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Zou., X. A., A. Barcilon, I. M. Navon, J. S. Whitaker, and D. G. Cacuci, 1993: An adjoint sensitivity study of blocking in a two-layer isentropic model. Mon. Wea. Rev., 121, 2834-2857.

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An adjoint sensitivity study of blocking in a two-layer isentropic model

X. Zou

Supercomputer Computations Research Institute, The Florida State University, Tallahassee, FL

Albert Barcilon

Dept. of Meteorology and Geophysical Fluid Dynamics Institute, The Florida State University, Tallahassee, FL

I. M. Navon

Department of Mathematics and Supercomputer Computations Research Institute, The Florida State University, Tallahassee, FL

Jeffrey S. Whitaker

CIRES, University of Colorado, Boulder, CO

D. G. Cacuci

Department of Nuclear Engineering, University of Illinois, Urbana, IL

Abstract

This paper presents a new methodology for adjoint sensitivity analysis, previously described in general terms by Cacuci, into a form directly applicable to meteorological problems. This technique is illustrated by examining the sensitivity of a blocking index in a two-layer isentropic model. This index represents a response function for the sensitivity analysis that, unlike previous meteorological applications, is an operator and not a functional, and thus, extends the scope of adjoint sensitivity to general operator-type responses depending on time and/or space.

The sensitivity of the blocking index to perturbations introduced into the model atmosphere, as well as to model parameters, is discussed. The methodology of generalized adjoint sensitivity analysis described in this paper constitutes a prototype for further applications in the atmospheric and/or oceanic sciences.