Scientists measure the sensitivity of the Earths climate to greenhouse gases by estimating the temperature rise that would be caused by a doubling of CO2 in the atmosphere compared with pre-industrial levels  as is likely to happen within 50 years, on current trends.

Scientists measure the sensitivity of the Earths climate to greenhouse gases by estimating the temperature rise that would be caused by a doubling of CO2 in the atmosphere compared with pre-industrial levels  which is likely to happen within 50 years.
