The last four years were the hottest since global temperature records began, the UN confirmed on Wednesday in an analysis that it said was a “clear sign of continuing long-term climate change.”
The UN’s World Meterological Organization said in November that 2018 was set to be the fourth warmest year in recorded history, stressing the urgent need for action to rein in runaway planetary warming.
On Wednesday it incorporated the final weeks of last year into its climate models and concluded that average global surface temperature in 2018 was 1 degree Celsius (1.8 Fahrenheit) above pre-industrial baseline levels.
2016, boosted by a strong El Nino that normally tips the mercury northwards, remains the hottest year on record.
It also said that the 20 warmest years in history all occurred within the last 22 years. “The long-term temperature trend is far more important than the ranking of individual years, and that trend is an upward one,” said WMO Secretary-General Petteri Taalas.
“The degree of warming during the past four years has been exceptional, both on land and in the ocean.”
The WMO said heightened temperatures also contributed to a number of extreme weather events such as hurricanes, droughts and flash flooding.