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Zhengzheng Li, Yan Zhang, and Scott E. Giangrande

Gaussian mixture model (GMM) ensures convergence to the prior distribution of dual-polarization variables, the GMPE (a minimum variance unbiased estimator) was shown to outperform PLRs in both rainfall-rate estimation and attenuation correction using simulated polarimetric radar measurements. However, the performance of the GMPE has not been tested for real-world rainfall applications. Rainfall-rate estimators can be developed either through measurements or simulations. Rainfall-rate estimators

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Hyun Mee Kim and Dae-Hui Kim

1. Introduction The initial conditions obtained by assimilating the model background and observations are used to predict weather in numerical weather prediction (NWP). Because individual observations assimilated to produce the initial conditions for the prediction contribute differently to the performance of forecasts, the impact of individual observations on the forecasts needs to be evaluated quantitatively to improve the performance of the NWP. The impact of real observations on forecasts

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Peyman Rahnama, Yves J. Rochon, Ian C. McDade, Gordon G. Shepherd, William A. Gault, and Alan Scott

determined for each pixel without inversion that represents some weighted average wind along the line of sight of each pixel. The random noise standard deviations of these winds are derived through propagation of the measurement noise variances. Wind differences can serve in evaluating the sensitivity to different instrument characteristics. These standard deviations and differences are useful in conducting evaluations on instrument performance and conditions. The calculated wind random error standard

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Michel Chong and Stéphanie Cosma

in MUSCAT properly takes into account the orography-induced air circulation. More significant is the resemblance between the horizontal components deduced from MUSCAT ( Figs. 4c, 4e , 5c, 5e ) and the model ( Figs. 4d, 4f , 5d, 5f ), which were marked by strong shear zones. These figures clearly show the performances of MUSCAT in providing highly reliable horizontal wind components. An overall comparison can be summarized in Fig. 6 , which shows the statistical distributions of the wind

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Yanting Wang and V. Chandrasekar

et al. 2005 ). The fine-tuning of this relation is not the focus of this paper. Instead, the performance of rainfall estimation from the DCAS network observations is of essential interest here. As a baseline of comparison, one of KOUN’s R ( K dp ) relations presented by Ryzhkov et al. (2005) is chosen and adapted to X band, which is repeated here as This relation is based on the measured DSD from the same coverage area and a drop shape model as specified by Brandes et al. (2002) . It has

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Senliang Bao, Ren Zhang, Huizan Wang, Hengqian Yan, Yang Yu, and Jian Chen

salinity profile reconstruction model. The profile data from 2014 are then used for testing the model. 4. The performance of the FOAGRNN in estimating salinity profiles a. Comparison with the linear method To evaluate the performance of the FOAGRNN method, the multiple linear regression and FOAGRNN methods are used to retrieve salinity profiles for the tropical Pacific Ocean and the Kuroshio Extension region during 2014. Then, the RMSE of estimated profiles from the two methods against in situ

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Rod Frehlich and Robert Sharman

. Summary and discussion We provide here a technique to evaluate lidar performance statistics (bias, average, and standard deviation) based on coupled numerical simulations of pulsed Doppler lidar and a prescription of a wake vortex pair to provide “truth.” In particular, the performance of the ML estimation algorithms of wake vortex parameters was evaluated to establish the optimal performance achievable by a pulsed Doppler lidar scanning perpendicular to the flight path. Using the known

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R. Pinkel and J. A. Smith

velocity estimates from incoherentDoppler sounders. The method involves transmitting a number of repeats of a broadband "subcode." TheDoppler shift is estimated from the complex autocovariance of the return, evaluated at a time lag equal to thesubcode duration. The repeat-sequence code is an extension of the simple pulse-train concept developed in theearly days of radar. By transmitting codes, rather than discrete pulses, the average transmitted power is increased.A model is developed here to predict

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Simone Tanelli, Eastwood Im, Satoru Kobayashi, Roberto Mascelloni, and Luca Facheris

frequency components of the pointing error below 1 Hz, and that overall accuracy of 1 m s −1 or better can be achieved even when extremely strong convective cells are present. The results obtained through CFT were compared to those obtainable through standard spectral moments estimators once a simplified model to correct for NUBF-induced biases is implemented. This second approach guarantees acceptable results in moderate NUBF conditions, but its performances are more sensitive to the accurate

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Malgorzata Szczodrak, Peter J. Minnett, Nicholas R. Nalli, and Wayne F. Feltz

M-AERI. The performance of the NCEP and ECMWF model-based retrievals of the atmospheric profiles is evaluated by comparison with profiles obtained by coincident radiosonde measurements and with M-AERI retrievals obtained using the radiosonde profiles as a first guess. This study is based on data collected during the 2004 Aerosol and Ocean Science Expedition (AEROSE; Nalli et al. 2006 ). 2. Instruments and data AEROSE was a multidisciplinary oceanographic field campaign conducted in the tropical

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