U.N. sounds alarm over nitrous oxide


Levels of nitrous oxide, a gas that depletes the ozone layer and stokes global warming, could nearly double by midcentury, the United Nations warned in a recent report coinciding with the world climate talks in Warsaw.

Analysis by scientists from 35 organizations found that nitrous oxide is now the most important ozone-depleting gas and the third most powerful greenhouse gas being emitted into the atmosphere, the U.N. Environment Program (UNEP) said.

On current trends, nitrous oxide concentrations will rise by 83 percent by 2050 compared to 2005, the experts found.

Nitrous oxide exists naturally in the atmosphere in trace amounts, released as part of the exchange of nitrogen between the land and the air.

But levels of it have zoomed in the past decades, driven mainly by industrially made nitrogen fertilizer in agriculture, pollution from road transport and emissions from the chemical industry.

The gas damages protective ozone molecules in the stratosphere, which help shield Earth from dangerous ultraviolet light.