HR: 0800h
AN: A31B-03 [Abstracts]
TI: Assimilation of Temperature, Salinity, and Sea Surface Height Data into the GMAO Ensemble Kalman Filter and its Impact on Seasonal Hindcast Skill
AU: * Kovach, R
EM: kovach@gmao.gsfc.nasa.gov
AF: Science Applications International Corporation, 10260 Campus Point Dr., San Diego, CA
92121, United States
AU: Keppenne, C
EM: clk@gmao.gsfc.nasa.gov
AF: Science Applications International Corporation, 10260 Campus Point Dr., San Diego, CA
92121, United States
AU: Rienecker, M
EM: Michele.Rienecker@nasa.agov
AF: Global Modeling and Assimilation Office, Code 310.1
NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Marshak, J
EM: Jelena.Marshak@nasa.gov
AF: Global Modeling and Assimilation Office, Code 310.1
NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Jacob, J
EM: jjacob@gmao.gsfc.nasa.gov
AF: Science Applications International Corporation, 10260 Campus Point Dr., San Diego, CA
92121, United States
AB:
A multivariate ensemble Kalman filter (EnKF) is used to assimilate in situ temperature and salinity observations
and remotely sensed altimeter data into a global OGCM. To evaluate the impact of the state-dependent
multivariate covariances from the EnKF, the EnKF sub-surface analysis fields for temperature, salinity, and zonal
velocity are compared to the GMAO production ocean analysis obtained with a) temperature optimal interpolation
(OI-T) complemented with a salinity correction to preserve the (T,S) relationship, and b) temperature and salinity
optimal interpolation (OI-TS) where Argo salinity and synthetic salinity from TAO, XBT, and Pirata are assimilated.
Observations from TAO, Pirata, and Argo, and independent data from ADCPs, and CTDs are used to validate the
analyses.
The ensemble of ocean states is then used to initialize the ocean model used in the GMAO coupled forecasting
system. Three experiments are performed to evaluate the impact of different observing systems on hindcast skill.
-Exp1 uses the following data:
Temperature profiles from TAO, Pirata, Argo, and XBTs
Salinity profiles from Argo
Synthetic salinity observations estimated from temperature profiles and climatological T-S relations
Sea surface height anomalies from Topex and Jason altimeter data
-Exp2 excludes the salinity data from Argo
-Exp3 excludes the altimeter data
The hindcast skill of the forecast system initialized with the EnKF is compared to that of the production forecasting
system in which univariate optimal interpolation (OI) is used to initialize the OGCM prior to coupling. Hindcast
skill for sea surface temperature and sea surface height in the equatorial Pacific Nino regions are assessed.
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 4260 Ocean data assimilation and reanalysis (3225)
DE: 4262 Ocean observing systems
DE: 4522 ENSO (4922)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly