US plans sun-reflection experiment

Scientists in the United States are to spray tiny amounts of sulphate particles into the atmosphere in an attempt to reflect the sun and cool the planet.

The project is the latest in a growing number of technological interventions or geoengineering experiments to manipulate the earth’s climate and tackle global warming.

Environmental opponents, such as the Canada-based ETC group, argue geoengineering experiments do nothing to solve the cause of climate change and are a distraction from the need to drastically reduce greenhouse-gas emissions. There are also concerns that there is not yet any mechanism to regulate and control such experiments.

A field test by UK scientists to pump minute chemical particles into the upper atmosphere to reflect sunlight and cool the planet were scrapped in May this year, in part, because of concerns about the lack of rules governing such experiments.

At the UN biodiversity summit in Japan in 2010, countries agreed to take a “precautionary approach” to geo-engineering and other large-scale human interventions to alter the Earth’s climate, which may impact. This, however, does not apply to the United States, which has not ratified the UN agreement.