204
J. C. W Y N U A A K I ) ET AL.
5.3. Sopiti & [ ) i ~ r , s of Geosrrophic M'incl Slierrr
rcctstngiilar profiles:
To investigate the effect of z-dependent geostrophic wind, we used simple
Confining the geostrophlc shear to a finite layer assures that the flow above
will approach a uniform free stream so thc usual upper boundary conditions
can be used. Figure 7 shows calculated uw distributions for the four combinations in (28). Although thc imposcd shear is not large (it corresponds to
I m/wc change in U, and r/, over 1 km depth at 45' latitude), the stress
profiles are severely distorted.
I 1 I l l l l l 1 -
- 10,lO -
***.* 10,-10
-.- -10,-10 -
0,o
1.2 -
1 . 1
- 0 -
-10,lO
-
-
1.0 -
9 -
.8
-
i'
/' \
-
-
D
.
a
/
-
l f
. 7 -
4
4
-
0
I
4
/
'* 6 -
/
5 -
I
I
\
4 -
\
. 3
\
. 2 -
, I -
0'
-
*.
\
' ' ' I
1.0 . e .6 .4 . 2 0 -.2 -.4 -.6 -.8 - I 0
-
" W / ":
I I G . 7. TheelTcct ofgcostrophic wind shcur on the neutral U T profile. for four cornhinations
or ( I' cl;u,f':,j 1 x,vZ).
6. STEADY-STATE UNSTABLE STRUCT~JRE
By letting the surface heat flux Qo be positive. we generate, with the same
model set. un unstable planetary boundary layer. We found, as did Deardorll: the1 for all but very weakly unstable conditions the convective layer