Photograph from media.treehugger.com
James Hansen was in the UK this week to receive the prestigious Edinburgh Medal for his contribution to science. In his lecture he argued that taking action on climate change is on a par with ending slavery. Hansen was one of the first scientists to study the effects of climate change and in 1981 he wrote a paper in Science which has recently been evaluated in RealClimate and found he underestimated global warming by 30%. In a soon to be published paper he argues for a global levy on fossil fuels to save the planet from extreme weather events.