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Qingtao Song, Tetsu Hara, Peter Cornillon, and Carl A. Friehe

surface wind stress at the meso- γ scale (2–20 km) in the vicinity of an SST front and to evaluate the performance of the model using the selected parameterization. This selection and evaluation was done through comparison of MM5 simulations with in situ observations made during the Frontal Air–Sea Interaction Experiment (FASINEX) ( Friehe et al. 1991 ). Admittedly, the response of the MM5 boundary layer has been extensively tested over land ( Pleim and Xiu 1995 ; Davis et al. 1999 ; Bright and

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Alain Protat and Isztar Zawadzki

). The next subsection evaluates the performance of this basic constraining model (5) . b. Performance of the basic constraining model The basic retrieval procedure (described in section 2a ) and computer code were verified using a simulated data set described in Protat et al. (1998) . A relative error of less than 1% was found for the dynamic perturbations. These errors are attributed to the discretization of the momentum and continuity equations involved in the retrieval procedure. In a

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David A. Siegel and Albert J. Plueddemann

, Massachusetts4 April 1990 and 23 October 1990ABSTRACT Several popular techniques employed to remotely sense oceanic velocity fields utilize the Doppler shifts ofbackscattered radiation (such as sound or light) from suspended panicles to estimate fluid velocities. Implicitin this use is the assumption that the motion of the panicles and the fluid parcels about them is identical. Here,a simple dynamical model of a solid sphere in a unidirectional oscillating flow is used to evaluate the effects

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Paola Malanotte-Rizzoli and Roberta E. Young

recent assimilation applications in various regional systems of the World Ocean. One such effort focused on the short-term prediction of the Gulf Stream system in the DAMEE GSR (Data Assimilation and Model Evaluation Experiments Gulf Stream Region) for which the strong motivation was provided by the U.S. Navy’s persistent need for improved capability in ocean nowcast–forecast systems ( Willems et al. 1994 ). The objective of DAMEE GSR was to assess quantitatively the nowcast–forecast capability of

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Jacques Testud, Paul Amayenc, Xiankang Dou, and Taoufix Tani

-derived estimate of rain rateis less sensitive to the DSD than the SF methods. Emphasis was put on the evaluation of effects ofNUBF in the algorithm performances because of itsimpact on the antenna beam resolution requirement fora spaceborne rain radar. But, the algorithms sensitivityto the speckle noise, the radar calibration error, and theDSD variability, were also investigated. The simulationtool was applied to model raincells with a wide rangeof Rmax and D/L ratios. It was also applied, for

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Hangzhou Wang, Liwen Nan, Jiwan Han, Ying Chen, and Haocai Huang

correction model was developed to correct temperature-induced biases in the system output, which was then combined with the approach of correcting the spectral sensitivity of the system to determine the absolute incident irradiance entering the profiling system. Finally, a field examination of the system was carried out in the Arctic sea ice environment to validate the overall performance and practicability of the system. 2. Methods a. Measurement principle To obtain long-term measurements of solar

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E. E. Clothiaux, M. A. Miller, B. A. Albrecht, T. P. Ackerman, J. Verlinde, D. M. Babb, R. M. Peters, and W. J. Syrett

)ABSTRACT The performance of a 94-GHz radar is evaluated for a variety of cloud conditions. Descriptions of the radarhardware, signal processing, and calibration provide an overview of the radar's capabilities. An important component of the signal processing is the application of two cloud-mask schemes to the data to provide objectiveestimates of cloud boundaries and to detect significant returns that would otherwise be discarded if a simplethreshold method for detectability was applied to the return

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Stanford B. Hooker and James Aiken

of normal deck operations. These changes in temperature were particularly noticeable in the final leg of the voyage between Montevideo and Stanley when the outside air temperature was the coldest. To check the stability of the radiometers used during AMT-3, and to monitor the performance of the SQM, a calibration evaluation and radiometric testing (CERT) session was defined. A sequence of procedures was implemented for each CERT session (with minor variations to test SQM performance aspects or to

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D. Goldin and C. Lukashin

presence of the aerosols. 7. Polarization distribution models for the angle of linear polarization a. χ PDMs for the cloudless-sky over ocean scene We now turn to the angle of linear polarization χ . As mentioned in the beginning of section 6 , for the precise evaluation of the uncertainty in reflectance due to polarization, its dependence on χ for each viewing geometry configuration needs to be included. Thus, the χ PDMs, analogous to P PDMs, need to be constructed. Using the definitions in

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V. K. Anandan, M. Shravan Kumar, and I. Srinivasa Rao

measurements are of known quality. Sodar data are frequently compared with the measurements of in situ sensors mounted on towers, radiosondes, and tethered balloons, and also can be compared with ground-based sensors such as lidars and other sodars. Testing using the same type of device is the primary means of assessing the performance of the sodar. Since different instruments use different techniques for measuring winds and other parameters, each system has its own biases and measurement limitations

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