Figure 6-5: a) Radiative forcing components resulting
from the IS92a emission scenario for 1990 to 2100. The "Total Non-CO2 Trace
Gases" curve includes the radiative forcing from CH4 (including CH4-related
increases in stratospheric water vapor), N2O, tropospheric O3, and the halocarbons
(including the negative forcing effect of stratospheric O3 depletion). Halocarbon
emissions have been modified to take account of the Montreal Protocol and
its Adjustments and Amendments. The three aerosol components are direct sulfate,
indirect sulfate, and direct biomass burning.