Linked: aerosol pollutants and rainfall patterns

From the University of Maryland Rising air pollution worsens drought, flooding, UMD-led study shows

This graphic created by a University of Maryland-led team of researchers, illustrates their new finding that increases in air pollution and other particulate matter in the atmosphere can strongly affect cloud development in ways that reduce precipitation in dry regions or seasons, while increasing rain, snowfall and the intensity of severe storms in wet regions or seasons.

COLLEGE PARK, Md. – Increases in air pollution and other particulate matter in the atmosphere can strongly affect cloud development in ways that reduce precipitation in dry regions or seasons, while increasing rain, snowfall and the intensity of severe storms in wet regions or seasons, says a new study by a University of Maryland-led team of researchers.

The research provides the first clear evidence of how aerosols — soot, dust and other small particles in the atmosphere — can affect weather and climate; and the findings have important economic and water resource implications for regions across the United States and around the world, say the researchers and other scientists.

“Using a 10-year dataset of extensive atmosphere measurements from the U.S. Southern Great Plains research facility in Oklahoma [run by the Department of Energy’s Atmospheric Radiation Measurement program] — we have uncovered, for the first time, the long-term, net impact of aerosols on cloud height and thickness, and the resultant changes in precipitation frequency and intensity,” says Zhanqing Li, a professor of atmospheric and oceanic science at Maryland and lead author of the study.

The scientists obtained additional support for these findings with matching results obtained using a cloud-resolving computer model. The study by Li and co-authors Feng Niu and Yanni Ding, also of the University of Maryland; Jiwen Fan of Pacific Northwest National Laboratory; Yangang Liu of Brookhaven National Laboratory, Upton, NY; and Daniel Rosenfeld of The Hebrew University of Jerusalem, is published in the Nov. 13 in Nature Geoscience.

“These new findings of long-term impacts, which we made using regional ground measurements, also are consistent with different findings we obtained from an analysis of NASA’s global satellite products and have just published in a separate study. Together, they attest to the needs of tackling both climate and environmental changes that matter so much to our daily life,” says Maryland’s Li, who is also affiliated with Beijing Normal University.”

“Our findings have significant policy implications for sustainable development and water resources, especially for those developing regions susceptible to extreme events such as drought and flood. Increases in manufacturing, building of power plants and other industrial developments are often accompanied with increases in pollution whose adverse impacts on weather and climate, as revealed in this study, can undercut economic gains,” he stresses.

Tony Busalacchi, chair of the Joint Scientific Committee, World Climate Research Program notes the significance of the new findings. “Understanding interactions across clouds, aerosols, and precipitation is one of the grand challenges for climate research in the decade ahead, as identified in a recent major world climate conference. Findings of this study represent a significant advance in our understanding of such processes with significant implications for both climate science and sustainable development,” says Busalacchi, who also is professor and director of the University of Maryland Earth System Science Interdisciplinary Center.

“We have known for a long time that aerosols impact both the heating and phase changes [condensing, freezing] of clouds and can either inhibit or intensify clouds and precipitation,” says Russell Dickerson, a professor of atmospheric and oceanic science at Maryland. “What we have not been able to determine, until now, is the net effect. This study by Li and his colleagues shows that fine particulate matter, mostly from air pollution, impedes gentle rains while exacerbating severe storms. It adds urgency to the need to control sulfur, nitrogen, and hydrocarbon emissions.”

According to climate scientist Steve Ghan of the Pacific Northwest National Laboratory, “This work confirms what previous cloud modeling studies had suggested, that although clouds are influenced by many factors, increasing aerosols enhance the variability of precipitation, suppressing it when precipitation is light and intensifying it when it is strong. This complex influence is completely missing from climate models, casting doubt on their ability to simulate the response of precipitation to changes in aerosol pollution.”

Aerosol Science

Aerosols are tiny solid particles or liquid particles suspended in air. They include soot, dust and sulfate particles, and are what we commonly think of when we talk about air pollution. Aerosols come, for example, from the combustion of fossil fuels, industrial and agricultural processes, and the accidental or deliberate burning of fields and forests. They can be hazardous to both human health and the environment.

Aerosol particles also affect the Earth’s surface temperature by either reflecting light back into space, thus reducing solar radiation at Earth’s surface, or absorbing solar radiation, thus heating the atmosphere. This variable cooling and heating is, in part, how aerosols modify atmospheric stability that dictates atmospheric vertical motion and cloud formation. Aerosols also affect cloud microphysics because the serve as nuclei around which water droplets or ice particles form. Both processes can affect cloud properties and rainfall. Different processes may work in harmony or offset each other, leading to a complex yet inconclusive interpretation of their long-term net effect.

Greenhouse gases and aerosol particles are two major agents dictating climate change. The mechanisms of climate warming impacts of increased greenhouse gases are clear (they prevent solar energy that has been absorbed by the earth’s surface from being radiated as heat back into space), but the climate effects of increased aerosols are much less certain. Until now, studies of the long-term effects of aerosols on climate change have been largely lacking and inconclusive because their mechanisms are much more sophisticated, variable, and tangled with meteorology.

“This study demonstrates the importance and value of keeping a long record of continuous and comprehensive measurements such as the highly instrumented (ARM) sites run by the Department of Energy’s Office of Science, including the Southern Great Plains site, to identify and quantify important roles of aerosols in climate processes,” says Stephen E. Schwartz, a scientist at Brookhaven National Laboratory. “While the mechanisms for some of these effects remain uncertain, the well-defined relationships discovered here clearly demonstrate the significance of the effects. Developing this understanding to represent the controlling processes in models remains a future challenge, but this study clearly points in important directions.”

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Support for this research was provided by the Department of Energy, NASA, the National Science Foundation and the Chinese Ministry of Science and Technology.

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November 14, 2011 12:33 am

Why is it that any study that shows warming or alarmism only needs 10 years of data, but if it shows cooling or non alarmism 10 years isn’t good enough and 17 years is required.
At least this study says biofuels aren’t going to make a bit of difference (same pollution as any other carbon based fuel).

Legatus
November 14, 2011 12:34 am

Two things:
Well, could I see some data, you know, to back it up? Maybe something showing how much and under what conditions with what kind of aerosols.
And, if this is true, we should see a lot of this going on in China right now, do we?

November 14, 2011 12:41 am

“We have known for a long time that aerosols impact both the heating and phase changes [condensing, freezing] of clouds and can either inhibit or intensify clouds and precipitation,”
Ah, the sulfurous smell of Chinese communist propaganda in the morning! So just like CO2 can cause both hot and cold, aerosols can cause more rain and less rain. I smell a model-based study into which some token data have been stuffed, inverted, adjusted, homogenized, tortured, then vomited out as a political paper, not science.

November 14, 2011 1:10 am

One interesting thing about aerosols is they give the same mid-troposphere warming signature as GHGs, but while GHGs warm the troposphere by impeding heat loss upward thus warming the climate, aerosols imped heat gain downward by blocking solar irradiance, thus cooling the climate.
The models attribute pretty much all the tropospheric warming to GHGs. I’m reasonably sure aerosols cause a large portion of it. And tropospheric warming is as much a signature of climate cooling as it is of climate warming.

handjive
November 14, 2011 1:26 am

The Botswana Gazette, 09 November 2011:
[ http://www.gazettebw.com/index.php?option=com_content&view=article&id=11848:botswana-talks-global-warming&catid=18:headlines&Itemid=2 ]
Ordinary folks puzzled
“Don’t you know that scientists lie a lot to make money?
I don’t believe them when they tell us that there is global warming because of emissions from fire or burning coal.
What I know is that when smoke goes up the sky it triggers rainfall and that is what we need in this country.”
These were the words of the unemployed Mothusi Songa as he sat alone in front of his shack in Old Naledi when The Gazette visited the area.
Songa does not believe that the recent heat waves were due to global warming because Botswana has always been a hot country thus to him an extra hot day is not a surprise.”
(via Luboš Motl)
[ http://motls.blogspot.com/2011/11/science-climate-sensitivity-is-17-26-c.html ]

November 14, 2011 1:30 am

Not mentioned is the major source of aerosols- the oceans surface. But that would be omitted because fossil fuel burning is their target.

Gator
November 14, 2011 1:33 am

But, but, but the models…
If I see one more paper based upon models I am going to puke. Somebody get me a bucket!

nc
November 14, 2011 1:54 am

I was looking for the money maker and was not disappointed, “Greenhouse gases and aerosol particles are two major agents dictating climate change. “

Ask why is it so?
November 14, 2011 2:01 am

So if we reduce pollution this will solve the droughts and flooding rains. If they succeed here in Australia then we will definitely have climate change.
I don’t know whether to take this post seriously or not.

petermue
November 14, 2011 2:04 am

Does that mean that all began in the 70s/80s with the common introduction of catalytic converters and (soot, but not only) filters of any kind, powered by the Green & Clean act?
Lesser aerosols and particles mean lesser precip and therefore lesser cooling?
That would also correlate with the starting point of the temperature incline since that date.

Alvin
November 14, 2011 2:53 am

Did this come from their marketing department?

Claude Harvey
November 14, 2011 3:14 am

How did Daniel Rosenfeld got into the Asian Cloud Gang?

November 14, 2011 3:35 am

Lower level pollutants, who woulda thunk it? Has anyone checked to see if anyone involved with the IPCC stayed awake in thermo 101? Oh, that’s not required in liberal arts.

November 14, 2011 3:46 am

Lesser aerosols and particles mean lesser precip and therefore lesser cooling?
I doubt there is much of a precipitation effect. All water vapour in the atmosphere eventually ends up as precipitation somewhere.
It’s how long water vapour hangs around in the atmosphere that matters, when it forms clouds, and what kind of clouds.
The key effect IMO is that aerosol induced clouds have smaller droplet size and more reflective of solar radiation, Thus cooling the climate.
Otherwise your are correct, less aerosols,means fewer clouds and more solar insolation, warming the climate.

Editor
November 14, 2011 4:11 am

They don’t know where the aerosols come from. They assume from industrial activity. In green-speak, that’s bad.
They don’t know what effect aerosols have on climate. They could do just about anything. Whatever they do (less rain in dry areas, severe rain in wet areas, etc) appears to be bad.
They didn’t study greenhouse gases at all, yet state that increasing them will warm the planet, and in spite of the obvious benefits of a warmer planet they make it sound bad.
They state that increased industrialisation causes side effects which undercut economic gains, ie. bad effects. I don’t suppose for a moment that they actually quantified those side effects or even made the slightest attempt to.
Why do all these papers try to make out that everything isbad?
NB. Rhetorical question, don’t bother to reply, I know the answer perfectly well. It is “If we want a good environmental policy in the future, we’ll have to have a disaster.” – Sir John Houghton.
Please note that I have not quoted the better-known “unless we announce disasters, no-one will listen” because Sir John has stated categorically “I have never said that. … [they] say it comes from the first edition of my global warming book … It does not appear in that book in any shape or form.“. http://news.bbc.co.uk/2/hi/uk_news/wales/8511780.stm
However, before you start thinking that Sir John has been badly misrepresented, note the qualifier “in that book“. The better-known misquote has, it seems, morphed from the quote that I did use, which was indeed said by Sir John according to http://rabett.blogspot.com/2010/02/defining-denial-down_17.html
So it seems that Sir John has in fact said it in some shape or form, it’s just that he didn’t say it “in that book“. So why does he protest so vehemently? (Rhetorical again).
Maybe I should have used “The threat of environmental crisis will be the ‘international disaster key’ that will unlock the New World Order.” Mikhail Gorbachev. Nah, I’ll stick with Sir John’s rare moment of honesty, it has more ‘punch’.

wayne
November 14, 2011 4:16 am

“All water vapour in the atmosphere eventually ends up as precipitation somewhere.”
Well….but wait, not locally, way too many aerosols and particles create things like the self-feeding Dust Bowl of the ’30’s. With that many particles you would think it would be flooding but instead there was NO rain. That dust turned the skies of Chicago and D.C. red all the way from the Texas panhandle and Colorado. Read up on it. So, too much can in fact also bad for any droplets forming never get large enough to even fall, there are too many tiny droplets instead of a less number of big ones heavy enough to drop. I wouldn’t blow off such a paper at first glance. (and I have not even read it yet, but have read some history)

November 14, 2011 4:17 am

Don’t oceans cover 75% of our planet? As such, the oceans would not qualify as dry regions. The net effect of increased aerosols over the planet would then have to be an increase in “rain, snowfall and the intensity of severe storms.”
John M Reynolds

Alan the Brit
November 14, 2011 4:21 am

a) It’s a model! Simulations, representations, & sophisticated, etc,
b) too many mays, cans, could be, etc, with just as likely may nots, can nots, & could nots etc!
Oh well I exepcet the cheque was in the post any how! 🙂

Bruce Catton fan
November 14, 2011 4:43 am

Don’t know how it affected rainfall amounts on the plains of Spain, but it was widely noted during the American Civil War that major battles — which filled the air with particulates — were frequently followed by major deluges.

mizimi
November 14, 2011 4:57 am

“Aerosol particles also affect the Earth’s surface temperature…….// Different processes MAY work in harmony or offset each other, leading to a complex yet INCONCLUSIVE interpretation of their long term net effect”
In other words, the models do not tell us what the net effect is, or even if it is in one direction.
But if you give us more money we will do some more research.
Aerosols come from many natural sources..eg. pine trees emit terpenes which degrade into fine aerosols and increase local cloud formation over pine forests, and as mentioned above, open water also produces aerosols. Not to mention dust storms and pollen and so on. It would be interesting to be able to compare times of high human aerosol production ( ie. pre clean air act legislation) with this (statistically short) data sample.

Bruce Cobb
November 14, 2011 4:58 am

“Increases in manufacturing, building of power plants and other industrial developments are often accompanied with increases in pollution whose adverse impacts on weather and climate, as revealed in this study, can undercut economic gains,” he stresses.”
This shows the agenda of the Watermelons. They are anti-development and anti-energy. Notice the wiggle word “often”. The supreme irony is that their very own anti-carbon policies have simply forced many industries to China and other developing countries, where pollution controls are far less stringent. Only in the land of Water (melon) World are all power plants and industrial devolpments the same worldwide, no matter what country they are in.

Gail Combs
November 14, 2011 5:20 am

Gary Mount says:
November 14, 2011 at 12:33 am
Why is it that any study that shows warming or alarmism only needs 10 years of data, but if it shows cooling or non alarmism 10 years isn’t good enough and 17 years is required.
At least this study says biofuels aren’t going to make a bit of difference (same pollution as any other carbon based fuel).
_____________________________________
Darn you beat me to it.
Why is 10 years good enough??? Because they used COMPUTER MODELS! Oh and also because they need the study for added ammo at Durbin since Kyoto Protocol ends December 2011.

Anthea Collins
November 14, 2011 5:27 am

That chap from Botswana was right. Years ago, before stubble-burning was made illegal (in UK), I was crossing Salisbury Plain, where stubble-burning was in progress. A|t the top of each column of smoke clouds were forming, some of them big, and very stormy-looking. Just an observation, no modelling, so no funding.
Anthea

Owen
November 14, 2011 5:33 am

I don’t remember these impacts in the 60’s and 70’s when I was growing up. In fact I remember pretty good growing seasons with adequate rainfall and a kind of hazy brownish blue sky from all the aerosols . I think someone is experiencing a very large case of expectation bias in this study, otherwise known as “I programed a computer to find what I wanted it to find!”

beng
November 14, 2011 5:36 am

*****
Increases in air pollution and other particulate matter in the atmosphere can strongly affect cloud development in ways that reduce precipitation in dry regions or seasons, while increasing rain, snowfall and the intensity of severe storms in wet regions or seasons, says a new study by a University of Maryland-led team of researchers.
*****
The presence/absence of water does that anyway, on land at least. Wet regions evaporate water into vapor, which is lighter than typical air. Dry areas don’t evaporate as much. So wet areas favor upward convection (& resulting precip) at the expense of adjacent dry regions where sinking air is favored — adjacent wet & dry areas tend to reinforce each other. Tropical storms can disrupt the effect, tho.
You don’t need “Increases in air pollution and other particulate matter in the atmosphere” to cause the “wet begets wet & dry begets dry” effect on land.

Gail Combs
November 14, 2011 5:44 am

No one has mention the major forest fires caused by the watermelons banning of “Controlled” burning and brush clearance.
Heck the fire smoke here in mid North Carolina was so bad all summer, I had a chronic eye inflammation yet we had a six week or more drought and the corn burned up. It never got more than knee high and then turned brown.
Think of all the BIG forest fires that have made the news: Russia, Australia, USA, Brazil, Canada…
Wildfires In South America Lead To Carbon Monoxide Over Australia: http://www.sciencedaily.com/releases/2007/05/070509081650.htm
List of Wild Fires: http://en.wikipedia.org/wiki/List_of_wildfires
The USA had a Dust bowl BEFORE we became really industrialized. Yet we did not have one in the fifties and sixties. Since the 1970’s we have cleaned up our act. The worst thing we ever did is ship out manufacturing overseas and you can thank Clinton for that.
This paper is just another example of politically skewed science used to make Humans look EVIL and guilt us back into the 18th century.

November 14, 2011 5:50 am

The truth is that “greenhouse gases” are just the more infrared-active gases, which means they shift the atmospheric heat transfer (which includes convection and conduction, not just radiation) more towards radiation (which is faster than conduction and convection), thus improving (never trapping or slowing) the rate of heat transfer–without changing the equilibrium vertical temperature distribution (which is governed by gravitational compression of the atmosphere, and by the incident solar infrared irradiation that directly heats the atmosphere). This is the fundamental physics that all of the “experts” are insulted by, because it wipes out their carefully concocted radiative heat transfer theory, and the consensus that so many have bought into and now consider their life’s work. But their life’s work will just have to change, to acknowledge the reality that there is no greenhouse effect, of increasing temperature with increasing carbon dioxide. The Standard Atmosphere, studied since the 19th century, adopted by the U.S. around 1920, and virtually unchanged since 1922 (the 1922 and 1976 versions are essentially the same, throughout the troposphere) shows the undeniable equilibrium state of the troposphere, and the reality of that equilibrium state should have prevented the “runaway climate” paradigm of the current consensus from ever developing–if evidence of seemingly catastrophic earth changes (such as the divisions between geologic “eras”, then the idea of a global “ice age”, then that of regularly recurring “ice ages”, then continental drift and its “explanation” by plate tectonics, and Milankovitch theory to “explain” the “ice ages”)–if all these had not made runaway climate an unavoidable, and irresistable, idea to an ever more degenerated scientific consensus. It is a very deep hole of false scientific theories, that few (and no academics that I know of) are willing to face.

higley7
November 14, 2011 5:55 am

Back in the late 1960s on the Jersey shore, it was quite clear that air pollution affected the weather. One summer we had 10 rainy weekends on a row, that I counted, with no weekday rain. It was clear that particulates, which cause or allow nucleation, would build up during the course of the week and regularly lead to rain, probably at some sort of threshold level, on the weekends. That pattern disappeared after the Clean Air Act went into effect.
I believe that it is a mistake to pretend that particulates today are as bad as they were then. This would lead to an over-reaction to this kind of news.

higley7
November 14, 2011 6:00 am

Do they also ignore the fact that no aerosols would be a very bad thing? No nucleation, 100% humidity (very oppressive), no evaporation, no evaporative cooling, it gets warmer.
Wait, what’s that? We do not transfer heat to altitude as efficiently and we warm. Soooo, low or no aerosols would be BAD.

Pamela Gray
November 14, 2011 6:03 am

I want error bands and a control (IE another 10 year period) for comparison. Then I want another set of researchers to choose a different 10 year period along with a different 10 year control period and in a different country. And I want folks to understand that we have less US pollution in our air than we did decades ago. So we should be seeing LESS affects now than back then if their suggested hypothesis holds water.

Zac
November 14, 2011 6:06 am

Why no mention of pollen, volcanoes and deserts as sources of aerosols?
It is not uncommon in the UK to have rain containing fine sand from the Sahara or fine ash from Iceland and for six months of the year asthma sufferers monitor the pollen count.

DirkH
November 14, 2011 6:10 am

“Understanding interactions across clouds, aerosols, and precipitation is one of the grand challenges for climate research in the decade ahead, as identified in a recent major world climate conference. ”
So they don’t have a clue? Thought so.

John
November 14, 2011 6:20 am

This may be a perfectly accurate study, but it seems to me that the normal and appropriate skepticism – in the best sense of the word, waiting to see if there is confirmation by other groups using somewhat different methods – is somewhat missing here.

FredericM
November 14, 2011 6:23 am

“from their marketing department?” Yes, it is a marketing department.
Experts say could. Expert said maybe. Experts are therefor truth providers. When asked of a politician what-who are the experts, the consensus is well funded.
In California the government system is well rehearsed – hire a person dedicated to writing a grant request. Private for profit entities(private timber vs U.S.F.S.) used heavy ink and the app would sand-screen to the round-file. The beginning of this expertise had ups and downs but in time the ‘writer’ would and did report ‘see, I have gleaned $10 of material from the grant giver, and it only took two minutes of my time equalling $7.50 for labor’. Being present for the carbon war prior to 9-11, this escalated to the tenth degree with the creation of DHS. In post 9-11 California all Expert-agencies have grant writers. In some part State governments near insolvency have utilized the Grant as one food staple to operations.
So, some experts have established that there is a reverse-slinky, not only will it use gravity to mot-ate downward but this new one will reverse with stored energy and escalate up. Barf is better receptical-ed in a disposable semi organic natural synthetic bag, buckets need to be cleansed. Dog gone it, Mikhail Gorbachev was my first Russian that made cents. Now, he was a plug nickle, shoot.

November 14, 2011 6:30 am

“Don’t oceans cover 75% of our planet? As such, the oceans would not qualify as dry regions. The net effect of increased aerosols over the planet would then have to be an increase in “rain, snowfall and the intensity of severe storms.”
John M Reynolds”
Kinda makes land use change seem more important.

mizimi
November 14, 2011 6:39 am

Looked at UM’s site which only gives an overview of the paper, and GeoScience is paywalled. So there is no way to ascertain what the detail of this paper is about ( ie. aerosol type discrimination and variation measurements) and what timespan ( datewise) is involved.
There is an interesting summary of the problems associated with aerosol measurement at Wiki.esipfed.org — “Satellite Measurements of Atmospheric Aerosols” .

November 14, 2011 6:40 am

There we go with the decade-long data sets again.

UK Sceptic
November 14, 2011 6:47 am

And when we asked them where the empirical evidence was only the crickets answered…

November 14, 2011 6:56 am

lol, the old ten year data = long term predictions. …… see it all the time. Funny stuff. Maybe Tanya Tucker knew what she was talking about after all….. (Lizzy and the Rainman) 🙂

Mike Smith
November 14, 2011 7:09 am

Well, there a lots of reasons to support reductions in particulate pollution that have nothing to do with climate. The adverse impact of particulate pollution on human health is large and well established.
We can’t do much about the production of volcanic ash but there are good reasons to reduce avoidable soot and other discharges in populated areas. Smog, asthma, and lung disease are not pleasant for anyone.
Let’s keep all that in mind even if this is just a blatant and shallow attempt to raise grant funds by tying the issue to the GW bandwagon and prophecies of doom.

G. Karst
November 14, 2011 7:16 am

Damn increased rainfall!
Why is it, that whenever alarmists speak of increased rainfall (whether from warm increased evaporation or increased aerosols), it ALWAYS is predicted to fall in areas that are already receiving too much rain (therefore disastrous)?!. It is 100% certain that rain will not fall on parched areas of the globe!
I find this assumed fact “alarming”. How exactly does increased rain/moisture “know” where it must fall and where it must NOT fall?? Warmer temps and increased moisture USED TO BE celebrated by the pagans. More than one virgin has been sacrificed, in order, to bring such conditions about. Seems most primitives, have a better understanding, of what makes the world thrive, than modern man. Why is that? GK

Olen
November 14, 2011 7:18 am

The direction of the study is clearly indicated by the list of sponsors.
If the mechanisms of some of the effects are uncertain how are there well defined relationships? It seems to a casual observer that all they are saying is that wet areas are wetter and dry areas are dryer because of particles in the air.
And who has proven that greenhouse gasses and aerosols are major agents dictating climate change or that there is such a thing as manmade climate change. If they are going to hang the purpose of their research on causes of manmade climate change should they first prove that manmade climate change as they define it exists?

Latitude
November 14, 2011 7:28 am

“Using a 10-year dataset”
============================
What 10 year dataset?
The one with a strong El Nino? La Nina?
The one where temps were going up? or the one where temps are going down?

TomRude
November 14, 2011 7:33 am

“Greenhouse gases and aerosol particles are two major agents dictating climate change.”
The End

Gary Pearse
November 14, 2011 7:50 am

So CO2 is a smaller than we thought effect – this seems to be the trend since climategate. Sensitivity has declined from as high as 5 to something less than 1. They claim to now know how much weight to give to the aerosol effect on climate – so how much is it percentagewise. Do I have a sensitivity of 0.5?

joe
November 14, 2011 7:55 am

eh, i don’t believe this either….what they want is to regulate business at every opportunity and also they have in mind the usual formula: scare story = big grant $$$

Steve In S.C.
November 14, 2011 8:08 am

This smacks of “Acid Rain”.

davidgmills
November 14, 2011 8:11 am

As a non-scientist, I am so tired of everything in science appearing to come up with an answer that is what the funders of the scientific research want. It just seems like scientists have no conscience. In this day and age of crony-capitalism, it just seems like all scientific research is prescribed. Some interested party with huge political clout lobbies the government to come up with an answer that is in the best interest of the interested party.
What I want to know is when will scientists regain the integrity they once had? When will they stop appearing to be so bought and paid for? I guess only when political and big business funding are out of the equation.

R. Gates
November 14, 2011 8:35 am

So the idea that the increases in aerosols over the past decade, from both anthropogenic as well as natural sources could have played a role in flattening the rise in global temps gains another set of data as evidence. This rise in aerosols, combined with a quiet sun, certainly must be considered as plausible reasons for the flattening of global temps. One would have to wonder what the effects would be with CO2 at 280 ppm.
REPLY: The study doesn’t say that, as it is limited to effects on rainfall patterns. But if there is an effect as you (and others tryign to find an explanation for the pause) suggest, then it shows that O2 isn’t all that strong and other factors can easily squelch its effects. It also demonstrates then that the whole “weather is getting more severe due to CO2 induced heating” is the ridiculous claim we know it to be. – Anthony

DirkH
November 14, 2011 8:49 am

davidgmills says:
November 14, 2011 at 8:11 am
“What I want to know is when will scientists regain the integrity they once had?”
You are overgeneralizing. LOTS of scientists are very aware of what’s going on, and don’t mince their words, even in arch-Green Germany.
http://notrickszone.com/2011/11/13/german-professor-slams-global-warming-science-calls-manns-hockey-stick-a-very-very-nasty-fabrication/

Latitude
November 14, 2011 8:56 am

R. Gates says:
November 14, 2011 at 8:35 am
One would have to wonder what the effects would be with CO2 at 280 ppm.
========================================
It can’t be much at all…
Otherwise when any thing caused it to pause, or decrease, when that was removed…
….temps would jump up severely to go back to the same original slope
As it is, the slope just starts over

November 14, 2011 9:07 am

I agree with the critical comments about length of record and limitations of models. There’s an inherent contradiction when Tony Busalacchi says, “Understanding interactions across clouds, aerosols, and precipitation is one of the grand challenges for climate research in the decade ahead, as identified in a recent major world climate conference” and the results of this study. If the interactions are “grand challenges”, what is the basis for the models?
Claims that this is new research is simply incorrect. I suggest they investigate the Laporte weather anomaly reported by S.A.Changnon Jr in the early 1970s.
http://www.straightdope.com/columns/read/144/do-big-cities-make-the-weather-worse
Or the doctoral thesis of Dr Bruce Atkinson that looked at increased precipitation effects around the London England urban heat island.
http://www.geog.qmul.ac.uk/staff/atkinsonb.html
They should also look at extensive research and practical application on cloud seeding to increase rainfall, as in the US and the former Soviet Union, or for hail suppression as in Penhold Alberta Canada in the1970s and 80s. The latter was abandoned primarily because of inconclusive results. More recently insurance companies in Calgary paid millions to a private company to seed clouds to reduce potential hail insurance claims. To my knowledge it was abandoned after no effective results – something I warned them about. A major problem is you have no reference point. You don’t know how much it would have rained if you hadn’t seeded.
Before Svensmark’s work was confirmed there were discrepancies between known condensation nuclei sources, water droplet formation and cloud cover. Did the authors consider variation in Cosmic ray created nuclei and cloud formation over the period of study?
I am concerned about the serious limitations of the study, but more about the need to justify the work by claiming it resolves planning and political problems. It’s a measure of the degree to which climate science has become politicized and driven by funding, which in turn is only granted to research that pushes the politically correct buttons. It is a vicious, non-scientific circle, which I also watched evolve. To illustrate the point I once proposed a need for funding to find the link between climate and AIDS since these were the biggest buttons for the government funding available to me at the time.

Bruce Cobb
November 14, 2011 9:13 am

Mike Smith says:
November 14, 2011 at 7:09 am
Well, there a lots of reasons to support reductions in particulate pollution that have nothing to do with climate. The adverse impact of particulate pollution on human health is large and well established.
Of course, but that’s a red herring. Carbonistas, when prompted, will claim to be interested in reducing actual pollutants as opposed to their targeted faux pollutant, “carbon”, but it’s a sham. The net effect of their very own anti-carbon policies has been to increase actual pollutants, and that effect will only increase unless they are shut down.

Julian Flood
November 14, 2011 9:24 am

John Marshall said November 14, 2011 at 1:30 am
quote
Not mentioned is the major source of aerosols- the ocean’s surface. But that would be omitted because fossil fuel burning is their target.
unquote
Just imagine what would happen if we could find a way of supressing the production of salt cloud condensation nuclei from the ocean’s surface. Even a minor reduction would have major warming effects, first on the sea temps and then — because there’s a paper which measured this and found that land temps follow sea temps — land warming.
Of course you wouldn’t get the tropospheric warming signal. And cloud cover reductions would occur.
Hmm. Surely there must be somethng that we could put on the oceans which would spread out to molecule-thin layers and do this. Ideas? Anyone?
JF

davidgmills
November 14, 2011 9:32 am

@ Joe: We have to get past this singular idea of governmental regulation being strictly the actions and desires of government. The real issue is not government versus the rest of us. The real issue is big government and big business in combination (call it crony capitalism) versus small business and individuals and what this combination of the “bigs” does to small business and individuals. We need to think of this issue in terms of big versus small, not in terms of government versus everyone else, or in terms of left versus right.
Most of what we call “excessive regulation” is the product of big business lobbying the “bought” politicians to regulate small business and individuals who can’t afford regulatory compliance. This kind of regulation puts small businesses and individuals out of business and leads to monopolies. Most “excessive regulation” is intentionally designed by big businesses who can afford the costs of regulation and take advantage of the costs of regulation. It gives big business plausible denial and the right to complain about government as well (while being secretly in support of it). Big business is really behind excessive regulation. Why? Big business can cope with the costs of regulation (and therefore imposes these costs on everyone who can’t) to force small business and individuals, who can’t cope with the costs, out of business.
The global warming scare is just a variation on the same old scheme of crony capitalism. Big business will gladly do whatever big governments require in terms of cutting CO2, as long as governments make cutting CO2 very expensive on the little guys. Publicly big business complains, but privately big business enjoys another monopolistic ploy.

davidgmills
November 14, 2011 9:41 am

@ DirkH. I am sure that lots of scientists complain, but their complaints sound hollow when they get paychecks from either government or from big business, both of which have vested interests in the outcome of scientific work. It is the appearance of impropriety due to the fact they are getting paid by an entity that has vested interests in the outcome of the scientific work. They just look like paid whores.
If scientists want to appear to have integrity and neutrality, scientists have to get off the government tit, and/or off the big business tit.

P Walker
November 14, 2011 9:59 am

” Different processes may work in harmony to offset each other , leading to a complex yet inconclusive interpretation of their long-term net effect . ” Well , that pretty much sums it up , doesn’t it ? Also , the last I heard , GHGs don’t prevent absorbed energy from being radiated as heat back into space , the key word being prevent . This is rubbish .

David Smith
November 14, 2011 10:08 am

The graphic which accompanies the news release includes a cloud labeled as “Storm” (upper right corner). I believe that is actually an image of a volcanic eruption, not a storm cloud.

Zac
November 14, 2011 10:14 am

Tell you what though, those thinking the air is bad these days would be shocked to see what it was like in the 50s and 60s.

Gail Combs
November 14, 2011 10:43 am

John says:
November 14, 2011 at 6:20 am
This may be a perfectly accurate study, but it seems to me that the normal and appropriate skepticism – in the best sense of the word, waiting to see if there is confirmation by other groups using somewhat different methods – is somewhat missing here.
_____________________________________________
You get numb to this crap after awhile.
It is not the study of rain vs aerosols that is the problem, it is the attempt to lay blame on humans when there are plenty of other sources of aerosols besides humans. It is also the “Computer Model SAYS” that is another big turn off.
As Mothusi Songa told The Botswana Gazette “Don’t you know that scientists lie a lot to make money?”
That growing attitude is the fallout from dishonest climate scientists. Scientists have broken faith with those who foot the bills and by continuing to write statements like:

….Together, they attest to the needs of tackling both climate and environmental changes that matter so much to our daily life,” says Maryland’s Li, who is also affiliated with Beijing Normal University.”
“Our findings have significant policy implications for sustainable development….

Where “sustainable development” is the code word for the United Nations Agenda 21.
Do not expect people to take this “Science” as anything but Political SPIN no matter how good the actual “science” may be.
It is Political Agenda driven “Science” no different than the crud churned out by Trofim Denisovich Lysenko.

November 14, 2011 10:56 am

“Increases in manufacturing, building of power plants and other industrial developments are often accompanied with increases in pollution whose adverse impacts on weather and climate, as revealed in this study, can undercut economic gains,” Zhanqing Li
It seems to me the take-away of this article is that we should never have survived the industrial revolution. All the drier areas should have turned to dust and blown away, and all the rainy areas should have flooded and washed away. Given that industrial development and building power plants has been causing such diminishing returns, I’d really like to know what has counteracted it? Anybody know? Why does industrialization still make people rich rather than kill us?
I also note that much of the data is from Oklahoma. The University of Oklahoma has one of the preeminent research facilities for such, and our local news has some of the best meteorologists in the world (except maybe for Chico). 😉 It strikes me that no Oklahoman’s are listed. Who knows our weather better than us? I also find it noteworthy that the 1930s are still the worst era for the south-central plains. We have also had worse floods in the past.
Mainly, as I said above and others commented also, 10 years of data? Give me a break.
I have an example of limited data. I did a lot of Charpy impact testing some years back, and that is a mess of a test. Hundreds of data points are required to minimize uncertainty for a complete transition curve. So how was I able to determine the curve from as few as five data points? First, the confidence was low with so little data, but 10-12 data points gave confidence under most circumstances. The key is that metals are well behaved, and prior knowledge of the material being tested can give you a very good guess before you begin. If you can hit the upper shelf, lower shelf, and somewhere on the transition with your first three or four samples, you can increase confidence with the remaining samples. Of course, if you miss and cannot define at least one point on each of the three regions before you run out of equivalent samples, then you are SOL. That set is a bust. You through that curve out and admit the error. We even developed finite element models, and these worked well, but so much had to be known before you could run the programs. The models helped extend knowledge. They could not create it.

Gail Combs
November 14, 2011 11:05 am

#
#
Mike Smith says:
November 14, 2011 at 7:09 am
Well, there a lots of reasons to support reductions in particulate pollution that have nothing to do with climate. The adverse impact of particulate pollution on human health is large and well established.
We can’t do much about the production of volcanic ash but there are good reasons to reduce avoidable soot and other discharges in populated areas. Smog, asthma, and lung disease are not pleasant for anyone…..
_____________________________________
The EPA is right on it. They are looking at regulating farm dust and the DOT is planning on reclassifying farm equipment so all farmers and workers must have commercial drivers licenses and comply with all the paperwork.
I really need to get my greenhouse built….

November 14, 2011 12:51 pm

Mike Jonas, please define “that”.
OK, no joke, are we to die to give the models a chance?

Graeme No.3
November 14, 2011 1:06 pm

The main purpose of this whole (or holed) study is to give an “explanation” for the failure of the IPCC predictions. They will say “we were right about warming from carbon dioxide, but aerosols operate in the reverse direction reducing the apparent impact”.
Saves face, and keeps the whole scare (and money supply) going for a few more years.

November 14, 2011 3:06 pm

Holy cow a study based on 10 whole years of data, and a computer model of clouds when we don’t even know if clouds have a cooling or warming effect, I sure there is no way this study could be wrong.

Cliff Maurer
November 14, 2011 3:56 pm

The study is one of many built on field studies under NASA, NOAA and the NSF since 2004. The most important was the Maldives Autonomous Campaign (MAC), a field study of the contribution of light-absorbing and light-scattering aerosols in atmospheric brown clouds (ABCs) to atmospheric solar heating and surface cooling on a synoptic scale.
In 2007 Ramanathan reported (Nature 448, 575–578):-
“… the recently observed widespread occurrence of vertically extended atmospheric brown clouds over the Indian Ocean and Asia, suggest that atmospheric brown clouds contribute as much as the recent increase in anthropogenic greenhouse gases to regional lower atmospheric warming trends.”
“We propose that the combined warming trend of 0.25K per decade may be sufficient to account for the observed retreat of the Himalayan glaciers.”
NASA intended to follow up using a aerosol polarimeter sensor on the Glory Mission, but this was frustrated by the launch failure.

November 14, 2011 4:29 pm

I found a link that gives quantification of the effects
The study found that under very dirty conditions, the mean cloud height of deep convective clouds is more than twice the mean height under crystal clean air conditions. “The probability of heavy rain is virtually doubled from clean to dirty conditions, while the chance of light rain is reduced by 50 percent,” says Maryland’s Li, who is also affiliated with Beijing Normal University.
http://www.sciencedaily.com/releases/2011/11/111113141304.htm
These are large effects. While, the effects themselves don’t surprise me, the size does.
FWIIW, I think this and similar aerosol studies are taking us closer to the point where the 0.7C rise in land surface temperatures since 1970 will be recognized as primarily an aerosol and aerosol seeded cloud effect, with GHGs playing a secondary role.

November 14, 2011 4:33 pm

Tim Ball has just about nailed it. As to particulates let me see, oh yes, smoke and clouds oh yes reflectors or maybe not. That translates to smoke and mirrors. That equates to politicians not scientists or maybe it is scientists studying, modeling if you will, being politicians.

November 14, 2011 7:37 pm

About the Dust Bowl, there was rain, snow and even floods. In the winter and spring.
Volcanic activity was way above normal. But you cannot prove it now with the Global Volcanism Program because they have cut the numbers of both the volcano counts and VEI by a substantial amount. Nearly in half for some years in that decade.
???????????

Brian H
November 15, 2011 2:47 am

And here I thought that the cleaning up of the atmosphere that occurred over the last few decades was allowing more sunlight through and causing warming!

George E. Smith;
November 15, 2011 12:38 pm

“”””” Rising air pollution worsens drought, “””””
Izzat “rising” air pollution; of maybe “increasing” air pollution ??
Why would it matter whether the pollution rises, or falls to the ground, like acid rain for example ??

Jay Davis
November 15, 2011 6:37 pm

Two comments. First, anything related to climate change coming from the University of Maryland is highly suspect, given their dependence on State funding. The Maryland Governor’s “green” initiatives practically ensure any study done by this university will be AGW alarmist in nature. Second, if these aerosols do cause what this study claims, then there should be some real exciting weather downwind (that is East, for the most part) of China and India. Is there?