Posted on 04/27/2012 9:34:59 AM PDT by Ernest_at_the_Beach
From the Harvard School of Engineering and Applied Sciences
Warming hole delayed climate change over eastern United States
April 26, 2012
50-year model suggests regional pollution obscured a global trend
CONTACT: Caroline Perry, (617) 496-1351
Cambridge, Mass. April 26, 2012 Climate scientists at the Harvard School of Engineering and Applied Sciences (SEAS) have discovered that particulate pollution in the late 20th century created a warming hole over the eastern United Statesthat is, a cold patch where the effects of global warming were temporarily obscured.
While greenhouse gases like carbon dioxide and methane warm the Earths surface, tiny particles in the air can have the reverse effect on regional scales.
What weve shown is that particulate pollution over the eastern United States has delayed the warming that we would expect to see from increasing greenhouse gases, says lead author Eric Leibensperger (Ph.D. 11), who completed the work as a graduate student in applied physics at SEAS.
For the sake of protecting human health and reducing acid rain, weve now cut the emissions that lead to particulate pollution, he adds, but these cuts have caused the greenhouse warming in this region to ramp up to match the global trend.
At this point, most of the catch-up warming has already occurred.
The findings, published in the journal Atmospheric Chemistry and Physics, present a more complete picture of the processes that affect regional climate change. The work also carries significant implications for the future climate of industrial nations, like China, that have not yet implemented air quality regulations to the same extent as the United States.
Observed change in surface air temperature between 1930 and 1990. Observations are from the NASA GISS Surface Temperature Analysis. Image courtesy of Eric Leibensperger.
Until the United States passed the Clean Air Act in 1970 and strengthened it in 1990, particulate pollution hung thick over the central and eastern states. Most of these particles in the atmosphere were made of sulfate, originating as sulfur emissions from coal-fired power plants. Compared to greenhouse gases, particulate pollution has a very short lifetime (about 1 week), so its distribution over the Earth is uneven.
The primary driver of the warming hole is the aerosol pollutionthese small particles, says Leibensperger. What they do is reflect incoming sunlight, so we see a cooling effect at the surface.
This effect has been known for some time, but the new analysis demonstrates the strong impact that decreases in particulate pollution can have on regional climate.
The researchers found that interactions between clouds and particles amplified the cooling. Particles of pollution can act as nucleation sites for cloud droplets, which can in turn reflect even more sunlight than the particles would individually, leading to greater cooling at the surface.
The researchers analysis is based on a combination of two complex models of Earth systems. The pollution data comes from the GEOS-Chem model, which was first developed at Harvard and, through a series of many updates, has since become an international standard for modeling pollution over time. The climate data comes from the general circulation model developed by NASAs Goddard Institute for Space Studies. Both models are rooted in decades worth of observational data.
Since the early 20th century, global mean temperatures have risenby approximately 0.8 degrees Celsius from 1906 to 2005but in the U.S. warming hole, temperatures decreased by as much as 1 degree Celsius during the period 19301990. U.S. particulate pollution peaked in 1980 and has since been reduced by about half. By 2010 the average cooling effect over the East had fallen to just 0.3 degrees Celsius.
Such a large fraction of the sulfate has already been removed that we dont have much more warming coming along due to further controls on sulfur emissions in the future, says principal investigator Daniel Jacob, the Vasco McCoy Family Professor of Atmospheric Chemistry and Environmental Engineering at SEAS.
Jacob is also a Professor of Earth and Planetary Sciences at Harvard and a faculty associate of the Harvard University Center for the Environment.
Besides confirming that particulate pollution plays a large role in affecting U.S. regional climate, the research emphasizes the importance of accounting for the climate impacts of particulates in future air quality policies.
Something similar could happen in China, which is just beginning to tighten up its pollution standards, says co-author Loretta J. Mickley, a Senior Research Fellow in atmospheric chemistry at SEAS. China could see significant climate change due to declining levels of particulate pollutants.
Sulfates are harmful to human health and can also cause acid rain, which damages ecosystems and erodes buildings.
No one is suggesting that we should stop improving air quality, but its important to understand the consequences. Clearing the air could lead to regional warming, Mickley says.
Leibensperger, Jacob, and Mickley were joined by co-authors Wei-Ting Chen and John H. Seinfeld (California Institute of Technology); Athanasios Nenes (Georgia Institute of Technology); Peter J. Adams (Carnegie Mellon University); David G. Streets (Argonne National Laboratory); Naresh Kumar (Electric Power Research Institute); and David Rind (NASA Goddard Institute for Space Studies).
The research was supported by the Electric Power Research Institute (EPRI) and the U.S. Environmental Protection Agency (EPA); neither EPRI nor the EPA has officially endorsed the results. The work also benefited from resources provided by Academic Computing Services at SEAS.
fyi
There are so many lies, scams and junk science in the “climate change” area that even the “experts” are baffled and confused. Nobody knows what the hell is going on, if anything.
And they laughed at medieval monks debating how many angels could fit on the head of a pin.
The whole scam is going down the Gore Hole.
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Willis Eschenbach says:
So their claim is that the temperature drop in northern Mexico, and New Mexico, is because of aerosols?
Egads usually its models all the way down, but this seems to be blind folks all the way down.
w.
The Gore Hole.....
One schmuck grad student dutifully doing his duty to his supervisor so he can get his PhD and get on with his career, and this is the dreck that results.
IT’S FUNDING TIME AT THE UNIVERSITIES: Oh yeh, I must have overlooked how those tiny polution particles form a wormhole that leads to cooling. I think this merits further funds to make a thorough study. This is how the frauds infested in the socialist democrat left make their living. AGW is dying. Watch for the next massive diaster conjured up that needs to be studied. WATER POLLUTION
Conclusion - the Trillion dollars or so spent on stack scrubbers and emission controls in the last four decades has not prevented our inevitable, impending human caused doom. Therefore we need to impose Trillions in new taxes to further environmental justice.
Here is a model that supports Global Warming. She is into "finding herself" (as you can see) and believes the capital of Africa is Kenya. Her hopes for mankind are to find a cure for Dress Tape Rash and to release Mother Gaia's 7th chakra.
AGW may be dying, but it will live on in the Big Giant Brains of the left and the media who love them for decades to come. The question is, will they prevail in congress. So far, they look like they have plenty of life left.
Could we send them down a wormhole instead of a warmhole?....All of those Harvard types....
She has a written excuse.
And you wrote it not her! lol
It's the Gore Hole!
It devours more brains than all the Zombies in Haiti.
BTTT.
Oh yumma,....I would help her.
I might have to be ashamed of myself.
She needs warmth...but...well you know...
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