Zhou, Chunhua, Hui Shao, National Center for
Atmospheric Research, Ming Hu, Ligia Bernardet, NOAA/ESRL, Xiang-Yu Huang and
Brian Etherton, NCAR
Hybrid 3DVAR
incorporates flow-dependent information from the ensemble perturbations into
the static background error covariances used in 3DVAR, and has been shown to
have positive impact on global forecasts and some regional applications. In
this study, GSI (Gridpoint Statistical Interpolation) - Hybrid is being tested
for the HWRF (WRF for Hurricanes) system. A case study is performed for Bret
2011 and positive impact from the GSI-Hybrid data assimilation is shown for the
hurricane forecast, especially with the track forecast, in comparison with pure
GSI 3DVAR applied for HWRF. Further studies are being conducted to assess the
impact of satellite radiance data in the framework of GSI-Hybrid and
preliminary results will be presented.