Methane is a greenhouse gas 25 times more potent than carbon dioxide, so when it’s leaking by the ton, it’s a $50 billion problem. The New York Times described the phenomenon of methane leakage in a recent article which raised questions about the true costs of this waste.

Details from a map showing the impact of a global temperature rise of 4C. Photograph: Met Office

The British government today raised the political stakes on climate change when it published a new map of the world that details the likely effects of a failure to cut greenhouse gas emissions.

Europe is a laggard when it comes to responding to the threat of climate change. Photograph: Phil Noble/Reuters

The environment council meeting in Brussels yesterday agreed the targets that Europe will put forward in international negotiations in Copenhagen. In an effort to convey some kind of leadership they agreed to increase the long-term reduction target in 2050 – my, how brave – but failed to make any new offer in relation to the more important 2020 target.

Remanonjona Feroce founded the village of Anjamahavelo – meaning At the Lucky Baobab – in Madagascar a generation ago. With memories of a flood still fresh, he chose a spot far from the nearest river. He cleared the wild forest and sacrificed a sheep in the hope that it would make the owls, lemurs and snakes go away.

“Animals can’t live together with little children and young girls,” explained Feroce, an 85-year-old great-grandfather. “They don’t want snakes to be here because they have bad spirits. They strangle children by curling around the neck. Owls are bad birds. If one hoots, it means somebody will die.”

The UN climate change treaty, signed in 1992, committed the world to avoiding “dangerous anthropogenic interference with the climate system”. Yet, since that time, greenhouse gas emissions have continued to soar.

The US has proved to be the biggest laggard in the world, refusing to sign the 1997 Kyoto protocol or to adopt any effective domestic emissions controls. As we head into the global summit in Copenhagen in December to negotiate a successor to the Kyoto protocol, the US is once again the focus of concern. Even now, American politics remains strongly divided over climate change – though President Barack Obama has new opportunities to break the logjam.

Gordon Brown today warned that the world is on the brink of a “catastrophic” future of killer heatwaves, floods and droughts unless governments speed up negotiations on climate change before vital talks in Copenhagen in December.

This applies to the US as much as anyone, he said, adding that “there is no plan B”, and that agreement cannot be deferred beyond the UN-sponsored Copenhagen conference.

There are fears that Barack Obama does not have the political capital to reach a deal in Copenhagen and will instead use a visit to China next month to reach a bilateral deal that circumvents the UN.

Downing Street is also concerned that there is no agreement on how to finance a climate change package in developing countries.

The prime minister delivered his warning to a meeting of environment ministers brought together under the umbrella of the Major Economies Forum. The 17 countries in the forum are responsible for 80% of greenhouse gas emissions.

Brown told them: “In every era there are only one or two moments when nations come together and reach agreements that make history, because they change the course of history. Copenhagen must be such a time. There are now fewer than 50 days to set the course of the next 50 years and more.