Post by Arxileas on Nov 29, 2007 8:38:55 GMT -5
Two of the most important Greenhouse gases in the Earth's atmosphere reached a record high in 2006, and measurements show that one - carbon dioxide - is playing an increasingly important role in global warming, the U.N. weather agency said Friday. The global average concentrations of carbon dioxide, or CO2, and nitrous oxide, or N2O, in the atmosphere were higher than ever in measurements coordinated by the World Meteorological Organization, said Geir Braathen, a climate specialist at the Geneva-based agency. Methane, the third of the three important greenhouse gases, remained stable between 2005 and 2006, he said. Braathen said measurements show that CO2 is contributing more to global warming than previously. CO2 contributed 87 percent to the warming effect over the last decade, but in the last five years alone, its contribution was 91 percent, Braathen said. "This shows that CO2 is gaining importance as a greenhouse gas," Braathen said. The concentration of carbon dioxide in the atmosphere rose by about half a percent last year to reach 381.2 parts per million, according to the agency. Nitrous oxide totaled 320.1 parts per billion, which is a quarter percent higher than in 2005. Braathen said it appears the upward trend will continue at least for a few years. The World Meteorological Organization's annual Greenhouse Gas Bulletin provides widely accepted worldwide data on the amount of heat-trapping greenhouse gases in the atmosphere. Studies have shown that human-produced carbon dioxide emissions heat the Earth's surface and cause greater water evaporation. That leads to more water vapor in the air, which contributes to higher air temperatures.
CO2, methane and N2O are the most common greenhouse gases after water vapor, according to the meteorological organization. They are produced by natural sources, such as wetlands, and by human activities such as fertilizer use or fuel combustion. There is 36.1 percent more carbon dioxide in the atmosphere than there was in the late 18th century, primarily because of combustion of fossil fuels, the World Meteorological Organization bulletin said.
news.yahoo.com/s/ap/20071123/ap_on_sc/greenhouse_gases;_ylt=Arhlz6GlWKshr9VAjNNh241vieAA
CO2, methane and N2O are the most common greenhouse gases after water vapor, according to the meteorological organization. They are produced by natural sources, such as wetlands, and by human activities such as fertilizer use or fuel combustion. There is 36.1 percent more carbon dioxide in the atmosphere than there was in the late 18th century, primarily because of combustion of fossil fuels, the World Meteorological Organization bulletin said.
news.yahoo.com/s/ap/20071123/ap_on_sc/greenhouse_gases;_ylt=Arhlz6GlWKshr9VAjNNh241vieAA