Accession Number : AD0691763

Title :   NUMERICAL EXPERIMENTS WITH HIGH-ORDER ADVECTIVE EQUATIONS.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CALIF

Personal Author(s) : Morford,Dean Russell

Report Date : DEC 1968

Pagination or Media Count : 58

Abstract : Second-order and fourth-order two-dimensional advective equations developed by W. P. Crowley were examined to determine their applicability to atmospheric models. One second-order and two fourth-order forms were evaluated from their performances on a simple pattern advected by a linear, divergent velocity field. The same equations were substituted for the advection term of a simple barotropic forecast model to determine their performances on more general non-linear conditions. All forms of the equations remained stable in time and demonstrated the phase and amplitude characteristics predicted by Crowley. The fourth-order 'advection' form gave best results. When substituted in the barotropic model, the fourth-order forms lead to improved trough and low-center movements, but RMSE was slightly larger than that resulting from second-order forms. The better RMSE of the lower order forms apparently resulted from their diffusive characteristics. (Author)

Descriptors :   (*ATMOSPHERIC MOTION, NUMERICAL ANALYSIS), CONVECTION(ATMOSPHERIC), ATMOSPHERE MODELS, PARTIAL DIFFERENTIAL EQUATIONS, DIFFERENCE EQUATIONS, PERTURBATION THEORY, WEATHER FORECASTING, AIR MASS ANALYSIS, COMPUTER PROGRAMMING, AIR POLLUTION, FALLOUT, THESES

Subject Categories : Atmospheric Physics
      Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE