Joel: You seem to be putting words in my mouth. I was referring to the reporting of results of the models, not to the way the models themselves are constructed. In other words, if someone gives a low-ball estimate of the influence of say variation in solar input or warming from El Nino, they need to be aware that the impact of those natural variations would be amplified by this mechanism too, and they need to factor it in. Do they always or even usually? I may have missed it in the footnotes, but I don’t recall seeing this sort of thing in the articles I’ve read debunking various natural causes for temperature rises.
The clouds changes are closely associated with the familiar decadal patterns of ocean temp in the Pacific – to the extent of turning around since 1998. Cloud cover has increased again folowing the transition to cooler ocean conditions – i.e. the period in which clouds caused reinforced warming was 1976 to 1998.
The paper is interesting in reconstructing clouds over a longer period – but the only link to AGW is that 1 in umpteen models passed the cloud test.
The recent Svensmark paper seems to indicate that changes in cosmic ray flux are very important factors that regulate cloud cover. If further studies keep producing similar results changes in solar activity will be sufficient to explain all of the changes noted since the end of the LIA.
http://www.agu.org/pubs/crossref/2009/2009GL038429.shtml