Linear perturbation theory is applied to the problem of orographic and diabatic forcing with the intention of modelling the easterly flow of air over northern Australia. In an easterly, both orography and heating induce downstream waves whose wave-length increases with decreasing latitude, and increases as the strength of the flow increases. Upstream effects are evident far from the orography. The effects of heating differ from those of orography; heating induces both a far-upstream response and a permanent equatorwards displacement of the flow. The addition of the orographic effect to combined heating over the land and cooling to its west results in a two-ridge, two-trough streamline pattern over the continent which compares well with mean summertime conditions over northern Australia. In winter simulations with cooled land and warmed water, diabatic perturbation quantities are considerably smaller than their summer counterparts. Orographic effects dominate and result in the frequently observed east coast ridge and inland trough pattern.
M. Adams (Tue,) studied this question.