HR: 18:05h
AN: A24B-08 [Abstracts]
TI: Applications of bred vectors in NASA GMAO ocean assimilation system
AU: * Yang, S
EM: scyang@atmos.umd.edu
AF: Global Modeling and Assimilation Office, NASA, 8800 Greenbelt Road, Greenbelt, MD
20771, United States
AU: * Yang, S
EM: scyang@atmos.umd.edu
AF: Earth System Science Interdisciplinary Center / University of Maryland, 2207 CSS BLDG,
University of Maryland, College Park, MD 20742, United States
AU: * Yang, S
EM: scyang@atmos.umd.edu
AF: Department of Atmospheric and Oceanic Science, University of Maryland, Department of
Atmospheric and Oceanic Science
University of Maryland, College Park, MD 20942, United States
AU: Keppenne, C L
EM: clk@gmao.gsfc.nasa.gov
AF: Global Modeling and Assimilation Office, NASA, 8800 Greenbelt Road, Greenbelt, MD
20771, United States
AU: Rienecker, M
EM: Michele.Rienecker@nasa.gov
AF: Global Modeling and Assimilation Office, NASA, 8800 Greenbelt Road, Greenbelt, MD
20771, United States
AU: Kalnay, E
EM: ekalnay@atmos.umd.edu
AF: Department of Atmospheric and Oceanic Science, University of Maryland, Department of
Atmospheric and Oceanic Science
University of Maryland, College Park, MD 20942, United States
AB:
Bred vectors (BV) are generated for the use of initial ensemble perturbations for NASA GMAO coupled ensemble
forecasting system (GCEF) and for the purpose of improving the ensemble prediction of seasonal-to-interannual
variability. Currently, four pairs of BVs are generated with different rescaling norms and with one-month rescaling
period with GCEF. In this study, we explore the applications and potential impact of the oceanic component of the
bred vectors in NASA GMAO oceanic data assimilation system.
BVs are applied as a shortcut to provide the structures of flow-dependent background error covariance and used
to augment the background error covariance in the assimilation system (the optimal interpolation scheme). In this
hybrid assimilation framework, the error correlation is modified to have seasonal and regional-dependent
structures. Our preliminary results suggest that BVs have positive impact on the local structures of the corrections
for both temperature and salinity fields. Other issues of utilizing the BV structures in the assimilation system will
be addressed in the talk.
DE: 3315 Data assimilation
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly