The United Nations World Meteorological Organization (WMO) says greenhouse gases, which drive global warming, continue to increase and carbon dioxide concentrations reached their highest level ever in 2007.
The WMO’s latest “Greenhouse Gas Bulletin” says the amount of carbon dioxide in the atmosphere rose 0.5 percent from 2006 to 2007, while concentrations of nitrous oxide, another climate-warming substance, also reached record highs in 2006, the latest year for which it has figures.
The WMPO says carbon dioxide levels have soared 37 per cent in the last 25years with population growth and urban development propelling increased burning of fossil fuels such as oil and coal.
Also contributing to the surging CO2 levels is the clearing of land for farming, which releases more of the gas into the air and slashes carbon uptake by the biosphere.
The new report said it is too early to judge whether there is an upward trend in levels of methane, another greenhouse gas, whose concentrations have been fluctuating over the past decade.
It also found that the amount of chlorofluorocarbons (CFCs), which are ozone-damaging chemicals, continue to drop, thanks to emissions reductions set under the UN`s Montreal Protocol that entered into force in 1989.
Meanwhile, a consortium including the UN Food and Agriculture Organisation says Africa could be absorbing more carbon dioxide from the atmosphere than the continent is releasing into it.
CarboAfrica found that Africa contributes less than 4% of the global emissions from fossil fuels, but accounts for 17% and 40% respectively of gas emissions emanating from deforestation and fires.
But the most important element is the balance between carbon captured through photosynthesis by Africa`s forests and savannas and gas released into the atmosphere, the research project comprised of 15 institutions said.
“Our evidence so far indicates that Africa seems a ‘carbon sink,` meaning that it takes more carbon out of the atmosphere than it releases,” said Riccardo Valenti, coordinator of CarboAfrica.
“If confirmed, this implies that Africa contributes to reducing the greenhouse effect, thus helping mitigate the consequences of climate change.”