The UN’s World Meteorological Organisation has declared the hottest decade on record during 2011 to 2020, with the past year set to be among the top three warmest years.
The Earth’s average temperature in 2020 was about 1.2C higher than the 1850-1900 average, according to the latest research published on Wednesday, as global warming becomes more pronounced.
One unusual feature of 2020 is that it has been such a hot year even despite the current La Niña, a weather pattern in the Pacific Ocean which usually has a cooling effect on global temperatures.
“2020 has, unfortunately, been yet another extraordinary year for our climate,” said WMO secretary-general Petteri Taalas. “Despite the current La Niña conditions, this year has already shown near record heat comparable to the previous record of 2016.”
The data from the WMO coincided with a strident speech from UN secretary-general António Guterres, who warned that the world was on a “suicidal” path.
“Nature always strikes back — and it is already doing so with growing force and fury,” he said, in an online speech at Columbia University. “Apocalyptic fires and floods, cyclones and hurricanes are increasingly the new normal.”
Mr Guterres said the world needed to decrease fossil fuel production by 6 per cent a year, over the next decade, to limit global warming to less than 1.5C.
The secretary-general has gone much further than his predecessors to champion climate change action, including calling for the end of the use of coal and asking all countries to adopt net zero emissions targets.
“Making peace with nature is the defining task of the 21st century. It must be the top, top priority for everyone, everywhere,” he said.
During a year in which fighting coronavirus has been a high priority for many governments, some efforts to tackle climate change have been delayed, including the UN climate change conference known as COP26, which has been pushed back by a year.
This year has also been marked by a number of unusual weather events and natural disasters linked to climate change, including a record-breaking hurricane season in the north Atlantic, and a major heatwave in the Siberian Arctic region.
Ocean heat also reached record levels in 2020, according to the World Meteorological Organisation report, which contributes to more powerful hurricanes forming.
Devastating wildfires across the US west coast, South America, and Australia underscore the impact of higher temperatures, the WMO added.
This year currently ranks as the second-hottest year on record, just behind 2016 and ahead of 2019, however the difference between the years is very small, so the ranking could change as data from the final weeks of 2020 come in.
While the economic recession caused by the coronavirus pandemic has caused emissions to drop this year, the level of carbon dioxide in the atmosphere is still increasing — because it can linger in the air for up to a century.
A series of new climate targets, including a pledge from China to reach carbon neutrality by the middle of the century, could help reduce the pace of global warming.
However those goals are still not sufficient to limit global warming to well below 2C, the level agreed by the 2015 Paris accord.