Abstract: Mathematical issues arising when applying four-dimensional variational (4DVAR) data assimilation to limited-area problems are studied. The derivation of the adjoint system for the initial-boundary value problem for a general ...

Abstract: The impact of discontinuous model forcing on the initial conditions obtained from 4DVAR data assimilation is studied with mathematic analyses, idealized numerical examples, and more realistic meteorological cases. The ...

Abstract: The accuracy of finite-diffrerence approximations to the shallow water equations on a sphere is examined for flow cases having an analytic solution. Approximations over grids with the longitudinal grid increment (??) ...

Abstract: The Limited-Area Model (LAM) developed at the National Center for Atmospheric Research for use in conjunction with the NCAR Global Circulation Model is described including details of the lateral boundary conditions. One ...

Abstract: Three-dimensional variational data assimilation (3DVAR) analysis is an important method used at many operational and research institutes in meteorology, for example, the National Centers for Environmental Prediction (NCEP) ...

Abstract: The convergence of spectral model numerical solutions of the global shallow-water equations is examined as a function of the time step and the spectral truncation. The contributions to the errors due to the spatial and ...