NASA Finds Soot Has Impact on Global Climate

NASA Earth Observatory ^ | May 13, 2003

[cogitator]

NASA Finds Soot Has Impact on Global Climate

A team of researchers, led by NASA and Columbia University scientists, found airborne, microscopic, black-carbon (soot) particles are even more plentiful around the world, and contribute more to climate change, than was previously assumed by the Intergovernmental Panel of Climate Change (IPCC).

The researchers concluded if these soot particles are not reduced, at least as rapidly as light-colored pollutants, the world could warm more quickly.

The findings appear in the latest issue of the Proceedings of the National Academy of Sciences. It is authored by Makiko Sato, James Hansen and others from NASA's Goddard Institute for Space Studies (GISS) and Columbia University, New York; Oleg Dubovik, Brent Holben and Mian Chin of NASA's Goddard Space Flight Center, Greenbelt, Md.; and Tica Novakov, Lawrence Berkeley National Laboratory, Berkeley, Calif.

Sato, Hansen and colleagues used global atmospheric measurements taken by the Aerosol Robotic Network (AERONET). AERONET is a global network of more than 100 sun photometers that measure the amount of sunlight absorbed by aerosols (fine particles in the air) at wavelengths from ultraviolet to infrared. The scientists compared the AERONET data with Chin's global-aerosol computer model and GISS climate model, both of which included sources of soot aerosols consistent with the estimates of the IPCC.

The researchers found the amount of sunlight absorbed by soot was two-to-four times larger than previously assumed. This larger absorption is due in part to the way the tiny carbon particles are incorporated inside other larger particles: absorption is increased by light rays bouncing around inside the larger particle.

According to the researchers, the larger absorption is attributable also to previous underestimates of the amount of soot in the atmosphere. The net result is soot contributes about twice as much to warming the world as had been estimated by the IPCC.

Black carbon or soot is generated from traffic, industrial pollution, outdoor fires and household burning of coal and biomass fuels. Soot is a product of incomplete combustion, especially of diesel fuels, biofuels, coal and outdoor biomass burning. Emissions are large in areas where cooking and heating are done with wood, field residue, cow dung and coal, at a low temperature that does not allow for complete combustion. The resulting soot particles absorb sunlight, just as dark pavement becomes hotter than light pavement.

Both soot and the light-colored tiny particles, most of which are sulfates, pose problems for air quality around the world. Efforts are beginning to reduce the sulfate aerosols to address air quality issues.

"There is a pitfall, however, in reducing sulfate emissions without simultaneously reducing black carbon emissions," Hansen said. Since soot is black, it absorbs heat and causes warming. Sulfate aerosols are white, reflect sunlight, and cause cooling. At present, the warming and cooling effects of the dark and light particles partially balance.

This research continues observations of global climate change. It was funded by NASA's Earth Science Enterprise. The Enterprise is dedicated to understanding the Earth as an integrated system and applying Earth System Science to improve prediction of climate, weather, and natural hazards using the unique vantage point of space.

[cogitator]

This is pretty significant, because Third World countries emit considerably more black soot pollution than modern industrialized nations, and control of these emissions can be pushed both for climate and public health reasons.

[KayEyeDoubleDee]

I believe absolutely nothing with which James Hansen is associated. The guy is more or less the orginal global warming fear monger.

[facedown]

Ditto that.

[LiteKeeper]

readlater

[dirtboy]

The researchers concluded if these soot particles are not reduced, at least as rapidly as light-colored pollutants, the world could warm more quickly.

Then why did global temps DROP after the eruption of Mt. Pinatubo? Sometimes dese guys just don't make sense...

[RightWhale]

Then why did global temps DROP after the eruption of Mt. Pinatubo?

What kind of particulates did this volcano emit? Light or dark?

[paulk]

Totally bogus because they think the public doesn’t know any physics. Yes, black does absorb more radiation due to black’s higher emissivity, but due to the same emissivity, black also radiates more – sending atmospheric heat back out into space. (This is the same reason heatsinks are black – it helps them radiate heat)

[Eala]

There was an article on this in the Wall Street Journal last week. One interesting item there, not repeated here, was that most of the darker particulates come out of developing countries, whereas most of the lighter particulates were coming out of North America.

[Eala]

That would be true in a vacuum, but in the atmosphere you've got conductivity to deal with.

[Gary Boldwater]

Shucks! I just traded in the SUV for a Yak!

[KC_for_Freedom]

There was an article on this in the Wall Street Journal last week. One interesting item there, not repeated here, was that most of the darker particulates come out of developing countries, whereas most of the lighter particulates were coming out of North America.

So why should we believe another article about global warming? Global warming is always about the US and the West having too much wealth and the third world countries catching up. Read the Kyoto accords. I wish they would call this world socialism instead of science. It corrupts both houses.

[Maceman]

At present, the warming and cooling effects of the dark and light particles partially balance.

So it's not really a problem then, is it?

[Eala]

So why should we believe another article about global warming? Global warming is always about the US and the West having too much wealth and the third world countries catching up. Read the Kyoto accords. I wish they would call this world socialism instead of science. It corrupts both houses.

I think there's a difference between scientific research and politics. You are quite correct about "global warming" in the political realm -- there it is assumed a priori that global warming is occurring, that the cause is "greenhouse gas" emissions, and that the cure is to impoverish the West.

But in the scientific realm the issues are: Do we have historical data that shows that "global warming" is even happening? What are the factors that keep temperatures balanced -- or that let them shift around? I don't have any problem with real, peer-reviewed, etc. research into climate issues. I'd like to see more.

[sergeantdave]

Soot is a product of ...biomass burning.
Yes!!!
Think I'll go fire up the barbecue and singe a steak.

[Tribune7]

Nukes are the answer. bump

[edwin hubble]

"Then why did global temps DROP after the eruption of Mt. Pinatubo? Sometimes dese guys just don't make sense...
"

Yes, They should have made this more clear. (they didn't).

Aerosol droplets high in the upper atmosphere reflect sunlight, and soot high in the atmosphere would do the same: a cooling of climate after a violent eruption.

But...soot on or near ground level would re-radiate infrared: warming.

[Publius6961]

What's next?
NASA Finds Water is Wet?

The real news is that some morons have just discovered soot.
It never existed prior to ummm 1890.
Isn't that when the automile was invented?

Dingbats!

[Prodigal Son]

This is pretty significant, because Third World countries emit considerably more black soot pollution than modern industrialized nations, and control of these emissions can be pushed both for climate and public health reasons.

Aye.

Politics Stalls Global Warming Research

As much as half of any artificial global warming that may be due to human activity is caused by the long-distance travel of airborne soot and similar pollutants, says meteorologist James R. Mahoney, assistant secretary of commerce and coordinator of climate change research for the Bush administration.

But research into the phenomenon is being stalled by the politics of global warming, as India in February 2003 persuaded the United Nations Environment Program to drop research efforts. The United States objected to the proposed 1997 Kyoto climate change protocols because they did not require mandatory reductions in emissions of so-called greenhouse gases by developing countries. Indian officials are reported to be concerned that such research bolsters the U.S. case.

The two-mile thick, continent-size cloud over the Indian Ocean -- dubbed the "Asian Brown Cloud" -- was discovered in 1999 by Indian scientist Veerabhadran Ramanathan.

• The reigning theory of "aerosols" -- airborne particles such as soot -- was that they soon drop from the sky, leaving the earth's atmosphere relatively pristine.
• Scientists previously believed only greenhouse gases such as carbon dioxide could be carried by prevailing winds for thousands of miles from their source.
• But Ramanathan's six-week, $25 million experiment discovered the cloud -- at some points more than 1,000 miles from the source.
• The research suggests that the cloud could reduce sunlight hitting the earth in that area by as much as 15 percent and cut rainfall over much of Asia by up to 40 percent.

Asian pollution contains dark soot from hundreds of millions of dung-fueled cooking fires and inefficient coal furnaces. Soot warms the upper air by absorbing sunlight and artificially cools the earth's surface. This can cause regional droughts due to less evaporation from the cooler ocean.

Source: John J. Fialka, "Discovery of 'Asian Brown Cloud' Over Indian Ocean Sets Off Fight," Wall Street Journal, May 6, 2003.

[John Lenin]

And if you believe this article as fact you probalbly believe the quotes below.

The continued rapid cooling of the earth since WWII is in accord with the increase in global air pollution associated with industrialization, mechanization, urbanization and exploding population. -- Reid Bryson, "Global Ecology; Readings towards a rational strategy for Man", (1971)

The battle to feed humanity is over. In the 1970s, the world will undergo famines. Hundreds of millions of people are going to starve to death in spite of any crash programs embarked upon now. Population control is the only answer -- Paul Ehrlich - The Population Bomb (1968)

I would take even money that England will not exist in the year 2000 -- Paul Ehrlich in (1969)

In ten years all important animal life in the sea will be extinct. Large areas of coastline will have to be evacuated because of the stench of dead fish. -- Paul Ehrlich, Earth Day (1970)

Before 1985, mankind will enter a genuine age of scarcity . . . in which the accessible supplies of many key minerals will be facing depletion -- Paul Ehrlich in (1976)

This [cooling] trend will reduce agricultural productivity for the rest of the century -- Peter Gwynne, Newsweek 1976

There are ominous signs that the earth's weather patterns have begun to change dramatically and that these changes may portend a drastic decline in food production - with serious political implications for just about every nation on earth. The drop in food production could begin quite soon... The evidence in support of these predictions has now begun to accumulate so massively that meteorologist are hard-pressed to keep up with it. -- Newsweek, April 28, (1975)

This cooling has already killed hundreds of thousands of people. If it continues and no strong action is taken, it will cause world famine, world chaos and world war, and this could all come about before the year 2000. -- Lowell Ponte "The Cooling", 1976

If present trends continue, the world will be about four degrees colder for the global mean temperature in 1990, but eleven degrees colder by the year 2000...This is about twice what it would take to put us in an ice age. -- Kenneth E.F. Watt on air pollution and global cooling, Earth Day (1970)

[green team 1999]

"Then why did global temps DROP after the eruption of Mt. Pinatubo? Sometimes dese guys just don't make sense...

Mt. Pinatubo created a ring of dark matter around the world for a period of time,the sun rays and heat blocked from reaching in,think of it as a mini-nuclear winter.
smog and soot let the heat from the sun come in but don`t let it out.warming the planet.