Another standard computation is to hold the SSTs and sea ice fixed and change
all radiative forcing agents from present day to pre-industrial values.
If radiative forcing were to be stabilised, keeping all
the radiative forcing agents constant at B1 or A1B levels in 2100, model experiments show that a further increase in global average temperature of about 0.5 °C would still be expected by 2200.
Radiative forcing as a result of increases in atmospheric CO2 concentrations caused by human activities since the preindustrial era predominates over all other
radiative forcing agents (IPCC, 2007a, SPM).