UN: CO2 levels RECORD HIGH

2The UN weather agency says the global atmospheric concentration of carbon dioxide hit an all-time high in 2013.

The World Meteorological Organization released on Tuesday the results of last year's research on levels of CO2 and other greenhouse gases. The WMO's assessment is based on data from weather authorities and research institutes from around the world.

The report says the average volume of CO2 in the atmosphere hit a record high of 396 parts per million last year.

The figure rose by 2.9 parts per million from 2012. It's the largest annual increase since monitoring began in 1984.

The report says the concentration of nitrous oxide was 325.9 parts per billion and the volume of methane reached 1,824 parts per billion. Both are new record highs.

WMO officials say emissions of heat-trapping gases need to be cut by 80 percent, to keep the rise of temperatures within one degree Celsius until 2100.

They also warn that CO2 will keep dissolving into the oceans, making them more acidic. They say if this trend continues, it would affect marine ecology.

An official at Japan's Meteorological Agency says carbon dioxide levels grew rapidly, despite calls for measures to combat global warning.

He says people should know that if the average global temperature rises by one degree, the risk of extreme atmospheric conditions will increase.