Greenhouse gas concentrations hit record high: WMO report

The amount of greenhouse gases in the atmosphere reached yet another new record high in 2014, according to a new report released Monday by the World Meteorological Organization (WMO).

The report, titled "Greenhouse Gas Bulletin", said that between 1990 and 2014 there was a 36-percent increase in radiative forcing, the warming effect on our climate, because of long-lived greenhouse gases such as carbon dioxide, methane and nitrous oxide from industrial, agricultural and domestic activities.

"Every year we report a new record in greenhouse gas concentrations," said WMO Secretary-General Michel Jarraud.

"Every year we say that time is running out. We have to act now to slash greenhouse gas emissions if we are to have a chance to keep the increase in temperatures to manageable levels," Jarraud noted.

The most important long-lived greenhouse gas, carbon dioxide, accounted for about 83 percent of the total increase in radiative forcing by long-lived greenhouse gases over the past decade.

Atmospheric concentrations of carbon dioxide reached 397.7 parts per million (ppm) in 2014, which is 143 percent of pre-industrial levels.

In the northern hemisphere carbon dioxide concentrations crossed the symbolically significant 400 ppm level in 2014 spring, when CO2 is most abundant. In spring 2015, the global average concentration of carbon dioxide crossed the 400 ppm barrier. The global annual average is likely to pass 400 ppm in 2016.

Atmospheric methane reached a new high of about 1,833 parts per billion (ppb) in 2014 and is now 254 percent of the pre-industrial level. In addition, nitrous oxide concentration in 2014 was about 327.1 ppb, equals to 121 percent of pre-industrial levels.

WMO said the Bulletin provided a scientific base for decision-making ahead of the UN climate change negotiations in Paris to be held from Nov. 30 to Dec. 11. Endit