Some natural events, like big volcanic eruptions that spit huge amounts of dust and chemicals into the upper atmosphere, could temporarily lower the Earth’s temperature. Trying to replicate that kind of event is a risky business say researchers from the EU-funded IMPLICC project. Here is a striking view of Sarychev volcano (Russia’s Kuril Islands, northeast of Japan) at an early stage of eruption on 12 June 2009 as seen by the astronauts on board the International Space Station. © NASA