ROMS Application into Pacific Ocean and US West Coast at JPL

1
ROMS Application into Pacific Ocean and US West
Coast at JPL
Carrie Zhang and the JPL ROMS Group Yi Chao, Jei
Choi, Peggy Li, Zhijin Li, Xiaochun Wang Jet
Propulsion Laboratory, California Institute of
Technology, Pasadena, California Collaborators
James McWilliams, Changming Dong, Meinte Blass,
Nicolas Gruber, Alexander Shchepetkin, Capet
Xavier Institute of Geophysics and Planetary
Physics, University of California at Los Angeles,
California Fei Chai, University of Maine
I. Introduction The JPL ROMS group, in
collaboration with the UCLA ROMS group, has
developed a number of ROMS configurations ranging
from Pacific Ocean basin-scale to U.S. west
coast. Recently, an advanced data assimilation
scheme based on the 3-dimensional variational
method (3DVAR) is implemented in ROMS. In
collaboration with University of Maine, a coupled
physical-biological model is also developed.
During August 2003, the ROMS and the associated
data assimilation system have been tested in a
real-time field experiment making nowcast and
forecast every 24 hours. Extensive model
validations have been conducted. It is expected
that both the Pacific Ocean and U.S. west coast
ROMS will be in real-time operations in the
coming years.
III. Central California Coastal Ocean Monterey
Bay Three-level online embedded ROMS (using AMR)
is applied to study the physical processes in the
Monterey Bay (15km-gt5km-gt1.5km). An end-to-end
database is also developed for real-time data
processing, modeling, data assimilation, and
operational forecasting. This end-to-end system
has been tested during a 1-month long field
experiment in August 2003.
II. Pacific Ocean The current Pacific Ocean
model is based on the MPI ROMS version and has a
spatial resolution of 50-km and 30 vertical
layers. After 100 years spinup forced with
monthly climatological air-sea fluxes, a 50-year
(1950-2000) simulation has been made forced by
daily NCEP-NCAR reanalysis.
Pacific 50-km ROMS Simulated SSS Variability in
the tropical Pacific (Wang and Chao, GRL, 2004)
Monterey Bay 1.5-km ROMS Validating ROMS
assimilation results against independent mooring
observations
Monterey Bay 1.5-km ROMS Initial results from
coupled physical-biological model simulations
Simulating El Nino-Southern Oscillation
Simulating Pacific Decadal Oscillation (PDO)
IV. Southern California Coastal Ocean Four-level
online embedded ROMS (using AGRIF) has been
developed to study the physical and biological
processes in the Southern California Bight
(20km-gt6.7km-gt2.1km-gt0.75km).
SUMMARY We plan to improve the ROMS
configurations off the California coast and
transition our real-time demonstration to routine
operations making real-time nowcast and forecast
for the California coastal ocean. An
eddy-permitting ROMS configuration has been
developed for the Pacific Ocean at 12.5-km
resolution (1520x1088x30) using the MPI code. We
are currently spinup this model using the
climatological flux on the SGI Altix computer
with 128 processes. The results from this high
resolution Pacific basin-wide ROMS simulation
will be used to study the mesoscale eddy
variability and eddy-mean flow interactions as
well as to provide the needed boundary conditions
for regional ROMS configurations. A regional ROMS
configuration for the Prince William Sound in
Alaska is currently under construction.