Deep cuts in carbon dioxide emissions are urgently needed to prevent dangerous climate change, but they must be complemented by reductions in short-lived climate pollutants (SLCPs), which produce a strong global warming effect but have relatively brief atmospheric lifetimes (figure). SLCPs generally cause more radiative forcing per kg than carbon dioxide, and their mitigation could have a greater effect on climate change in the near term (in some cases almost immediately)—eg, by reducing the melting of snow and ice.