Climate change models underestimate likely temperature rise, report shows [View all]

[IDemo]

The Earth’s climate is far more sensitive to carbon dioxide emissions than previously thought, heightening the likelihood of a 4C temperature rise by 2100, new Australian-led research of cloud systems has found.

The study, published in Nature, provides new understanding on the role of cloud formation in climate sensitivity – one of the key uncertainties in predictions of climate change.

Report authors Steven Sherwood, Sandrine Bony and Jean-Louis Dufresne found climate models which show a low global temperature response to CO2 emissions do not factor in all the water vapour released into the atmosphere.

Models typically simulate water vapour as rising to 15km and forming clouds, rather than updraughts of water vapour that rise only a few kilometres and pull away the cloud-forming vapour. This prediction of cloud cover is important because clouds reflect sunlight, lessening the impact of global warming.

http://www.theguardian.com/science/2014/jan/01/climate-change-models-underestimate-likely-temperature-rise-report-shows