US Secretary of State John Kerry made an impassioned plea Sunday for America to maintain action on global warming, despite the election of climate-change denier Donald Trump.

While US President-elect Trump has labelled climate change a hoax and threatened to pull out of the Paris emissions deal, Kerry said most Americans wanted the problem addressed.

"We will wait to see how the next administration addresses this but I believe we're on the right track and this is a track that the American people are committed to," Kerry told reporters on a trip to New Zealand.

"The majority of the American people believe that climate change is in fact happening and want to see us address it."

Trump has pledged to ditch Washington's climate change policies, causing consternation among diplomats leading global efforts to curb greenhouse gas emissions.

Kerry was hopeful Trump would not follow through on his fiery campaign rhetoric.

"Everybody knows that there's sometimes a divide between a campaign and the governing and I think the next administration needs to define itself on that subject," he said.

Kerry was speaking after an "awe-inspiring" visit to Antarctica, where he took a helicopter ride to view the West Antarctic Ice Sheet.

"That ice sheet alone, should it break up and melt, as it is showing signs of doing now, would add some 12 feet (3.7 metres) or more to the current sea level," he said.

Washington's top diplomat said scientists in the frozen continent showed him the work they were doing to assess the impact of climate change.

He said it reinforced his conviction that action was needed and he would take that message to UN climate talks in Morocco next week.

"Until January 20, when this administration is over, we intend to do everything possible to meet our responsibility to future generations to be able to address this threat to life itself on the planet," he said.

The Marrakesh talks, which wrap up on November 18, are examining ways to implement the landmark Paris pact agreed to by 196 nations last year.

It undertakes to limit global warming to "well below" two degrees Celsius (3.6 degrees Fahrenheit) over pre-Industrial Revolution levels, and to strive for 1.5 C.

Without the United States -- the world's second largest greenhouse gas emitter and a major donor to climate change mitigation funds -- the task becomes much more difficult.

- 'Beyond any doubt' -

Kerry said he first became involved in the climate issue in the early 1990s and had seen scientific evidence of change grow to a level that was now overwhelming.

"The world's scientific community has concluded that climate change is happening beyond any doubt, and the evidence is there for everybody to see," he said.

"The question now, and which this administration continues to address, is how to implement the Paris agreement."

He cited Pacific island nations threatened by rising seas, more intense and damaging storms, as well as greater frequency of wildfires and flooding.

Kerry said the United States spent $8.0 billion last year alone cleaning up after storms whipped into unprecedented ferocity by the changing climate.

He said it was an issue that leaders could not ignore.

"The evidence is mounting, in ways that people in public life should not dare to avoid accepting as a mandate for action," he said.