climate models underestimating GHG

Data published by the US National Oceanic and Atmospheric Administration now shows not only that concentrations of atmospheric carbon dioxide are rising, but that they are rising at an increasing rate that is higher than expected.

Scientists at the Mauna Loa observatory in Hawaii say that CO2 levels in the atmosphere now stand at 387 parts per million (ppm), up almost 40% since the industrial revolution and the highest for at least the last 650,000 years.

[...]

Scientists say the shift could indicate that the Earth is losing its natural ability to soak up billions of tonnes of CO2 each year. Climate models assume that about half our future emissions will be reabsorbed by forests and oceans, but the new figures confirm this may be too optimistic. If more of our carbon pollution stays in the atmosphere, it means emissions will have to be cut by more than is currently projected to prevent dangerous levels of global warming.

[via the Guardian]