Cyclostrophic balance

The lower boundary condition, u(zo), is the zonal wind speed at level zo- Elson (1979) has applied this diagnostic relation to the temperatures shown in Fig. 9.2.10. The lower boundary was taken to be at the cloud top height, zo = 65 km, and the wind speed, u(zo), was based on observed cloud motion. The resulting cyclostrophic component of the zonal wind in the northern hemisphere is shown in Fig. 9.2.11 as a function of latitude and z. At levels above the zero contour line pure cyclostrophic balance cannot hold since 94>/90 becomes positive. Other terms in Eq. (9.2.21) then become important in this part of the atmosphere. This result has led to the application of more complex diagnostic models by Taylor et al. (1980). 

Another example of an atmosphere in cyclostrophic balance is that of Titan. This case has been discussed in detail by Flasar et al. (1981), Hunten et al. (1984), and Flasar (1998) and is not pursued further. 

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