AdvertisementScientists Debate Shading Earth As Climate FixJune 16, 2009Richard HarrisfacebookEmailVolcanic eruptions, like this blast from Mount Pinatubo in the Philippines in 1991, send sulfate particles into the air. These particles reflect part of the sun's radiation and have a cooling effect on the Earth. Scientists are debating whether spraying tiny particles into the stratosphere could help combat climate change. (USGS)