A new technique of physical dissipation and its application to a mesoscale numerical weather prediction model

In terms of statistical physics, a fluid such as the atmosphere is a many-body system which has a vast amount of degree of freedom and thus obeys the second law of thermodynamics.In this paper, a noticeable improvement of the prognostic outputs is made by reconstructing the terms of the horizontal diffusion of MM5 according to the principles of the second law of thermodynamics; besides, the computational noise is effectively and significantly suppressed since the physical dissipative technique for reconstructing suggested in this paper is based on the physical law rather than on the computational method such as the artificial viscosity.