IN THE US, it seems, it is inappropriate for scientists on the federal payroll to talk about the dangers of climate change. Ask Jim Hansen, director of NASA’s Goddard Institute for Space Studies and George W. Bush’s top climate modeller. In December 2005, he told a meeting of the American Geophysical Union that the Earth’s climate “is nearing a tipping point”. This week a report by the UK government makes a similar analysis (“Icy warning”). Yet NASA has been trying to shut Hansen up.
Strictly speaking, this gagging order is not new. Just before the last presidential election in…
