UN: Heat-trapping gas surges beyond milestone

The World Meteorological Organization says heat-trapping gases in Earth’s atmosphere are growing faster than before, surging permanently beyond a troubling milestone.

The United Nations agency says global carbon dioxide levels, which first reached 400 parts per million last year, are likely to stay above that symbolic 400 milestone all year and for generations to come.

Carbon dioxide levels overall rise because of the burning of fossil fuels; they also fluctuate seasonally, peaking in May and dipping in September. Last month’s average level at a key Hawaii monitoring station was 401 parts per million, up from 313 in 1958.

U.N. spokesman Stephane Dujarric said Monday that the rise was fueled by El Niño, a weather pattern caused by the warming of the Pacific Ocean. El Niño leads to droughts in tropical regions and reduces the capacity of forests and oceans to absorb carbon dioxide, the greenhouse gas blamed for global warming.

Methane and other heat-trapping gases are also spiking. The WMO issues its annual greenhouse gas bulletin, using public data, before international climate talks.