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Sim D. Aberson

(GFS and GFDL) and upgrades to them during the 10-yr period are provided in the next section. An in-depth assessment of the impacts from the surveillance missions on model track and intensity forecasts are provided in section 3 . Since the initial and boundary conditions for the GFDL are largely based on the GFS, the results of the two models are compared in section 4 . Section 5 has a description of the relationship between GFDL track and intensity forecast improvements because of surveillance

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Ryan D. Torn and Gregory J. Hakim

scheme ( Kain and Fritsch 1990 ), Yonsei University (YSU) boundary layer scheme ( Hong et al. 2006 ), and the Noah land surface model ( Ek et al. 2003 ). An ensemble of lateral boundary conditions for the outer domain is obtained using the fixed-covariance perturbation (FCP) technique of Torn et al. (2006) . Ensemble lateral boundary conditions are derived by drawing random perturbations from the WRF VAR system ( Barker et al. 2004 ), which are scaled by 1.7, and subject to a temporal

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Fuqing Zhang, Yonghui Weng, Jason A. Sippel, Zhiyong Meng, and Craig H. Bishop

parameterization schemes include the Grell–Devenyi cumulus scheme ( Grell and Devenyi 2002 ), WRF single-moment six-class microphysics with graupel ( Hong et al. 2004 ), and the Yonsei State University (YSU) scheme ( Noh et al. 2003 ) for planetary boundary layer processes. The NCEP GFS operational analysis at 0000 UTC 12 September and its forecast are used to create the initial and boundary conditions. Data assimilation is performed for all domains but all verification is performed for D3. b. The data

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Peter Black, Lee Harrison, Mark Beaubien, Robert Bluth, Roy Woods, Andrew Penny, Robert W. Smith, and James D. Doyle

index (RII; DeMaria and Kaplan 1999 ; DeMaria et al. 2005 ; Knaff et al. 2005 ; Jones et al. 2006 ; DeMaria 2009 , 2010 ; Kaplan et al. 2010 ). These models stand to benefit from improved model and observational spatial and temporal resolution. Enhanced model resolution of smaller-scale physical processes, such as convective events, boundary layer air–sea transfer processes, and upper-troposphere outflow jets, will likely benefit to a greater degree from observational inputs at commensurate

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Hyun Mee Kim and Byoung-Joo Jung

, 133°E), with a 100-km horizontal resolution and 14 evenly spaced sigma levels in the vertical from the surface to 50 hPa. The model’s initial and lateral boundary conditions are taken from the National Centers for Environmental Prediction (NCEP) final analysis (FNL; 1° × 1° global grid). Physical parameterizations used in the simulation include the Grell convective scheme, a bulk aerodynamic formulation of the planetary boundary layer, the simple cooling radiation scheme, horizontal and vertical

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Chun-Chieh Wu, Shin-Gan Chen, Jan-Huey Chen, Kun-Hsuan Chou, and Po-Hsiung Lin

1. Introduction Conventional observational data are inadequate in providing accurate initial and boundary conditions for numerical model simulations and forecasts of tropical cyclones (TCs), thus often leading to poor track and intensity forecasts ( Wu and Kuo 1999 ; Wu et al. 2005 ). Therefore, making additional observations in the critical areas that will have the maximum influence on numerical forecasts of TCs is an important task. Operational aircraft surveillance missions have been

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Shin-Gan Chen, Chun-Chieh Wu, Jan-Huey Chen, and Kun-Hsuan Chou

vertical. The initial and boundary conditions are acquired from the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) analysis, which has a horizontal resolution of 1° × 1°. 3. Results a. ADSSV sensitivity and initial perturbation fields Since the sensitivity of Shanshan’s motion to the synoptic systems from the ADSSV perspective has been investigated, ADSSV sensitivity of the case conducted in this paper is briefly reviewed here. The ADSSV [throughout the paper, only

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Mu Mu, Feifan Zhou, and Hongli Wang

), and corresponding adjoint model ( Zou et al. 1997 ). The following physical parameterizations are used: dry convective adjustment, grid-resolved large-scale precipitation, the high-resolution PBL scheme, and the Kuo cumulus parameterization scheme. The initial and boundary conditions are from the National Centers for Environment Prediction (NCEP) Global Forecasting Systems (GFS) global reanalysis (1° × 1°) interpolated to the MM5 grids. The horizontal resolution is 60 km, and the vertical range is

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