443Climate Engineering: Impact Reducer or Suffering Inducer?
at the surface, the hydrological cycle would be less likely to be adversely
impacted. A comprehensive comparison to other approaches has not yet,
however, been conducted.
12.4.5 Proposed Approaches for Increasing the
Reflectivity of the Surface
Proposals to increase the surface albedo as a means to reduce the amount
of absorbed solar radiation go back to the mid-twentieth century (e.g., PSAC
1965), but most approaches seem to have a very limited potential. Roughly
50% of incoming surface radiation makes it through the clouds, ozone, and
water vapor to be absorbed at the surface, with an additional 5% being
reected from the surface back out to space as a result of a surface albed ...