Natural "heat Vent" In Pacific Cloud Cover

Press Release:
Goddard Space Flight Center, Greenbelt, Md. February 28, 2001


American Meteorological Society


Release No: 01-18

NATURAL "HEAT VENT" IN PACIFIC CLOUD COVER
COULD DIMINISH GREENHOUSE WARMING

The tropical Pacific Ocean may be able to open a "vent" in its
heat-trapping cirrus cloud cover and release enough energy into space
to significantly diminish the projected climate warming caused by a
buildup of greenhouse gases in the atmosphere.

If confirmed by further research, this newly discovered effect -
which is not seen in current climate prediction models - could
significantly reduce estimates of future climate warming. Scientists
from NASA's Goddard Space Flight Center in Greenbelt, Md., and the
Massachusetts Institute of Technology present their findings in the
March 2001 issue of the Bulletin of the American Meteorological
Society.

"High clouds over the western tropical Pacific Ocean seem to
systematically decrease when sea surface temperatures are higher,"
says Arthur Y. Hou of Goddard's Data Assimilation Office. Hou and
co-authors Ming-Dah Chou of Goddard's Climate and Radiation Branch
and Richard S. Lindzen of MIT analyzed satellite observations over
the vast ocean region, which stretches from Australia and Japan
nearly to the Hawaiian Islands.

The researchers compare this inverse relationship to the eye's iris,
which opens and closes to counter changes in light intensity. The
"adaptive infrared iris" of cirrus clouds opens and closes to permit
the release of infrared energy, thus resisting warmer tropical sea
surface temperatures, which occur naturally and are predicted to
increase as the result of climate warming.

The study compares detailed daily observations of cloud cover from
Japan's GMS-5 Geostationary Meteorological Satellite with sea surface
temperature data from the U. S. National Weather Service's National
Centers for Environmental Prediction over a 20-month period (January
1998 to August 1999). The researchers found that cumulus cloud towers
produced less cirrus clouds when they moved over warmer ocean
regions. For each degree Celsius rise in ocean surface temperature,
the ratio of cirrus cloud area to cumulus cloud area over the ocean
dropped 17-27 percent. The observed range of surface temperatures
beneath the clouds varied by 6.3 degrees Fahrenheit (3.5 degees C).

The authors propose that higher ocean surface temperatures directly
cause the decline in cirrus clouds by changing the dynamics of cloud
formation and rainfall. Cirrus clouds - high-altitude clouds of ice
crystals - typically form as a byproduct of the life cycle of cumulus
towers created by rising updrafts of heated, moist air. As these
cumulus convective clouds grow taller, cloud water droplets collide
and combine into raindrops and fall out of the cloud or continue to
rise until they freeze into ice crystals and form cirrus clouds.

"With warmer sea surface temperatures beneath the cloud, the
coalescence process that produces precipitation becomes more
efficient," explains Lindzen. "More of the cloud droplets form
raindrops and fewer are left in the cloud to form ice crystals. As a
result, the area of cirrus cloud is reduced."

Clouds play a critical and complicated role in regulating the
temperature of the Earth. Thick, bright, watery clouds like cumulus
shield the atmosphere from incoming solar radiation by reflecting
much of it back into space. Thin, icy cirrus clouds are poor
sunshields but very efficient insulators that trap energy rising from
the Earth's warmed surface. A decrease in cirrus cloud area would
have a cooling effect by allowing more heat energy, or infrared
radiation, to leave the planet.

If this "iris effect" is found to be a general process active in
tropical oceans around the world, the Earth may be much less
sensitive to the warming effects of such influences as rising
greenhouse gas concentrations in the atmosphere. The researchers
estimate that this effect could cut by two-thirds the projected
increase in global temperatures initiated by a doubling of carbon
dioxide in the atmosphere.

The American Meteorological Society is the nation's leading
professional society for scientists in the atmospheric, oceanic, and
related sciences.


-end-

 

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Temper tantrums

And so it maybe that the world’s temperature isn’t rising at all but in fact maintaining it’s normal balance. Those normal balances change from year to year (which makes it harder to identify temp changes as starting a new trend) and have to be averaged out.
And even though we help put lot’s of green house gases and ozone destroyers it is nowhere near what nature does and is capable of. Volcanoes dump tremendous amounts of chemicals, co2, sulfur compounds, and dust into the air. Some so intense that the effects circle the globe several times over. In the 1800’s was the year without a summer, when the dust from a volcano blocked the sun for a few years. We simply do not match the output of a volcano that has blown it’s lid off.

 

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Re: Temper tantrums

I'm not entirely clear on what you're saying here; are you suggesting that we aren't affecting the climate? If you aren't, I apologise; if you are, you're wrong.
You seem to be saying that we dont' match nature for noxious emissions; in that you're correct. But just because it's natural it isn't necessarily good. I wouldn't suggest that planting bombs is okay just because earthquakes are capable of causing vastly more damage.
Also: we can't match a volcano for CO2 emissions in any one year. But compare the total amount of CO2 put out by any volcano over the last two hundred years to our emissions over the same period, and you'll see a greater degree of corelation.

 

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Temp Check

No, I am not saying that we don’t affect the temperature of the world. What I am saying is that it may not be as much as thought. I used the example of the volcano to show that there are other contributors beside our pollution rate or level of activity. Even the lowly termite contributes to the problem.
Anyway, in the news a few weeks ago was the item that the computer models being used to predict the behavior of pollution and its results were off. That one of the presumptions that the model used as a base was not correct. This resulted in giving a false temperature reading for the average that erred towards a warmer than normal reading. It does go to show that we are still grasping to understand the total concept in laboratory of reality.

 

Re: Temp Check

There's no question that we're far from an accurate model of the climate; I doubt we'll ever have one that can be relied on with any degree of certainty. However, as more and more data from more and more studies come in, it becomes more apparent that 1. we're having and effect and 2. this effect is bad.
You're right; even without humans, vast swathes of CO2 would be placed in the atmosphere. But two human activities - deforestation and fossil fuel burning - are having dramatic and adverse effects on the planet. I don't want to go into more detail as I can't cite specific studies, but I'm sure you're capable of using google or bottomquark.

 

Nothing like an idiot statement to start things off again. In actuality, yes, I do believe that we have had a severe impact upon our environment. The slash and burn techniques that have been employed are wasteful in that the soil that remains after the burn is not a quality soil that will last. As no rotation of crops are practiced it “wears out” rather quickly requiring more of the same to have a new field capable of producing crops every few years. The burning of acres and acres of trees give off pollutants that carry far beyond the area of the burn adding to the problem. Further the trees burnt will take years and years to come back to their original state. Many of which are directly responcible for the filtering out of said pollutants.
Fossil fuel burning…
The combustion of fossil fuel gives off pollutants that cause smog. Smog is dangerous over the long haul to all living animals. At least the lead was taken out. The effects of lead will be with us for a long time to come. The Roman civilization is suspected of having to deal with lead contamination and poisoning from using lead for their pipes carrying drinking water. Studies have shown that our children and the adults have had steady building amounts of lead in the blood stream. It may well be possible that a lot of our hostilities in society are derived from the lead poisoning. If so it will take a few generations to get rid of the influence of this lead. Another effect is that lead poisoning will lower the mental capacity. At a time when we are expanding knowledge I would hazard a guess that some researcher will wonder why none ever thought of some theorem or experiment to try to verify this or that idea. While not having used the search engines to look this info up, it would probably behoove me to do so. and thanx for the suggestion.

 

Isn't it wonderful?

Hey rde, aren't you lucky that thanks to mad cow disease and hoof and mouth disease a whole lot of the methane emitting livestock in you area of the planet are being eliminated.

If I'm not mistaken, only the termites emit more methane than flatulant cows.

 

I guess we'll start seeing a torch party someday as the in thing!

 

I'll go for it, Wet1 - So long as it's SUV's that are getting tourched.

 

Re: Isn't it wonderful?

I've got patience. It's only a matter of time before F&M crosses the atlantic, and we see cattle being slaughtered by the thousand. Wonder who the ranchers'll sue this time?

And as a dedicated urbanite, I haven't seen a single funeral pyre. I suppose I could climb Bray Head, which might (weather permitting) give me a view of columns of Welsh smoke, but it's hard to muster any degree of schadenfreud when the English or Americans aren't involved.