Effect of random perturbations on adaptive observation techniques
نویسندگان
چکیده
An observation sensitivity method to identify targeted observations is implemented in the context of four dimensional variational (4D-Var) data assimilation. This methodology is compared with the well-established adjoint sensitivity method using a nonlinear Burgers equation as a test model. Automatic differentiation software is used to implement the first order adjoint model to calculate the gradient of the cost function required the 4D-Var minimization algorithm and adjoint sensitivity computations and the second order adjoint model to obtain the Hessian matrix of the 4D-Var cost required in the observation sensitivity computations. Numerical results indicate that the observation-
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