East Asia and Western Pacific METEOROLOGY AND CLIMATE

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where N is nondimensional Newtonian cooling coefficient, S
measures mean static stability of the basic state; I and B
represent ratios of latent heating to adiabatic cooling due
to vertical motion at P2 and p e/ respectively. We have used
c 0 / (c 0 /B) 1/2 , (6c 0 )~ 1/2 , GO, and 2Ap(Bc 0 ) 1/2 as horizontal
velocity, length, time, geopotential, and vertical p-
velocity scales, respectively, where c 0 is long gravity wave
speed in 2-level model.
The boundary layer friction-induced vertical velocity
OJ e can be expressed in terms of geopotential at p e and 0 e
(Wang and Chen, 1988):
^2 A S (E 2 + 2 ) ^"^271^EVy a x)
where E=p e gAz/ [ (p s -p e ) /Bc 0 -h- In(h/z 0 ) ] is the Ekman number
determined by turbulent viscosity A z , depth of the surface
layer h, the surface roughness length z 0 and density p c .
The upper boundary and lateral boundary conditions are
c