A new modeling study from NASA confirms that when tiny air pollution particles we commonly call soot – also known as black carbon – travel along wind currents from densely populated south Asian cities and accumulate over a climate hotspot called the Tibetan Plateau, the result may be anything but inconsequential.
In fact, the new research, by NASA’s William Lau and collaborators, reinforces with detailed numerical analysis what earlier studies suggest: that soot and dust contribute as much (or more) to atmospheric warming in the Himalayas as greenhouse gases. This warming fuels the melting of glaciers and could threaten fresh water resources in a region that is home to more than a billion people.
Lau explored the causes of rapid melting, which occurs primarily in the western Tibetan Plateau, beginning each year in April and extending through early fall. The brisk melting coincides with the time when concentrations of aerosols like soot and dust transported from places like India and Nepal are most dense in the atmosphere.
“Over areas of the Himalayas, the rate of warming is more than five times faster than warming globally,” said William Lau, head of atmospheric sciences at NASA’s Goddard Space Flight Center in Greenbelt, Md. “Based on the differences it’s not difficult to conclude that greenhouse gases are not the sole agents of change in this region. There’s a localized phenomenon at play.”
He has produced new evidence suggesting that an “elevated heat pump” process is fueling the loss of ice, driven by airborne dust and soot particles absorbing the sun’s heat and warming the local atmosphere and land surface. A related modeling study by Lau and colleagues has been submitted to Environmental Research Letters for publication.
A unique landscape plays supporting actor in the melting drama. The Himalayas, which dominate the plateau region, are the source of meltwater for many of Asia’s most important rivers—the Ganges and Indus in India, the Brahmaputra in Bangladesh, the Salween through China, Thailand and Burma, the Mekong across Laos, Cambodia and Vietnam, and the Yellow and Yangtze rivers in China. When fossil fuels are burned without enough oxygen to complete combustion, one of the byproducts is black carbon, an aerosol that absorbs solar radiation (Most classes of aerosols typically reflect incoming sunlight, causing a cooling effect). Rising populations in Asia, industrial and agricultural burning, and vehicle exhaust have thickened concentrations of black carbon in the air.
Sooty black carbon travels east along wind currents latched to dust – its agent of transport – and become trapped in the air against Himalayan foothills. The particles’ dark color absorbs solar radiation, creating a layer of warm air from the surface that rises to higher altitudes above the mountain ranges to become a major catalyst of glacier and snow melt.
- CLICK TO VIEW ANIMATION – Tiny, dark-colored aerosols — specifically black carbon — travel along wind currents from Asian cities and accumulate over the Tibetan Plateau and Himalayan foothills. Seen here as a light brown mass, these brown clouds of soot absorb sunlight, creating a layer of warm air (seen in orange) that rises to higher altitudes, amplifying the melting of glaciers and snow. Credit: NASA/Sally Bensusen Nicknamed the “Third Pole”, the region in fact holds the third largest amount of stored water on the planet beyond the North and South Poles. But since the early 1960s, the acreage covered by Himalayan glaciers has declined by over 20 percent. Some Himalayan glaciers are melting so rapidly, some scientists postulate, that they may vanish by mid-century if trends persist. Climatologists have generally blamed the build-up of greenhouse gases for the retreat, but Lau’s work suggests that may not be the complete story.
Building on work by Veerabhardran Ramanathan of the Scripps Institution of Oceanography, San Diego, Calif., Lau and colleagues conducted modeling experiments that simulated the movement of air masses in the region from 2000 to 2007. They also made detailed numerical analyses of how soot particles and other aerosols absorb heat from the sun.
“Field campaigns with ground observations are already underway with more planned to test Lau’s modeling results,” said Hal Maring who manages the Radiation Sciences program at NASA Headquarters in Washington. “But even at this stage we should be compelled to take notice.”
“Airborne particles have a much shorter atmospheric lifespan than greenhouse gases,” continued Maring. “So reducing particle emissions can have much more rapid impact on warming.”
“The science suggests that we’ve got to better monitor the flue on our ‘rooftop to the world,” said Lau. “We need to add another topic to the climate dialogue.”
h/t to Dr. Roger Pielke Sr.
Related Links:
> The Dark Side of Carbon: Will Black Carbon Siphon Asia’s Drinking Water Away?
> Soot is Key Player in Himalayan Warming, Looming Water Woes in Asia
> Asian Summer Monsoon Stirred by Dust in the Wind
> A Unique Geography — and Soot and Dust — Conspire Against Himalayan Glaciers
Gretchen Cook-Anderson
NASA Earth Science News Team
I am always annoyed to read that glacier retreat could have such a devastating effect on the water resource of people. I think someone should point out the following, especially when the Himalayan glaciers are the subject:
Himalayan glaciers have their maximum melt and run-off in the period from June/July to September/October which coincides with the monsoon rains and thus are often contributing to the flooding of the lower and near coastal lands. So it would be better if the winter precipitation in the Himalayans would flow down the rivers to help the drought – which is most severe in the winter – than being accumulated as snow. The summer flow is often 10 times or more than the winter discharge.
Moreover, before the climate change scare, most scientific papers were studying the seasonal snow melt as the major contributor to the discharge from upstream rivers and not the glacier melt.
I’ll be in the Northern Himalayas next week.
I’ll let you guys know how cold/hot it is when I get back.
So….was it CO2 black or soot black?…changing threads as Tarzan, from tree rings to burnt amazon trees?
Something more credible to sign on?
“mumbojumbo mumbojumbo new modeling study mumbojumbo detailed numerical analysis mumbojumbo mumbojumbo…could threaten…more than a billion people… mumbojumbo…beginning each year in April and extending through early fall…melting coincides with the time when…soot and dust…are most dense in the atmosphere…”
And coincides with Spring, when stuff melts.
O.T.
On Spaceweather.com:
“BIG NEW SUNSPOT: Just yesterday, sunspot 1035 was nearly invisible. Today, it is as wide as seven planet Earths. The fast-growing active region burst into view on Dec. 14th with a magnetic polarity that clearly identifies it as a member of new Solar Cycle 24. If the expansion continues apace, it could soon become the largest sunspot of the year.”
I don’t understand. Does this mean the forcing diagram used by the IPCC is wrong? Surely not!
I am not saying that there might not be something to this, but have we not seen the following line before
“Field campaigns with ground observations are already underway with more planned to test Lau’s modeling results,”
Will there be any “adjustments”
Oh…. and is this another embryonic environmental scare? Will the inevitable conclusion be:
I’m just thinking out loud you understand.
I prescribe a course of leeches…….
So these countries that kick up all that dust and blow all that soot into the air want us to pay for the alleged damage that they are causing locally?
There’s a problem with dust and soot warming the place up.
The clouds of dust from N. Africa and Russia kicked up in 1941/42 from all that mechanized movement plus the burning of whole areas (scorched earth) and bombing didn’t warm up anything. It got colder.
Never mind.
Might as well play tapes of Iraqi Bob. At least that guy was good for a laugh.
It’s good to highlight that there are legitimate pollution concerns that adversely affect climate. Too often I think that people find themselves falling into 1 of 2 camps: CO2 and all industrialization is evil, or all CO2 and industrialization are good.
In my opinion, those who really care about the environment should be encouraging manufacturing to be domestic. In the US (and I imagine Europe and Australia) there are lots of environmental controls on what’s done. Simply put, if you want something to be made with the least environmental impact – make it in the West. It’s irresponsible to export our pollution to other countries.
Regards
Jack
The thing I see over looked by the comments is that they are not just relying on Computer models, they are actually going to check to see if the models are right (unlike a certain CO2 theory).
Here is the quote:
“Field campaigns with ground observations are already underway with more planned to test Lau’s modeling results,” said Hal Maring who manages the Radiation Sciences program at NASA Headquarters in Washington. “But even at this stage we should be compelled to take notice.”
When was the last time you heard the team PUBLICLY state that they were going to test the models against observed results. Egads they are checking the models accuracy! How novel a concept!
SidViscous (12:22:34) :
see if you can get a sample of that purple stuff that’s swallowing up the globe for analysis
…there should be some ‘New Rules’ or something when it comes to science reporting. such as 1) when you make a neato animation with pretty colors and dramatic illustrations that are a gross misrepresentation of reality, put a disclaimer/scale in there that says ‘these purple pixels are a billion times bigger than what I’m trying to represent from my imagination’ and 2) put a link to a compilation of your data and references that led to make such broad, sweeping conjecture and conclusions so we don’t have to duplicate effort and spend the next 2 years digging it up. I appreciate the visualizations as much as the next guy, and they can be useful, but this stuff qualifies more as propaganda than anything else.
This report seems utterly specious to this non-scientist, but having spent several months in Nepal over two years, I will say that the burning of firewood and yak dung is pervasive and smelly. It took weeks to get that smell out of my nostrils!
But the idea that it’s melting the Khumbu Icefall is preposterous.
Something only the eco-trekking greenies of Germany, Oz, and France would believe.
I wish they’d show us what’s happening to all that soot coming off the coast of China. My guess is that a lot of it winds up in the arctic. That certainly would explain a great deal of the melt.
RC has a post up about the CRU data and arrive at 0.54 degree increase /century… I don’t expect my comment will be posted there, so I am gonna post it here..
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DB says:
Your comment is awaiting moderation.
15 December 2009 at 3:30 PM
If the CRU number is 0.54° of warming per century and half of the warming is tied to things other than CO2: namely black carbon, methane, land use changes, UHI effects, and various CFCs, then carbon dioxide is only responsible for 0.27°? That is really mind boggling that the big bad bully of C02 is only good for a quarter of a degree. Am I missing something here?
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DB says:
Your comment is awaiting moderation.
15 December 2009 at 3:33 PM
C02 is only half of the constituents of the warming. We can’t blame all of that .0.54°/century on carbon dioxide. So half of .54° = 0.27° of warming due to C02 over a century?”
Thanks –not a troll– 🙂
For years I have said that the money being dissipated chasing CO2 could have been used to diminish soot and actually have made a difference.
rbateman (11:00:23) :
Put the smoke through a water bath trap. How hard it that?
Deutz does it on their permissible diesel engines, last I looked
I long ago owned part of a boat builder. We used a waterfall to capture dust from sanding and cutting or trimming boat parts.
Now road builders sprinkle water on dirt to reduce dust. It is called “fugitive waste”.
Agricultural fires in the third world, India and China are the biggest source of pollution worldwide. MODIS on the satellite AQUA has photos of some of the bigger smoke signals — http://modis.gsfc.nasa.gov/
Fire Mapper has a daily update of fires around the globe using similar sat images — http://firefly.geog.umd.edu/firemap/
You wonder why the alarmists aren’t all over this, well maybe not, how would they pay for anything.
here are some papers on black carbon aka soot. That there would be some melting if there were huge clouds of this stuff makes sense to me.
http://www.easternsnow.org/proceedings/2007/boggild_luthje_holmes.pdf
http://www.gcrio.org/OnLnDoc/pdf/black_soot.pdf
http://dust.ess.uci.edu/smn/smn_snw_drt_iamas_200707.pdf
[you need a valid email address to continue to comment here ~ ctm]
Wasn’t there a study recently (within the last year or two) that explained that the visible brown haze over the Indian sub-continent was keeping temperatures there cooler than they otherwise would be expected to be? Don’t you all remember Nuclear Winter?
The warm-mongers have been promoting the expansion of soot-producing energy methods.
See: http://www.appinsys.com/GlobalWarming/BiomassBurning.htm
No surprise at all. Soot is mankinds greatest health threat from combustion, always has been. People make a big deal about NO, CO, and other noxious crap coming out of cars in big cities. While those certainly are carcinogens, the soot that gets caught in your lungs never really leaves you.
Is this another weird scientific term? flue??!!
soot is soot, don’t make it into a disease