SaDLY, once again Nigel Lawson has muddied the waters with respect to our understanding of climate change ("Listen up, BBC, the climate debate is far from over", News Review, last week). He incorrectly states that "there has been no recorded global warming at all so far this century". The facts are that the observed warming in the 2000s has been relatively slow - between 0.05C and 0.13C, compared with a long-term trend of 0.16C per decade since the late 1970s - and that last year was the second-warmest on record, according to the Met Office.  Lawson quotes William Happer, who contends that the Earth's climate will warm by only about 1C over 200 years, and that the positive effects outweigh the negative effects.  The vast majority of climate scientists would strongly