A new study has almost ruined hopes that global warming could be countered by releasing certain chemicals into the atmosphere. It was previously thought that sulfur compounds have the ability of cooling down the earth by blocking sun rays. The effect was first observed after volcanic eruptions.

However, experts have found that potentially worse consequences are associated with sulfates. The most prominent is that it destroys the ozone layer, which means that the ongoing recovery of the hole in the ozone layer above Antarctica will be delayed by decades.

This happens because sulfates released at an altitude of some 6 to 30 miles high would activate chlorine gases found in the cold layers of the stratosphere above the two Poles, which in turn reacts with the ozone molecules effectively decomposing them.

The research, by Simone Tilmes of the National Center for Atmospheric Research (NCAR) in Boulder, Colo., was published in the journal Science Express. "The challenges of global warming mitigation are extremely complex," said Cliff Jacobs, program director in NSF's Division of Atmospheric Sciences. The National Science Foundation (NSF), is NCAR's principal sponsor.

"Continued investment in basic research will allow the most cost-effective solutions--and those of the most benefit to society--to be found," Jacobs said.

Ozone is made up of three oxygen atoms, instead of two found in the normal oxygen molecule. This means that ozone is much less stable and therefore it reacts easily with various substances, turning into normal oxygen molecules. It was discovered by Christian Friedrich Schönbein in 1840, who named it after the Greek word for smell. Schönbein noticed the specific smell which comes with lightning storms. Ozone shields the earth from high-energy UV radiation coming from the Sun.