Figure 6-14: Bar charts of radiative forcing
from (a) all perturbations in 1990 (from IPCC, 1996) and (b) aviation effects
in 1992. Note scale change from (a) to (b). In (b), best estimate (bars) and
high-low 67% probability intervals (whiskers) are given. No best estimate
is shown for the cirrus clouds; rather, the dashed line indicates a range
of possible estimates. The evaluations below the graph are relative appraisals
of the level of scientific understanding associated with each component.