BARACK Obama is being pressed for proof of his intent to act on climate change before next week’s United Nations global warming summit in Doha. The proof might boil down to an early statement that America remains committed to the global goal of limiting warming to 2ºC above pre-industrial levels.

Every statement from US diplomats at the Doha negotiations will be closely scrutinised for signs that Obama will indeed make climate change a priority of his second term — and that America remains committed to the global agreement diplomats have been seeking for 20 years.

Campaigners say Obama’s re-election, superstorm Sandy and endorsement by the New York City mayor, Michael Bloomberg — predicated on climate change — have put global warming back on the domestic agenda.

Opinion polls suggest public concern in the US about climate change was rising even before Sandy. Campaigners argue Obama needs to engage on the issue if he wants to safeguard his legacy as president. Early indications are that Obama will spend more time on climate change than in his first term.

At Doha, observers will be watching whether Todd Stern, the State Department climate envoy, reaffirms America’s commitment to the climate platform reached in Durban last year, including a core goal of limiting warming to 2ºC. Some campaigners fear the US is backing away from that promise, following a speech at Dartmouth University this year in which Stern said signing up to the 2ºC goal was unrealistic for some countries.

The larger question, however, is how Obama intends to use his authority to act on climate in his second term — even if Congress remains opposed to additional regulations.

Even after Obama’s re-election, the House of Representatives is still controlled by Republicans, including a heavy contingent from the Tea party conservatives who discount the very existence of climate change and oppose government intervention in the economy.

But campaign groups in the US are hoping the Environmental Protection Agency finalises a rule approved in March that would put severe limits on the construction of power plants. — The Guardian, London