Humans ‘causing stronger storms’
11/9/2006 BBC In July last year, Kerry Emanuel, from the Massachusetts Institute of Technology, published research showing that the duration, maximum wind speeds and energy released in tropical storms has increased markedly in both the North Atlantic and the North Pacific oceans since the mid-1970s. A few months later, Peter Webster from the Georgia Institute of Technology documented a rise in the incidence of category 4 and 5 storms; the 15-year period from 1975 to 1989 saw 171 severe hurricanes, but the number rose to 269 for the subsequent 15 years. He told the BBC News website at the time: “What I think we can say is that the increase in intensity is probably accounted for by the increase in sea-surface temperature, and I think probably the sea-surface temperature increase is a manifestation of global warming.”