IGPP is pleased to invite you to join its Spring 2024 Seminar Series presentation featuring University of Arizona's Shay Gilpin. Dr. Gilpin's talk, "A New Parametric Correlation Function for Geophysical Data Assimilation Applications" will occur at 3pm WEDNESDAY April 17, 2024.
Time: 3:00pm, Pacific Time
Location: MUNK Conference Room
Abstract: Parametric correlation functions play an essential role in various geophysical problems, for example to model error covariances for uncertainty quantification, to construct symmetric positive definite matrices for regularized inverse problems, or to apply as tapering functions to localize covariances in ensemble-based data assimilation schemes. In this seminar, I will introduce a new, generalized version of the widely used Gaspari-Cohn correlation function. This new function, which I refer to as the Generalized Gaspari-Cohn (GenGC), allows both its parameters a and c to vary, as functions, whereas the Gaspari-Cohn correlation function is limited to fixed parameters a and c. As a result, GenGC is able to construct correlations that can be informed by physical considerations, producing interesting, physically-relevant features that the original Gaspari-Cohn correlation function cannot. I will describe the chemical constituent transport problem that motivated my derivation of GenGC, present two examples of GenGC applied to geophysical data assimilation, and conclude with remarks on how GenGC can be used in other geophysical applications.