IMPORTANT LITERATURE ON THE USE OF ADJOINT, VARIATIONAL-METHODS AND THE KALMAN FILTER IN METEOROLOGY

The use of adjoint equations is proving to be invaluable in many areas of meteorological research. Unlike a forecast model which describes t he evolution of meteorological Fields forward in time, the adjoint equ ations describe the evolution of sensitivity (to initial, boundary and parametric conditions) backward in time. Essentially, by utilizing th is sensitivity information, many types of problems can be solved more efficiently than in the past, including variational data assimilation, parameter fitting, optimal instability and sensitivity analysis in ge neral. For this reason, the adjoints of various models and their appli cations have been appearing more and more frequently in meteorological research. This paper is a bibliography in chronological order of publ ished works in meteorology dealing with adjoints which have appeared p rior to this issue of Tellus. Also included are meteorological works r egarding variational methods (even without adjoints) and Kalman filter ing in data assimilation, plus some references outside meteorology. Th ese additional works are included here because the main thrust for adj oint application within meteorology is currently concentrated in the d evelopment of next-generation data assimilation systems.