The United Nations warned on Wednesday that the past decade was the hottest on record, with 2019 confirmed as the second-hottest year in history.

The hottest year ever recorded was 2016.

"Since the 1980s each decade has been warmer than the previous one," the World Meteorological Organization (WMO) said in a statement, adding that "this trend is expected to continue."

The WMO's findings are based on leading data sets from around the world.

"The year 2020 has started out where 2019 left off — with high-impact weather and climate-related events," said WMO chief Petteri Taalas. "Unfortunately, we expect to see much extreme weather throughout 2020 and the coming decades, fueled by record levels of heat-trapping greenhouse gases in the atmosphere."

Taalas pointed specifically to the bushfires ravaging Australia, which have killed at least 28 people, displaced tens of thousands, and killed up to 1 billion animals.

Oceans hit the hardest

The UN has said that man-made emissions need to decrease by 7.6% a year until 2030 in order to limit the temperature rise to 1.5 degrees Celsius (2.7 degrees Fahrenheit), a pledge that many nations signed off on in the Paris climate agreement.

Modern weather record-keeping began in 1850. According to Taalas, the average global temperature has increased by 1.1 degrees Celsius since then. Since most of the world's heat is stored in its oceans, marine life and ecosystems have been the hardest hit, evidenced by mass die-offs of fish and widespread coral bleaching.

"On the current path of carbon dioxide emissions, we are heading towards a temperature increase of three to five degrees Celsius by the end of the century," Taalas said.

es/stb (AFP, Reuters)

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