From Bob Ward, Grantham Research Institute on Climate Change and the Environment
It is great to see US president Barack Obama showing leadership on climate change (newscientist.com/article/dn23758). But without the support of Congress for new federal legislation, he is fighting with one hand tied behind his back.
The latest figures show that greenhouse gas emissions in the US in 2011 were 6.9 per cent below 2005 levels, compared with Obama’s target of 17 per cent by 2020. But they are still more than 8 per cent above 1990 levels, the international baseline.
Moreover, this means Americans emit more than 20 tonnes of greenhouse gases per person each year. If the world is to have a reasonable chance of avoiding dangerous global warming of more than 2 °C, emissions will have to average no more than 2 tonnes per person by 2050. I hope Obama will take the argument to the American people and challenge the Republican party, which is in a state of denial about climate change.
London, UK
