Greenhouse gas levels in the atmosphere have reached record breaking levels again, according to a report released by the United Nations World Meteorological Organization (WMO) on Thursday.
Observations from the WMO Global Atmosphere Watch (GAW) show that carbon dioxide levels in the air stood at 405.5 ± 0.1 parts per million (ppm) in 2017, showing an increase by 2.2 ppm since 2016. Methane levels were recorded at 1859 ± 2 parts per billion (ppb), rising by 7 ppb since the previous year. Nitrous oxide levels stood at 329.9 ± 0.1 ppb, depicting a rise by 0.9 ppb since 2016. All the three gases have risen by levels that are practically equal to the average increases over the previous decade. This proves that so far, humanity has been unable to reverse emission trends that are damaging the environment.
Furthermore, the slowdown in methane and carbon dioxide emissions noted in 2017 was also attributed to the El Nino event, the warm phase of the El Nino southern oscillation which peaked in 2015 and 2016. This caused droughts in some regions which reduced the ability of forests and vegetation to absorb carbon dioxide, as a result of which gas levels rose by higher amounts in 2016.
Researchers also found the resurgence of a banned gas called CFC-11. The gas is mostly used in home insulation. Earlier this year the Environmental Investigation Agency — a UK-based non-governmental organization — traced CFC-11 production to a number of factories across China.
Scientists at the WMO have said that carbon dioxide levels this high have not been observed in a very long time. “The last time the Earth experienced a comparable concentration of CO2 was 3-5 million years ago, when the temperature was 2-3C warmer and sea level was 10-20 metres higher than now,” WMO Secretary-General Petteri Taalas told the press.
Carbon Dioxide levels in the atmosphere are now 46 percent higher than levels before the industrial revolution.