Earth's sensitivity to climate change could be 'double' previous estimates, say geologists
The sensitivity of the Earth's climate to CO2 could be double what has been previously estimated, according to a statement issued by the Geological Society of London.
In an addendum to 2010's 'Climate change: Evidence from the Geological Record', the statement notes that many climate models typically look at short term, rapid factors when calculating the Earth's climate sensitivity – defined as the mean global temperature increase brought about by a doubling of atmospheric CO2.
It is well known that a doubling of atmospheric CO2 levels could result in temperature increases of between 1.5 and 4.5°C, due to fast changes such as snow and ice melt, and the behaviour of clouds and water vapour.
Geological evidence from studies of past climate change now suggests that if longer term factors are taken into account, such as the decay of large ice sheets and the operation of the full carbon cycle, the sensitivity of the Earth to a doubling of CO2 could be double that predicted by most climate models.
Read more at: http://phys.org/news/2013-12-earth-sensitivity-climate-previous-geologists.html#jCp