Updated Saturday, November 24, 2012 at 06:01 PM
DOHA, Qatar — During a year with a monster storm and scorching heat waves, Americans have experienced the kind of freakish weather that many scientists say will occur more often on a warming planet.
And as a re-elected president talks about global warming again, climate activists are cautiously optimistic that the U.S. will be more than a disinterested bystander when the U.N. climate talks resume Monday with a two-week conference in Qatar.
"I think there will be expectations from countries to hear a new voice from the United States," said Jennifer Morgan, director of the climate and energy program at the World Resources Institute in Washington, D.C.
The climate officials and environment ministers meeting in the Qatari capital, Doha, will not come up with an answer to the global temperature rise that is melting Arctic sea ice and permafrost, raising and acidifying the seas, and shifting rainfall patterns, which has an impact on floods and droughts.
Instead, they will focus on side issues, such as extending the Kyoto Protocol — an expiring emissions pact with a dwindling number of members — and ramping up climate financing for poor nations.
They will also try to structure the talks for a new global-climate deal that is supposed to be adopted in 2015, a process in which U.S. leadership is considered crucial.
"We need the U.S. to engage even more," said European Union Climate Commissioner Connie Hedegaard. "Because that can change the dynamic of the talks."
The world tried to move forward without the U.S. after the Bush administration abandoned the Kyoto Protocol, a 1997 pact limiting greenhouse emissions from industrialized nations.
The concentration of heat-trapping gases such as carbon dioxide has jumped 20 percent since 2000, primarily from the burning of fossil fuels such as coal and oil, according to a U.N. report released last week. And each year, the gap between what researchers say must be done to reverse this trend, and what's being done, gets wider.
The U.S., alone among industrialized countries, didn't ratify the Kyoto Protocol because it found it unfair that China and other emerging economies, as developing countries, were not covered by any binding emissions targets.
The U.S. and other rich countries say that firewall must be removed as the talks enter a new phase aimed at adopting a new climate treaty by 2015 that applies to all countries.
China — now the world's top carbon emitter — wants to keep a clear dividing line between developed and developing countries, noting that historically, the former bear the brunt of the responsibility for man-made climate change.
The issue is unlikely to be resolved in Doha.