HR: 1330h
AN: OS42A-0825 [PDF]
TI: A three-dimensional variational data assimilation system
for coastal oceans
AU: * Li, Z
EM: zhijin.li@jpl.nasa.gov
AF: Jet Propulsion Laboratory, M/S 300-323, Jet Propulsion Laboratory, California Institute of Technology,
4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Chao, Y
EM: yi.chao@jpl.nasa.gov
AF: Jet Propulsion Laboratory, M/S 300-323, Jet Propulsion Laboratory, California Institute of Technology,
4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: McWilliams, J
EM: jcm@atmos.ucla.edu
AF: University of California at Los Angeles, 405 Hilgard Ave.,Los Angeles CA 90095-1567, Los Angeles, CA
90095-1567 United States
AB:
A three-dimensional variational data assimilation system (3DVAR) has been developed in association with the Regional Oceanic
Modeling System (ROMS) and implemented in a real-time forecasting system for the U. S. West Coastal region. This 3DVAR
system assimilates sea surface temperature (SST) and along track sea surface heights (SSH) from multiple satellites, as well
as a variety of autonomous underwater vehicle (AUV) and in situ measurements. The real-time implementation of this 3DVAR has
shown satisfactory performance in terms of results, reliability, and efficiency.
Several particular strategies are implemented in this 3DVAR. A new strategy for incorporating three-dimensional error
self-covariances and cross-covariance is developed that allows us to cope with strongly inhomogeneous and anisotropic error
covariances in coastal oceans. Since the quality of many remotely sensed measurements deteriorates approaching the coastline,
the 3DVAR is further implemented with constraints in geostrophic and hydrostatic balances to control the dynamical behavior
of the analysis increment. This 3DVAR system has been programmed with both OpenMP and MPI parallelism. A limited-memory,
quasi-Newton, minimization algorithm with preconditioning is employed to accelerate the convergence towards optimization.
UR: http://ourocean.jpl.nasa.gov
DE: 4842 Modeling
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting