Climate scientists are on the defensive after damaging emails were leaked in a bid to discredit evidence of global warming ahead of the Durban summit.

Scientists at a top British climate research unit embroiled in a row over their work were cleared of dishonesty by an independent probe on Wednesday.

Regular swearing at work can help boost team spirit among staff, allowing them to express better their feelings as well as develop social relationships, according to a study by British researchers. They assessed that swearing will become more common as traditional taboos are broken down.

In a new book called Cool It, the global-warming sceptic Bjorn Lomborg has sparked fresh debate about the dangers of increasing temperatures with new claims that polar bears are not on the brink of collapse and are more threatened by hunting than by climate change.