CO2 levels highest in 3 million years - UN

The UN's annual report, the Greenhouse Gas Bulletin, shows CO2 levels have risen faster than anticipated in the past year to hit a level not seen for more than three million years. The new report has raised alarm among scientists and prompted calls for nations to consider more drastic emissions reductions at the upcoming climate negotiations in Bonn. One of those scientists is Dave Reay, professor of carbon management at the University of Edinburgh. He tells us it's a combination of human activities and a strong El Niño event which has contributed to the rise.