the RCP8.5 scenario from 1979 to 2100—the CMIP5 members were selected as representative of a
range of outcomes for future climate change, including high and low climate sensitivity, different
biases in baseline precipitation climatology, and different global patterns of precipitation change.
Speciﬁc levels of global warming such as 1.5°C or 2°C were deﬁned on the basis of the global
mean temperature in the original CMIP5 projections. The time of reaching a speciﬁc level of global
warming, therefore, varied between ensemble members. The CMIP5 SSTs were not bias-corrected,
which means that the results here may be sensitive to systematic errors arising from biases in the
present-day SST patterns.
Atmospheric greenhouse gas concentrations were prescribed from the standard RCP8.5
concentration scenario. Aerosol concentrations were calculated within the model, with aerosol
emissions prescribed again from the standard RCP8.5 scenario. This means that the greenhouse
gas and aerosol concentrations, and hence radiative forcing, were the same in all ensemble