US President Barack Obama urged an international conference on the Arctic on Monday to unite now to slow climate change, or else face a dire future.

"The climate is changing faster than our efforts to address it," he warned the US-hosted Glacier conference in Anchorage, Alaska. "That, ladies and gentlemen, must change."

Without swift, united action to slow global warming, he said, "people will suffer. Economies will suffer. Entire nations will find themselves under severe, severe problems" including drought, floods, rising sea levels, refugees, scarcity and conflict.

Obama addressed the Glacier conference – an acronym for Global Leadership in the Arctic: Co-operation, Innovation, Engagement and Resilience – on the first day of a three-day tour of Alaska designed to highlight his climate agenda.

Alaska is on the "leading edge" of climate change, he said, with temperatures rising twice as quickly as global averages and a loss of 75 gigatons of glacier ice per year.

Before the conference's start, representatives of Britain, France, Germany, Italy, Japan, South Korea, the Netherlands, Poland, Singapore, Spain and the European Union agreed with him, vowing to take "urgent action to slow the pace of warming in the Arctic".

In a joint statement, they said that they take seriously scientific warnings about warming in the Arctic that is proceeding at twice the global rate and warn that shrinking glaciers and melting snow and ice in the region could speed up the impacts of climate change.

Obama said, those impacts are already here.

"Climate change is no longer some far-off problem," Obama said. "It is happening here. It is happening now."

Melting sea ice and permafrost endanger Arctic communities with erosion and storms, and ocean acidification and climate-driven animal migration changes threaten indigenous people and local economies, he said.

Obama said he would speak more about the challenges facing Alaska and announce measures to address them during the course of his trip.

Before the conference, Obama met with representatives of Alaskan native communities. On Tuesday, he will hike to the Exit Glacier, and tour the Kenai Fjords National Park by boat. On Wednesday, he will travel to the Arctic – the first sitting US president to do so – to meet with fishermen and families in the towns of Dillingham and Kotzebue.

Their concerns, Obama said, should be the concerns of the world.

"It's urgent for them today, but that is the future for all of us if we don't take care," he said.

Echoing calls by conference participants for "ambitious" outcomes of a UN-sponsored climate summit in Paris later this year, Obama said only united action could turn the tide.

"This year in Paris has to be the year that the world finally reaches an agreement to protect the one planet that we've got while we still can," he said.

In a withering challenge to those who dispute science showing humans' impact on the climate, Obama said, "the time to plead ignorance is surely past."

"Those who want to ignore the science are increasingly on their own. They're on their own shrinking island," he said, to laughter and sustained applause.

News24.com/DPA