Ken Pedersen, expedition leader at the Norwegian Troll Research Station in Antarctica, briefs a group of visiting environment ministers and other representatives from more than a dozen nations on Monday. The group flew to the remote station to learn from international scientists about whether and how global warming may melt Antarctic ice, raising sea levels.

Troll Research Station, Antarctica ? Policymakers met polar explorers on the boundless ice of Antarctica Monday as a U.S.-Norwegian scientific expedition came in from the cold to report on the continent’s ice sheets, a potential source for a catastrophic “big melt” from global warming.

“Our preliminary finding is that there’s a slight warming trend in East Antarctica,” American glaciologist Ted Scambos told the group of visiting environment ministers.

It was an early estimate regarding just one region of a huge continent, drawn from first analyses of ice cores drilled along the team’s route. But it caught the ear of the visiting politicians, who are this year weighing a grand new global deal for cutting greenhouse-gas emissions to avert the worst of climate change.

“It’s important to hear the latest science,” said Hilary Benn, Britain’s environment minister. “I was impressed that they’re finding temperatures rising. But there is still so much not known.”

Representatives from more than a dozen nations, including the U.S., China and Russia, rendezvoused at this Norwegian research station with the scientists completing the last leg of a 1,400-mile, two-month trek over the ice from the South Pole.

The 12-member Norwegian-American Scientific Traverse of East Antarctica was a leading project in the 2007-2009 International Polar Year (IPY). It is a mobilization of 10,000 scientists and 40,000 others from more than 60 countries engaged in intense Arctic and Antarctic research over the past two southern summer seasons — on the ice, at sea, via icebreaker, submarine and surveillance satellite.

Learning more about historic temperature trends has been a prime concern in examining whether global warming — already occurring elsewhere on the planet — might cause Antarctica’s huge store of ice to start melting, raising sea levels, potentially to a disastrous point for coastal cities and shorelines worldwide.

Speaking to the environment ministers over breakfast, Kim Holmen, research director for the Norwegian Polar Institute, the Troll station’s operator, noted that scientists had generally thought Antarctica as a whole was not warming in recent decades. But a recent study in the journal Nature shook that view.

“This new analysis shows us actually the whole of Antarctica has been warming,” Holmen said.

The preliminary finding from the on-the-ground Traverse expedition — if it is confirmed — would reinforce that Nature study, which extrapolated temperature trends by blending satellite information with scarce weather-station data available in and around Antarctica.