Shocker: Global warming may simply be an artifact of clean air laws

Pollution controls have contributed to a more transparent atmosphere, thus allowing for “…a staggering increase in surface solar radiation of the order of ∼20% over the last decade.”

global-dimming-brightening
Figure 1 from Wild et al 2012 showing radiation balance differences due to aerosols

A new paper (O’Dowd et al.) from the National University of Ireland presented this summer at the 19th International Conference on Nucleation and Atmospheric Aerosols suggests that clean air laws put in place in the 1970’s and 80’s have resulted in an increase in sunlight impacting the surface of the Earth, and thus have increased surface temperatures as a result.  In one fell swoop, this can explain why surface temperature dipped in the 1970’s, prompting fears of an ice age, followed by concerns of global warming as the air got cleaner after pollution laws and controls were put in place.

WUWT covered a similar effort (Wild 2009) here and paper here (PDF 1.4 mb) which showed the issue but fell short of showing a provable causation for temperature.

Wild-2009-fig2

Now with this new effort by O’Dowd et al., it seems quite likely that cleaner air is in fact allowing in more solar radiation to the surface, and thus increasing surface temperatures by that increase of insolation.

Wild 2012, was a follow up, and figure 1 above is from that paper.

Martin Wild, 2012, Institute for Atmospheric and Climate Science, Zurich, Switzerland. Published in BAMS: Enlightening Global Dimming and Brightening

http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-11-00074.1 (open PDF)

Now with O’Dowd et al. and their findings, this “global brightening” as a climate driver is looking much more plausible.

The authors write in the new O’Dowd paper:

This study has demonstrated for the first time, using in-situ PM measurements, that reducing aerosol pollution is driving the Insolation Brightening phenomenon and that the trends in aerosol pollution, particularly for sulphate aerosol, is directly linked to anthropogenic emissions. Ultimately, the analysis demonstrates that clean air policies in developed regions such as Europe are driving brightening of the atmosphere and increasing the amount of global radiation reaching the Earth’s surface. The actual impact of cleaner air and insolation brightening on temperature remains to be elucidated.

And offer this graph:

Odowd-2013-sulphate-vs-insolation
Figure 1: (left) Nss sulphate PM10 mass concentrations measured at Mace Head from 2001-2011. (right) Surface solar radiation versus nss sulphate mass at Mace Head, 2003-2011

This is inline with Hatzianastassiou et al., 2012, Features and causes of recent surface solar radiation dimming and brightening patterns:

Surface incident solar radiation has been widely observed since the late 1950s. Such observations have suggested a widespread decrease between the 1950s and 1980s (“global dimming”) and a reverse brightening afterward.

http://adsabs.harvard.edu/abs/2012EGUGA..1413344H

The new O’Dowd paper:

Cleaner air: Brightening the pollution perspective?

AIP Conf. Proc. 1527, pp. 579-582; doi:http://dx.doi.org/10.1063/1.4803337 (4 pages)

NUCLEATION AND ATMOSPHERIC AEROSOLS: 19th International Conference
Date: 23–28 June 2013Location: Fort Collins, Colorado, USA

Abstract:

Clean-air policies in developing countries have resulted in reduced levels of anthropogenic atmospheric aerosol pollution. Reductions in aerosol pollution is thought to result in a reduction in haze and cloud layers, leading to an increase in the amount of solar radiation reaching the surface, and ultimately, an increase in surface temperatures. There have been many studies illustrating coherent relationships between surface solar radiation and temperature however, a direct link between aerosol emissions, concentrations, and surface radiation has not been demonstrated to date. Here, we illustrate a coherence between the trends of reducing anthropogenic aerosol emissions and concentrations, at the interface between the North-East Atlantic and western-Europe, leading to a staggering increase in surface solar radiation of the order of ∼20% over the last decade.

h/t to Sunshine Hours

It seems like a possible case of Occam’s Razor in action – the simplest explanation is the most likely.

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August 19, 2013 1:02 pm

If i get this right, industrial pollution masked the natural warming from the Little Ice Age and the clean air initiatives caused the earth temperatures to rebound to normal levels.
REPLY: Bingo. – Anthony

JimS
August 19, 2013 1:11 pm

Do ya think this will turn Al Gore, Michael Mann, and Jim Hansen into advocates of burning coal with high sulpher content? It would sure help Appalachia if they did, and kill the effects of bad ole CO2 in just one blow.

Joe
August 19, 2013 1:13 pm

Ok, so the world is happily warming out of the LIA at a fairly brisk but not worrying rate, then we get all industrial and start shutting out the sun. This is so effective that people start talking about a coming ice age.
Then we decide to clean up our act, and over the next couple of decades we get the gentle warming we would have anyway plus catch up on the bit we’d supressed, eading to all sorts of apocalyptic alarm bells. About 15 or 16 years ago the planet caught up and things have levelled out since.
Makes logical sense to me!

August 19, 2013 1:13 pm

That natural warming trend seen in the temp records as recovery from the LIA is so often dis-regarded. How many times do warmist types crow over record high temps. Or a record in record high temps. Record high temps would be expected with even with ZERO CO2 effects, through the oft forgotten natural warming trend we have enjoyed since the LIA.

Tom G(ologist)
August 19, 2013 1:17 pm

Sorry – too late. The science is settled. This window is closed.

Schrodinger's Cat
August 19, 2013 1:19 pm

I remember the “pea soupers”, very opaque smog (smoke plus fog) when even the ground at your feet was difficult to see. That was in the sixties, but apparently it was worse before then. I have not witnessed anything like that in recent decades.
I find this more believable than AGW due to GHG.

Peter Miller
August 19, 2013 1:23 pm

Seems to make a lot of sense, so the Global Warming Industry will do their very best to ensure this theory is stillborn.
C’mon trolls, do your best..

Schrodinger's Cat
August 19, 2013 1:24 pm

Joe makes a good point. In the seventies, climate scientists (including some of the same culprits), were warning of an imminent ice age. Then it started warming. It does fit.

Mikeyj
August 19, 2013 1:31 pm

Base on this theory Washington D.C. should be friggin freezing with all the crap being thrown into the air there.

MattN
August 19, 2013 1:32 pm

I remember this scenario being discussed years ago here at WUWT. Not sure how much I buy it. 20% is a whole lot.

Lance Wallace
August 19, 2013 1:41 pm

Today it’s hazy in Santa Rosa and the nearby mountains to the East are bluish and low-resolution, unlike their usual crisp definition. The light on my garden is diffuse and the temperature is about 10 F lower than yesterday. I began monitoring fine particle (PM2.5) levels in my back yard last week and after 5 or 6 consecutive days in the 1-5 ug/m3 region, today it is more like 50. So one can well believe in the effect of aerosols in reducing solar radiation.
Prevailing theory is that atmospheric nucleation is a ternary reaction process involving sulfuric acid (resulting from the sulfur dioxide produced in this country by the great power plants of the Midwest), ammonia (from feedlots, for example) and water vapor. While living in Virginia, I monitored ultrafine particles and could see the process begin between 10 AM and noon, reaching very high concentrations approaching 100,000 per cc, and then declining in the afternoon. These “nucleation bursts” covered enormous areas (thousands of square kilometers) and happened fairly often, several times a week in summer, somewhat less often in winter.
Moving to Santa Rosa last year, I did not expect to see them happening here, since the West doesn’t have much sulfuric acid in the atmosphere. However, I began monitoring UFP here last week and saw an increase up to 40,000/cc on one or two days last week. Maybe the nitric acid here can also participate in the nucleation process.
Unfortunately, ultrafine particles are not on the EPA’s radar, despite the evidence that they can produce severe oxidative stress and perhaps even broach the blood-brain barrier by using the olfactory channel, so very little monitoring of atmospheric levels is occurring, thus making it impossible to do epi studies linking concentrations with health effects. One such study occurred in Erfurt, formerly East Germany, where UFP monitoring occurred over several years and was sufficient to show that mortality from cardiorespiratory disease was significantly linked to UFP and NOT to fine particles (which is what is regulated in the US and Europe).
One wonders whether the increase in sulfur dioxide that will occur in Germany and China and India due to coal will be sufficient to roll back the general decrease that occurred in the 43 years since EPA was created. Perhaps not if good scrubbing techniques are employed.

Editor
August 19, 2013 1:42 pm

Count me out. This smells just like the claims that the ~1940-70 cooling was caused by (man-made, unmeasured) aerosols. This hypothesis only runs marginally OK from ~1940 onwards. It has no explanation for the ~1910-40 warming, or for the cooling before that. To me, it’s a non-starter.

LucioC
August 19, 2013 1:44 pm

If that is so, could the increasing aerosol pollution being produced by China be part of the reason for the “global warming” standstill occurring for the past decade or more?

policycritic
August 19, 2013 1:44 pm

Hahahahahahahaha. Blame Nixon.

AnonyMoose
August 19, 2013 1:45 pm

Jonas, look up “Little Ice Age”. You’ll better understand why it was warming in 1900.

Schrodinger's Cat
August 19, 2013 1:48 pm

I bet the BBC fails to mention this.

DCA
August 19, 2013 1:50 pm

Could the pause be the result of polution from China and India?
The warmists will probably say this even more reason to stop burning fossil fules.

John W
August 19, 2013 1:51 pm

Is this a peer review paper….? I could not tell from the link.
REPLY: yes, it is in the American Institute of Physics (AIP) website – Anthony

Tregonsee
August 19, 2013 1:56 pm

I am an unashamed Denier, but I have noticed two, somewhat contradictory streams in papers which are in disagreement with CAGW. Many are like this one, explaining the temperature increase in terms of something besides CO2 levels. In fact, there are multiple explanations which have appeared here. The other stream argues that there is little or no GW when questionable “adjustments” are taken out, proxies are fixed, etc. Bad physics and bad ideology are not mutually exclusive. Warmist theory predicts anything, but it seems we are suffering from an excess of explanations which predict the same thing.

Pamela Gray
August 19, 2013 1:59 pm

Count me out as well. Weather pattern variations can also account for the increase and decrease in aerosols. By FAR the most prevalent is soil and plant dust which has a pattern variation tied to periods of drought caused by weather pattern variation, the next is salty sea spray which is tied to winds, again caused by weather pattern variation. And then there are clouds driven away or allowed to stay depending on equatorial winds and humidity, again caused by weather pattern variation. Of the aerosols ascribed to human cause, the percent change of just those particles would not be capable of driving the temp trends. They are riding on the coattails of the big leagues.

toby52
August 19, 2013 2:02 pm

So John Tyndall was wrong, just like Darwin!

DirkH
August 19, 2013 2:04 pm

Tom G(ologist) says:
August 19, 2013 at 1:17 pm
“Sorry – too late. The science is settled. This window is closed.”
Just like Piltdown Man was finally recognized as a hoax, so will some day very soon the entire climate science since 1971 be discarded. And all the youngsters now studying climate science to become do nothing rent seekers will have to find a way to earn their bread.

John W
August 19, 2013 2:04 pm

Is this a peer review paper….? I could not tell from the link.
REPLY: yes, it is in the American Institute of Physics (AIP) website – Anthony
——–
Thanks!!….I used the wrong link

dp
August 19, 2013 2:05 pm

I mentioned this in a post here in the past year. Nice to see the obvious getting traction. It also proves the adage “No good deed goes unpunished”. “Be careful of what you wish for” comes to mind, too. My motivation was the realization that some of the Arctic warming (pools and similar effects of insolation) can be explained by cleaner air. Even with low slant angles, the effect of sunlight will be greater through cleaner air. Deductive reasoning, at best, certainly.

August 19, 2013 2:05 pm

Schrodinger’s Cat says at August 19, 2013 at 1:48 pm

I bet the BBC fails to mention this.

That has no significance.
They fail to report lots of things.
The number of unreal things the BBC fails to report is not greater than the number of real things.

August 19, 2013 2:06 pm

A similar paper using Netherlands data:
——
“Besides leading to a better visibility (a direct
aerosol effect), a decrease in aerosol concentration
might also lead to a reduction in
cloudiness (indirect aerosol effect). The sunshine
duration measurements1, which are
considered to be more accurate than cloud
cover estimates, can be used as a good
proxy of (daytime) cloudiness. The trends of
yearly average daily sunshine duration
(Figure 4), presented as a percentage of the
day length, in both De Bilt and Schiphol
show a similar pattern to the trends in high
visibility days, and are consistent with what
is expected from both the aerosol direct and
indirect effect. Since the early 1980s, the
sunshine frequency has increased by as
much as 25%.
This trend is, however, occurring almost
exclusively in summer: between 1985 and 2010,
the average value of the surface
global short-wave radiation in De Bilt in
summer has increased by more than
15Wm−2 (i.e. 0.6Wm−2yr−1). The average level
of the surface global short-wave radiation
in summer for this period is 194.7Wm−2,
compared with 188.7Wm−2 for the dimming
period between 1958 and 1983. The increase
during the brightening period is strongest
in the morning, between 0700 and 1000 UTC,
at more than 1.5Wm−2yr−1.”
http://sunshinehours.wordpress.com/2012/05/15/more-sunshine-in-the-netherlands/

Dave L
August 19, 2013 2:08 pm

So, in other words, the EPA is responsible for global warming. People are stupid.

DirkH
August 19, 2013 2:08 pm

Lance Wallace says:
August 19, 2013 at 1:41 pm
“One wonders whether the increase in sulfur dioxide that will occur in Germany and China and India due to coal will be sufficient to roll back the general decrease that occurred in the 43 years since EPA was created. Perhaps not if good scrubbing techniques are employed.”
Since about 1995 all German power plants burning brown coal have been fitted with flue gas scrubbers; with federal tax incentives; China still builds new coal power plants without. In the 90ies there was still the Waldsterben / Acid Rain hysteria raging in Germany so desulfurization was a top political theme.

Kasuha
August 19, 2013 2:10 pm

So the warming actually is manmade? Or rather man-cleaning-after-himself-made? That would be too much fun.
Cleaner air however also causes cleaner and more persistent snow in the winter (and in polar regions).

DirkH
August 19, 2013 2:13 pm

M Courtney says:
August 19, 2013 at 2:05 pm
“They fail to report lots of things.
The number of unreal things the BBC fails to report is not greater than the number of real things.”
But they never fail to lie about the things they report. (They are an EU medium and bound by EU law.)

Gail Combs
August 19, 2013 2:15 pm

Mikeyj says:
August 19, 2013 at 1:31 pm
Base on this theory Washington D.C. should be friggin freezing with all the crap being thrown into the air there.
>>>>>>>>>>>>>>>>
Well DC is certainly a bit on the cool side at 73.8 °F Normal is 86 °F and the MAX was 98 °F in 2002.
Mid North Carolina is even cooler at 72F (Summer what summer?)

Other_Andy
August 19, 2013 2:15 pm

Also wondering, as many stations are in or near cities\ airports, how this will affect UHI for weather stations.

Ray
August 19, 2013 2:16 pm

Schrodinger’s Cat says onAugust 19, 2013 at 1:24 pm :
“Joe makes a good point. In the seventies, climate scientists (including some of the same culprits), were warning of an imminent ice age. Then it started warming. It does fit.”
Do you suppose 17 year temperature plateau can be credited to China’s increasingly dirty air?

Erik Nobel
August 19, 2013 2:16 pm

thought for over 20 years now that this is the case .. that IF man has caused observable changes in the earth’s temperature .. it is these changes in aerosols .. also note we reduced black soot in North America and Europe .. yet China .. mostly .. and Russia have increased coal burning and black soot emissions since the 1990s .. and at a much faster rate since 2000 .. black soot may explain Northern Hemisphere ice melt trends better than temperature changes .. per Hansen, J., and L. Nazarenko (2004) Soot climate forcing via snow and ice albedos .. “The calculated global warming from soot in snow and ice, by itself in an 1880-2000 simulation, accounted for 25 percent of observed global warming” .. not that I totally buy the “25%” figure .. but that in itself is a larger effect that Gavin’s claimed 20% CO2 effect within the greenhouse gas category of effects on global temperature .. and changes in greenhouse gasses .. in my informed opinion .. do not have nearly the effect land use changes have had ..

Gail Combs
August 19, 2013 2:18 pm

Lance Wallace….
A friend in Alaska several years ago was complaining about the smog rolling in from China that was mucking up Alaska’s pristine clean air.

TomR,Worc,MA
August 19, 2013 2:21 pm

Peter Miller says:
August 19, 2013 at 1:23 pm
Seems to make a lot of sense, so the Global Warming Industry will do their very best to ensure this theory is stillborn.
C’mon trolls, do your best..
====================================
…….. unless they can figure a way to tax it …….. then they will be solidly behind it.

BBould
August 19, 2013 2:21 pm

I think its interesting. We should not categorically rule out anything until its proven to be false. Especially in climate science, something we truly know little about.

michael hart
August 19, 2013 2:24 pm

20% Would indeed be staggering. Like MattN, I’m not staggered yet.

Schrodinger's Cat
August 19, 2013 2:27 pm

I realise that many people are not old enough to have experienced smog. This is an attempt to explain what the smogs were like. Visibility would drop to a few feet and the best way I can think of it is very dirty fog.
Fog is normally a dispersion of water droplets in air and smoke is a dispersion of particulate solids in air. Smog is a combination of both, so it has a much lower transmission to light and so the sky appears much darker and the air more opaque.
The smogs in Glasgow and London and other major cities were pretty real and very spectacular. I expect US industrialised cities were even worse. Many people had serious breathing problems and lung conditions. Traffic would grind to a halt. Ships would be unable to navigate in rivers, ports or close to the coast. The pollution was not evident all of the time, but from time to time particular weather conditions would make the smog descend like an opaque curtain, reducing visibility to a few feet. Areas prone to mist, such as near rivers, would get badly affected.
Basically, the solid pollutants in the atmosphere would nucleate on dispersed water droplets and the result would be very dirty fog. Smokeless zones were introduced in the sixties and in time, this solved the problem.

Latitude
August 19, 2013 2:28 pm
Mike Haseler
August 19, 2013 2:32 pm

Been saying this for years. Like this in 2011 … “Like most UK sceptics I’ve written my fair share of complaints regarding BBC bias. But one person really does take the biscuit for their response. Richard Black wrote an article about Chinese pollution causing warming … he must also we aware that the wholesale cleaning of the air due to clean air acts in the the 1970s must have led to much larger warming.” Scottish Sceptic

August 19, 2013 2:32 pm

Logical enough but only as a modulating factor superimposed on natural variability.
Given the scale of the changes from MWP to LIA to date I don’t see the aerosol proposition as being significant.
It does, however seek to maintain the ‘our fault’ meme by replacing the CO2 scare with something else that was human generated.
Anyhow the improvements in developed nations would have been largely offset by deterioration in developing nations would they not?
And then again how to explain the global cloudiness changes between regimes of zonal jets and meridional jets which seem to correlate with changes in solar activity.
Gail correctly points out that natural variations in atmospheric opacity from wind borne sea spray and dust would be a far larger effect than our puny efforts.

TomR,Worc,MA
August 19, 2013 2:32 pm

DirkH says:
August 19, 2013 at 2:04 pm
………….
And all the youngsters now studying climate science to become do nothing rent seekers will have to find a way to earn their bread.
====================================
The phrase, “Would you like some fries with that ?”, pops into my mind for most of these jokers.

Joe
August 19, 2013 2:33 pm

TomR,Worc,MA says:
August 19, 2013 at 2:21 pm
…….. unless they can figure a way to tax it …….. then they will be solidly behind it.
————————————————————————————————
“Well done all you voters, between us we’ve really cleaned up the air throughout the Western World. Give yourselves a pat on the back and a tax increase”
Honestly, if the electorate let them get away with that one without glorious Revolution then they deserve to freeze in winter!

John West
August 19, 2013 2:34 pm

So, would one expect LH going from -3 to +3 to increase the relative humidity? Perhaps not. Considering there would also be isobaric heating which increases the saturation pressure thereby reducing the relative humidity. Hmmm. I’ll have to mull this over a bit more.

Editor
August 19, 2013 2:35 pm

What is certain is that air pollution was pretty significant back to the 19thC. This may have slowed down the LIA rebound, but does not explain the 1930-1950 warming.
REPLY: Remember the Great Depression of the 1930’s? Less GDP output, less energy used, less coal, etc. Wouldn’t it be wild if 1934, the hottest year in USA, was result of 1929 stock market crash and subsequent downsized GDP in the years following? – Anthony

August 19, 2013 2:35 pm

Sorry. Pamela not Gail.

Owen in GA
August 19, 2013 2:36 pm

This is fine to a point, but what would explain the decline between ~1878-~1910? Did we have a sudden increase in world-wide smog events during that period as well? It doesn’t seem to really explain things very well. Simplicity says it is likely a small warming recovery from the little ice age with ocean oscillation cycles thrown in on top of it. (What causes the ocean cycles or the periodic ice-age/recovery cycles for that matter – I haven’t seen a completely satisfying explanation of “why”, just the “what”)

BBould
August 19, 2013 2:38 pm

Schrodinger’s Cat – I remember it well from LA and Denver, as the Smog got better it turned into haze if my memory serves.

taxed
August 19, 2013 2:43 pm

Sunshinehours
That Netherlands data ties up with what l noticed about three years ago here in the UK.
That here in the UK since 1930, there has been a much stronger link to changes in the annal mean temps and changes to the annal sunshine hours. Then they has been to changes in CO2 levels. As the amounts of sunshine hours go up so the the temps seem to follow.

Owen in GA
August 19, 2013 2:47 pm

I remember the sky being a brownish-blue and wondered what it was that the old books talked about a vibrant blue sky. The Crayola “sky blue” crayon didn’t make sense to me as it didn’t have a brown tinge, Then the family went on vacation and drove through the mountains in Montana and I understood. The sky really was blue. By the time I graduated high school, the sky was pretty much that way everywhere. Then I joined the USAF and got assigned to Korea, and it was back to the brown sky again, especially in the winter with all the charcoal heating they used. I remember flying out and about 200 miles off shore, the color of the sky and sea went from a yellow-brown to a vibrant blue. Pollution can indeed be a problem.

Schrodinger's Cat
August 19, 2013 2:48 pm

I remember the smogs well and the paper being discussed seems quite credible to me in view of my personal experience of these events.. Smoke was probably a major factor at that time in the industrialised parts of the UK and probably elsewhere.
I just wish to make the point that I am not in a position to draw conclusions about the current lack of warming and the possible connection with pollution in China. I just do not have the data or personal observation on which to form an opinion either way.

John F. Hultquist
August 19, 2013 2:49 pm

Interesting.
Two articles for background reading (link follows quote):
# ONE:
The towns of Donora and Webster, Pennsylvania, along the Monongahela River southwest of Pittsburgh, were the site of a lethal air pollution disaster in late October 1948 . . .
http://www.pollutionissues.com/Co-Ea/Donora-Pennsylvania.html#b
# TWO:
The light-colored form of the moth, known as typica, was the predominant form in England prior to the beginning of the industrial revolution.
http://www.millerandlevine.com/km/evol/Moths/moths.html

Eugene WR Gallun
August 19, 2013 2:49 pm

Dave L 2:08 says
So, in other words, the EPA is responsible for global warming.
laughing out loud
Eugene WR Gallun

August 19, 2013 2:51 pm

“what would explain the decline between ~1878-~1910”
UK coal production went from 72 million tonnes in 1853/62 and peaked in 1903/12 at 258 million tonnes. and then down to 208 million tonnes by 1943/52.
https://www.gov.uk/government/statistical-data-sets/historical-coal-data-coal-production-availability-and-consumption-1853-to-2011

richardscourtney
August 19, 2013 2:52 pm

Friends:
A decade and more ago in posts on several blogs I wrote the following prediction.
The global climate cooled for ~30 years from ~1940 to about ~1970.
Alarmists then claimed the global cooling was caused by emissions of SO2 from power stations.
The global climate warmed for ~30 years from ~1970 to about ~2000.
By ~1980 the global cooling scare became untenable so the global cooling scare was morphed into the global warming scare.
Alarmists then claimed the global warming was caused by emissions of CO2 from power stations.
If the global climate cools for more than ~10 years then the global warming scare will probably be morphed back into a global cooling scare.

This prediction was ridiculed by warmunists whenever and wherever I made it.
Global warming has stalled for more than 16 years.
The subject of the paper reported in the above post is a suggestion that SO2 from power stations has caused global warming to stall.
I see no reason to change my prediction which I repeatedly made a decade and more ago.
Richard

Olaf Koenders
August 19, 2013 2:54 pm

It’s probably already been said, but I think solar and ocean cycles have far more to do with it than just clean air, as the MWP to the LIA will attest. It’s an idea, but that study on such a short time frame with many other factors not taken into account shouldn’t be taken too seriously.
As we know from many sources such as Vostok ice core data, since the end of the last deep ice age some 10kya, the planet’s been cooling gradually and can’t be due to just the air getting a bit dirtier.

Mr Bliss
August 19, 2013 3:07 pm

REPLY: yes, it is in the American Institute of Physics (AIP) website – Anthony
—–
It can only be a matter of time before the SKS boyz are in full rebuttal mode against this paper.
I predict a flurry of Guardian articles under the 97% banner – How long before resignations follow at the AIP?

Box of Rocks
August 19, 2013 3:15 pm

Global warming is the fault of the unwashed masses of mankind….
The science is settled.

Box of Rocks
August 19, 2013 3:18 pm

Owen in GA says:
August 19, 2013 at 2:47 pm
Remember when the sky was brown?
Ha, go to Denver and look down from Look Out Mountain, or out west by Leydon Junction/Rocky Flats or from Broomfield.
There exist a brown haze.

August 19, 2013 3:32 pm

This theory is far more convincing than the CAGW due to CO2 and other ‘greenhouse’ gases. However, first, I would like to check some temperature records that have not been surgically renovated to support the CAGW cause..

Gary in Ridgecrest, CA
August 19, 2013 3:32 pm

It’s just one more piece of the puzzle. It’s now the job of good climate scientists to put them together to show the whole picture. These silly warmists have a few pieces of the puzzle and have jammed them into some distorted version of the truth that suits them. They have a few pieces and refuse to look at the whole picture. Hopefully the capstone will be identified before too long.

Taphonomic
August 19, 2013 3:40 pm

Talk about unintended consequences!

george e. smith
August 19, 2013 3:41 pm

Well the general idea sounds plausible, including the possibility that Chinese (and apparently Indian) ramp up industrially, could be a cause of the present static condition.
I’m bothered by the 20% number.
A TSI number of 1362-6 (which used to be 1353) used to give a nominal 1,000 W/m^2 at the earth surface; this a result of blue sky scattering, plus atmospheric absorption; O3, H2O and CO2, plus “aerosols.”; which is about a 25% reduction.
A 20% increase would take us back to around 1,200 W/m^2 at the surface, and I haven’t heard of any solar energy companies using a value like that recently.
But in California, which historically has had real smog conditions, we supposedly have cleaned up our air (on average) so it is now cleaner than when the first covered wagons rolled across the borders. Now nobody in LA would believe that; but they are in LA, which should tell us something about them.
I’m not in the Occam’s razor fan club. Einstein, also told us that scientific theories should be as simple as possible; BUT no simpler !
A full analysis of all that is going on climate wise; well at least Temperature wise, is still a very complicated set of interractions; so I wouldn’t describe it as a simple problem, or solution.
But I can generally be persuaded, that processes which ALTER THE GROUND LEVEL SOLAR INSOLATION, are considerably more likely to explain climatic Temperature changes, than any GHG diddling with outgoing LWIR radiation. Yes that would include cloud feedback.
Yes I do accept that GHGs interfere with LWIR escape. I just don’t see any plausible mechanism, for that to return significant “heat” energy to the surface.

August 19, 2013 3:43 pm

If this were the case, wouldn’t we expect cooling (or at least much less warming) in those regions of the world where aerosol depth has continued to increase (e.g. India or China)?
Seems not to be the case in practice:
http://berkeleyearth.lbl.gov/regions/india
http://berkeleyearth.lbl.gov/regions/china
Also, its worth pointing out that GCMs have long incorporated both direct and indirect aerosol forcing, so I’m not really sure how new this is…

Another Gareth
August 19, 2013 3:46 pm

Mike Jonas said:
“Count me out. This smells just like the claims that the ~1940-70 cooling was caused by (man-made, unmeasured) aerosols. This hypothesis only runs marginally OK from ~1940 onwards. It has no explanation for the ~1910-40 warming, or for the cooling before that. To me, it’s a non-starter.”
The rolling out of electric might fit with the pre-1940s warming. Cleaner fuels and more centralised energy generation leading to less pollution perhaps.

Henry Clark
August 19, 2013 3:47 pm

An increase in solar radiation reaching the surface did occur over 1980s-2000 as implied, especially with fewer shading clouds than during the global cooling scare period before it. However, given how much there is a match of five peaks and five troughs in sea level rise rates, humidity, cloud cover, and temperature with forcing from cosmic ray flux over the 1960s-2000s period of neutron monitor data as illustrated in http://s24.postimg.org/rbbws9o85/overview.gif (with reference links given: enlarging on further click), variation in human aerosol emissions would be supplemental to that, not the only factor. While I haven’t cross-checked the Wild global dimming/brightening article’s figures, likely it is basically right in what it says, just not including the bigger picture, making it the truth but not the whole truth.

Paul Linsay
August 19, 2013 3:49 pm

What about the Southern Hemisphere which is mostly ocean? I’m under the impression that the pollution from the NH has a hard time migrating across the equator.

Latitude
August 19, 2013 3:52 pm

Mace Head from 2001-2011. ………… at Mace Head, 2003-2011
But global temps went down from 2001-2011

george e. smith
August 19, 2013 3:56 pm

I also see an obvious error in the balance cartoons. If the LW up goes from +1 up to +2, the LW down, should only go from +2, up to +2.5, not to +3, because the re-emission from the atmosphere has to be isotropic, so only half of it can come down, the rest goes up.
I’m not a particular fan of that diagram representation anyway.

son of mulder
August 19, 2013 3:56 pm

Empirically speaking, I remember discussing with my wife, way back in the early 80’s, how we both felt the sun seemed warmer on the skin than it had used to. So I’m not surprised by this paper.

michael hammer
August 19, 2013 4:00 pm

The surface currently receives 243 watts/sqM on average. 20% increase would amount to an extra 48 watts/sqM. Just based on the stefan boltzman law that would equate to about 12C rise, significantly more if one takes into account cloud and ghg effects. If true it would imply negative feedback strong enough to reduces 12C to about 0.5C (assuming all the “adjustments” are justified). Even accepting that negative feedback is highly likely, that’s pretty strong negative feedback.
Now where has this extra energy come from. Is it energy which was previously reflected back out to space. If so the change implies a change in albedo from 0.3 to about 0.15. Since we monitor albedo from space I find it exceptionally implausible that such a huge change would not have been observed.
Is it energy previously absorbed by the atmosphere. If so it is still energy injected into the biosphere so overall it may not have all that much effect. However reducing the energy injected directly into the atmosphere by a massive 48 watts/sqM (and it is truly massive) should have had very noticeable effects such as cooling of the atmosphere, a change in the apparent lapse rate or substantial change in height of the tropopause etc. None of these seem to have been reported.
To put it in perspective, the generally agreed direct impact of doubling CO2 is about 3 watts/sqM so this is something like 16 times larger. If doubling CO2 could have any noticeable effect this should be a standout red flag no one could miss, even with crude instruments.
The concept in principle seems quite plausible but the magnitude claimed seems grossly implausible. But then isn’t that the issue with essentially all of climate science today. After all the whole issue with CAGW is not whether its wrong in principle but rather whether the effect is 3C or 0.3C

Ken B
August 19, 2013 4:02 pm

This is something that I have tried to bring attention to in Australia. The Gillard Labor government came into power on the leader declaring there would be “no carbon tax in the government I lead” but promptly went into a convenient alliance with the greens and independents to form a government. C02 became the devil, the looming disaster, therefore a carbon tax HAD to be imposed to stop “Dirty Carbon Polluters” and save the planet. The green mantra meant that they must point out we were very large polluters when measured on a per head of capita basis in world emissions of C02. Our industry was to be crippled on the alter of demonizing C02 with emotional claims and unproven theories.
I tried to point out that the “Black carbon pollution” that Prime minister Gillard liked to claim when referring to C02, had in fact been removed along with other atmospheric pollutants for 30 years or more by way of very stringent EPA regulations and the installation of expensive emission scrubbers in all smokestacks, and intensive monitoring of other forms of pollution. Australian Industry and the Australian public had paid the cost, had paid the higher prices of the resulting domestic goods, and here we were being asked, to pay crippling additional costs because we had a small relative population when compared with other developed nations, when it was our leader trying to justify a huge carbon tax that would cripple our industry, reduce jobs as we paid guilt money to the green movement and what a lovely tax liked to ever rising C02, a tax meisters dream.
Of course they claimed the moral high ground as the reason for the carbon tax, why else? You have to wonder, as the green movement was insisting we must also close down our coal fired electricity generators, that had supplied us with some of the cheapest electricity power, we also could not build any dams to increase Hydro power output though we had several flood prone rivers suitable. My take was that we had cleaned up the atmosphere so much perhaps we had allowed more sunshine through?
The same government after imposing a carbon tax was encouraging the sale of our 500 year reserve of best quality coal, in an enhanced export program expected to cut that use time in half by exporting the coal to be burnt in countries like China and India, to fuel their power stations and feed their industry. These countries, unlike Australia haven’t been burdened with the need to scrub emissions of any kind from their smokestacks or clean up their own wasted environments.
Tasmania the Australian island state was once the “apple isle” of Australia, with large Forestry industries, and blessed with abundant Hydro power that supplied the cheapest electricity in Australia. Tasmania has been a hotbed of green activists, Taken over by green zealots who decimated the Forestry industries, reduced employment prospects. It now has the most expensive electricity in Australia, high unemployment, high welfare dependency and some of the highest food, fuel and commodity prices for domestic consumption.
America should send their economic experts to study how green activists can so cripple a state economy and reduce it to basket case status, before heading down that Green poverty path.

Mike Abbott
August 19, 2013 4:05 pm

Peter Miller says:
August 19, 2013 at 1:23 pm
Seems to make a lot of sense, so the Global Warming Industry will do their very best to ensure this theory is stillborn.
C’mon trolls, do your best..

No need for trolls. The best response from the Global Warming Industry comes from Martin Wild himself in the papers cited repeatedly by Anthony Watts. Wild is clearly in the AGW/GHG camp. He says global brightening is merely a temporary phenomena that “masks” the enhanced GHG effect. From the 2012 paper cited by Anthony:
“Thus, with the foreseeable inevitability
and undisputable necessity for clean air regulations
and aerosol reductions also in emerging nations,
potential dampening of global warming by a renewed
dimming could only be temporary, and greenhouse
gases will ultimately become the sole major anthropogenic
forcing factor of climate change.”
(Wild 2012)
He also launches a defense of the IPCC climate models, noting that they are accurate with respect to the southern hemisphere, where there has been far less “brightening” than the northern hemisphere:
This suggests that climate models simulate decadal warming
trends adequately when greenhouse gases act as the
sole major anthropogenic forcing as in the SH, but
may have difficulties when in addition strong decadal
aerosol variations come into play, as in the NH.

CNC
August 19, 2013 4:07 pm

The BBC Horizon (think PPS NOVA) did a whole one hour show on global dimming back in 2005. Of course back then to explain the cooling 1950-1980. Surprised more people did not comment on it here.
http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_prog_summary.shtml
Either way we sure should not be worrying about cutting CO2 as it is most likely a very small factor in warming which will not be a big deal at all. Any changes, most likely to be small, we will adapted to and not even notice.

Ed
August 19, 2013 4:11 pm

1) Does anyone believe that China’s air got cleaner between 1980 and 2000? I don’t.
2) If ∼20% increasing surface radiance over the last decade is ballpark correct globally and if increasing surface radiance is an important driver of temps, how is it that global temps have stagnated in the last decade?
3) Won’t these materials also absorb IR? IOW, isn’t it possible that increasing tropospheric concentrations might trap heat making temps higher?

Jimbo
August 19, 2013 4:11 pm

Let’s keep the Sun out of this eh.

meemoe_uk
August 19, 2013 4:19 pm

smoky vs clean air is a factor, but not the whole story.
Why the ” shocker ” superlative ? It’s old news.

RACookPE1978
Editor
August 19, 2013 4:20 pm

michael hammer says:
August 19, 2013 at 4:00 pm

The surface currently receives 243 watts/sqM on average. 20% increase would amount to an extra 48 watts/sqM. Just based on the stefan boltzman law that would equate to about 12C rise, significantly more if one takes into account cloud and ghg effects. If true it would imply negative feedback strong enough to reduces 12C to about 0.5C (assuming all the “adjustments” are justified). Even accepting that negative feedback is highly likely, that’s pretty strong negative feedback.

NO!
Well, not to be dramatic or anything, but NO!
Your point is close, but I think misses few things, most important that first-and-most-important “average” watts/sq mtr. Break that whole problem up by latitude 10 degree latitude bands and then try again. See where that logic leads to.
See, the “Clear Air Act”ONLY affected the USA from a narrow band of 40 north to 48 north. The south (say between the absolute furthest south point of Key West at 24.5 latitude up to 40 north latitude) had very little industry, and most of its “air pollution” if it could be counted at all was dust and dirt and tree pollen and emissions (Ozone is still high even today from the billions of pine trees …) LA was dirty, but that was one valley in one state. Where was the rest of this “pollution” that everybody claims?
Overseas? Europe was also in the high 40-50 latitude. Sahara (etc) are down low in the northern hemisphere. Nothing below the Equator to speak of that would be “turned off” to “stop” pollution.
Yet each of these latitude bands can be shown to absorb energy and reflect solar energy. Their emitted energy to space will depend on that emitted energy per latitude band three ways:
A. More is absorbed on the surface the closer you get to the Equator as a function of the cosine of latitude: At low equatorial latitudes, MUCH, MUCH more gets through the shallow air masses between the earth and the sun than reached the surface at higher latitudes.
B. .
C. ALL that solar energy that was absorbed at ANY latitude will be readily emitted back into space directly away from earth with a air mass of 1.0 by definition: The earth and sea will radiated “straight” into space, but will always be able to absorb less and less energy as you go away from the Equator to the pole.
D. In addition to the ever higher and higher attenuation of the solar energy through the atmosphere as it is absorbed trying to reach earth surface, less and less hits the earth’s surface per sq meter as you get closer to the poles because the earth’s surface slopes away from teh sun’s rays .
SO, for example, a 1.5 degree increase in the equatorial belts will matter far more than the

Jimbo
August 19, 2013 4:20 pm

Now with this new effort by O’Dowd et al., it seems quite likely that cleaner air is in fact allowing in more solar radiation to the surface, and thus increasing surface temperatures by that increase of insolation.

1850 to 1950 warming, blame man. 1910 to 1940 warming, blame man. Recent warming, blame Michael Mann and his Hockey Stick Trickery.

Txomin
August 19, 2013 4:21 pm

Quick, Mr. Obama, tweet it.

Tiredoc
August 19, 2013 4:21 pm

So, now we have 2 candidates for inadvertent anthropogenic effects? Fix the smog, warm the earth. Fix the ozone hole, warm the earth. Count me out of any theory attributing global variation to anthropogenic climate change of any stripe. To quote Rumsfeld, “we don’t know what we don’t know.” Enough already. We need to figure out the natural cycle first, and put the loons in the box with the cat.

Jean Parisot
August 19, 2013 4:25 pm

(I didn’t have a chance to read the paper yet, nor all the comments.)
Can this technique illustrate differences between Northern and Southern hemisphere measurement trends and or model outputs? Would that be a further proof of the technique?

Joe
August 19, 2013 4:29 pm

Zeke Hausfather says:
August 19, 2013 at 3:43 pm
[…]
Also, its worth pointing out that GCMs have long failed to match reality
—————————————————————————————————-
fixed that for you 😉

Jimbo
August 19, 2013 4:31 pm

The world has warmed by 0.8C since ~1850 / 1880. Most of the rise between that time and 1950 was mostly natural. What is the present problem? At most 0.4C? How much of that was caused by man?

Dr Burns
August 19, 2013 4:32 pm

As 1st world Clean Air Laws were becoming effective, 3rd world air pollution skyrocketed. Mace Head is hardly representative of the global atmosphere.

Chip
August 19, 2013 4:32 pm

I would disagree with one point. The air didn’t get cleaner because of laws, but because technology and wealth enabled us not to pollute.
China would love to clear the air over their cities. But this won’t happen until they reach a certain stage of development, and no law will change that.
I’m not being pedantic here. The fallacy that regulations improve our lives – rather than technological progress – is a belief driving many of the policies in the west today.
Regressive policies.

Hans H
August 19, 2013 4:35 pm

We know the effect of vulcanos..1000 coalplants in China would have the same effect wouldent it ? Sounds reasonable…

August 19, 2013 4:37 pm

Ie, we pay taxes for a situation that’s created by taxes …
… for what purpose …?
Disgusting …!

Richard M
August 19, 2013 4:38 pm

Nope, nothing more than a small factor.
Do any of you remember Bob Tisdale’s analysis? If it were aerosols we wouldn’t see the stepwise warming. It’s no more likely that aerosols created this warming than GHGs. For aerosols to have a cooling effect they need to get into the stratosphere. Man-made pollution just doesn’t get that high in any quantity. When lower in the Troposphere they have both a warming and cooling effect. Yes, they block sunlight but they also act like GHGs. The net result is they don’t have much effect at all.
Also, why did the recent warming stop right when the ENSO/PDO went into its cool mode? Why has the temperature trend matched the Pacific ENSO variability for almost 100 years? As Zeke noted, why don’t local patterns show more cooling where aerosols are the highest?
I’m afraid this is just another example of climate science failing to look at the bigger picture.

August 19, 2013 4:40 pm

@Schrodinger’s Cat :
” I realise that many people are not old enough to have experienced smog.”
Major problem …
@Latitude says:
” … but doesn’t fit this one at all
http://tamino.files.wordpress.com/2010/08/emission.jpg
Why not?
NH – lots of smog
SH – not so much. South America? South Africa? Australia/New Zealand? Pitcairn Island?
Since there is about 10% annual interchange across the ITCZ, and much of the muck has a short residence time in the atmosphere, there should be a significant difference.

Bill_W
August 19, 2013 4:46 pm

Occam’s razor might suggest simply natural variability combined with
a 60 year climate cycle. Hurricanes also have a 30 year cycle, don’t they?
Occam’s razor would say that you take the difference in slope (or the difference in
the magnitude of the change) between the warming from 1910 to 1940 and the warming
between ~1980 and 2005 and assign that to CO2 (possibly combined with other human effects
on climate such as soot and albedo changes).

August 19, 2013 4:49 pm

If this hypothesis is proven correct, this looks like the “law of unintended consequences ” in full effect.
Hmmm …. what’s a good environmentalist to do ????

Amber
August 19, 2013 4:50 pm

This is an example of why” The science is settled” claims of Big Al and other Mann made global warming promoters are such utter garbage. Ignoring the affects of the sun ,oceans and even improvements to air quality (with note worthy exceptions vary apparent) it is contrary to basic principles of science that a trace gas (CO2) drives temperature as these promoters say.
Yes humans have an affect and the long term trend has been warming fortunately. Can you imagine if the world had actually bought their BS and the cooling over the last 16 years was attributed to reduced CO2 ? Instead CO2 is up and temperature is flat. We need to use less and what we do use more wisely… no doubt..but this scam is over.

Philip Bradley
August 19, 2013 5:02 pm

Mike Jonas says:
August 19, 2013 at 1:42 pm
Count me out. This smells just like the claims that the ~1940-70 cooling was caused by (man-made, unmeasured) aerosols. This hypothesis only runs marginally OK from ~1940 onwards. It has no explanation for the ~1910-40 warming, or for the cooling before that. To me, it’s a non-starter.

The 1910 -1940 warming was caused by electricity (and to a lesser extent gas) replacing wood and coal fires for cooking.
In the USA and UK most new homes had electricity after 1910.

Philip Bradley
August 19, 2013 5:19 pm

Owen in GA says:
August 19, 2013 at 2:36 pm
This is fine to a point, but what would explain the decline between ~1878-~1910?

In the UK between 1830 and 1900 coal production increased from 30 to 230 million tons. Air pollution would have increased in line with production, as consumption of coal in power stations, which pollute far less, was still fairly limited in 1900.

Janice Moore
August 19, 2013 5:25 pm

Pamela Gray, Stephen Wilde, and Ed (and others with like arguments) win the day, here.
The latest attempt to blame humans for “climate disruption” has provided NO EVIDENCE that the alleged human emissions’ effect is not obliterated-to-the-point-of-insignificance by nature’s emissions.
Humans cannot warm,
cool,
change,
disrupt,
or even significantly affect
GLOBAL climate.
Until this is PROVEN, no economy-devastating policies should be formed based on such conjecture.

Jean Parisot
August 19, 2013 5:29 pm

Richard M says:
August 19, 2013 at 4:38 pm
Nope, nothing more than a small factor.
Do any of you remember Bob Tisdale’s analysis? If it were aerosols we wouldn’t see the stepwise warming. It’s no more likely that aerosols created this warming than GHGs. For aerosols to have a cooling effect they need to get into the stratosphere. Man-made pollution just doesn’t get that high in any quantity. When lower in the Troposphere they have both a warming and cooling effect. Yes, they block sunlight but they also act like GHGs. The net result is they don’t have much effect at all.

Did Bob Tisdale’s analysis separate the aerosols distributed primarily below the boundary layer from those above it, or did he analyze the troposphere as a whole?

Paulmur
August 19, 2013 5:35 pm

Hmmm….not convinced. It’s an interesting hypotheses but now you need to find a way to test it. Just making a series of statements that sound reasonable is not enough. The other side has abandoned the scientific method. We can’t do the same.

August 19, 2013 5:36 pm

Fascinating. This is a reverse Fallen Angels scenario, where government action against global warming makes it worse..
Fallen Angels was a Larry Niven – Jerry Pournelle – Michael Flynn SciFi novel written in 1991 that had the greens and religious Luddites take over the US government and pass a series of anti-technology laws to curb global warming. Unfortunately the clean up worked too well, ushering in the next ice age, complete with glaciers marching out of Canada. Fun book if you like Niven & Pournelle. Cheers –
http://en.wikipedia.org/wiki/Fallen_Angels_%28science_fiction_novel%29

Richard M
August 19, 2013 5:39 pm

Jean Parisot says:
August 19, 2013 at 5:29 pm
Did Bob Tisdale’s analysis separate the aerosols distributed primarily below the boundary layer from those above it, or did he analyze the troposphere as a whole?

Jean, sorry I wasn’t more clear. Tisdale does not discuss aerosols. Those were my own thoughts based on reading many articles at WUWT. Bob’s area of expertise is oceans where he shows strong evidence that a constant forcing (like GHGs) do not fit the actual pattern of warming. I was simply pointing out that the same arguments hold for aerosols.
Much of my aerosol thoughts were based on the fact that volcanic emissions seem to have very little effect unless we get a strong Stratosphere injection of aerosols. Willis also has a nice article about black carbon that I think is relevant.

Philip Bradley
August 19, 2013 5:44 pm

Ed says:
August 19, 2013 at 4:11 pm
1) Does anyone believe that China’s air got cleaner between 1980 and 2000? I don’t.

It’s a common misconception that atmospheric pollution has increased in China. As China industrialized and urbanized, people moved out of rural and urban homes where coal stoves and fires were used for cooking and heating to apartment blocks where electricity was used. This shifted coal burning from inefficient and polluting stoves to efficient power stations. Resulting in much less black and organic carbon pollution, although as coal consumption greatly increased, SO2 pollution greatly increased.
This why India, where there has been much less urbanization, outside the monsoon season, has steadily cooled through the 20th century, while China has warmed over the last 30 years.
This also explains why northern China has warmed 2 to 3 times faster than southern China, where the need for domestic heating is much less.

RoHa
August 19, 2013 5:44 pm

So it’s all Anthony Eden’s fault.
http://en.wikipedia.org/wiki/Clean_Air_Act_1956

Philip Bradley
August 19, 2013 5:53 pm

Paulmur says:
August 19, 2013 at 5:35 pm
Hmmm….not convinced. It’s an interesting hypotheses but now you need to find a way to test it.

This theory can be tested in any city in the world over the weekly aerosol cycle (The Weekend Effect). I have remarked before that it is scandalous that climate science, where real world experiments are notoriously difficult, has completely ignored the opportunity to measure the effect of various kinds of aerosol pollution on temperatures over conveniently short timescales.
There has not been a single published paper in the last 20 years measuring the effect of urban aerosols on temperatures Excepting a few that show the effect of aerosols only the climatically meaningless DTR.

johndo
August 19, 2013 5:55 pm

Michael Hammer is starting to ask the right question.
In spite of RACookPE1978’s comment it does not matter whether you use a world surface average 140 w/sq m average or direct insolation fron the sun 1361 w/sq m, if 20% more is received the temperature must go up a little less than 4% to radiate out the extra energy as heat (IR).
Using a surface average of 13 degrees C (=284 degrees K) and yes I know lots will want to split hairs about that, but an average temperature rise of over 10 degrees C is required.
The measured figures given by Sunshinehours1 for Netherlands was around 6 w/sq m (maybe 3.5%), and surprisingly match (or are less than) the increase given by Palle et al in 2006 (and earlier).
BY E. PALLÉ, P. R. GOODE, P. MONTAÑÉS-RODRIGUEZ, AND S. E. KOONIN in EOS
That was from cloud cover changes !
Surely we need to understand the cloud (water vapour) effects better before we leap to other things.

Erik Nobel
August 19, 2013 5:56 pm

@ Schrodinger’s Cat
if people want to get an idea of what smog was like in the 60s & 70s in Los Angeles area .. take a look at pictures of Bejing these days ..

David Riser
August 19, 2013 6:03 pm

I would say give them a chance, at least they are conducting science. I am not sure that they have it right but I would guess its a small piece of the puzzle. At the end of the day .8C over the long haul with mostly stepwise changes is insignificant when you consider the probable error of that somewhat misbegotten number is most likely greater than the overall change (around 1.1C in potential measurement error alone). Mann needs to get off the stick and start doing some actual science……

ROM
August 19, 2013 6:27 pm

From the paper it appears that solar energy would be absorbed by the ultra fine Particles in the stratosphere leading to stratospheric warming.
Otherwise the without a good level of particle reflectivity, if solar radiation is not getting through the layers of particulates to the ground, then a high amount of solar radiation must be absorbed by the stratospheric particulates leading to a long term stratospheric warming.
As the stratospheric particulate pollution slowly drifted down during the couple of decades from the late 1960’s on and the stratospheric particulates were not replaced after the 1970’s due to the cleaning up of the industrial pollution, the stratospheric temperatures, with less and less solar energy absorbing particulates, would start to cool.
Which seems to have been the case as it appears that stratospheric temperatures have very slowly fallen over the last couple of decades.
Following the atmospheric nuclear tests of the 1950’s and 60’s it was found that the radioactive stratospheric residues from these tests took up to 15 months to cross the ITCZ from the northern to southern hemisphere. From this it would also appear that the equatorial weather systems are a considerable barrier to northern hemisphere pollution crossing into the southern hemisphere in any significant amounts.
The Southern Hemisphere’s land mass including nearly all of South America, one third of the African continent, Australia and New Zealand, most of Indonesia and the Antarctica covers about one third of the global land mass area.
Without Antarctica, the southern hemisphere’s land areas are reduced to about 24 % of the global land mass.
Nowhere throughout these southern hemisphere land areas were there any large concentrations of polluting industry prior to the 1950’s when Australia and to some extent Argentina began to industrialise.
Brazil and Indonesia only began to industrialise in the 1980’s and southern Africa still hasn’t any large concentrations of industry except in some pockets in South Africa.
So compared to the huge industrial regions and high population densities of the northern hemisphere and their consequent capabilities to produce globe circling pollution and hypothesised cooling particulates, in the southern hemisphere such polluting capabilities from industry and populations were globally only of a very small consequence until late in the 1980’s..
From the barrier effects of the equatorial weather systems to the ingress of any northern hemisphere pollution into the SH and the lack of major population densities and the small industrial bases of the southern hemisphere, we would expect to see some quite large differences between the southern hemisphere and northern hemisphere upper atmosphere pollution levels and consequently the long term temperature records ie cooling in Northern Hemisphere in the 1960’s and 70’s and then warming from then on compared to a quite steady but very slow shift of temperature trends in the Southern Hemisphere over the same period.
If the hypothesis as provided in the paper is near correct, any global temperature trends should show very significant differences between the northern and southern hemispheres temperature changes and trends over a 5 decades long time frame from the 1950’s to the 1990’s..
All due to effects of the probable differences in the amounts of stratospheric particle pollutants between the NH and the SH.
The raw data temperature from both Australia and NZ both indicate an almost steady base temperature right through those 5 decades while the northern hemisphere was first cooling in the 1950’s, 60’s and 70’s and then supposedly warming from about 1977 through to 1997,
A short two decade long [ NH only ? ] warming period upon which the entire claimed proof of a catastrophic global warming is solely and completely based.
The Australian and NZ historical and raw temperature data has been severely corrupted and shifted to an upward trend in both countries by the more rabid warmists in both in Australia’s Bureau of Meteorology and by NZ’s even more notorious rabidly warmist cell at NIWA.
This site below has done a large amount of Australian temperature analysis and has a lot of information on the very substantial adjustments made by elements in the BOM to Australia’s temperature data.
kenskingdom
http://kenskingdom.wordpress.com/
And for NZ, WUWT;
New Zealand’s NIWA temperature train wreck;
http://wattsupwiththat.com/2010/10/09/new-zealands-niwa-temperature-train-wreck/
So summing up, if the claims of the amount of stratospheric particulates being the probable cause of first global cooling and now as those high levels of particulates drift out and down out of the stratosphere, allowing clearer skies for more solar radiation to penetrate to the surface and a consequent warming,. there should also be quite large and easily detectable decadal variations and trends between the changes in temperature in the northern hemisphere and the temperatures of the southern hemisphere..
And just for interest, Because of our location and the sparseness of land masses in the SH plus the only locations that have trustworthy weather data going back over a century, Australian and New Zealand’s historical temperature records as utilised by climate researchers cover close to 25% of the global surface.
So any adjustments, spurious or otherwise to our records have a very large impact on the historical global climate data and the flow on effects from the use of that data.

Latitude
August 19, 2013 6:29 pm
Dan Cummings
August 19, 2013 6:30 pm

So let’s say there’s something to this. Combined with banning of certain CFCs starting in 1978 which University of Waterloo’s Qing-Bin Lu said coincided with temperature rise until 2002. Then take into account the population growth and huge use of unscrubbed coal plants and soot from cooking stoves in India and China which could fully account for anomalies in China and India data (see figures above) that stopped overall heat gains post-2002, and we may have a more wholistic sense of what’s happening. Add in the polarity shifting of our sloshing, spinning liquid iron core and that potential set of effects along with the sun’s changes, and it sure looks like wasting time and energy on minuscule CO2 percentages is 100% pure foolishness.
It would be more effective to array large mirrors (or even solar arrays, perhaps) on deserts to reflect heat back to space while planting more trees and using dark roofs in colder places where we want more heat, to enhance life and growing seasons in northern US and Canada. (I’m not advocating the mirrors, just sayin’ .)

DesertYote
August 19, 2013 6:36 pm

Lance Wallace says:
August 19, 2013 at 1:41 pm
###
If were you are talking about is Santa Rosa California, I lived there for 10 years. What you are seeing is not smog, but a natural fog condition. You are living right on the edge of a fog forest. Many plants of fog forests are fog-eaters such as the Red Woods (and introduced gum trees). These plants emit aromatics that precipitate the fog and a leaf structure that captures the droplets.
If you want to see real haze, then wait until there are some serious forest fires burning in the area!

Crispin in Waterloo
August 19, 2013 6:36 pm

I am glad some readers are measuring actual particles instead of just talking about them.
There are neighbourhoods in Ulaanbaatar (from where I sometimes write) with an annual average of 600 micrograms/cubic metre (PM2.5). Beijing is clean in comparison. The temperature in the city has been rising rapidly over the past 60 years but is now tumbling. I do not see any relationship between the PM and the temperature. It is pretty clear on extremely cold days and the worst pollution is in November when it is not all that cold.
More than half the PM2.5 in Beijing comes from the farmlands around the city. That brings up the question of land use changes, not aerosols.
My conclusion so far is that local effects are of little consequence. The brightening is real and some of us may remember the global dimming scare that was a kite flown for our attention some years back. It did not sell as well as CO2.
Water droplets are very effective at scattering light. Agricultural methods have changed – is that not a large factor over that time period. Black carbon is a very effective air-warmer and sunscreen at the same time but it is almost always co-emitted with organic carbon. Maybe there is an interplay between the ratios of BC to OC that swamps all other considerations. Prof Liu here in Waterloo concluded it was Antarctic ozone that dominated temperature. Can ozone dim or brighten as well? At which frequencies? High energy UV for sure. Was the brightening gained and lost full spectrum or visible? Enquiring minds want to know.

Jean Parisot
August 19, 2013 7:13 pm

Richard M says:
August 19, 2013 at 4:38 pm
et al On aerosols
I only ask because Ive measured a lot of aerosols in a LOWTRAN scenario – but very few in a HITRAN scenario that weren’t related to an event that injected them into the upper atmosphere.

Philip Bradley
August 19, 2013 7:28 pm

Urban aerosols cause ozone production locally and for a large distance downwind.
Atmospheric production of ozone and visibility reducing aerosols continues long after their primary precursors have been dilute to low concentrations.
http://capitawiki.wustl.edu/images/0/0a/76j10.pdf
Clearly, some complex and poorly understood chemistry going on.
I agree that we have little idea of the effect of various atmospheric substances,loosely called aerosols, have on temperatures, individually or in combination. The forcings ascribed to aerosols by climate science, are just the fudge factors used in the climate models.

Theo Goodwin
August 19, 2013 7:55 pm

Mike Haseler says:
August 19, 2013 at 2:32 pm
At this time, we cannot say exactly how much “atmospheric brightening” contributed to warming or how much China’s recent emissions contribute to cooling. What we can do is point out the remarkably poor reasoning of Alarmists. In doing so, I am just emphasizing what Mike and others have written above.
Back before Trenberth convinced most Alarmists that the “missing heat” is hiding in the deep oceans, Hansen and some other Alarmists were blaming the “pause” on aerosols from China, India, and such places. Apparently, it never occurred to Hansen and friends that if aerosols could explain the “pause” then the lack of them could explain the rise in temperature. What really galls me is that Hansen and friends really did not do empirical research on aerosols. If they had they would have seen that the aerosol sword cuts both ways. (Conspiracy theorists will draw another conclusion but that does not interest me.)
We good hearted lovers of science have been begging the “Alarmists in power,” such as Hansen, to engage in real world research on natural variability. With regard to aerosols, we have a case of them refusing to engage in real world research on manmade (unnatural) contributors to temperature change. Hansen and friends were interested only in using increasing aerosols from China as an excuse for the “pause.” By comparison to the work of recognized scientists over the last 300 years, Alarmists simply are not interested in empirical research.

August 19, 2013 8:06 pm

Lawrence Todd says:
August 19, 2013 at 1:02 pm
If i get this right, industrial pollution masked the natural warming from the Little Ice Age and the clean air initiatives caused the earth temperatures to rebound to normal levels.
REPLY: Bingo. – Anthony
————————————————————————–
That’s not the impression I get from looking at CET from 1730 to 1930
http://snag.gy/2q2kT.jpg
Don’t you think a rational reason for that amount of increase in sunshine is simply a more positive NAO/AO and a more northerly Jet? That’s the way it usually works here.

old engineer
August 19, 2013 8:15 pm

Joe says:
August 19, 2013 at 4:29 pm
Zeke Hausfather says:
August 19, 2013 at 3:43 pm
[…]
Also, its worth pointing out that GCMs have long failed to match reality
—————————————————————————————————-
fixed that for you 😉
=========================================================================
Sorry Joe, but you didn’t fix it. Zeke was right, the GCM’s do include the effects of atmospheric aerosols. Going back to Hansen, et.al. 1988. In Appendix B of Hansen’s paper, there are 4 things listed as having negative radiative forcings: stratospheric and tropospheric sulfuric acid aerosols, tropospheric desert aerosols, and land albedo.
However, you are right also. They have failed to match reality, but more from overestimating green house gas effects than failing to include aerosols.

george e. smith
August 19, 2013 8:30 pm

“”””””……Chip says:
August 19, 2013 at 4:32 pm
I would disagree with one point. The air didn’t get cleaner because of laws, but because technology and wealth enabled us not to pollute…….””””””
Well I don’t know about where you live; but in California, our air has gotten cleaner, in spite of the clean air laws.
First they gave us MTBE and ETBE in our gasoline to “oxygenate it”.
That meant that less “oxygenation” could take place in your automobile’s under the hood “oxygenator” , aka “Engine”.
So we got about 15% less mileage, for the same tank full of “reduced fuel.”
That meant that we had to buy and burn more fuel, as well as getting rid of the oil company’s garbage for them. it had the added benefit, in that the fuel tanks leaked, and polluted about half the ground water wells in California.
So we got the to remove the MTBE; but they replaced it with another “reduced fuel” oxygenator; Ethanol; which then placed greater strain on clean water availability, growing and converting all that maize.
So we still get our quota of reduced gas mileage, causing us to burn more fuel along with the faux fuel. The ethanol fuel, has one advantage, if you leave the tank open a bit, if not driving, you can evaporate some of that junque, and get a better blend og gasoline, with less “oxygenator” in it.
Well you can’t get around having to buy the oxygenator, anyway.
Can’t blame the oil Companies though. They say they can meet all the fuel standards, without any ersatz fuel.
Despite that, the car companies have made their cars much more efficient, despite being hamstrung by the unfuel gasoline.

highflight56433
August 19, 2013 8:43 pm

…peer review? Like having 12 bank robbers as jurors to pass judgment over a bank robbery case.

August 19, 2013 8:44 pm

At the possible end of the latest extreme interglacial, it might not matter one whit.
Go ahead. Knock your H. sapiens sapiens selves out……….
“Seas rose to 30 feet above modern level during a time of similar global warming — study’
Published: Wednesday, August 14, 2013
Climatewire
“Scientists exploring elevated fossil beaches and coral reefs on the remote western coast of Australia have found what they say is compelling evidence that near the end of the Eemian interglacial period, sea level jumped to close to 30 feet above the modern level.
“During the Eemian, a warm period in Earth’s history that preceded the most recent ice age and a time when planetary temperature was similar to levels projected in the coming decades, sea level stabilized at about 10 to 12 feet above the modern level for several thousand years. However, the new research indicates the level then spiked an additional 17 feet.
“In a paper published in late July in Nature Geoscience, Michael O’Leary of Australia’s Curtin University and five colleagues build on the work of scientist John Mercer. Thirty-five years ago, Mercer issued a warning about the consequences of human-related carbon emissions.
” His paper “West Antarctic Ice Sheet and CO2 Greenhouse Effect: A Threat of Disaster” points out the unusual topography of the ice sheet atop the western part of Antarctica. Much of the ice sheet is below sea level, in a bowl-like shape. According to Mercer, a climatic warming could lead the entire ice sheet to degrade rapidly on a geologic time scale, creating a possible 16-foot rise in sea level.
“In a recent interview, O’Leary said he was confident that the 17-foot jump in sea level he found evidence for occurred in less than a thousand years. He didn’t know how much less.
“The sediment record suggests a jump of this sort, according to Paul Hearty, a team member and North Carolina field geologist. Hearty has argued the possibility for decades, but measurement and modeling techniques have only recently reached the level of precision needed to confirm it.
“The findings must withstand further scrutiny. Andrea Dutton, a sea-level scientist at the University of Florida not involved in the research, said the paper failed to disclose enough information about the field sites to allow her to judge the overall conclusion.
“The only possible explanation for such a big, rapid rise in sea level is the catastrophic collapse of a polar ice sheet, on either Greenland or Antarctica (Justin Gillis, New York Times, Aug. 12). — CJ”
OK, I got that. It may have already happened anyway, on much lower ambient CO2 during the end of the last interglacial.
If it has already happened, wildly in excess of the half-precession old Holocene (and at much lower end extreme interglacial CO2 concentrations), what is it exactly that you would propose in terms of atmospheric CO2 concentration, to augment, delay or prevent our induction into the next glacial?

Theo Goodwin
August 19, 2013 8:58 pm

old engineer says:
August 19, 2013 at 8:15 pm
“Sorry Joe, but you didn’t fix it. Zeke was right, the GCM’s do include the effects of atmospheric aerosols.”
But these are just Hansen’s best guesses on a given day. There is no empirical research behind what they have on aerosols in the GCMs. Anyway, if you had valuable empirical research on aerosols you would be trumpeting it from the highest mountain rather than using it in a GCM.

August 19, 2013 9:16 pm

The smoke from all those forest fires near Moscow in Summer 2010 made it hotter there. Summer 1783 in England it was roasting during the 3 months that it was engulfed in low level volcanic dust and fumes. Is burning coal why England’s Summers were hotter in the 1700’s than the 1900’s?

August 19, 2013 9:19 pm

I’m skeptical. This is a reverse version of the same hubris.

August 19, 2013 10:02 pm

Mike Abbott says: “Wild is clearly in the AGW/GHG camp.”
Wild pays lip service to AGW/CO2 in order to prevent his funding from being cut off. But those statements aren’t backed up by anything in his papers.
The science in his papers contradict AGW/CO2 if you had read them.

Philip Bradley
August 19, 2013 10:35 pm

Nowhere throughout these southern hemisphere land areas were there any large concentrations of polluting industry prior to the 1950′s when Australia and to some extent Argentina began to industrialise.
It’s a Left Liberal myth that air pollution comes and came from industry. The largest source of atmospheric pollution up until the clean air acts was domestic burning of coal and wood. Motor vehicles pre-catalytic converters, and agricultural burning would have been the next 2 largest sources. Agricultural burning still occurs in Australia, and I believe it is still widespread in South America.

August 19, 2013 10:48 pm

“UK Tmax versus Sunshine are well correlated. Cleaner Air. More Sunshine.”
http://sunshinehours.wordpress.com/2012/12/05/uk-tmax-versus-sunshine-are-well-correlated-cleaner-air-more-sunshine/

August 19, 2013 11:00 pm

Why so much love for anthropogenic climate change? Man is puny. Climate changes all by itself (and sun).

tonybclimatereason
Editor
August 19, 2013 11:14 pm

Can I have my grant and Nobel prize please? I mentioned this in an article here two years ago. Because of pollution historic temperatures were depressed and because of the clean up we then got more sun.
http://wattsupwiththat.com/2011/05/23/little-ice-age-thermometers-%E2%80%93-history-and-reliability-2/
“Many of the cities with the longest temperature records- generally in Europe and North America- were industrialising rapidly as the thermometer came into widespread use in the 1700′s. Smog caused by the burning of coal, wood, and later gas, became increasingly widespread. Sunshine levels in the UK are said to be 40% higher now than during the worst years in London that culminated in the 1952 killer smog, which caused the various clean air acts to be enacted fully. Pollutants are said to create a cooling effect and it is easy to understand that foggy urban areas were likely to be substantially cooler than if the sun was shining. Inversions caused by these layers of air would have also helped to create temperatures that were vastly different-mostly lower-than they might otherwise have been. What effect this had on the overall temperature record over the centuries, in the many cities that smog affected to a greater or lesser degree, is impossible to calculate, but it must have been significant.
Perversely, smog became a tourist attraction and many artists flocked to great cities such as London to observe and paint the effects it caused.
Waterloo Bridge London in 1900 by Monet showing chimneys and smog. http://www.artnet.com/Magazine/features/nkarlins/karlins7-7-04.asp
An account of the historical development of smog is mentioned here;
http://en.wikipedia.org/wiki/Pollution
—– ——-
tonyb

MangoChutney
August 19, 2013 11:33 pm

Sounds plausible, but does the paper explain the stop in rising temps?

phlogiston
August 19, 2013 11:51 pm

With the oceans, containing 99% of climate heat, any attempt to explain climate which ignores dynamics of ocean circulation is ultimately doomed. This is the “deus ex machina” atmosphere-only thinking which characterizes the AGW narrative, the belief that only human atmospheric input and nothing else can change climate, with the oceans as a passive puddle following solar/atmospheric forcing in real time. What happened to the PDO and the AMO? What about the AMOC, the bipolar seesaw and inter-hemispheric heat piracy? If we go down the road ending in believing that every fart affects the climate but the oceans are irrelevant, we will have totally lost connection with reality.

Chris Schoneveld
August 20, 2013 12:13 am

So CO2 would have warmed the earth during the 1945 and 1975 period if it wasn’t for the air pollution. So this result confirms the arguments the warmists always used to explain why there was a lack of correlation between CO2 and T for that period. So nothing new.

Andre
August 20, 2013 12:20 am

” leading to a staggering increase in surface solar radiation of the order of ∼20% over the last decade.”
Yes but the last decade has not been warming. Would it have cooled a lot instead? without the increased radiation?

Patrick
August 20, 2013 12:25 am

“Mike Jonas says:
August 19, 2013 at 1:42 pm”
As well as power stations being built and grids being rolled out in the periods you mention, there was WW1, WW2, many ground/air nuclear bomb tests, several other wars which require significant industrial activity to support and would have kicked up plenty off dust.

mikef2
August 20, 2013 2:46 am

After years following this, I’ve come to the conclusion that there is no global warming, never was (slight variations with ocean changes excepted). Its a statistical artefact caused by cooling the past in the surface temp history, a bit of unaccounted uhi, stuff like that. The reason for the ‘pause’ is that they have run out of fiddling room, pure & simple. The more I watch the sat temps bumbling around a 0.3C variance, the more I’m convinced.
So this paper is just another attempt to explain the ‘pause’ without wanting to see the elephant in the room.

August 20, 2013 3:20 am

Do Inda and China know all those global climate refugees are headed their way?

August 20, 2013 3:21 am

[ note to self: proofread before post! ]. That should be “India” above instead of “Inda”.

Mike
August 20, 2013 3:34 am

One thing that puzzles me is that there is a large amount on material on the internet describing ever increasing levels of pollution, for example :-
http://www.ucsf.edu/news/2013/02/13487/maternal-exposure-air-pollution-linked-low-birth-weights-worldwide
I’m not actually sure where the evidence is to show that the developing world and China have many pollution controls, I thought as the levels of pollution were controlled and reduced in the West, then the economic development in China and the Indian sub-continent etc, more than made up for it, so that worldwide they are now at levels of the late 1960’s.
If this is the case then the build up of various types of pollution may very well have moved around the world, but have not fluctuated much. Not sure where it leaves the AGW theorists and their excuse for the lack of warming since 1998. It is interesting to note that where ever there is an unexplained lack of warming then the particulate / pollution excuse is rolled out, only to be rolled back when any warming starts again, shazam ! just like something out of a Harry Potter film.

Chris Wright
August 20, 2013 3:58 am

It would be a wonderful irony if it turned out that global warming was caused by environmental laws.
Probably most of the clean air acts were enacted in the developed world, so, if this idea is correct, you might expect to see more warming over the developed world e.g. Europe and the US. If I remember correctly, more global waming occurred in the northern hemisphere and it does appear to be concentrated over the developed world. It would be interesting to see if there is a significant correlation between the amount of warming and global regions which are more and less developed.
Chris

August 20, 2013 4:06 am

Shocker: Sea Level Could Rise 3 Feet by 2100, Climate Panel Finds
A new report from the Intergovernmental Panel on Climate Change states that the authors are now 95 percent to 100 percent confident that human activity is the primary influence on planetary warming.
http://www.nytimes.com
Link:
http://www.nytimes.com/2013/08/20/science/earth/extremely-likely-that-human-activity-is-driving-climate-change-panel-finds.html?pagewanted=all&_r=0&hp
By JUSTIN GILLIS
Published: August 19, 2013
The scientists, whose findings are reported in a draft summary of the next big United Nations climate report, largely dismiss a recent slowdown in the pace of warming, which is often cited by climate change doubters, attributing it most likely to short-term factors.
The report emphasizes that the basic facts about future climate change are more established than ever, justifying the rise in global concern. It also reiterates that the consequences of escalating emissions are likely to be profound.
“It is extremely likely that human influence on climate caused more than half of the observed increase in global average surface temperature from 1951 to 2010,” the draft report says. “There is high confidence that this has warmed the ocean, melted snow and ice, raised global mean sea level and changed some climate extremes in the second half of the 20th century.”
The draft comes from the Intergovernmental Panel on Climate Change, a body of several hundred scientists that won the Nobel Peace Prize in 2007, along with Al Gore. Its summaries, published every five or six years, are considered the definitive assessment of the risks of climate change, and they influence the actions of governments around the world. Hundreds of billions of dollars are being spent on efforts to reduce greenhouse emissions, for instance, largely on the basis of the group’s findings.
The coming report will be the fifth major assessment from the group, created in 1988. Each report has found greater certainty that the planet is warming and greater likelihood that humans are the primary cause.
The 2007 report found “unequivocal” evidence of warming, but hedged a little on responsibility, saying the chances were at least 90 percent that human activities were the cause. The language in the new draft is stronger, saying the odds are at least 95 percent that humans are the principal cause.
More at Link:
http://www.nytimes.com/2013/08/20/science/earth/extremely-likely-that-human-activity-is-driving-climate-change-panel-finds.html?pagewanted=all&_r=0&hp
James B
Chicago

August 20, 2013 5:08 am

@tonybclimatereason
April to August 1952 on CET are very much on the warm side, do you have figures for London during that smog?

Kip Kotzan
August 20, 2013 6:00 am

Extra irony here when you think about how the CAGW folks have sold the scare to the general public. Most non-scientists are screaming about “carbon pollution” causing the world to heat up. They think “pollution” is causing warming. They get furious with you if you argue against the climate alarmist agenda because they are certain you are against stopping “pollution.” So you must either work for the oil industry, be an idiot or hate the planet.
Perhaps a great moment for us to push back if we could get folks to understand that what they think of as pollution, sooty emissions, cools the planet.

tonyb
Editor
August 20, 2013 6:33 am

Ulric
Here is London weather. seems to be on the cool side in 1952. The smog was very ,localised and Greenwich due to its height/location may have missed it.
http://www.london-weather.eu/category.46.html
Annoyingly, the official figures for Greenwich are missing for a couple of years including 1952
http://climatereason.com/LittleIceAgeThermometers/Europe.html
tonyb

climatereason
Editor
August 20, 2013 6:43 am

Ulric
Interesting letter here from the weather keeper at Kew close to Greenwich in 1952
http://onlinelibrary.wiley.com/doi/10.1256/wea.09.03/pdf
tonyb

richardscourtney
August 20, 2013 7:31 am

James B:
You have copied your daft post at August 20, 2013 at 4:06 am on another thread.
I refuted it there and this link goes to my refutation.
http://wattsupwiththat.com/2013/08/19/ipcc-caught-with-an-old-uncorrected-error-in-new-ar5-report/#comment-1395290
Richard

Patrick
August 20, 2013 7:32 am

“tonyb says:
August 20, 2013 at 6:33 am”
The smog in London was a photographers delight back then. Soft, diffused light.

David ashton
August 20, 2013 7:49 am

Also explains why Northern and Southern hemispheres behaved differently.

Pamela Gray
August 20, 2013 8:14 am

Re: New York Times article By JUSTIN GILLIS
Published: August 19, 2013
Notice the slight of hand change from “increasing” climate extremes to “changing” climate extremes. So now any climate extreme change, IE up, down, more, less, here, there, is likely at least greater than 50% prompted to occur because of human factors.
So now we have the bottom line. Humans cause bad weather. We have made a complete turn around back to caveman days when lightening was a sign from the gods that we have done something wrong. Quick! Find a virgin!

Box of Rocks
August 20, 2013 8:20 am

What a crack of horse sh*t.
First off I suspect that the is ** NO ** direct linear relationship between electromagnetic radiation hitting a small particle of “something” or pollution and the amount of radiation is back scattered.
Anybody care to share an “energy balance” equation of an airborne particle being struck by radiation – from the sun?

TRM
August 20, 2013 8:43 am

We go from -24 to +10 and now back to -3.
Is the recent 15 year flatline due to China and India? If so please stop it as I like a warmer, greener world. I don’t mind them putting CO2 into the air as long as they stop polluting while doing it 🙂

Gail Combs
August 20, 2013 9:14 am

What about the 1930’s Dust Bowl? (1932-36) When dust from the Midwest was blown all the way to Washington DC?
1. We know the 1930’s were hotter than now.
2. In 1930 13% had electricity in rural America. by 1940 33% had electricity. (Farmers made up 21% of labor force)
3. This graph shows the use of coal (by percentage) peaking in the 1920/30’s

When inspecting old buildings, there’s often some evidence that it was heated with coal at one time. Even really old buildings, originally heated with wood, may have had a central coal heating retrofit. Old wood burning fireplaces may have been blocked off and coal stoves had been piped into the old chimney flues. Some buildings still have their original coal fired boiler or furnace, but it has been converted to fuel oil or gas. In many 19th century homes, an old abandoned chimney used to serve a coal cooking range in the original kitchen. Many basements still have their coal bin….
The second half of the 19th century and into the first quarter of the 20th saw coal as the most abundant fuel most widely used–not only for heating but for powering most industrial processes. The First World War created major shortages of coal and its use peaked right before 1920. By the mid 1930s, fuel oil burners finally became safe and reliable. By the beginning of the building boom right after the Second World War, coal for heating was seen as old technology.
link

beng
August 20, 2013 9:31 am

The avg ignorant warmer would just use this to justify EPA expansionism. They think CO2 is just another pollutant.

Gail Combs
August 20, 2013 9:35 am

Pamela Gray says: @ August 20, 2013 at 8:14 am
Re: New York Times article By JUSTIN GILLIS
Published: August 19, 2013
Notice the slight of hand change from “increasing” climate extremes to “changing” climate extremes….
So now we have the bottom line. Humans cause bad weather. We have made a complete turn around back to caveman days when lightening was a sign from the gods that we have done something wrong. Quick! Find a virgin!
>>>>>>>>>>>>>>>>>>
Or Burn that Witch!
Unfortunately we are the ‘Witches’

…it has not been unusual for prominent activists to publicly call for dire punishments of skeptics. In 2008, NASA’s James Hansen, a leading global warming alarmist, used a speech before Congress to argue that oil company executives should be “put on trial for high crimes against humanity and nature”/ for fostering doubt about global warming. Robert Kennedy, Jr. called coal companies “criminal enterprises” and said that one coal CEO “should be in jail … for all eternity” both for selling a high-carbon product and being publicly skeptical of global warming. Anonymous web posts calling for death to climate skeptics are practically routine, with one blog post (later deleted) at leftish Talking Points Memo asking “at what point do we jail or execute global warming den1ers?”
FORBES: Why Blowing Up Kids Seemed Like a Good Idea

If you can not blame humans you can not scare them into changing their behavior and demanding homage and indulgences (taxes) be paid.
This sounds like more of the same, the weather is bad humans are to blame, crap. Is there some truth in it? Probably but as with the CO2 scare the truth is a tiny kernel wrapped in propaganda and distortions.
The CO2 propaganda is getting quite a bit ragged around the edges and this helps prop it back up. The Climate modes were off because we left out Human Caused aerosols. Heck you can even blame the Dust Bowl on humans. Remember the farm dust which the EPA now wants to regulate.

jorgekafkazar
August 20, 2013 10:08 am

MattN says: “I remember this scenario being discussed years ago here at WUWT. Not sure how much I buy it. 20% is a whole lot.”
I agree with MattN and Michael Hart and Geo Smith and many others, above. The 20% figure doesn’t pass the sniff test. Way too much compared to my sight test and other personal observations. I, too, as per Richard M, was thinking of Bob Tisdale’s work in this context. I just can’t subscribe to the theory.
But the science isn’t settled yet, is it?

August 20, 2013 10:10 am

One of the problems with trying to PROVE a correlation between cleaner/dirtier air and more sunshine/less sunshine is the lack of data. I’ll use Canada as an example. There used to be over 250 stations collecting bright sunshine data in 1970. Now there are 7.
http://sunshinehours.wordpress.com/2012/12/08/nov-2012-canada-only-7-stations-collecting-sunshine-data/

August 20, 2013 10:13 am

“The 20% figure doesn’t pass the sniff test. ”
Spain. 6.5W/m2 per decade increase in summer sunshine from 1985-2010 .
A doubling of CO2 is supposedly only 3.7W/m2.
http://sunshinehours.wordpress.com/2012/11/30/sunshine-up-in-spain-from-1985-to-2010-by-3-9wm2/

August 20, 2013 10:19 am

UK
In the mid 2000s, the anomaly was 9.48 hours more sunshine per month.
Thats over 100 extra hours per year in a country that gets around 1400 hours. 7% averaged over the whole year.
http://sunshinehours.wordpress.com/2012/07/02/uk-met-bright-sunshine-5-year-averages-plotted-using-all-monthly-anomalies/

John F. Hultquist
August 20, 2013 10:56 am

tonybclimatereason says:
August 19, 2013 at 11:14 pm

Thanks for the link to the “Beautiful Smog” article by Karlins.
Such things are fascinating in their connections of history, art, geography, and atmospheric aspects. There was a well done one for “The Scream” that I cannot now find. Here is another but more condensed version:
http://voices.yahoo.com/the-volcanic-explosion-krakatoa-influenced-edvard-1406579.html?cat=37

August 20, 2013 10:58 am

tonyb says:
“Here is London weather. seems to be on the cool side in 1952. The smog was very ,localised and Greenwich due to its height/location may have missed it.
http://www.london-weather.eu/category.46.html
Well it was a warm dry Summer in London like much of the country, but what I should have done was research the smog, which appears to be a freezing fog from the 5-9th December:
http://en.wikipedia.org/wiki/Great_Smog
http://www.tutiempo.net/en/Climate/Londres_Heathrow_Airport/12-1952/37720.htm

Mike Abbott
August 20, 2013 11:02 am

sunshinehours1 says:
August 19, 2013 at 10:02 pm
Mike Abbott says: “Wild is clearly in the AGW/GHG camp.”
Wild pays lip service to AGW/CO2 in order to prevent his funding from being cut off. But those statements aren’t backed up by anything in his papers.
The science in his papers contradict AGW/CO2 if you had read them.

It’s more than lip service. Dr. Wild is Associate Editor of the Journal of Geophysical Research, a publication of the American Geophysical Union. He is also a Lead Author on the IPCC’s AR5. In many interviews and publications, he expresses his belief in the enhanced GHG effect. (See http://www.iac.ethz.ch/people/wild.) I rest my case.
I think Dr. Wild would view his findings as complementing GHG theory and I see examples of that in his papers. The best example is in his detailed discussion of NH vs. SH climate model accuracy. In any case, there definitely is one glaring discrepancy: If the recent “pause” in surface temperatures can be explained by Wild’s global brightening theory, what does that say about Trenberth’s theory that the heat is hiding in the deep ocean?? It will be interesting to see how the Climate Establishment deals with that. Wild, a member of that establishment and a scientist with impeccable credentials, cannot be easily dismissed.

John West
August 20, 2013 11:36 am

Mike Abbott says:
“he expresses his belief in the enhanced GHG effect.”
So do I. That doesn’t make me any less skeptical of CAGW. If these ideas hold up he is knocking a great big whole in the warming from the 1950’s being mostly due to GHG’s meme which has resulted in the high sensitivity belief among the alarmists. This in turn would make a low sensitivity much more likely than not and a high sensitivity very unlikely.
Go Dr. Wild (and keep your head down).

August 20, 2013 11:52 am

Mike Abbott: “he expresses his belief in the enhanced GHG effect”
A “belief” is no substitute for science.
Wild’s papers are full of data and science showing changes of .5W/m2/year due to changes in surface solar radiation. Changes of that magnitude dwarf the supposed effect of CO2.

tonyb
Editor
August 20, 2013 12:14 pm

Sunshine hours
In our neck of the West Country (Torbay) we get around 1700 hours of sun per year.
There is quite a proliferation of solar farms round here as a result but this pitiful amount is of course heavily geared towards the summer.
Who (without a large subsidy) would build a 50 acre (50 acres!!!) solar farm that would barely power a torch in the winter when energy is most needed? Of course it is even more needed on a cold winters NIGHT. Wonder how the solar farms will perform then?
The Uk’s energy policy gets dafter by the minute.
tonyb

August 20, 2013 12:28 pm

Can anyone remember “pan evaporation rates”? Is this a retooled version of the “Global Dimming” theory [who was that again?] that we were harangued with 10 years ago, explaining why the CO2 induced warming predicted had not yet come to pass and that as soon as we cleaned up our acts things would suddenly get “much worse”? On the surface of it both versions seem like plausible explanations, which one will gain the most traction with observations?
W^3

August 20, 2013 12:31 pm

As to ‘peer review’ there is this quote, available in Wikipedia, by Richard Horten, editor of the Lancet “But we know that the system of peer review is biased, unjust, unaccountable, incomplete, easily fixed, often insulting, usually ignorant, occasionally foolish, and frequently wrong.”
GW ended before 2001. http://endofgw.blogspot.com/
AGW never was. http://climatechange90.blogspot.com/2013/05/natural-climate-change-has-been.html

geo
August 20, 2013 1:09 pm

I think a lot of us (including me) have been wondering along these lines for many years.

August 20, 2013 1:14 pm

w.w.wygart says:
August 20, 2013 at 12:28 pm
“Can anyone remember “pan evaporation rates”? Is this a retooled version of the “Global Dimming” theory [who was that again?]”
I think it was Hanson who first said that air pollution would warm the surface, and then later came out with the opposite hypothesis. I would think it would depend on the altitude, if it absorbs heat near the surface, the surface warms more, if it absorbs heat further up, then the surface loses out.
Pan evaporation rates are affected by wind speed, which globally have been dropping.

Kelvin Vaughan
August 20, 2013 1:29 pm

Pamela Gray says:
August 20, 2013 at 8:14 am
Quick! Find a virgin!
I thought virgins had become extinct due to global warming?

Scott
August 20, 2013 5:22 pm

Wondering home many actually read the Wild 2012 study. The caption for figure 1 above seems conveniently left out. Click on the link and read it if you haven’t. Seems the Wild study doesn’t propose that increased sunshine during the brightening period has caused the warming but rather the decreased sunshine during the dimming period masked AGW. The last statement is the most telling, “Under these perspectives, only the rapid worldwide implementation of both rigorous greenhouse gas reduction and air quality measures will allow us to minimize adverse climate and health impacts and ensure sustainable living conditions for future
generations on Earth.” When this article is put in its proper context it paints a much different picture.

August 20, 2013 7:41 pm

Scott, I prefer earlier Wild research.
,5 Watts / m2 / year totally overwhelms the supposed CO2 signal.
http://i55.tinypic.com/34qk01z.jpg

richardscourtney
August 21, 2013 12:40 am

old engineer:
Your post at August 19, 2013 at 8:15 pm
http://wattsupwiththat.com/2013/08/19/shocker-global-warming-may-simply-be-an-artifact-of-clean-air-laws/#comment-1395085
says

Sorry Joe, but you didn’t fix it. Zeke was right, the GCM’s do include the effects of atmospheric aerosols. Going back to Hansen, et.al. 1988. In Appendix B of Hansen’s paper, there are 4 things listed as having negative radiative forcings: stratospheric and tropospheric sulfuric acid aerosols, tropospheric desert aerosols, and land albedo.
However, you are right also. They have failed to match reality, but more from overestimating green house gas effects than failing to include aerosols.

Sorry, but NO! That is a misunderstanding.
The GCM’s don’t “include the effects of atmospheric aerosols”. They each use a different value of assumed aerosol cooling as a ‘fiddle factor’ which compensates for each GCM using a unique – and too high – value of climate sensitivity to “green house gas effects”.
It seems I need to post the following yet again.
None of the models – not one of them – could match the change in mean global temperature over the past century if it did not utilise a unique value of assumed cooling from aerosols. So, inputting actual values of the cooling effect (such as the determination by Penner et al.
http://www.pnas.org/content/early/2011/07/25/1018526108.full.pdf?with-ds=yes )
would make every climate model provide a mismatch of the global warming it hindcasts and the observed global warming for the twentieth century.
This mismatch would occur because all the global climate models and energy balance models are known to provide indications which are based on
1.
the assumed degree of forcings resulting from human activity that produce warming
and
2.
the assumed degree of anthropogenic aerosol cooling input to each model as a ‘fiddle factor’ to obtain agreement between past average global temperature and the model’s indications of average global temperature.
More than a decade ago I published a peer-reviewed paper that showed the UK’s Hadley Centre general circulation model (GCM) could not model climate and only obtained agreement between past average global temperature and the model’s indications of average global temperature by forcing the agreement with an input of assumed anthropogenic aerosol cooling.
The input of assumed anthropogenic aerosol cooling is needed because the model ‘ran hot’; i.e. it showed an amount and a rate of global warming which was greater than was observed over the twentieth century. This failure of the model was compensated by the input of assumed anthropogenic aerosol cooling.
And my paper demonstrated that the assumption of aerosol effects being responsible for the model’s failure was incorrect.
(ref. Courtney RS An assessment of validation experiments conducted on computer models of global climate using the general circulation model of the UK’s Hadley Centre Energy & Environment, Volume 10, Number 5, pp. 491-502, September 1999).
More recently, in 2007, Kiehle published a paper that assessed 9 GCMs and two energy balance models.
(ref. Kiehl JT,Twentieth century climate model response and climate sensitivity. GRL vol.. 34, L22710, doi:10.1029/2007GL031383, 2007).
Kiehl found the same as my paper except that each model he assessed used a different aerosol ‘fix’ from every other model. This is because they all ‘run hot’ but they each ‘run hot’ to a different degree.
He says in his paper:

One curious aspect of this result is that it is also well known [Houghton et al., 2001] that the same models that agree in simulating the anomaly in surface air temperature differ significantly in their predicted climate sensitivity. The cited range in climate sensitivity from a wide collection of models is usually 1.5 to 4.5 deg C for a doubling of CO2, where most global climate models used for climate change studies vary by at least a factor of two in equilibrium sensitivity.
The question is: if climate models differ by a factor of 2 to 3 in their climate sensitivity, how can they all simulate the global temperature record with a reasonable degree of accuracy. Kerr [2007] and S. E. Schwartz et al. (Quantifying climate change–too rosy a picture?, available at http://www.nature.com/reports/climatechange, 2007) recently pointed out the importance of understanding the answer to this question. Indeed, Kerr [2007] referred to the present work and the current paper provides the ‘‘widely circulated analysis’’ referred to by Kerr [2007]. This report investigates the most probable explanation for such an agreement. It uses published results from a wide variety of model simulations to understand this apparent paradox between model climate responses for the 20th century, but diverse climate model sensitivity.

Iimportantly, Kiehl’s paper says:

These results explain to a large degree why models with such diverse climate sensitivities can all simulate the global anomaly in surface temperature. The magnitude of applied anthropogenic total forcing compensates for the model sensitivity.

And the “magnitude of applied anthropogenic total forcing” is fixed in each model by the input value of aerosol forcing.
Thanks to Bill Illis, Kiehl’s Figure 2 can be seen at
http://img36.imageshack.us/img36/8167/kiehl2007figure2.png
Please note that the Figure is for 9 GCMs and 2 energy balance models, and its title is:

Figure 2. Total anthropogenic forcing (Wm2) versus aerosol forcing (Wm2) from nine fully coupled climate models and two energy balance models used to simulate the 20th century.

It shows that
(a) each model uses a different value for “Total anthropogenic forcing” that is in the range 0.80 W/m^-2 to 2.02 W/m^-2
but
(b) each model is forced to agree with the rate of past warming by using a different value for “Aerosol forcing” that is in the range -1.42 W/m^-2 to -0.60 W/m^-2.
In other words the models use values of “Total anthropogenic forcing” that differ by a factor of more than 2.5 and they are ‘adjusted’ by using values of assumed “Aerosol forcing” that differ by a factor of 2.4.
So, each climate model emulates a different climate system. Hence, at most only one of them emulates the climate system of the real Earth because there is only one Earth. And the fact that they each ‘run hot’ unless fiddled by use of a completely arbitrary ‘aerosol cooling’ strongly suggests that none of them emulates the climate system of the real Earth.
Richard

richardscourtney
August 21, 2013 12:45 am

Theo Goodwin:
re your post at August 19, 2013 at 8:58 pm.
Yes, I have made a long post which explains your correct point, but – for some unknown reason – it is waiting in moderation.
Richard

Brian H
August 21, 2013 1:32 am

20% ! That’s a sabre-tooth in the living room. Dinner is served!

Keitho
Editor
August 21, 2013 4:19 am

Seems to me that aerosols aren’t THE answer but they are certainly part of it, along with many of the things we discuss here. My take is that the effect of aerosols is a suitable candidate for more research.

Ray C
August 21, 2013 4:43 am

Are the basic ideas about the aerosol loading correct? I think the natural aerosol loading is incorrectly estimated!
According to Natalie Mahowald, the amount of dust in the Earth’s atmosphere has doubled over the last century.
http://www.enn.com/sci-tech/article/42210
http://www.sciencedaily.com/releases/2011/01/110110055748.htm
According to Jasper Kok, (who carries out interesting research on dust aerosol)
http://www.wired.com/wiredscience/2010/12/dust-shatters-like-glass/
Global Circulation Models overestimate the amount of cooling dust by a large factor. And do not account for warming silts!!!
http://sitemaker.umich.edu/jasperkok/files/kok2011_pnas_scalingtheorydustpsd.pdf
“Because clay aerosols produce a strong radiative cooling, the overestimation of the clay fraction causes GCMs to also overestimate the radiative cooling of a given quantity of emitted dust.”
“… On a global scale, the dust cycle in most GCMs is
tuned to match radiative measurements, !!!
such that the overestimation of the radiative cooling of a given quantity of emitted dust has likely caused GCMs to underestimate the global dust emission rate. This implies that the deposition flux of dust and its fertilizing effects on ecosystems may be substantially larger than thought.”
Have they corrected GCMs to account for silts?
So what is it. If they are guessing (tuning to match) the cooling effect of a loading of dust is there more warming from, dark, silt aerosol (missing) or too much emphasis on cooling clay aerosol or is there more dust than they think? (fertiliser)
Has there been an ever increasing amount (getting dustier over the last century) of ‘missed’ silt aerosol which would have a radiative warming effect?

GeorgeTomaich
August 21, 2013 8:45 am

I have a problem with this proposal. This appears to be an urban issue and not a global issue.

August 21, 2013 10:26 am

If global brightening is fact, what now, do we wait until it gets too cold, then light up anything that’s coal fired?
If so, China can continue saving the planet for us. Ö¿Ö

1sky1
August 21, 2013 3:30 pm

What is totally unconvincing about the pollution-driven dimming/brightening explanation of world-wide temperature swings in the latter half of the 20th century is that the Southern Hemisphere, where such pollution was minimal, swung quite coherently and in-phase with the NH, where the pollution was the greatest. Since, there is very little exchange of air masses between the hemispheres, something quite different is manifestly at work.

Keitho
Editor
Reply to  1sky1
August 22, 2013 4:04 am

. . you overlook the enormous amount of forest and savanah that is burned every year in sub-saharan Africa which I understand is similar in South America too. It generates a huge amount of soot and other particulates and goes on from late June to the end of October.

Mike O'Connor
August 22, 2013 11:38 am

There are no good datasets of solar insolation (sunlight reaching the ground) pertaining to the 1950’s or 60’s. Actually, good solar insolation data are hard to come by.
Back in the 1970’s, the days of Jimmy Carter and the Arab oil embargoes, there was a government push toward solar power— just as now, but then of course we didn’t have global-warming activists/profiteers. Then the emphasis was on just coming up with energy so as to not be dependent upon the Arabs. (Would that we had succeeded!)
So records on solar insolation everywhere were of interest, as the records could be used to determine whether a given place was too habitually cloudy for solar power (nowadays it’s put in everywhere, even though it’s feasible nowhere).
Well, the database consisted of bolometric measurements— you measure the temperature of a blackened surface that is exposed to the sky. It was found that the autorities had neglected calibration of the bolometers for decades (they’re not particularly easy to calibrate). And so there was a downward drift in the measurements of insolation due to such things as the black becoming not so black. Or the glass cover suffering a thin-film buildup.
So no, you can’t trust one of these warmer profiteer “scientists” to come up with anything but another publish-or-perish article from time to time.

1sky1
August 22, 2013 5:04 pm

Keitho;
You apparently are unacquanted with those places. In Sub-Saharan Africa June to October is the peak of the monsoon season and there is no widespread burning going on. Dust raised by Harmattan winds during the dry season is the chief source of particulates in that region. Slash and burn agriculture is not a serious issue there. There has been much land-clearing by fire In the Amazon basin in recent decades; however, carbon soot does not stay long in the atmosphere there. In any event, it cannot explain both hemispheres being in sync in their recent temperature swings.

Keitho
Editor
Reply to  1sky1
August 23, 2013 8:43 am

1sky1 . . sorry , the dry season in sub Saharan Africa runs from the end of May at the latest to the end of October. I have watched weeks of nothing but smoke in the air from Mozambique and right across Zimbabwe into northern Botswana. Bush fires are a real thing and they dim the sun bigtime.

1sky1
August 23, 2013 2:45 pm

Keitho:
Sorry, but sub-Saharan Africa is a geographic term that refers properly to the Sahel and the equatorial forest zone along the Gulf of Guinea. You are talking about SE Africa. Nevertheless, your basic argument doesn’t hold, because slash-and-burn agriculture there is not a post-WWII activity; it has been going on for centuries. The inter-hemispheric coherence of the recent multidecadal temperature swings remains unexplained by bush fires that you’ve seen dimming the sun. If anything they should produce dry-season cooling in SE Africa.