GENEVA — Carbon dioxide levels in the atmosphere reached a record high in 2013 as increasing levels of man-made pollution transform the planet, the U.N. weather agency said Tuesday.
The heat-trapping gas blamed for the largest share of global warming rose to global concentrations of 396 parts per million last year, the biggest year-to-year change in three decades, the World Meteorological Organization said in an annual report.
That’s an increase of 2.9 ppm from the previous year and is 42 percent higher than before the Industrial Age, when levels were about 280 parts per million.
Based on the current rate, the world’s carbon dioxide pollution level is expected to cross the 400 ppm threshold by 2016, said WMO Secretary-General Michel Jarraud. That is way beyond the 350 ppm that some scientists and environmental groups promote as a safe level and which was last seen in 1987.
CO2 emissions are growing mainly in China and other large developing countries as their economies expand. So far developed and developing countries have failed to reach a binding pact that would curb emissions globally. The goal of U.N. climate talks is to deliver such an agreement next year.