Laterally-Driven Stochastic Motions in the Tropics

A two-layer model is used to 'investigate the asymmetric motions in the tropical atmosphere as small perturbations on a symmetric basic. state which contains a vertical shear in the zonal wind. The physics used to describe them ignore latent heat, but include parameterized dissipation and non-geostrophic effects. The perturbed motion is treated as stationary random process driven by forcing at lateral boundaries located at 30 N and 30 S. The forcing motions are prescribed statistic-ally in terms of spectra determined from 23 months of data at 300N, and with the assumption that the forcing at the two boundaries are statis-tically independent but otherwise are statistically similar. The mathematical problem is to express second moment statistics of the internal motions in terms of the basic state parameters and the boundary statistics. This can be resolved into two separate steps: (1) to construct the response functions of the statistics from the fun