\documentstyle[12pt,agu_abstract]{article} \begin{document} \begin{abstract}{Data Assimilation into Nonlinear Stochastic Ocean Models }{ \underline{Everett F. Carter Jr}, (Department of Oceanography, Code OC/CR Naval Postgraduate School, Monterey, CA, 93943; 831-656-3318), {Robert N. Miller},{Sally B. Goodlett}, (College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis OR, 97331; 503-737-4555) }{ We consider the problem of data assimilation into systems modeled as nonlinear stochastic differential equations. Unlike earlier approaches to this problem, we calculate a direct estimate of the probability density function of the system conditioned on the observations. No assumptions about moments or near-linearity are required. We present a series of simulation experiments in which we demonstrate assimilation of data into simple nonlinear models where the (Extended) Kalman filter will not perform well. We illustrate the basic method with a simple one dimensional nonlinear stochastic differential equation, a three-dimensional caricature of the ENSO cycle and a nonlinear quasigeostrophic channel model. } \item 1993 Fall Meeting \item 000121505 \item (a) E. F. Carter \\ Dept. Oceanography, OC/CR \\ Naval Postgraduate School \\ Monterey, CA 93943 \\ (b) Tel: (831) 656-3318 \\ (c) FAX: (831) 656-2712 \item O (Ocean Sciences) \item (a) none \\ (b) 4263, 4255, 4520 \\ (Ocean Prediction, \\ Numerical Modeling, \\ Eddies and mesoscale processes) \\ (c) none \item Poster, Video \item 0\% \item \$60 charge to:\\ Mastercard XXXX XXXX XXXX XXXX\\ expires X/XX \item C (Contributed) \item None \item No \end{abstract} \end{document}