Methane concentrations in the atmosphere made their biggest-ever registered increase in 2021, as all three main greenhouse gases extended their record high levels, the United Nations said Wednesday.
The UN's World Meteorological Organization said levels of climate-warming carbon dioxide, methane and nitrous oxide all reached new records last year.
The figures, released in the UN weather agency's Greenhouse Gas Bulletin, underlined "the enormous challenge—and the vital necessity—of urgent action to cut greenhouse gas emissions and prevent global temperatures rising even further in the future," said WMO chief Petteri Taalas. And NASA scientists, using a tool designed to study how dust affects climate, announced Tuesday they have so far identified more than 50 spots around the world emitting major levels of methane.Atmospheric methane is the second largest contributor to climate change. Since 2007, globally-averaged atmospheric methane concentrations have been increasing at an accelerating rate, the WMO said.
The causes of last year's methane rise are still being investigated, but analysis indicates that the largest contribution to the increase since 2007 comes from sources such as wetlands or rice paddies. "As the top and most urgent priority, we have to slash carbon dioxide emissions, which are the main driver of climate change and associated extreme weather, and which will affect the climate for thousands of years through polar ice loss, ocean warming and sea level rise," he said.