Global warming pause linked to sulfur in China
Scientists have come up with a possible explanation for why the rise in Earth’s temperature paused for a bit during the 2000s, one of the hottest decades on record.
The answer seems counterintuitive. It’s all that sulfur pollution in the air from China’s massive coal-burning, according to a new study.
Sulfur particles in the air deflect the sun’s rays and can temporarily cool things down a bit. That can happen even as coal-burning produces the carbon dioxide that contributes to global warming.
« People normally just focus on the warming effect of CO2 (carbon dioxide), but during the Chinese economic expansion there was a huge increase in sulfur emissions, » which have a cooling effect, explained Robert K. Kaufmann of Boston University. He’s the lead author of the study published Monday in Proceedings of the National Academy of Science.
Chinese coal consumption doubled between 2003 and 2007, and that caused a 26 percent increase in global coal consumption, Kaufmann said.
Sulfur’s ability to cool things down has led some to suggest using it in a geoengineering feat to cool the planet. The idea is that injecting sulfur compounds very high into the atmosphere might help ease global warming by increasing clouds and haze that would reflect sunlight. Some research has concluded that’s a bad idea.