Those hoping new United States President Joe Biden would make action on climate change one of his top priorities would have been cheered by the flurry of activity from his first days in office.

With a few strokes of his pen, Biden cancelled a Trump administration permit for the $US8 billion ($10.3 billion) Keystone XL pipeline linking Canada’s oil sands to the Gulf coast, slapped a moratorium on oil and gas leases in Alaska’s pristine Arctic National Wildlife Refuge, began a review of pollution regulations and ordered that the US rejoin the Paris climate agreement 77 days after it had formally left it.

And kicking off the new administration’s first full day in office, Biden’s special climate envoy, John Kerry, was up at Washington’s crack of dawn to tell business leaders of G20 nations the US was on the “road back to progress” on climate action after “four wasted years” under Donald Trump.

“The early hour is appropriate because we really don’t have a minute to waste,” Kerry said, adding that “very few” nations were on a trajectory of cutting greenhouse emissions to meet even the current goals, “let alone the targets we need to avert catastrophic damage”.

Read the full article on The Sydney Morning Herald website, featuring Prof Howard Bamsey