Cleaner air may result in increased solar insolation and therefore warming.

So have particulates over Europe actually increased since the 1970s? Let’s see some figures. I think the opposite is true.
Those who argue that particulates are masking warming need to explain why there is more warming since 1980 in the Northern hemisphere (lots of partculates) than in the Southern hemisphere (low particulates). If the particulates theory is viable, there would need to be obsevable regional effects.

“48 research institutes” – I read that as 48 research prostitutes.

China is polluting today as much as the US did in the 70s.

They sound like Pachauri, or at least rhyme with it. Fishy!!!

Recyclable saying, already proven suitable for many environmentalist endeavors with many more potential usages already in progress:
We have done such a great job,
We are completely screwed!

New research initiated jointly by NUI Galway and the University of Helsinki reveals the true rate of greenhouse gas induced global warming has been masked by atmospheric aerosols (otherwise known as Particulate Matter), through their formation of reflective haze and cloud layers leading to an aerosol cooling effect.
The new investigations show that the present-day aerosol cooling effect will be strongly reduced by 2030 as more stringent air pollution abatements are implemented both worldwide and at the European scale and as advanced environmental technologies are utilized.”
So what they are saying is rampant environmentalism causes global warming? I always knew those fellows at GreenPeace were up to something, but really, the subtly of the plan astounds me. /sarc

Al Gore…man’s a complete ‘aerosol’.

The aerosol theory of cooling is wrong. Cooling was the strongest in mid to polar latitudes (as was the warming before and after) where sun does not shine that much, and especially in winters when it does not matter. The clue is on the oceans and their warm and cool cycles.

Braddles;
Isn’t he reason there’s been more warming in the 1980s in the Northern Hemisphere, because there’s been more burning of wood and other biomass from China, India and Indonesia over that time?
The Asian brown cloud was ever-present year after year, while the Indonesians burnt the rainforests to make way for the palm oil plantations to feed the demand for palm oil from Europe.
Brazil was burning the rainforests , during the same period to plant soy crops etc, and it still is, but that produced less soot.
There doesn’t seem to be any mention of black carbon in the story of this research, —although they did mention aerosols from burning of biomass from China, India, Brazil etc, but seemingly in the context of cooling aerosols.
The thing is, NASA research [ Dr Drew Shindell and others, including James Hansen ], has concluded that ~50% of the Arctic, glacier and permafrost warming is from black carbon—and they testified to Congress on that and on the urgency of mitigation of that
http://www.igsd.org/documents/PR_JacobsonBCstudy_29July2010_000.pdf
The advice:
[ “We will have very little leverage over climate in the next couple of decades if we’re just looking at carbon dioxide,” Shindell said. “If we want to try to stop the Arctic summer sea ice from melting completely over the next few decades, we’re much better off looking at aerosols and ozone.”]
So are these other researchers taking into account the warming aerosols , mitigation of which will stop some of the warming—or are they only taking into account the cooling aerosols, mitigation of which will have a net warming effect, and would be useful for warmists once again to say ‘it’s worse than we thought’?
I can’t understand why there’s so little written and spoken about the black carbon warming effect, when they’re obsessing about loss of the ice—-if they want to stop the melt.

So, essentially, now we should worry of the same emission polutants volcanoes spew out in the sea and air. But not only that, we’re supposed also paying for research that leads to us being able to control those emissions with political policies where EU is starring in a leading roll.
How is it that when a volcanoe blast stuff into the atmosphere it has to be of a certain magnitude to reach a global impact, but not so for the man made combustion engine who just has to idle to make acid rain on the other side of the planet?

2kevin says:
July 1, 2011 at 1:07 am
Is it just me, or is everything viewed as a no win situation by environmentalists? ))
Thats the problem with being part of a larger demographic phenomenom. The good ol Marxist Hippie trash of the 60’s & 70’s and their sycophants can only see the world through eye’s that were trained to hate the society they were raised in. Remember, these Eco clowns were the Uni students who on graduation took up work that was a continuation of their training. So they became the sociopaths that are demanding the whole world bend over or, the world will end in fire & brimstone. Standard religious ratbags. Nothing new here.
regards

David Suzuki was talking about global dimming quite a lot in the mid 1990s. This was one of the reasons I switched from being an alarmist to a skeptic. I wanted to know how much of the warming was due to reduced aerosols. The fact that the IPCC largely ignored this issue frustrated me at first. — John M Reynolds

Of course aerosols cause cooling, and of course that was the reason why some (a minority) in the 70s were predicting cooling. We’ve known of the cooling effect of aerosols for some time, though our ability to accurately measure their radiative forcing value is limited (Hansen has been pushing for a relatively inexpensive piece of satellite equipment that would do just that for more than 20 years). I thought the cooling effect of aerosols was well known by those who follow the climate issue. It is somewhat ironic that the success of the Clean Air Act was to remove much of the aerosol and particulate matter (ond ozone) pollution from the atmosphere. We knew both the cooling effect of aerosols and the warming effect of GHGs in the 1970s. The scientific debate then was over which would become a dominant forcing. By a 7-to-1 margin, peer reviewed articles from that decade which made a predicition one way or the other were predicting warming (a couple mainstream magazine covers notwithstanding). One of the proposed ‘fixes’ for AGW (short-sighted in my view) is to inject additional aerosols into the atmosphere).

Perhaps the use of electronic communications devices are now hiding the cooling..

Its frustrating, as a member of the ‘sceptic’ community, to write a whole book on this issue that so few people in this community appear to read! As far as I know, Anthony, you have never mentioned it! Any reasons? In ‘Chill: a reassessment of global warming theory’ you will find all of this rehearsed with full references to the peer-reviewed literature. You wonder whether the ‘dip’ from 1970 wasn’t created by aerosols….it was, but not by human sources as in the IPCC range of models (mostly sulphates) – see below:
yes, to Henry P. – there is clear evidence that the recent global warming is largely natural – and it comes from three papers in Science during 2005 (Wild, Pinker and Wielicki – referenced in Chill) which found:
* that ‘global dimming’ was truly global and occurred in pollution free zones such as the southern Pacific – this was later admitted in IPCC-2007, though well-buried, hence all the models that used anthropogenic sulphur to explain the dip were erroneous;
* the ‘brightening’ was also global and even occurred in China, despite the pollution there – and it began BEFORE the major initiatives to reduce sulphur emissions took effect…these were only ever of local significance in relation to atmospheric budgets – the brightening (increased insolation at the surface of the earth and oceans) occurred also in cloud-free measurements, hence indicating increased transparency of the atmosphere (there were also lower cloud levels…4% reducation from 1980-2000).
* sulphur abatement was in any case only regional, the emissions of Asia made up for the reductions in the West….global sulphur flatlines from 1980-2000, and in any case is it is emitted effectively at about 100m it is not likely to affect the relation of atmospheric/surface temperatures as in the case of a major volcanic eruption (as per the models).
The 1950-1980 ‘dip’ in global temperatures and the erroneous treatment in models represents a huge error on the part of ‘warmist’ thinking and modelling, yet it is effectively covered up…even more effectively when none of the critics reads the critical science!!!
You will find detailed analysis of the surface insolation data…due to lower reflective cloud cover and more transparent atmosphere, there was a roughly 4 watts/square metre excess Short Wave radiation running from 1980-2000 compared to 1 watt/square metre Long Wave computed for CO2. Being generous, the extra GHG could account for 20% of the warming – unless you argue that CO2 managed to thin the clouds as a feedback…which has been argued, despite the improbability. If that were the case, then post 2000 you would expect the trend to continue – it did not, cloud cover came back by 2%, ocean heat storage flatlined and so did sea-level rise.
And regarding the reason why the northern hemisphere heats up more than the south – that is also in the book: it is because 80% of global warming heat is held in the upper 200m of the ocean and then released to land…to be ‘held’ it has to be stored and this takes place in two major gyres in the north Atlantic and north Pacific…these are formed as the ocean’s coriolis force is constrained by the northern continents. In the souther hemisphere there is no such constraint and the circumpolar current dissipates the heat as it moves southward from the equatorial regions.
This heat storage is therefore not global, but regional. It is subject to long term cycles such as in the MWP/LIA dictated I suspect by the location of the jetstream, insulating cloud, and heat-extractive vortices (cyclones). The location of the jetstream is sensitive to the solar magnetic cycles as a proxy for UV output.
Carbon dioxide is, of course, a GHG and will contribute to these natural cycles but there is little empirical evidence that it amplified natural cycles in the Holocene, and no statistical treatement yet published to show that it did so during the glacial/deglacial episodes either – its effect is too weak. As we enter what may become the next Maunder Minimum (also treated in the book), CO2 ‘s weak effect might just save us from tipping into the next ice-age! But don’t try and tell Greenpeace!

Braddles says July 1, 2011 at 12:22 am ” If the particulates theory is viable, there would need to be obsevable regional effects.”
That assumes there is no rapid dispersal of the aerosols

The only problem with the theory that it was aerosols that led to the cooling seen in the 70’s is that the areas with the most aerosols did not see the greatest cooling.

Tony B (another one) says:
July 1, 2011 at 3:47 am
“gaken away”
Is that a British thing?

Here in the US, the something like 90% of the pollution has already been removed from the air. I suspect that Europe is similar. How much more reduction do they expect to get between now and 2030?

Good stuff, Peter Taylor.
Anthony, aerosols have always been the fudge factor and you’ve just tasted a perfected recipe.
=========================

@Anthony
“This makes me wonder if the temperature dip in the 1970′s where everyone was worried about global cooling wasn’t partially driven by atmospheric aerosols. With the advent of pollution controls, certainly we have cleaner (and more optically transparent) skies since then.”
I wrote the same thing here months ago except I phrased it more like:
If it weren’t for the environmentalist whackos ginning up an acid rain catastrophe back in the 1970’s we’d still be burning our fossil fuels as God intended with greenhouse CO2 accompanied by anti-greenhouse sulfate particulates which nullify the GHG component. But noooooo… those sulfate particulates were evil incarnate so now they are filtered out of smokestacks and tailpipes.

“This makes me wonder if the temperature dip in the 1970′s where everyone was worried about global cooling wasn’t partially driven by atmospheric aerosols. ”
I thought this was understood by all.
I worked in engineering on quite a few air, water and emissions cleanup for heavy industry, starting in 1972, just after the Clean Air Act and Clean Water Act were passed. Industry cried to high heaven that it made American industry non-competitive in the world marketplace. That may, in fact, have been true to some extent; it sure didn’t help. But what it DID do is clean up our then really dirty, polluted air.
When I heard (here on WUWT, probably) that that “pollution” was aerosols that have a cooling effect – perhaps 5 or more years ago – this quoted point seemed 100% an obvious explanation (though needing verification) for why the temps from about 1940 to 1970 were dropping. And why the temps since that time have been rising; The world was cleaning up its act.
I strongly suspect that Hansen recognized that this was a likely bet and built it into his reasoning when he claimed very early on that temps would be rising.
The post-WWII world ran on soft coal more than anything. Besides industry, I recall all the homes with coal furnaces. I played in one, even.
The air quality was TERRIBLE then. If the level of aerosols was proportional to the visible pollution, it certainly had to be a factor in reducing the solar insolation. It is good to see studies that can support this. It is certainly a factor that must be taken into account. Quantifying it would be a wise move, so our climate record has the proper adjustments being made.
It is simply amazing how many factors are not included in the AWG meme. Counter factors, that is. Any factor that supports it is touted to high heaven. All others are swept under the proverbial rug.

Mark Wilson says:
July 1, 2011 at 6:18 am
“The only problem with the theory that it was aerosols that led to the cooling seen in the 70′s is that the areas with the most aerosols did not see the greatest cooling.”
As I recall aerosols back then weren’t blamed for global cooling. Instead there was a scare ginned about the aerosols making rain more acidic which was going to destroy all the world’s forests in a few decades. As it turned out the acid rain was only a nuisance in the high industrial density northeastern US. Actual damage to forests was minimal and confined to the immediate area around huge emitters like Bethlehem Steel in Lackawanna, NY. Fifty miles from Lackawanna where I grew up there was no detectable effect from so-called acid rain. Nonetheless the federal government in and under the authority of the Clean Air Act of 1963 and later revisions forced all emitters large and small to scrub the sulfates out of smokestack and tailpipe emissions. Then the warming started a couple of decades later and we have another fine example of unintended consequences from environmental mania. The choicest one perhaps will forever remain the virtual castration of the nuclear power plant industry which could, if not for the environmentalist whackos, be providing enough power so we would have to import foreign oil. But noooooooooooo… nuclear power is another evil incarnate that could not be tolerated.

Since the 70’s farming practices in the US have changed substantially. There should be less particulate from farming because of chisel plowing rather than moldboard plowing, less cultivation and more use of herbicide, more drilling rather than rowing of soybeans, and generally faster operations in the spring.

AEROSOL COOLING : There is one notable test case – the one month grounding of aircraft in the US after 9/11.
A few years after the event I read that this lead to a 2 degrees C rise in temperatures over America. More recently I read that in fact it lead to a 1 degree rise in daytime temperatures and a 1 degee fall in nighttime temperatures.
The first story would give credence to the idea that aersols cause cooling.
The second story would suggest that although aerosols cause an effect, it is neutral overall – they may prevent some sunlight reaching Earth during the day, but also trap the heat overnight.
Can someone clarify what was actually discovered about this event?

Urban air is definitely cleaner than it was when I was a kid. You could see where cities were by the brown cloud overhead, and not just Denver, but smallish cities on the East Coast. This smog is long gone.
Maybe UHI is what is getting the shot in the arm? NAaah!

Mark Wilson says:
July 1, 2011 at 6:27 am
Tony B (another one) says:
July 1, 2011 at 3:47 am
“gaken away”
Is that a British thing?
*******************************
Nooooo, its an Apple thing.
Bloody ipad keyboard…….

“All these emission sources are expected to respond to climate change, although we are presently unable to gauge the strength of the multitude of feedback mechanisms involved. The uncertainties in feedback highlight the need for improved Earth System Climate models to encapsulate feedback processes generally lacking in current projections.”
Translation: “Our study concluded nothing and the clowns writing climate models are even more in the dark.”

The other interesting thing about the ’70s was that the amplitude of the sunspot cycle was about 50% of the two that preceded it, and the two that came after it (check out Anthony’s great solar reference page).

Peter Taylor says:
July 1, 2011 at 4:47 am
Its frustrating, as a member of the ‘sceptic’ community, to write a whole book on this issue that so few people in this community appear to read!
While I confess I haven’t purchased the book (sorry Peter), I would recommend for readers to check out Peter’s contributions to the debate via his website (and then purchase the book :->). As a dyed in the wool proponent and active campaigner of CAGW a few years back, Peter played a part in triggering my own AHA! experience. It can be extremely difficult for those who would class themselves as ‘progressives/on the left/liberals (in the American sense)’ to recognise confirmation bias when it comes to such a commanding shibboleth as AGW. Through Peter, who has been actively involved in many areas of environmental science, and others, I was able to question, for the first time, some of the tenets that had become a bedrock of my belief system.
Best wishes, Ian

CRS, Dr.P.H. @ July 1, 2011 at 9:04 am
As far as I’m aware, the consensus that you assert on the effects of various partially global clean air acts, is based on pure speculation. (unless you could perhaps refer to some empirical data). Regional considerations, increasing world population, and industrialization also complicate the issue.
Also, if you believe HadCru3 temperature records:
http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.gif
There was a bigger cooling period between ~1880 & ~1910, followed by a bigger pre WWII warming period than that recently.
Are you able to explain that too? Obviously there was no clean air act involved. Looks suspiciously like a predominant natural ~60-year cycle to me

As I understand the article, it is saying that aerosols (particulate matter) in the atmosphere over the past 30 years have caused the atmosphere to be cooler than it would be without them. Thus, part of the reason the measured surface air temperature is lower than model predictions is because they didn’t correctly take aerosols into account in models. And while they project an increase in temperature of 2 to 4 degrees in Europe as aerosols decrease, what they really mean that the DIFFERENCE between what the CO2 models predict and what the measured temperatures show will decrease by 2 to 4 degrees. It is not an increase of 2 to 4 degrees on top of the temperature predicted from CO2 increase.
In the U.S., aerosols have been decreasing steadily since the late 1960s. The recent trends in particulate concentrations in the U.S. are presented at this EPA site:
http://www.epa.gov/airtrends/pm.html
The EPA figures show a 27% decrease in national average atmospheric concentrations of PM2.5 (particles less than 2.5 microns in diameter) from 2000 to 2009, and a 38% decrease in PM10 (particles less than 10 microns, but greater than 2.5 microns in diameter) from 1990 to 2009.
It should also be noted that the national average concentrations of both PM2.5 and PM10 are below the National Ambient Air Quality Standards (NAAQS) for these pollutants during the entire period. So, over the past 20 years, even with low, and decreasing, aerosols in the U.S., the U.S. measured temperatures are still well below those predicted by the models

I don’t believe this idea that we are going to get warmer as we clean up the atmosphere although there is probably some truth in the idea that it was cooler when we had industrial smog before the 1950s ,at least locally.Some of us also worry about the effect soot pollution is having on the arctic ice extent which would get worse if we started drilling for oil in the arctic.I have not yet read Peter Taylor’s book but I intend to get it in the near future.

Mark Wilson says:
July 1, 2011 at 11:21 am
“The testing you are refering had to do with contrails from jet liners. Jet fuel has little to no sulfur in it.”
I don’t know where you get the idea that jet fuel has little to no sulphur in it. The limit is 3000ppm (0.3% by weight) for jet fuel. Compare this to the 15ppm limit for highway diesel in the U.S. Historically the limit was 0.5% for highway diesel which was lowered to 0.05% in 1993 and to 0.0015% in 2006. No such reductions were imposed for jet fuel. Your mileage may vary.

“This makes me wonder if the temperature dip in the 1970′s where everyone was worried about global cooling wasn’t partially driven by atmospheric aerosols.”
And the contribution that the sustained levels of GCR’s had on those aerosols.

Chris G @ July 2, 2011 at 2:52 pm wrote in part:

Wow, Watts is where Stephen Schneider was 40 years ago. Keep going, maybe you’ll catch up eventually.

Chris, I’m not sure what you are suggesting. Do you claim that the late Stephen Schneider was correct in his hypothesis 40 years ago?
Perhaps too, you could respond to a question I asked of a wise Dr above, in which he is tardy in clarification. I repeat it in full for your convenience and consideration:
CRS, Dr.P.H. @ July 1, 2011 at 9:04 am
As far as I’m aware, the consensus that you assert on the effects of various partially global clean air acts, is based on pure speculation. (unless you could perhaps refer to some empirical data). Regional considerations, increasing world population, and industrialization also complicate the issue.
Also, if you believe HadCru3 temperature records:
http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.gif
There was a bigger cooling period between ~1880 & ~1910, followed by a bigger pre WWII warming period than that recently.
Are you able to explain that too? Obviously there was no clean air act involved. Looks suspiciously like a predominant natural ~60-year cycle to me
Please feel free, either of you, to ask for aditional explanations if you no understand

Ed Mertin @ July 1, 2011 at 10:20 pm you wrote in part:

Two thirds of the volcanoes are in the northern hemisphere and only about one fifth are between 10°S and the South Pole.

Yebbut, the really really big ones have been down south, like Krakatau (1883) and Pinatubo (1991). But anyway it is just complicating noise, along with ENSO and stuff on top of the topic of this thread.
However, there are some interesting comparative considerations. Big volcanic eruptions eject particulates high into the atmosphere and it is generally agreed that they mix across both hemispheres because of their long suspension life. On the other hand, industrial particulates tend to have a short suspension life what with their modest max altitudes, and have rather regional effects predominantly in the NH (Northern Hemisphere) affected partly by wind patterns etc.
If you believe HadCru3 temperature records:
http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.gif
Perhaps you could gander at the differences between NH and SH?

kadaka;
nice commentary but … you embarrass me as a supporter when you demonstrate that you don’t know that one degree K is the same as one degree C. Only the zero points differ; the former is absolute zero, the second is water’s freezing point.
In the spirit of KISS, a rise of 1K is the same as a rise of 1°C. (And yes, the placement of the degree symbol is deliberate. A “Kelvin” is a degree Celsius. It’s a noun. A “Celsius” is meaningless, unless referring to a person. It’s an adjective, otherwise.)

Curious to see if, for example, there is a corelation in a world economic downturn realizing a hotter worldwide climate and economic uptake resulting in a cooler climate?

15 million and they still don’t get it.
The warming that has occured since 1970 is mostly in winter minimum temperatures and this is almost certainly an artifact of reduced near horizon particulate pollution from domestic burning of coal (and in some places peat).
The reason is simple. Daily minimum temperatures usually occur some time after dawn when solar heating exceeds radiative cooling. 50 years ago it would have been a morning ritual to light a coal fire around dawn in winter in a couple of hundred million households in Europe alone. Creating a thick smoke haze blocking early morning sunlight. Thus allowing longer for radiative cooling to exceed solar heating.
For those of you who have not seen an open hearth coal fire lit, it is an incredibly smokey operation.
Domestic burning of coal was progressively banned across Europe and elsewhere starting in the 1960s.

From Brian H on July 3, 2011 at 5:21 am:

kadaka;
nice commentary but … you embarrass me as a supporter when you demonstrate that you don’t know that one degree K is the same as one degree C. (…)

It’s not good to interchange them willy nilly even if 1K is the same increment as 1C but I sometimes do it when writing for a lay audience. In many cases you have to use Kelvin or you get wrong results. One particular case that comes to mind because I recently wrote about it is Carnot Efficiency of a heat engine which is expressed as E = 1 – Ta/Ti where Ti is the intake temperature in Kelvin and Ta is the ambient temperature in Kelvin. If you substitute degrees C you get ridiculously wrong answers.

HenryP
You mention that relative humidity has been on the rise in Tandil.
Low relative humidity is not what makes a desert have large day/night temperature swings. Low absolute humidity does that. Dew forms every night in a desert and most of the time that dew is the only source of water for the things that live there. By definition the relative humidity is 100% when dew forms. Low absolute humidity is what makes deserts heat up faster during the day and cool off faster at night.