Research has cast new doubt on the wisdom of using Sun-blocking sulphate particles to cool the planet.

- 26 / 04 / 2008 13:58

Sulphate injections are one of several "geo-engineering" solutions to climate change being discussed by scientists.

But data published in Science journal suggests the strategy would lead to drastic thinning of the ozone layer.

This would delay the recovery of the Antarctic ozone hole by decades, and cause significant ozone loss over the Arctic, say US researchers.

The idea of pumping sulphur into the upper atmosphere ito counteract global warming comes from nature.

Major volcanic eruptions emit vast quantities of sulphur particles that can cool the planet significantly.

This was observed following the 1991 eruption of Mount Pinatubo.

But one potential drawback is that sulphates provide a surface on which chlorine gases in polar clouds can become activated, causing chemical reactions that lead to the destruction of ozone molecules.