November 26, 2007
Atmosphere carbon dioxide levels highest on record, says World Meteorological Organization
Geneva, Switzerland – Globally averaged concentrations of carbon dioxide (CO2) in the atmosphere reached their highest levels ever recorded in 2006, according to a bulletin from the World Meteorological Organization (WMO). The report says that levels reached 381.2 parts per million (ppm), up 0.53 per cent from 379.2 ppm in 2005.
The information is based on observations from the WHO Global CO2 and CH4 Monitoring Network, a climate network recognized by the United Nations Framework Convention on Climate Change.
After water vapour, the three most prevalent greenhouse gases in the Earth’s atmosphere are carbon dioxide, methane (CH4) and nitrous oxide (N2O), respectively. Concentrations of N2O also reached record highs in 2006, up 0.25 per cent from 2005, while methane remained almost unchanged.
The report says that the 36 per cent rise in CO2 since the late 1700s has largely been generated by emissions from the combustion of fossil fuels, while around one-third of N2O discharged into the air is the result of human activities such as fuel combustion, biomass burning, fertilizer use and some industrial processes. Human activity such as fossil fuel exploitation, rice agriculture, biomass burning, landfills and ruminant farm animals account for some 60 per cent of atmospheric methane, with natural processes such as wetlands and termites responsible for the remaining 40 per cent.