1520-0469%282016%29058%3C2073%3Aadatff%3E2%2E0%2Eco%3B2.pdf

1 AUGUST 2001 O O Y A M A 2073 A Dynamic and Thermodynamic Foundation for Modeling the Moist Atmosphere with Parameterized Microphysics KATSUYUKI V. OOYAMA Hurricane Research Division, AOML, NOAA, Miami, Florida (Manuscript received 14 March 2000, in final form 2 November 2000) ABSTRACT Moist convection is an exquisite yet powerful participant in the creation of weather on our planet. To facilitate numerical modeling of weather systems in a moist atmosphere, a direct and consistent application of dynamic and thermodynamic principles, in conjunction with parameterized microphysics, is proposed. An earlier for- mulation of reversible thermodynamics, in terms of the mass of air and water substance and the total entropy, is now extended to include the irreversible process of precipitation through parameterized microphysics. The dynamic equations are also formulated to account consistently for the mass and momentum of precipitation. The theoretical proposal is tested with a two-dimensional model that utilizes a versatile and accurate spectral method based on a cubic-spline representation of the spatial fields. In order to allow a wide range of scale interactions, the model is configured on multiply nested domains of outwardly decreasing resolution, with noise- free, two-way interfaces. The semi-implicit method provides efficient time integration for the nested spectral model.