BBC: The levels of gases in the atmosphere that drive global warming increased to a record high in 2012.
According to the World Meteorological Organization (WMO), atmospheric CO2 grew more rapidly last year than its average rise over the past decade.
Concentrations of methane and nitrous oxide also broke previous records
Thanks to carbon dioxide and these other gases, the WMO says the warming effect on our climate has increased by almost a third since 1990.
The WMO's annual greenhouse gas...