Bayesian Hierarchical Models


Collaborators:
Dr. Ralph F. Milliff
Colorado Research Associates Division (CoRA),
NorthWest Research Associates, Inc.
milliff@cora.nwra.com
Professor L. Mark Berliner
Department of Statistics
Ohio State University
mb@stat.ohio-state.edu
Professor Nadia Pinardi
Corso di Scienze Ambientali
University of Bologna
n.pinardi@sincem.unibo.it
Professor Christopher K. Wikle
Department of Statistics
University of Missouri
wikle@stat.missouri.edu
Professor Emanuele Di Lorenzo
School of Earth and Atmospheric Sciences
Georgia Institute of Technology
311 Ferst Drive, Atlanta, GA 30332
edl@gatech.edu
 

ABSTRACT:
Bayesian Hierarchical Models (BHM) are implemented to establish ensemble ocean forecasting tools for the Mediterranean Forecast System (MFS). Progress is reported for MFS-Wind-BHM and MFS-Error-BHM from Phase I of the research. Ocean ensemble initial conditions and ensemble forecasts driven by MFS-Wind-BHM exhibit distributions of ocean circulation uncertainty concentrated in mesoscale features. Plans for MFS-Error-BHM are described to refine vertical error covariance estimates, and build daily time-dependence in background error covariance for MFS reduced-order optimal interpolation. Research plans for Phase II are proposed to focus on extending skill in targeted ocean forecasts using BHM methodology for superensemble forecast implementations. Med-MultiModel-BHM is a superensemble forecast system that will include contributions from a proposed Mediterranean implementation of the Regional Ocean Modelling System (ROMS) to combine with MFS forecasts. Two variants of an MFS-MultiParam-BHM methodology are described. In one, a superensemble is constructed of MFS models employing different vertical mixing parameterizations. In a second variant, a superensemble using different model resolutions will be constructed. Large ensemble sizes from coarse resolution MFS models can combine with high-resolution MFS implementations to yield an optimal superensemble forecast. We propose to explore the accumulating impacts of BHM on MFS using stochastic optimal/non-normal operator diagnostics.
 

             ©2008