Greenhouse gas emissions are on course to be about 30 per cent above the 2030 global target, but not even President Donald Trump can stop the move away from fossil fuels, the United Nations says.
Trump says he'll pull out of the Paris climate agreement under which 195 countries pledged to try to keep global warming to "well below" 2 degrees Celsius above pre-industrial times.
An annual UN audit of progress towards that goal showed emissions are likely to be 53.0-55.5 billion tonnes of carbon dioxide equivalent per year by 2030, far above the 42 billion tonne threshold for averting the 2 degree rise.
But UN Environment chief Erik Solheim hailed signs of progress, with an apparent three-year plateau in carbon dioxide emissions from fossil fuels, cement production and other industrial processes, largely due to slower growth in coal use in China and the US.
"We all know the bad news. In my view however we are at a turning point where the good news is taking precedence from the bad news," he said.
"We are at a watershed moment where we have stopped the rise in CO2 emissions, there is every reason to believe we can bring them down, and we see great news coming from all over the world every day," Solheim said by video link from Nairobi.
He said whenever he's asked "What about Donald Trump?" he answers that the momentum was now with private sector efforts to combat climate change which Trump would not be able to stop.
"In all likelihood the United States of America will live up to its commitments not because of the White House but because of the private sector," he said. "The train is on the right track, but our duty is to speed it up."
The UN says greater efforts will be needed because temperatures are set to rise by 3.0-3.2 degrees Celsius this century.
