Atmospheric and Oceanic Sciences Seminar

Generalized hybrid coordinates have been implemented into NCEP GFS with options of sigma, sigma-pressure and sigma-theta (as isentropic coordinates) under the same model numerics and physics. One-year parallel weather forecasts with sigma-theta coordinates resulted in encouraging statistical scores, with improvements over tropical areas and hurricane predictions. Operational concerns are discussed with further development of considering mass conserving semi-Lagrangian advection.