Research into global warming defended

In a letter published in the journal Science, more than 250 members of the United States National Academy of Sciences, including 11 Nobel Prize laureates, condemned the increase in "political assaults" on scientists – in particular climate researchers.

They demanded an end to harassment of scientists by politicians and to the "outright lies" being spread about them.

They also called for an end to "McCarthy-like threats of criminal prosecution against our colleagues based on innuendo and guilt by association".

The statement follows mistakes uncovered in the Intergovernmental Panel on Climate Change's most recent assessment of climate change science, published in 2007.

It also comes in the wake of the row over leaked emails from the University of East Anglia's Climatic Research Unit which climate sceptics claimed showed researchers were manipulating data to back up the theory of man-made global warming.

The letter from the 255 leading scientists from 53 disciplines said there was "nothing remotely identified in the recent events that changes the fundamental conclusions about climate change".

The scientists likened climate change science to the theories of evolution, the Big Bang and that the Earth is around 4.5 billion years old, which are "overwhelmingly" accepted by scientists, despite the objections of some people.

"There is compelling, comprehensive and consistent objective evidence that humans are changing the climate in ways that threaten our societies and the ecosystems on which we depend," they said and added that attacks on climate science and scientists by climate-change deniers "are typically driven by special interests or dogma".