GENEVA - The United Nations weather agency says the three main greenhouse gases in the Earth's atmosphere have reached new record highs.
Geir Braathen of the World Meteorological Organization says carbon dioxide was up the most in 2007, one-half per cent, with methane and nitrous oxide rising by lesser amounts.
Braathen says that it was the first time in a decade that the concentration of methane in the atmosphere has increased.
He said Tuesday that it is too soon to say what caused the increases.
The gases are produced partially by natural sources, like wetlands, and partially by human activities such as fertilizer use or fuel combustion.
A UN panel has warned that continued increases will have catastrophic consequences, such as severe droughts and floods.
