A New Method for Vertical Interpolation of the Mass Field

Abstract

A new method for vertical interpolation of the mass field, starting from data on standard p levels, has been devised. The method extracts information about vertical temperature profiles from geopotential values on these levels, thus recovering part of the relevant details about atmospheric thermal stratification that get lost in this widely used type of representation. Through the proposed procedure, a vertical temperature profile with a piece-wise linear dependence on height is obtained. It conserves original geopotential thicknesses while maintaining the initial temperature values on standards p levels. By statistically comparing the method with usual interpolations of T and ?, it is shown that the proposed method provides a clearly better reproduction of internal and potential energy of atmospheric columns. This feature may be important, for example, in the assignment of initial and boundary values for numerical simulations, where a correct model reproduction of thermal stratification is essential.