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Katherine A. Pingree-Shippee, Norman J. Shippee, and David E. Atkinson

useful in this regard because the source code is available and it has a well-established validation track record. Previous validation efforts that have included the Alaska region (in particular, the Bering Sea and the Gulf of Alaska) indicate that modeled significant wave heights are generally underestimated ( Chawla et al. 2009 , 2011 ; Spindler and Tolman 2010 ; Stopa and Cheung 2014 ). These studies consist of climatological evaluations of the wave states, they do not perform analyses on a

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Guifu Zhang, Richard J. Doviak, Dusan S. Zrnić, Robert Palmer, Lei Lei, and Yasser Al-Rashid

beneficial feature. In section 2 the meteorological measurements with a PPPAR are simulated and the PPPAR’s deficiencies are revealed. In section 3 , a cylindrical array configuration is described and the CPPAR performance is quantified through a theoretical analysis and simulation. An example design and simulation results are given in section 4 . Summary and discussions are provided in the last section. 2. Issues with a PPPAR For a PPPAR, three or four faces are normally used to cover the 360° in

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Christopher R. Jackson

times 1.415 and 2.492 being generated closer to the time of the westward current extrema. 7. Summary This paper describes the development and performance of a new approach for estimating the geographic location of nonlinear internal wavefronts. The approach makes use of the wave signatures recorded in satellite imagery and a parameterized model function to determine a two-dimensional phase speed map and calculate a propagation time to locations over the region of interest. Contours of the

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Mark L. Morrissey, Werner E. Cook, and J. Scott Greene

1. Introduction The wind power density (WPD) is required for the estimation of power potential from wind turbines. It is a nonlinear function of the wind speed probability density function (PDF). The wind speed PDF is usually estimated from data and then used as a functional in the WPD distribution function, which can be integrated to obtain the WPD (e.g., Çelik 2003a ). The wind speed PDF has traditionally been estimated using a parametric model applied to wind speed data at turbine height

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Yong Chen, Fuzhong Weng, Yong Han, and Quanhua Liu

1. Introduction The development of fast and accurate thermal infrared (IR) radiative transfer (RT) models for clear atmospheric conditions has enabled the direct assimilation of satellite-based radiance measurements in numerical weather prediction (NWP) models. Most fast RT models are based on fixed transmittance coefficients that relate atmospheric conditions to optical properties. One such fast RT model is the Community Radiative Transfer Model (CRTM; Weng et al. 2005 ; Han et al. 2006

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B. L. Cheong, R. D. Palmer, and M. Xue

, Krajewski et al. (1993) used a simulation scheme to generate radar-estimated rainfall fields without simulating time series data. Radar measurements, that is, reflectivity and differential reflectivity, were directly derived from a two-dimensional stochastic space–time model of rainfall events and drop size distribution. These radar-derived measurements were then used to estimate rainfall rate. Anagnostou and Krajewski (1997) presented a similar simulation procedure, with the addition of vertical

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Jian Zhang, Carrie Langston, and Kenneth Howard

a background atmospheric temperature profile. The VPRs are derived from volumetric data from WSR-88Ds and are segregated for convective and stratiform precipitation, and the brightband layer information is derived from stratiform VPRs only. The new BBID scheme has been evaluated using about 7 months of WSR-88D data in the CONUS domain. The results indicate that the BBID algorithm can provide physically realistic BB layer information that is consistent with the conceptual model and matches the

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Vincent T. Wood and Luther W. White

:// .] Bluestein, H. B. , Weiss C. C. , and Pazmany A. L. , 2004 : Doppler radar observations of dust devils in Texas . Mon. Wea. Rev. , 132 , 209 – 224 . Burgers, J. M. , 1948 : A mathematical model illustrating the theory of turbulence . Adv. Appl. Mech. , 1 , 197 – 199 . Cantor, B. A. , Kanak K. M. , and Edgett K. S. , 2006 : Mars Orbiter Camera observations of Martian dust devils and their tracks (September 1997 to January 2006) and evaluation of theoretical vortex

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Lichuan Wu, David Sproson, Erik Sahlée, and Anna Rutgersson

stress are applied to an effective roughness length in numerical models, which improved model performances ( Makin 2005 ; Kudryavtsev and Makin 2011 ; Liu et al. 2011 ; Wu et al. 2015b , 2016 ). To consider the two-way interaction between waves and the atmosphere, a coupled wave–atmospheric model was developed at the European Centre for Medium-Range Weather Forecasts (ECMWF) in the middle of the 1990s ( Janssen 2004 ). In the coupled model, the Integrated Forecasting System (IFS) is coupled with

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James S. Bennett, Frederick R. Stahr, Charles C. Eriksen, Martin C. Renken, Wendy E. Snyder, and Lora J. Van Uffelen

and vehicle attack angle, either assumed or inferred from a flight model, to estimate speed along the glide slope (see discussion of attack angle under section 2 ). In lieu of these instruments, most vehicle velocities are estimated using a flight model ( Eriksen et al. 2001 ). Prior work assessing the overall accuracy of these estimated glider velocities suggests that flight models can estimate velocities through the water to within 1 cm s −1 both vertically ( Merckelbach et al. 2010 ; Frajka

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