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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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Lohitzune Solabarrieta, Sergey Frolov, Mike Cook, Jeff Paduan, Anna Rubio, Manuel González, Julien Mader, and Guillaume Charria

datasets. In this way, the number of comparison tracks increased substantially (see Fig. 3 , top and middle, as an example of the comparison track obtained for one particle). For the analysis of the forecast model performances in a longer period, trajectories have been generated every hour using trajectories launched in a regular 9 × 7 grid, covering the study area with regular node distances of 0.15° × 0.09° ( Fig. 3 , bottom). In all cases, the trajectories of the particles going out of the HF radar

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Zijun Gan, Youfang Yan, and Yiquan Qi

nontrivial test bed for the ocean models and allow for evaluation of their performance in the SCS. The paper is organized as follows. In section 2 , the data are introduced briefly. In section 3 , a short review of scaling analysis methods is presented to make the paper more self-contained. In section 4 , we present the results and discussions, and the conclusions are drawn in section 5 . 2. Study area and data used The study area is located between 0.5°–24.5°N latitude and 99.5°–124.5°E longitude

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T.L. Anderson, D.S. Covert, S.F. Marshall, M.L. Laucks, R.J. Charlson, A.P. Waggoner, J.A. Ogren, R. Caldow, R.L. Holm, F.R. Quant, G.J. Sem, A. Wiedensohler, N.A. Ahlquist, and T.S. Bates

used to measure the scattering coefficient of laboratory-generated particles of known size andrefractive index. Specifically, it evaluates the performance of a high-sensitivity, three-wavelength, total scatter/backscatterintegrating nephelometer (TSI, Inc., model 3563). Sources of uncertainty associated with the gas-calibrationprocedure, with photon-counting statistics, and with nonidealities in wavelength and angular sensitivity areinvestigated. Tests with particle-free gases indicate that

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Ali Tokay, David B. Wolff, and Walter A. Petersen

Parsivel could estimate the size of drizzle drops down to a 0.1-mm diameter with modifications made to the optical system. Third, they stated that the Parsivel estimates the size and fall velocity of snowflakes and is useful for discriminating the hydrometeor type, which makes the Parsivel a present weather sensor. LJ00 evaluated the performance of the Parsivel through comparison with a collocated impact-type Joss–Waldvogel (JW) disdrometer ( Joss and Waldvogel 1967 ) and a recording Hellmann

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Anant Parekh, Rashmi Sharma, and Abhijit Sarkar

). This leads us to believe that the different measurements can play both complimentary and supplementary roles. Their integration can be achieved after evaluating their interconsistencies and comparisons individually and with the analysis of known numerical models. Intercomparison and validation of satellite retrievals with in situ observations is also rendered complicated by several important differences between satellite and in situ measurements, for example, spatiotemporal inhomogeneity between in

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