In fact – while most sources now list soot as the second most important cause of global warming – it may even be in first place. As the Christian Science Monitor reports: "Given the uncertainties in the estimates, black-carbon soot may even outpace CO2's warming effect, according to the 232-page study published today in the Journal of Geophysical Research–Atmospheres."
Indeed, the ability of soot to melt snow and ice is so well-known that, in the 1970s, scientists – including Obama's top science adviser, John Holdren– proposed pouring soot over the arctic to melt the ice and so prevent the ice age which scientists feared.
Read more at: http://m.csmonitor.com/Environment/2013/0115/Soot-is-No.-2-global-warming-culprit-study-finds-video