A substantial rise in atmospheric methane levels helped push global temperatures in 2021 towards the highest ever recorded, according to the EU’s Copernicus Climate Change Service. A new report released Monday determined that last year was the fifth warmest in the 52-year European record, slightly hotter than 2015 and 2018. The last seven years rank as the hottest on record, and 21 of the 22 warmest years have occurred since 2000.
Pollution from fossil-fuel combustion, industrial activity and other human sources is causing temperatures to rise. A global consortium of climate scientists backed by the United Nations said with “unequivocal” confidence in an August report that human-made pollution is causing the warming trend. A major factor that kept 2021 from matching record heat levels was the ongoing La Niña event, an occasional natural cooling in the equatorial Pacific that’s expected to last through the early months of 2022.