Ground-Based Remote Sensing of Cloud Properties ...
363
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Figure 13.23: (a) Cloud drop number density nmg(D) (dashed line) and reflectivity density
S;(D) (solid line) for gamma distribution parameters Nt = 6.5 x 10 6 m- 3 , Dn = 0.233 mm
and v = 1. (b) Reflectivity density versus drop fall velocity for no turbulence (upper dashed
line), turbulence with v" = w" = 0.4 (lower dashed line) and turbulence with v" = w" = O.B
(solid line). Positive velocities are downward. (c) Reflectivity density S!(D) that results from
changing variables in S; ( v) from drop fall velocity v to drop diameter D.
If one simply changes variables in S!(v) from v to D, Le.,
S;(D) = S!(v(D)) :~(D),
(13.108)