Pandemic backdrop to historic global temps

While the coronavirus pandemic propelled 2020 into medical history, the year's global temperatures have topped the list for being the hottest on record.

Scientists at US space agency NASA have found last year tied with 2016 for the warmest ever, with average global temperatures 1.02 degrees Celsius higher than the baseline between 1951 to 1980.

NASA's Gavin Schmidt says the last seven years have been the warmest seven on record, showing the dramatic trend.

"Whether one year is a record or not is not really that important, the important things are long-term trends," he said.

"With these trends, and as the human impact on the climate increases, we have to expect that records will continue to be broken."

Another US agency, the National Oceanic and Atmospheric Administration, has declared 2020 the second hottest on record behind 2016.

But NASA says the difference between the two years is so small, and within the margin of error, that they were effectively tied.

NASA's data also includes polar regions, unlike NOAA's.

The analysis comes after the Bureau of Metereology's annual climate statement showed 2020 was the fourth-warmest year on record for Australia.

Average mean temperatures for last year were 1.15 degrees Celsius above the 1961 to 1990 average.

Climate Council spokesman Will Steffen says the latest data sets off more alarm bells.

"We all need to step up - and fast," Professor Steffen said.

"2021 needs to be a year of climate action because failure is not an option."

Australia is increasingly isolated due to the federal government not committing to a timeframe for achieving net zero emissions.

The government recently resubmitted its climate pledges to the United Nations, which says Australia's goal to achieve net zero emissions is "as soon as possible".

The document did not boost the government's 2030 target of a 26 to 28 per cent reduction on levels compared to 2005 levels but says it wants to "overachieve" on it.