The majority of the British public is still not convinced that climate change is caused by humans - and many others believe scientists are exaggerating the problem, according to an exclusive poll for The Observer. The results have shocked campaigners who hoped that doubts would have been silenced by a report last year by more than 2,500 scientists for the UN Intergovernmental Panel on Climate Change (IPCC), which found a 90 per cent chance that humans were the main cause of climate change and warned that drastic action was needed to cut greenhouse gas emissions. The findings come just before...