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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Anthony wonders how this got published.
“Pollution is warming the atmosphere…”
That’s a sufficient qualification for publication in the MSM, and, sadly, some peer reviewed journals too.
This global bandwagon is destroying the planet I tell you!
In the third paragraph ITZC s/b ITCZ
“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. Heat is then transported upwards by convection, which is done by clouds (cumulus for example) and especially thunderstorms.”
It’s not conduction – it’s all convection. The non-radiative heat transfer from the surface to the atmosphere is convection. Stop the air bulk movement and this flux is practically stopped. Still air is a very fine insulator.
REPLY: There’s some conduction, a small amount, but yes, mostly convection. Updated the description – Anthony
“…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.”
Sorry, but this paragraph make *NO* sense at all! I’ll bet all that ‘previous work’ was model simulations as well. Rain, from what I understand, is caused by all those smaller droplets ‘too small to rain’ collide & make bigger drops which eventually fall as rain, depending on the speed of the updraft. However, it looks as if they are trying to make the case that the bigger the cloud, the less rain will fall from it & will just stay suspended in the anvil area. Then there is this doosie – the small droplets “…freeze and absorb more water vapor”. What in the world are they talking about?!?!?
Jeff
I’m trying to work out how people can present these papers without a deep sense of embarrassment. Perhaps they can’t. Perhaps that’s the heat increase they feel and go on about. You know – facial warming.
Don’t forget about the heat transfer associated with the phase change of water.
There is an interesting way to test this theory. I have the HRIR (High Resolution Infrared Radiometer) data from Nimbus II. Stack that up against the latest comparable data from Terra or Aqua and lets see if it holds water.
In the HRIR data the tops of the clouds in the monsoon regions went below the calibrated temperature of 210 kelvin in the data….
I have to suggest that a lot of what they said made sense. Unfortunately, they put a warmist spin onto it. In fact they said several things that are pretty reasonable:
“the larger anvils both warmed more — by trapping more heat — and cooled more — by reflecting additional sunlight back to space”>>>>>>>>>>>
If all we’re discussing is the effects of a larger anvil verus a smaller one, that statement is likely accurate.
“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.”>>>>>>>>>>>>
Again, not unexpected.
Now…. here’ the real flaw in the paper. They attribute the larger anvils to aerosols that “split up” the available water vapour, resulting in larger numbers of droplets before they get large enough to rain. I’m not sure that explanation holds water frankly, but let’s suppose for a moment that they’re right. What did they miss?
They missed the use cases where there were insufficient particles in the atmosphere to cause rain under normal circumstances, in which case the aerosols wouls promoted rain where it otherwise would not have occurred.
“…something that goes on every day in the ITZC…”
Should be ITCZ
REPLY: Fat fingered typist, fixed – Anthony
Interesting. While this suggests a source of anthropogenic warming, it wouldn’t be CO2 related. I wonder if that is problematic to the conventional wisdom (so to speak) as it would logically undercut the importance of CO2.
I would like to invite the authors to spend a few days storm chasing on the eastern plains of Colorado. Sitting in the car for hours sweltering in the afternoon heat watching the storm cells try to break through the convective cap, then after the thunderstorm finally develops, watching in awe as the cloud rockets up ward at over 200 mph. The stom building so fast you literally have to progressively tilt your head back to watch the top of the convective column rise. The after an inch or two of 40 deg F rain falls, standing beside the car at sun set, shivering in the chill of a cool 60 degree breeze and watch the ground fog drift across the soaked farm fields, and the spectacular sun sets as the thunder storm melts away and cruises off to the east to repeat that refrigeration cycle.
These storms lift cubic kilometers of hot moist air to high enough altitude for the moisture to not only condense to liquid water but to freeze out as ice crystals. Both the water droplets and ice crystals liberating huge amounts of latent heat as the phase change occurs. This air now warmed by the liberated heat rises to 60,000+ ft elevations where it can radiate enormous amounts of heat energy directly to space. Some of the up drafts are so vigorous that they form “over shooting tops” as the updraft punches up through the tropopause and pushes into the stratosphere only to sink back down below the tropopause after it radiates away its heat energy into the -30 to -50 deg F air above it.
Sometimes the cooling is so strong that the storm will lay down a layer of hail inches to feet deep that takes days to fully melt.
I bet their model completely ignores this energy transfer and loss and only considers IR radiation as if no direct cooling due to rain, or hail occurs, or direct IR radiation from the latent heat released in the cloud tops occurred, but only considers the albedo of the cloud to local sun shine..
These guys need to get out more. They probably live in a climate where the rain is warm as bath water. In strong thunderstorms the air temperature (and the rain) drops in temperature to the local dew point. In the high plains that can be a drop from the mid to high 80 deg F range into the low 60-50 deg F range in a matter of minutes. Just how much power does it take to chill a few hundred cubic kilometers of moist air by 30+ deg F in minutes?
Larry
I don’t see anything about the aerosol composition/type that will be forcing the increase in anvil size, so is there any reason to think that quantity of the aerosol will increase will correspond in any to the increase in CO2? If not, is there any reason this should be relevant to AGW?
And if the effect is as big as they imply, how about an experiment to measure it in the field?
Ally – “I’m trying to work out how people can present these papers without a deep sense of embarrassment”. The embarrassment is offset by the sure knowledge that they have funding guaranteed for the next 10 years while they sit in darkened rooms playing computer simulation games. Great job if you can get it. When will someone pull that computer plug and kick these academic masturbators out into the real world to do some real science?
Not my area of specialty but two things come immediately to mind. One, cloud and therefor storm formation is heat driven and as I recall condensation releases energy gained when water vapor is created. Two, a few degrees C change locally is not general warming or cooling. Are we counting angles again? This just sounds like a masturbation activity with the usual discredited models.
The positive aerosol radiative forcing on deep clouds could offset the negative aerosol radiative forcing on low clouds to an unknown extent.
=======
You can word that anyway you want……it’s non-sense
The negative aerosol radiative forcing on shallow clouds could offset the positive aerosol radiative forcing on deep clouds to an unknown extent….
The sex life of the bifurcated hummingbird could offset milk production in Jersey’s to an unknown extent…………..
I have to admit to not knowing all that much about science but this statement really leaves me cold:
“The positive aerosol radiative forcing on deep clouds could offset the negative aerosol radiative forcing on low clouds to an unknown extent.”
Now I have to admit to mangling the English language myself but there’s no denying that that is a poorly constructed statement. But even if it wasn’t poorly constructed it still sounds stupid. Obviously they don’t know how positive the radiative forcing is. Or maybe they do, they just don’t know how negative the radiative forcing is. Or maybe they don’t know either. Nonetheless they go ahead and say that the positive forcing ‘could’ offset the negative. But then could it not? Of course. But while these ‘educated’ people are no masters of English they were clever enough to sufficiently imply a positive feedback (as all feedbacks must be) on something they pretty much don’t have a clue. And they were clever enough to use the weak wiggly word; ‘could’.
Russ in Houston, I think that’s the greatest heat transfer mechanism of all. Water evaporates, absorbing the laten heat of evaporation; it then rises and when it get sufficiently cold at altitude, it releases it’s latent heat and falls down as water or ice, to repeat the process.
This, and 99% of other environut pronouncements, remind of the that Shyamalan ‘B’ flick; “The Happening” from 2008. Waaaaay too many people think that kind of apocalyptic nonsense is plausible and this fits in that genre. Unfortunately it is perpetuated by constant doom and gloom from nearly every media talking head and idiots with agenda’s. Many of whom ‘occupy’ influential positions in national governments and various international organizations from the UN on down.
Rational behavior in today’s world is out the window.
Of course, in (annual and global) average, the evaporative transfer (moist convection) is the predominant heat transfer mode at the surface/atmosphere interface.
I’ve been thinking along similar lines Ally.
Back when I was younger we used to believe that part of getting workers enthused was structuring the work so people felt their work was challenging and that people felt their efforts were appreciated and contributed to success.
Instead we have been observing a parade of papers that seriously challenge this enthused worker concept. One wonders just how all of these research scientists (cough cough, gag, heave, projectile expel my lunch, ow that was not a pleasant use of the words “research scientists”) manage to go home every day believing they truly earned their wages. Surely these folks are surrounded by other scientists who are not bemused or deluded and definitively know that these atmospheric perps are classic buck naked emperors.
Normally a pyramid scheme only benefits the first couple of layers of investors. With the first CAGW investors getting more strident as they struggle to continue their contributions against science; just what do new entrants into the CAGW pyramid expect? We joke about all CAGW researchers have to do is add some sentences about proving some aspect of mans contributions to CAGW disasters and the moola and honors just roll in. But surely there are limits to making this claim… Are there not?
The CAGW papers aiming for IPCC AR- climate septic repository history that we’ve had glimpses of the last few weeks causes me to think we’re past the limit. Claims have moved beyond outrageous and in some cases well into just plain absurdly synthetic. No wonder Manny boy ran away from a PBS interview given that Roger Sowell was available to provide accurate insights.
So the polluted thunder deity abstract is composed of twisted logic hidden in gerrymandered wording and comes across as some sort of perpetual motion machine. Just why would a thunderstorm ever cease existance in China? And where is all of that heat hiding? Or are these forcing factors now responsible for part of human caused climate heat disasters? Just what part of the fraction of a degree are they staking their claim on? In ten years are they going to claim they helped prevent the ice age?
“The data from China were gathered under a bilateral agreement with the China Ministry of Sciences and Technology.”
There seems to be a strong Chinese connection. I wonder if the research has some remote connection to this:
“China will begin four regional programs to artificially increase precipitation across the country before 2015, according to the newly released 12th Five-Year Plan (2011-2015) for meteorological development.
“Each year, an average of 3 trillion cubic meters of water passes over China in clouds, and only 20 percent of it falls to the ground, according to the China Meteorological Administration (CMA).
“Currently, 50 billion cubic meters of rain and snow are gained annually in artificial precipitation, but the volume could reach 280 billion cubic meters if more effective weather intervention measures are taken, according to the CMA.
“Zheng said the programs can play an important role in guaranteeing the nation’s plan to boost the annual grain yield to 550 million tons by 2020 – that target was exceeded this year with a record 571 million tons.
“A national weather intervention command center will also be established before 2015, according to the plan. ”
http://www.chinadaily.com.cn/cndy/2011-12/09/content_14236576.htm
The Beijing Weather Modification Office has already been dealing with a ten year drought in North-East China by cloud seeding using silver iodide aerosols. I wonder if they also use dry ice!
Reading the above article it looks to me as if its “models all the way down” all over again.
It is a known fact that cloudy nights are usually warmer than clear nights. Clouds are not transparent to infrared so they trap it and re-radiate back. And they also radiate their own heat.
On the other hand, during day I’d say they’d have quite strong cooling effect by reflecting visible sunlight back into space without giving it a chance to convert to infrared.
Another important (but not so well known) effect is that clouds in general warm up the atmosphere. Water vapor condensating to water droplets releases all of the heat which was stored to it during vaporisation. This generates strong convection which is keeping the cloud up in the sky, but it also heats up the air. And the more clouds, the more of such heating. But that’s not actual warming because it’s releasing heat which was trapped elsewhere (to create the vapor). So it counts as increased heat transport but not as any additional heat.
So does this mean that anthropogenic CO2 has even less effect?
Yet another “Given these conclusions what assumptions can we draw?” paper.
Or perhaps, updated to modern technology: “Given these conclusions what model can we draw?”…