NOAA study suggests aerosols might be inhibiting global warming

July 22, 2011 by Bob Yirka report
Sources of aerosols reach the stratosphere from above and below, as shown in the graph. Sulfur dioxide (SO2), carbonyl sulfide (OCS), and dimethyl sulfide(DMS) are the dominant surface emissions which contribute to aerosol formation. (Credit: NOAA)

( -- A new study led by the U.S, National Oceanic and Atmospheric Administration (NOAA) shows that tiny particles that make their way all the way up into the stratosphere may be offsetting a global rise in temperatures due to carbon emissions. And while scientists cannot yet say with any certainty where exactly the particles are coming from, they are saying that they have confidence that such particles have likely muted global temperature gains by as much as a third of what they would have been. They team, led by John Daniel, a physicist at the NOAA Earth System Research Laboratory (ESRL) in Boulder, CO, has published their results in Science.

The new research has focused on aerosols, the tiny solid or liquid particles that exist in the atmosphere that can affect , such as when Mt. Pinatubo in the Philippines, erupted in 1991 causing a worldwide average decrease in temperature of 1 degree Celsius for more than a year. The cooling is not the result of the ash, notes co-author Susan Soloman, but from the sulfur dioxide that is thrust all the way up into the stratosphere, where it oxidizes and adds to the sun reflecting properties of other already existing particles.

The team focused on the most recent decade because of the relative absence of , giving them a more clear environmental view of how much impact minor volcanic eruptions and human activities have on the amount of aerosols in the atmosphere and thus global temperatures. To find out what was going on, they used both ground based data and information from satellites such as Cloud-Aerosol Lidar and Infrared Pathfinder (Calipso), to measure the amount of aerosols in the atmosphere and at what altitudes.

NOAA has released a statement outlining the results of the study, and in it Daniel, says, “stratospheric aerosol increased surprisingly rapidly in that time, almost doubling during the decade,” which forms the basis of the teams conclusions that such aerosols are responsible for the slowdown in increased temperatures that scientist around the world have been expecting due to greenhouse gas emissions.

Lidar instruments - pointing up from the ground or down from satellites - use reflected light to measure the amounts of particles and their locations, which can influence climate. (Credit: CIRES/NOAA)

The surprising aspect of the study is the large amount of aerosols found during a period when there weren’t any giant volcanoes going off, which leads researches to wonder if the aerosols are from the combined effects of multiple small eruptions, or human activity, such as the particles emitted from coal fired power plants, particularly in Asia, where such plants have multiplied in recent years. One thing the research is not able to tell us is what impact aerosols will likely have in the future, because of the uncertainty of their origin, which means there is no way to tell at this point if there will be more, or less of them, which means scientists can only guess if the temperature muting will continue to offset global warming from current and future .

Explore further: The mystery of particles

More information: The Persistently Variable “Background” Stratospheric Aerosol Layer and Global Climate Change, Science DOI:10.1126/science.1206027

Recent measurements demonstrate that the “background” stratospheric aerosol layer is persistently variable rather than constant, even in the absence of major volcanic eruptions. Several independent data sets show that stratospheric aerosols increased in abundance since 2000. Near-global satellite aerosol data imply a negative radiative forcing due to stratospheric aerosol changes over this period of about –0.1 W/m2, reducing the recent global warming that would otherwise have occurred. Observations from earlier periods are limited but suggest an additional negative radiative forcing of about –0.1 W/m2 from 1960 to 1990. Climate model projections neglecting these changes would continue to overestimate the radiative forcing and global warming in coming decades if these aerosols remain present at current values or increase.

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3.5 / 5 (6) Jul 22, 2011
I hope hair from the 80s comes back to save us from global warming!
2.7 / 5 (19) Jul 22, 2011
Something is inhibiting global warming? This is typical leftist advocacy "journalism". The genuine journalist would write a story about "something is inhibiting global warming" or "the predicted global warming is not happening" (that's being very kind). Instead, we get the story from the excuse-maker's point of view. How about simply reporting on the "warming" or lack thereof, people? Somehow that story never gets written. It is a disgrace.
2.1 / 5 (15) Jul 22, 2011
If more aerosols cause cooling (or prevent warming) then less aerosols caused by US/UK/European/Japan clean air efforts may have caused the warming in the first place.
2.4 / 5 (12) Jul 22, 2011
The cooling effect of micro-particulates and aerosols have been known for more than 50 years. To say that they have not been factored into climate change models adequately announces just how incomplete - if not incompetent current climate and climate change models really are. Next we'll be hearing that evaporative cooling - which responds directly and proportionately to additional hot weather has also been inadequately accounted for. And, in case it failed register, warming trends produce drying which results in far more fires and smoke - cooling micro-particulates and aerosols - not just volcanos.
1.7 / 5 (6) Jul 22, 2011
NOAA is trying to mitigate the use of chemtrails; they're about as useful as the EPA with their girly-scream-crys against big corporate polluters, "oh! pwease don't poison de environment, kine sir! or we showe be tewwibry diffappointod!"
4.3 / 5 (3) Jul 22, 2011
Well it seems like a good thing that there is some negative raditative forcing. Unfortunately CO2 lingersm for thousands of years and at the worlds burn-rate accumulates exponentially. Where as particulate settles in decades and so will not provide cover to global warming. People, we have to stop the quickly burning (1)Coal, (2)Oil; Our planets sequestered CO2 stock.
4.8 / 5 (5) Jul 22, 2011
If you shine high-powered lasers into the sky, you'll burn out the retinas of the angels looking down on us.
2.5 / 5 (6) Jul 22, 2011
Unfortunately CO2 lingers for thousands of years and at the worlds burn-rate accumulates exponentially.

Have you even looked at the carbon cycle? The net change from year to year is a small fraction of the total amounts 1) released into and 2) removed from, the atmosphere. When we run out of coal to burn, or (and I definitely hope) the human race gets smart enough to stop burning coal, the atmospheric levels of CO2 will return to normal within a century.

What is normal? How quickly? How will it affect global temperatures? All those are questions which atmospheric models are not yet good enough/validated to be able to answer.
1 / 5 (7) Jul 22, 2011
Since "mother nature" removes 40% of man made carbon from the atmosphere no matter what ppm CO2 is already there, if no CO2 is produced all manmade CO2 will disappear in less than 5 years.
4 / 5 (8) Jul 22, 2011
You denier fanatics are missing the point - this study doesn't say that there was no warming, rather that there was a "slowdown in increased temperatures". The stratospheric aerosols cool the planet more than accounted for in the models, and that the models need to be revised to include this effect.

Warming is definitely occurring, unfortunately. The 2000s were undisputedly the hottest decade in recorded history.
3.6 / 5 (7) Jul 23, 2011
Exactly my thought quantum. ;-] The global warming is there. No point disputing that.
2.3 / 5 (15) Jul 23, 2011
Deniers? Is that the label of choice these days? Deny what? Deny that there is global warming? Deny that the warming is not natural? Deny that the warming is not inevitable? Deny that we have the ability technologically, economically, politically, globally, to effectively stop global warming? Deny the solution to global warming is cheaper than adapting to whatever effects global warming produce? Deny that those that call us "Deniers" truly have a comprehensible understanding of all the factors and science behind global warming? Deny that doing what is intuitively "green", may not actually be doing accomplishing anything? I'm sure I fall into one or more of those categories, along with a fair portion of the global informed. Go ahead and call me a Denier. It's political anyway.
3 / 5 (10) Jul 23, 2011
Mountain guy - my response to you is that the term deniers refers to the war on science - and those who wish to replace science with superstition and/or politics. You claim to be part of 'the global informed'. I am not sure what this means - but in the U.S.- 40% of the folks believe the earth was created in the last 10,000 years http://www.huffin...078.html In fact here in Oklahoma it is probably more like 90% It is hard to have a scientific debate in a culture with that level of ignorance - but we try. For an interesting look at science vs. deniers - see http://www.treehu...ideo.php David.
2.5 / 5 (12) Jul 23, 2011
my response to you is that the term deniers refers to the war on science

The scientific method is that you come up with a theory and then try as hard as you can to prove it wrong. Skepticism is the heart of modern discovery. True scientists in fields such as astronomy understand that. Climate study has two camps, the larger camp is not scientific in the way I just described. They are funded by special interest groups and motivated by social agendas. The smaller group is called deniers, but they are the ones using the scientific methhod of questioning themseves and others.

By the way, the slowdown of warming we have now is because of decadal ocean cycles, just as the warming (most of it) was also due to decedal ocean cyycles.

Expect 2012 to be cooler than average.

I'm not sure that's right, but that's one theory that's being thrown out right now by deniers who actually question their own work.
4.4 / 5 (7) Jul 23, 2011
"Skepticism is the heart of modern discovery." You are just plain wrong gswift. Skepticism is an important attitude for all of us - I conccurr - but not the heart of modern discovery - that is false. Marconi - when he was experimenting with radio waves - did not say 'I have to prove that radio waves do not work as a means of transmitting data.' He was experimenting - and trying to see what happened. Rigorous scientific method was critical - so that others could replicate his experiments - and either validate them - or question them. Scientists who collect data on the glaciers - are not trying to prove that the glaciers are not melting - they are simply collecting data. There are special interests - and biased groups in all quarters. This is why it is critical to back out of things - and simply ask "what does the data show". It shows the climate is warming - the glaciers are melting - the ice sheets are melting - the ocean levels are rising.Ur opinion and mine are irrelevant.
3.7 / 5 (3) Jul 23, 2011
'Expect 2012 to be cooler than average.' Could you be more specific about the word average? Are we talking average over the last 100 years, or over the last decade? I would love for you to take a look at this temperature record - and tell me that 2012 is going to be cooler than the 130 year average.http://data.giss....g.A2.gif And if you are talking about the 10 year avg. - surely you know that is just noise? But I will watch your prediction with interest. Do you have references for claiming most of the warming is due to ocean cycles?
1.6 / 5 (7) Jul 23, 2011
I could lecture you about GISS and Gavin Schmidt, but I won't.

No, I don't have a good reference, aside from the NINO3-4 record which is readily available at NCDC. I'm sure you can find it?

The super-nino of last year was predicted by Hansen of Penn State, and the warming that resulted was also predictable. NOw we're already in a cool PDO state, as you can clearly see from the weather patterns here in the US. They are saying that ENSO looks like it'll stay neutral for the forseeable future, and maybe go negative again. The AMO is also due to go cold any time now. If we get a tripple play on all three of those, then we'll be below the 130 year average. If we only get two out of three, then we'll be at 1970's levels. If only one out of three, then we're back to the ten year average low you mentioned.

I assume that you knew that all three of those have been mostly warm for the past 100 years. Even when one of them went cool, it was short and the other two were warm. Data speaks
1.7 / 5 (7) Jul 23, 2011
As for skepticism not being part of science, I respect your view, and I appreciate the way you eloquently argue your point (which is why I 5'd you). I do however disagree in principle. Einstein vehemently disagreed with the way many people took the meaning of his math terms litterally, but after decades of trying to prove them wrong, we have found that they continue to be correct. The whole point of CERN is to try to shoot holes in the theories of relativity and/or quantum physics, to try to see what parts of them are right and wrong. Maybe the term skepticism is where you and I disagree. I just used that word because that's what la warmistas call people like me. I am simply looking at the data and saying that there's obvious flaws in a bunch of the climate theories. Their ability to predict is extremely limited, no matter what the IPCC says. Show me a climate model that predicts what the AMO is going to do in two years, or ENSO.
1.6 / 5 (7) Jul 23, 2011
lol, I see that Joe Bastardi is saying the same thing I was saying. I wouldn't post a link to him as a source here though. I'll stick with NCDC as my sorce, and I maintain that the data speaks for itself, though there are not published studies looking at it. Isn't that strange? The data seems so clear, but there's no studies from those people? Hmmmmmm.
1 / 5 (1) Jul 23, 2011
OK - last post on this thread. "I maintain that the data speaks for itself, though there are not published studies looking at it" I would have to ask -what data are you referring to? If there are no published studies - from a scientific perspective - there is no data. How can any one validate, or challenge your data - if you have not published? It is not part of the scientific record. To argue that the data is clear - but there is no published studies, is contradictory. Thanks for the exchange. David.
1.7 / 5 (6) Jul 23, 2011
I would have to ask -what data are you referring to? If there are no published studies - from a scientific perspective - there is no data.

NCDC publishes a record of the ocean states. It's easily accessed at the NOAA web sites. the ENSO index, AMO and PDO record are all published. The data is there for anybody who wants to look at it. A published study with conclusions based on the data is an entirely different matter.

How can any one validate, or challenge your data - if you have not published?

That happens all the time. There have been numerous corrections to the UAH satellite temperature record over time, with no published papers. The data is subject to constant review, regardless of publication in journals. Publication isn't limited to journals, you know. Most data that's collected on a regular basis, such as daily weather, doesn't ever get into a journal. That doesn't mean that I can't look at the data and interpret it, and you can too.
2.1 / 5 (7) Jul 23, 2011
In stead of journal papers, the official sources tend to do periodical reports, such as the NCDC state of the climate report every month. That doesn't mean that there's no data. lol. Put the journal down. Step away slowly. Now, put your hands firmly on the keybord and look up the raw data. Now, tell yourself that there is data, and repeat it several times. :)

All kidding aside, if you can't find the ENSO index record then you aren't even trying. The data is free and public. Go look man.
2.5 / 5 (11) Jul 24, 2011
Burn more Coal. Make electricity too cheap to meter. Watch the economy grow. Enjoy true wealth creation.

Or sit in the dark and freeze.
1 / 5 (4) Jul 25, 2011
but not the heart of modern discovery - that is false. Marconi - when he was experimenting with radio waves - did not say 'I have to prove that radio waves do not work as a means of transmitting data.'

One more thing about that statement. You aren't talking about discovery in that example. That is applied physics, invention, engineering, or tool-making. The basic physics behind his work had already been done by people long before him. Electromagnetics was already a well established field of science theory by the time he figured out a way to artificially broadcast and recieve them for communication. When I said that skepticism was the heart of discovery, I was talking about fundamental science, not applied science or engineering based on those fundamental principles. When Newton worked out his calculus and laws of motion, it wasn't until Einstien questioned them that he came up with a better theory.
1 / 5 (4) Jul 25, 2011
Do not forget, mates, that the largest single source of this mystery pollution is from the legendary farting kangaroos of Australia. The Oz government is even now in the track to save the world from 'roo farts by hunting down and killin' those extremely dangerous destroyers of our fartin' planet. I think that I will go there as a tourist and find out that the real reason that the 'roos fart so much is that they are stealin' chili from Aussie backyard barbies. All those rich bar-b-qued beans and shrimp and stuff make the kangaroos fart MUCH more, makin green and brown gas clouds over major Oz cities....haw..haw..haw!
2 / 5 (4) Jul 25, 2011
Burn more Coal. Make electricity too cheap to meter. Watch the economy grow. Enjoy true wealth creation.

Or sit in the dark and freeze.

And just watch the world boil over from global warming. Extinction and death. Nice call POS.
1 / 5 (3) Jul 25, 2011
The super-nino of last year was predicted by Hansen of Penn State, and the warming that resulted was also predictable. NOw we're already in a cool PDO state, as you can clearly see from the weather patterns here in the US.

Bull to the max guy. The PDO is crap theory that only looser believe in. The nino's are controlled by global warming now. In fact, the Nino's and Nina's will never be the same for millions of years now, thanks to global warming.

1 / 5 (4) Jul 28, 2011
Here's a new study from University of Alabama which suggests that the reason the atmosphere isn't warming as much as models predict is because the models are wrong in a very fundamental way. In a nutshell it says that satellite observations show that the Earth sheds heat faster than the models (and theory) predict. Here's a link to the study published in Remote Sensing, (it'll never be reported on here at Physorg because they only publish pro-agw articles):


As with any new and contradictory study, I would view the article with extreme caution. Yes, I'm skeptical of the skeptics too.

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