435
layer 2
Figure 11: Time mean streamfunction in the same numerical experiment as Figure (10).
Same isoline spacing.
manifested the momentum balance of the ACC as described in the introduction. In particular, the important role of the synoptic-scale eddies in
the transport of QPV and momentum has been pointed out. To make any
comparison between these eddy resolving experiments and the low-order
model we have to specify a representation of the eddy fluxes in the loworder model. We have chosen the simple linear interfacial friction as a
low-order image of the interfacial form stress caused by the eddies and neglected the Reynolds stress contribution. In view of the extensive research
on the topic of parameterizing QG eddies in the general atmospheric circulation (see e. g. the review of Hoskins 1983) our representation of the
downward momentum flux is very crude and can only be justified by the
simplicity of the model.
The constant friction parameter f.l was obtained by fitting the total
exchange of momentum by the eddies between the layers to the linear