Attempts have been made to break into the offices of one of Canada’s leading climate scientists, it was revealed yesterday. The victim was Andrew Weaver, a University of Victoria scientist and a key contributor to the work of the Inter-governmental Panel on Climate Change (IPCC). In one incident, an old computer was stolen and papers were disturbed.

In addition, individuals have attempted to impersonate technicians in a bid to access data from his office, said Weaver. The attempted breaches, on top of the hacking of files from British climate researcher Phil Jones, have heightened fears that climate-change deniers are mounting a campaign to discredit the work of leading meteorologists before the start of the Copenhagen climate summit tomorrow.

“The key thing is to try to find anybody who’s involved in any aspect of the IPCC and find something that you can … take out of context,” said Weaver. The prospect of more break-ins and hacking has forced researchers to step up computer security.

‘We don’t have a leader who is able to grasp [the issue] and say what is really needed. Instead we are trying to continue business as usual,’ say James Hansen. Photograph: Gareth Fuller/PA

The scientist who convinced the world to take notice of the looming danger of global warming says it would be better for the planet and for future generations if next week’s Copenhagen climate change summit ended in collapse.

In an interview with the Guardian, James Hansen, the world’s pre-eminent climate scientist, said any agreement likely to emerge from the negotiations would be so deeply flawed that it would be better to start again from scratch.

“I would rather it not happen if people accept that as being the right track because it’s a disaster track,” said Hansen, who heads the Nasa Goddard Institute for Space Studies in New York.