Something you'd expect from The Onion...

Scientists say pollution may combat global warming

Updated Thu. Nov. 16 2006 2:49 PM ET

Associated Press

NAIROBI, Kenya -- If the sun warms the Earth too dangerously, the time may come to draw the shade. The "shade" would be a layer of pollution deliberately spewed into the atmosphere to help cool the planet. This over-the-top idea comes from prominent scientists, among them a Nobel laureate.

The reaction here at the UN conference on climate change is a mix of caution, curiosity and some resignation to such "massive and drastic" operations, as the chief UN climatologist describes them.

The Nobel Prize-winning scientist who first made the proposal is himself "not enthusiastic about it.".....

The Dutch climatologist, awarded a 1995 Nobel in chemistry for his work uncovering the threat to Earth's atmospheric ozone layer, suggested that balloons bearing heavy guns be used to carry sulfates high aloft and fire them into the stratosphere.

While carbon dioxide keeps heat from escaping Earth, substances such as sulfur dioxide, a common air pollutant, reflect solar radiation, helping cool the planet.

Tom Wigley, a senior U.S. government climatologist, followed Crutzen's article with a paper of his own on Oct. 20 in the leading U.S. journal Science. Like Crutzen, Wigley cited the precedent of the huge volcanic eruption of Mount Pinatubo in the Philippines in 1991.

Pinatubo shot so much sulfurous debris into the stratosphere that it is believed it cooled the Earth by .9 degrees for about a year....

A massive dissemination of pollutants would be needed every year or two, as the sulfates precipitate from the atmosphere in acid rain.

Wigley said a temporary shield would give political leaders more time to reduce human dependence on fossil fuels -- the main source of greenhouse gases. He said experts must more closely study the feasibility of the idea and its possible effects on stratospheric chemistry.

Nairobi conference participants agreed.

"Yes, by all means, do all the research," Indian climatologist Rajendra K. Pachauri, chairman of the 2,000-scientist UN network on climate change, told The Associated Press.

But "if human beings take it upon themselves to carry out something as massive and drastic as this, we need to be absolutely sure there are no side effects," Pachauri said...