Agence France Presse: Nicholas Stern, the author of a key climate change report, said in an interview published Thursday that he and his team "underestimated" the risks of global warming. Speaking to the Financial Times, former World Bank chief economist Stern also defended the conclusions in his 2006 report, which has been criticised by some economists and climate change sceptics, including former British finance minister Lord Nigel Lawson. Stern’s 700-page report estimated the effects of …