From the DOE/Pacific Northwest National Laboratory, a new paper in GRL saying something that doesn’t make much sense to me. As shown in the diagram above, thunderstorms transport heat from the lower troposphere upwards. The heat source at the base of the atmosphere (at the surface) is the absorption of sunlight by the surface of the Earth. That transfers heat to the lower atmosphere by conduction (a small amount), and mostly be re-radiated Long Wave IR. Heat is then transported upwards by convection, which is done by clouds (cumulus for example) and especially thunderstorms. So, given the amount of energy transport, I’m puzzled as to how they think this new theory works as a net warming, especially when all they are doing is running a model, and providing no hard data. They say:
Pollution strengthens thunderstorm clouds, causing their anvil-shaped tops to spread out high in the atmosphere and capture heat — especially at night
Basically what they are saying is that thunderstorm anvils are enhanced by pollution, probably due to increased condensation nuclei, and those anvils act as IR reflectors at night…but…they also act as strong sunlight reflectors, something that goes on every day in the ITCZ, as Willis has pointed out with his Thermostat Hypothesis, now a peer reviewed paper. Steve McIntyre also offered a view that clouds offer a strong net negative feedback here.
But when an abstract ends with this:
The positive aerosol radiative forcing on deep clouds could offset the negative aerosol radiative forcing on low clouds to an unknown extent.
I wonder how this speculation got published in the first place.
Pollution teams with thunderclouds to warm atmosphere
New simulation study shows that atmosphere warms when pollution intensifies storms
RICHLAND, Wash. — Pollution is warming the atmosphere through summer thunderstorm clouds, according to a computational study published May 10 in Geophysical Research Letters. How much the warming effect of these clouds offsets the cooling that other clouds provide is not yet clear. To find out, researchers need to incorporate this new-found warming into global climate models.
Pollution strengthens thunderstorm clouds, causing their anvil-shaped tops to spread out high in the atmosphere and capture heat — especially at night, said lead author and climate researcher Jiwen Fan of the Department of Energy’s Pacific Northwest National Laboratory.
“Global climate models don’t see this effect because thunderstorm clouds simulated in those models do not include enough detail,” said Fan. “The large amount of heat trapped by the pollution-enhanced clouds could potentially impact regional circulation and modify weather systems.”
Clouds are one of the most poorly understood components of Earth’s climate system. Called deep convective clouds, thunderstorm clouds reflect a lot of the sun’s energy back into space, trap heat that rises from the surface, and return evaporated water back to the surface as rain, making them an important part of the climate cycle.
To more realistically model clouds on a small scale, such as in this study, researchers use the physics of temperature, water, gases and aerosols — tiny particles in the air such as pollution, salt or dust on which cloud droplets form.
In large-scale models that look at regions or the entire globe, researchers substitute a stand-in called a parameterization to account for deep convective clouds. The size of the grid in global models can be a hundred times bigger than an actual thunderhead, making a substitute necessary.
However, thunderheads are complicated, dynamic clouds. Coming up with an accurate parameterization is important but has been difficult due to their dynamic nature.
Inside a thunderstorm cloud, warm air rises in updrafts, pushing tiny aerosols from pollution or other particles upwards. Higher up, water vapor cools and condenses onto the aerosols to form droplets, building the cloud. At the same time, cold air falls, creating a convective cycle. Generally, the top of the cloud spreads out like an anvil.
Previous work showed that when it’s not too windy, pollution leads to bigger clouds . This occurs because more pollution particles divide up the available water for droplets, leading to a higher number of smaller droplets that are too small to rain. Instead of raining, the small droplets ride the updrafts higher, where they freeze and absorb more water vapor. Collectively, these events lead to bigger, more vigorous convective clouds that live longer.
Now, researchers from PNNL, Hebrew University in Jerusalem and the University of Maryland took to high-performance computing to study the invigoration effect on a regional scale.
To find out which factors contribute the most to the invigoration, Fan and colleagues set up computer simulations for two different types of storm systems: warm summer thunderstorms in southeastern China and cool, windy frontal systems on the Great Plains of Oklahoma. The data used for the study was collected by different DOE Atmospheric Radiation Measurement facilities.
The simulations had a resolution that was high enough to allow the team to see the clouds develop. The researchers then varied conditions such as wind speed and air pollution.
Fan and colleagues found that for the warm summer thunderstorms, pollution led to stronger storms with larger anvils. Compared to the cloud anvils that developed in clean air, the larger anvils both warmed more — by trapping more heat — and cooled more — by reflecting additional sunlight back to space. On average, however, the warming effect dominated.
The springtime frontal clouds did not have a similarly significant warming effect. Also, increasing the wind speed in the summer clouds dampened the invigoration by aerosols and led to less warming.
This is the first time researchers showed that pollution increased warming by enlarging thunderstorm clouds. The warming was surprisingly strong at the top of the atmosphere during the day when the storms occurred. The pollution-enhanced anvils also trapped more heat at night, leading to warmer nights.
“Those numbers for the warming are very big,” said Fan, “but they are calculated only for the exact day when the thunderstorms occur. Over a longer time-scale such as a month or a season, the average amount of warming would be less because those clouds would not appear everyday.”
Next, the researchers will look into these effects on longer time scales. They will also try to incorporate the invigoration effect in global climate models.
The research was supported by the U.S. Department of Energy Office of Science. The data from China were gathered under a bilateral agreement with the China Ministry of Sciences and Technology.
Reference: Jiwen Fan, Daniel Rosenfeld, Yanni Ding, L. Ruby Leung, and Zhanqing Li, 2012. Potential Aerosol Indirect Effects on Atmospheric Circulation and Radiative Forcing through Deep Convection, Geophys. Res. Lett. May 10, DOI 10.1029/2012GL051851 (http://www.agu.org/pubs/crossref/2012/2012GL051851.shtml)
==================================================================
Here’s the abstract:
GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L09806, 7 PP., 2012
doi:10.1029/2012GL051851
Potential aerosol indirect effects on atmospheric circulation and radiative forcing through deep convection
Key Points
- Aerosol invigoration (AIV) on deep convective clouds incurs positive radiative forcing
- AIV also leads to enhanced regional convergence, and a strong thermodynamic forcing
- Wind shear and cloud base T determine significance of aerosol invigoration effect
Jiwen Fan Pacific Northwest National Laboratory, Richland, Washington, USA
Daniel Rosenfeld Institute of Earth Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
Yanni Ding Department of Atmospheric and Oceanic Science, University of Maryland, College Park, Maryland, USA
L. Ruby Leung Pacific Northwest National Laboratory, Richland, Washington, USA
Zhanqing Li Department of Atmospheric and Oceanic Science, University of Maryland, College Park, Maryland, USA
Abstract:
Aerosol indirect effects, i.e., the interactions of aerosols with clouds by serving as cloud condensation nuclei or ice nuclei constitute the largest uncertainty in climate forcing and projection. Previous IPCC reported negative aerosol indirect forcing, which does not account for aerosol-convective cloud interactions because the complex processes involved are poorly understood and represented in climate models. Here we elucidated how aerosols change convective intensity, diabatic heating, and regional circulation under different environmental conditions. We found that aerosol indirect effect on deep convective cloud systems could lead to enhanced regional convergence and a strong top-of-atmosphere warming. Aerosol invigoration effect occurs mainly in warmed-based convection with weak shear. This could result in a strong radiative warming in the atmosphere (up to +5.6 W m−2), a lofted latent heating, and a reduced diurnal temperature difference, all of which could potentially impact regional circulation and modify weather systems. The positive aerosol radiative forcing on deep clouds could offset the negative aerosol radiative forcing on low clouds to an unknown extent.
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Gail Combs says:
May 19, 2012 at 4:02 pm
Myrrh says @ur momisugly May 19, 2012 at 2:49 am
….And others who’ve described the WATER CYCLE – this, as I’ve been trying to point out, IS MISSING from the AGWScienceFiction comic cartoon energy budget…….
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Yes Water is very much conspicuously absent. It is one of the things I first noticed.
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Myrrh says
What does it take to get reality back into these arguments?
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“Science advances one funeral at a time.” ~ Max Planck
In this case we need a whole heck of a lot of funerals. Unfortunately the young have been indoctrinated in the new religion from the day they set foot in school. This is not by accident but to make sure the next couple of generations stay brain washed so they do not mind being starved to death. Communitarianism aka sustainability, sacrifices the individual for the “common good”
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Thank you Gail – I was beginning to feel a bit lonely… 🙂
It’s been so frustrating reading arguments where they’ve been talking at cross-purposes, those with real world knowledge of water cycles and convection and so on simply assuming that the other side is using real basic physics and those without, using the fake fisics, totally unable to grasp the concepts because they don’t exist in their fiction.
I’m actually quite impressed with the attention to detail in the tweaking of real physics to create this imaginary AGW warmist world…, someone had to know the basics very well indeed to juggle the elisions, swapping of properties, taking laws out of context and so on, and, the ‘experiments’ to prove the fictional fisics incorporating these magic tricks. Even using contradictory explanations, like the scent from a bottle wafting through the classroom explained by ideal gas in empty space spontaneous diffusion, and, by Brownian motion (which presupposes volume)..
Ugh, I have to admit when I’m not trying to remain calm whenever I see the way this fictional fisics is being used to dumb down science education for the general population, it is an amusing world they’ve created through the looking glass with Al…
Mann in Disneyland preferring to speak about unicorns, rather than answer questions, and then this. What a shame Walt is not around, he could make this an adventure into phantasy land.
Regardless of their cause or intensity cummo nims suck heat off the ground and dump it at high altitude. I would be surprised actually amazed if any of the heat came back, the hottest part is that which gains the most altitude and dumps the most heat.
If pollution is making these clouds bigger it is cooling us more.
Wow. So they used real fluid dynamics coupled with real physics and real chemistry to look at the energy transfer in a cu-nim cell (or several). Ran it over 24 hours with real changes in solar irradiance. Clearly contrasted what difference anthropogenic aerosols have over biogenic aerosols? Sheesh, guess I’d better rethink my view of climate scientists, even though Cb are weather anyway and we all know weather isn’t climate.
/sarc off
Glad to hear Willis paper is published, I’ll wander off to have a read of some real science.
Donald Mitchell says: May 19, 2012 at 12:45 pm
I have a fondness for thunderstorms, and the front range and on east in Colorado have some spectacular storms. I was a storm spotter for twenty years over there, now I’m on the west of the divide, with much milder weather. I had the chance to see three storms that had tornadoes drop out of the clouds. Watching the dynamics of the turbulence is fascinating and awe inspiring.
Smokey Thanks for the link about the Marine, what a trip that must have been!
Larry Ledwick (hotrod) says: May 18, 2012 at 2:27 pm Great description Larry. I never chased storms, just spotted them for the NWS, from the foothills west of Loveland.Though having lived 11 years in Indiana, the three tornados I have seen were on Colorado’s prairies. I spent twenty years hiking around Crow Creek, north and east of Briggsdale, up toward Grover, Hereford and Keota. IIRC, the Pawnee Buttes are NE from Keota. If one hikes to the top of the elevated ground west of the Buttes, it is a fossilized sea shore, with the wave-rippled sand frozen in stone, strewn with water-rounded pebbles. It is awesome to stand on this ancient shore, several hundred feet above the nearly desert prairie.
The bigger the thunderstorm, the more energy required – where does this energy come from? The ground in the form of heat. When the heat leaves the surface, then what happens? If this created more heat, then you have a perpetual motion situation you could exploit and also a runaway thunderstorm that would give even more energy for your your PMM
“”””” Kasuha says:
May 18, 2012 at 3:50 pm
It is a known fact that cloudy nights are usually warmer than clear nights. “””””
It’s also a known fact that the days preceding warmer cloudy nights, are even warmer still than the warm cloudy nights; suggesting that it is those warmer days, that CAUSE both the warmer nights and the clouds. Clouds or no clouds, warmer or not warmer, it is still a known fact that the night just before dawn is usually colder than it was immediately after sundown, suggesting that it still COOLS at night regradless of the clouds, or irregardless of the clouds, as the case may be.
The clouds DO NOT “””””CAUSE””””” the warmer nights; the EVEN WARMER DAY before causes both the warm night, and the clouds . (by evaporating a lot of moisture during the day, which forms clouds once the temperature falls, either late in the afternoon or after sunset.) The Temperature NEVER goes up after sunset, UNLESS some external warm air mass moves into the area from some hotter place.
So these Terra-computerists know that the bigger and denser the storm cloud anvil, the more sunlight it reflects back out into space during the daylight hours. Guess whether there are more big anvil thunderstorm clouds during the day, or during the night. Guess whether these bigger anvil dirtier storm clouds ABSORB more OR less INCOMING SOLAR SPECTRUM ENERGY FROM THE SUN, than the little tichy thunderhead clean storm clouds; and guess whether more solar energy absorption in those big dirty thunderclouds, causes warming of the earth surface or cooling of the earth surface.
Do all the above simulations and calculators on a pocket abacus; or a soroban if you have one of those.
I don’t get why JKrob doesn’t get it? Most well-educated readers who stumble here do. Stop pandering to those who don’t “get it” (by that, I mean your readers).
george: about that whole daytime/nightime thing: try READING! We (scientists) understand that clouds are the single largest source of uncertainty in numerical simulations. It’s a straw man, douche bag.
Science and scientific method are in a sorry state these days. When you have a a theory that replicates observations you can and should use that theory to predict phenomena not yet observed. At that point, you need to observe these new phenomena in the real world, by way of verification of the theory.
Seems that these days, it is perfectly acceptable to publish the predictions of theory as absolute fact. Today everyone seems to forget the predictions are ( at this point ) just a tool to verify the theory.
Take for example the theory of the ether. The lack of observed changes in the speed of light when looking for the effect of the ether led to the rejection of the ether and to the maverick outsider ( Einstein ) coming up with a better theory, against the failed “consensus”.
I shudder to think of all the lost opportunities for real scientific progress caused by “scientists” not critically appraising their own models and blithely publishing their model based predictions as fact.
Recently in the press and media, I saw a report of a scientist speculating that today’s massive computing power will radically change the way science is done, as much more can be done with modeling. Science is in real trouble when people like that get to the top,and modeling is valued more than observation.