And go get yourself some cheap sunglasses.............
Posted on 05/27/2004 12:37:28 PM PDT by FourPeas
WASHINGTON (AP) — Scientists studying earthshine — the amount of light reflected by the Earth — say the planet appeared to dim from 1984 to 2001 and then reversed its trend and brightened from 2001 to 2003.
The shift appears to have resulted from changes in the amount of clouds covering the planet. More clouds reflect more light back into space, potentially cooling the planet, while a dimmer planet with fewer clouds would be warmed by the arriving sunlight.
That means the changes in brightness could signal climate change, though it's too early to tell.
Steven Koonin, a California Institute of Technology physicist and co-author of the paper, said that "at the moment, the cause of these variations is not known, but they imply large shifts in the Earth's radiative budget. Continuing observations ... will be necessary to learn their implications for climate."
"This work is probably going to be used in arguments for and against global warming. Our paper neither proves or disproves the carbon dioxide effect," said Enric Palle, lead author of the report appearing in Thursday's issue of the journal Science.
"Our results are only part of the story, since the Earth's surface temperature is determined by a balance between sunlight that warms the planet and heat radiated back into space, which cools the planet," said Palle, of the Big Bear Solar Observatory in California, operated by the New Jersey Institute of Technology.
Climate change "depends upon many factors in addition to (reflected light), such as the amount of greenhouse gases present in the atmosphere. But these new data emphasize that clouds must be properly accounted for and illustrate that we still lack the detailed understanding of our climate system necessary to model future changes with confidence."
The researchers used two sets of records to establish the amount of light reflected from the Earth.
The records, which partly overlap, include measurements of cloud cover taken by satellites and an analysis of earthshine, which was determined by studying how much it illuminates the dark portion of the moon.
But the use of two separate types of measurements gave pause to James A. Coakley Jr. of Oregon State University, who studies climate change and satellite cloud data.
Observations of "sunlight reflected by the Earth are far from being well understood. At this stage, it's too early to tell how useful such observations might be as a measure of climate variability and climate change," said Coakley, who was not part of the research team.
Philip R. Goode of the New Jersey institute, a co-author of the paper, contended that the moon analysis is in fact quite accurate.
"Our method has the advantage of being very precise because the bright lunar crescent serves as a standard against which to monitor earthshine, and light reflected by large portions of Earth can be observed simultaneously," said Goode.
Earthshine brightening the face of the moon, he noted, was first described by Leonardo da Vinci.
Regular earthshine observations began in 1997, and the researchers suggested that the changes they observed may be part of a natural variation. Continuing the observations through an entire 11-year cycle of solar variability will be important to better understand the changes, they said.
The research was funded by the National Aeronautics and Space Administration.
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On the Net:
Science: http://www.sciencemag.org
Science ping.
This is series.
And go get yourself some cheap sunglasses.............
The head spins.
Gee - they try to make assumptions over a few-year observation - I guess "science" is moving into the fast lane...
Geez, ya think?
Of course Al Gore is far smarter than any of these climate scientists. That's why he's absolutely certain about future weather patterns.
Science list ping.
So if we are reflecting more sun light, we should be experiencing global cooling?
I have come to the conclusion that all climate speculation results in no more useful information than navel gazing.
I thought they were saying that more clouds created a greenhouse effect, radiating heat back onto the surface, warming the planet.
I'm so confused...
-PJ
That lines up pretty well to our local climate. We finally got some oldtime cold this winter, not a lot, just some, a few days of 40 below. 20 years ago we got 40 below frequently. There was one year when 40 below was the warmest it got all month.
Just a few weeks ago those moronic tree huggers had invented "global dimming", and they properly got hammered with ridicule. Are they trying to backpedal now?
Leftists are heads at a tennis match. Their beliefs go this way and that way, this way and that way....
Still ROTFLMAO!!!!!!
This just happens to track almost exactly the Earth's CFC pollution. Remember, the "styrofoam killing the ozone layer" stuff? It was outlawed in the Montreal Protocols or something. Everybody supported it, across the board.
Maybe, just maybe, it is not a coinkydink. Maybe CFC production had something to do with this "brightening."
Either that or Turtle Wax.
This could be a vindication for Frederick Seitz, former NAS president and dissenting member of the IPCC--he has theorized for years that the planet could compensate for rising atmospheric temperature by producing more high altitude clouds.
http://www.fact-index.com/f/fr/frederick_seitz.html
I knew a bookie once that did the same thing with his records.
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