Adjoint Sensitivity Analysis Applied to the Adaptive Location of the Observations

The spatial-temporal distribution of the observations plays an essential role in the data assimilation process. Strategies for the adaptive location of the observational system search for locations in space and time where additional observational resources should be deployed in order to minimize the forecast error. In this paper we present an application of the adjoint sensitivity analysis to the problem of adaptive location of the observational system and area targeting for a transport-chemistry model in the context of 4D variational data assimilation. Numerical experiments are presented for a two-dimensional test model.