«We use 1280 years of control simulation, with constant preindustrial forcings including constant specified CO2, and a five - member ensemble of historical simulations from 1850 — 2005 including
prescribed historical greenhouse gas
concentrations, SO2 and other
aerosol - precursor emissions, land use changes, solar irradiance changes, tropospheric and stratospheric ozone changes, and volcanic
aerosol (ALL), following the recommended CMIP5 specifications.
«Reducing the wide range of uncertainty inherent in current model predictions of global climate change will require major advances in understanding and modeling of both (1) the factors that determine atmospheric
concentrations of greenhouse gases and
aerosols, and (2) the so - called «feedbacks» that determine the sensitivity of the climate system to a
prescribed increase in greenhouse gases.»