Record level of greenhouse gases raise concern over climate change.

The levels of gases in the atmosphere that drive global warming reached a record high last year.

The annual figures released by the World Meteorological Organisation – the WMO – showed that the volume of carbon dioxide or CO2, which is the primary gas emitted by human activities grew faster in 2012 than in the previous decade.

The WMO’s annual greenhouse gas bulletin measures concentrations in the atmosphere, not emissions on the ground. It fired a warning for the future.

“CO2 is a very stable gas, so it means that there is no sort of chemical reaction which would destroy naturally the CO2 from the atmosphere, so it stays for very long periods, hundreds of years and even more, and that’s why as a consequence the actions we take now, or the actions we don’t take now will have consequences for a very, very long period,” Michel Jarraud, Secretary-General of the World Meteorological Organisation told reporters.

The climate system is dominated by the oceans rather than the atmosphere the WMO pointed out and the time needed to warm the seas meant the full impact of today’s figures would only be felt later.

Delegates from over 190 nations will meet in Warsaw next week for a UN conference to work on emission cuts under a new climate pact to be signed by 2015 and which would come into force in 2020.