On Global Initialization of the Primitive Equations: Part I

Abstract

The problem of obtaining a realistic balanced relationship between the pressure field and the nondivergent velocity is examined for a global primitive equation model. Both a theoretical discussion of the atmospheric adjustment process and actual numerical examples of initialization are used to show that pressure at low latitudes must be the derived quantity and not the input data. For the two-layer version of the NCAR general circulation model, the latitudes of 27½N and S are shown to be acceptable for separating the equatorial belt, where velocity is used as input data, from regions of higher latitudes, where pressure is used as input data.