I found this to be the most interesting point:

"However, the study did not tackle the question of whether Earth's surface temperature is actually increasing. In fact, whether this greenhouse effect will lead to global warming or global cooling is unclear, the study scientists said."

http://www.cnn.com/2001/TECH/science/03/14/greenhouse.gases.02/index.html

Report: Satellite data proves greenhouse effect

March 14, 2001 Web posted at: 3:39 p.m. EST (2039 GMT)

In this story:

Political debate heats up

Clouds obscure the future

RELATED STORIES, SITES

LONDON, England (CNN) -- Satellite data has provided the first "direct observational evidence" that the greenhouse effect is producing long-term changes in the Earth's atmosphere, scientists said Wednesday.

Comparing satellite observations from 1970 and 1997, British researchers said accumulating greenhouse gases have limited the amount of infrared radiation escaping into space.

An Imperial College of London team looked at readings of infrared light from the Earth's surface, specifically in the wavelengths absorbed by greenhouse gases such as carbon dioxide, methane and ozone.

"We're absolutely sure, there's no ambiguity: This shows the greenhouse effect is operating and what we are seeing can only be due to the increase in the gases," said lead investigator John Harries of London's Imperial College.

Evidence was also found of smaller increases in chlorofluorocarbons, refrigerants blamed for destroying the ozone layer that protects Earth from ultraviolet radiation.

The study was reported in Thursday's issue of the journal Nature.

Political debate heats up

Atmospheric scientists not involved in the study said the satellite data provide concrete confirmation that greenhouse gases are building up.

The findings come as the political debate intensifies over whether global warming is a real danger.

A report released in January in China by an international panel predicted global temperatures could rise as much as 5.8 degrees Celsius (10.5 degrees Fahrenheit) over the next century, primarily because of pollution.

U.S. and European environmental officials, however, have not been able to agree on how to implement the 1997 Kyoto Protocol, which calls for reductions in greenhouse-gas emissions.

On Tuesday, President Bush backed away from a campaign pledge to restrict carbon dioxide from coal-burning power plants, saying mandatory controls would lead to higher electricity prices.

The decision angered environmentalists, who for years have pushed for reduced carbon dioxide emissions from U.S. power plants.

Clouds obscure the future

However, the study did not tackle the question of whether Earth's surface temperature is actually increasing. In fact, whether this greenhouse effect will lead to global warming or global cooling is unclear, the study scientists said.

The greenhouse effect could start a cycle in which more clouds are formed, stopping the sun's energy from reaching Earth's surface in the first place, Harries said.

"The effect of clouds on the planet is very complex, and frankly we don't understand it," Harries said.

In the British study, the researchers compared data from the Japanese ADEOS satellite, which produced about nine months of data starting in 1996, and NASA's Nimbus 4 satellite between April 1970 and January 1971. Only clear-sky readings of the atmosphere over the central Pacific were compared.

Drew Shindell, an atmospheric physicist at NASA's Goddard Institute for Space Studies in New York, said the research should end the debate over the greenhouse effect, but not over how to address the problem.

"One of the main things that cause people to be skeptical of global warming is the lack of that real, definite connection between greenhouse gases and the planet getting warmer," Shindell said. "This really gives concrete evidence for the first time that greenhouse gases are changing the energy balance of the planet."

Scientists will have more opportunities to compare infrared data following the launch later this year of a new NASA satellite carrying the first of the next generation of infrared instruments.

Environmental Correspondent Natalie Pawelski and The Associated Press contributed to this report.

-- Buddy (buddydc@go.com), March 14, 2001

Answers

And to complicate matters this is also from Nature:

A natural heat-vent in the clouds over the Pacific ocean, may enable the Earth to keep its cool despite a rise in the amount of greenhouse gas in the atmosphere, new research from a leading 'greenhouse sceptic', suggests1.

Although more work will be needed to establish the extent of the vent's suggested 'thermostatic cooling' effect, the finding challenges meteorologists to account for clouds in future global climate models.

Richard Lindzen, a meteorologist at the Massachusetts Institute of Technology in Cambridge and colleagues at NASA's Goddard Space Flight Center in Greenbelt, Maryland used satellite measurements of sea surface temperature and cloud cover over the equatorial Pacific Ocean from Australia to the Hawaiian Islands.

They found that when sea surface is warmer — and therefore so too is the atmosphere above the sea — the production of cirrus clouds slows down. Made up of ice crystals which don't reflect incoming sunlight well, cirrus clouds trap heat leaving the Earth beneath them.

"The area [of cirrus] per unit cumulus, went down rather strikingly with temperature," Lindzen says. Thick, fluffy cumulus clouds act like giant parasols, reflecting the Sun's rays back into space.

It is this decrease in insulating cirrus cloud in response to an increase in sea surface temperature that could act as a thermostatic cooling mechanism says Lindzen. Current global climate models don't include the role of cirrus and cumulus clouds so thier predictions on global warming may be highly exaggerated, he believes.

Depending on which model is used, the best estimate is a rise in global temperature of between 1.5ºC to 4.5ºC if levels of CO2 double from today's levels. Lindzen's pacific heat-vent model "would knock it down to a half a degree or maybe one-point something", he says.

Lindzen admits that more data will be needed before the potential effect of the system can be verified, but because cumulus clouds occur world-wide, he's confident that the heat vent is widespread.

According to Tony Slingo, at the Hadley Centre for Climate Prediction and Research in Bracknell, Britain, climate modellers are used to hearing a differing opinion from Lindzen who he describes as one of the few qualified meteorologists who regularly challenges the 'greenhouse' model of global warming.

But Slingo says they're not ready to ditch their models just yet.

"The gauntlet has been thrown down," says Slingo, who looks forward to Lindzen and other researchers expanding the search for the heat vent observed in the pacific to other areas of the globe. "They're challenging some of the basic ideas and methods in our climate models, " says Slingo. "Lets get global data and examine this on a global scale."

-- The Engineer (spcengineer@yahoo.com), March 14, 2001.

On Tuesday, President Bush backed away from a campaign pledge to restrict carbon dioxide from coal-burning power plants, saying mandatory controls would lead to higher electricity prices.

And so it begins. Honor and integrity in the white house-yeah right-backed down on a campaign pledge already. Same old shit, different party.

-- FutureShock (gray@matter.think), March 14, 2001.

Future Shock,

Have you lost your mind. You are starting to sound like Joseph Farrah, Michael Savage, or Rush Limbaugh. Only the Republicans can do wrong. You are just a right-winger waiting to happen.

-- beware (it@might.happen), March 14, 2001.

A lot of people seem to have an opinion on this matter. One question: how many of you have just read the press accounts and how many have actually read the papers. It makes a difference.

Best Wishes,,,,,

Z

-- Z1X4Y7 (Z1X4Y7@aol.com), March 14, 2001.

Actual papers about the current debate no, Z I havn't. About earth's cycling through climatic change...yeah. Keeping the jury out on this one doesn't change the cyclical nature of warm vs cold. Acceleration of either leads to a quicker extinction of whomever happens to be around now but doesn't change the inevitable. Recommend once again the book Rare Earth.

What really pisses is that be it glacial or hot house the survivors needed to build after the next lap of biological progress won't have a store of fossil fuel to work with.

-- Carlos (riffraff@cybertime.net), March 15, 2001.