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R. Cifelli, V. Chandrasekar, S. Lim, P. C. Kennedy, Y. Wang, and S. A. Rutledge

been combined into algorithms that select the most appropriate rainfall relation for a given set of dual-polarization characteristics. Investigators have given different names for this combination approach (e.g., “synthetic,” “optimal,” or “blended”). In this paper, we refer to any algorithm that utilizes one or more rainfall estimators and selects an individual rainfall estimator depending on the radar-observed characteristics ( Z h , Z dr , K dp ) as an optimization rainfall algorithm. Several

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John M. Krause

; Kumjian 2013a , b , c ). The algorithm described in this paper—MetSignal—is scheduled for incorporation into the WSR-88D system on the Open Radar Product Generator (ORPG) as part of build 17, which is scheduled for deployment in late 2016. The output from the MetSignal algorithm will be used in the ORPG to identify meteorological signal locations for the computation of K DP and QPE. The development and deployment of dual-polarization radar allows meteorologists to better discriminate between

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Liang Liao and Robert Meneghini

time ( Grecu et al. 2011 ; Seto and Iguchi 2015 ; Liao and Meneghini 2019 ). Adjustment factors at each gate/profile are determined by optimizing predefined cost functions that constrain radar measurements. Early versions of the DPR algorithms, such as version-3 algorithms, rested on the DFR-based technique, which is, in principle, capable of fully characterizing spatial and temporal DSD variations. However, because of the fact that dual solutions exist in estimating mass-weighted diameter ( D m

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Keith D. Hutchison, Barbara D. Iisager, Thomas J. Kopp, and John M. Jackson

VIIRS will collect data in 22 bands ( Hutchison and Cracknell 2005 ). A key product created with both MODIS and VIIRS sensors is the cloud mask, which is generated in both algorithms using sophisticated logic that includes a series of cloud detection tests. Although the MODIS cloud mask (MCM) algorithm has evolved since the launch of MODIS on the Terra spacecraft in December 1999 ( Ackerman et al. 1997 , 2002 ), the VIIRS cloud mask (VCM) algorithm was based upon the earliest MCM version ( Reed

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Donglian Sun, Yunyue Yu, Li Fang, and Yuling Liu

long been an interesting and challenging research area in thermal remote sensing ( Lorenz 1986 ; Nerry et al. 1990 ). During the past decades, significant satellite-based LST efforts have been focused on polar-orbiting satellites by using several types of split-window (11 and 12 μ m) regression algorithms, which are largely statistical–empirical solutions used to determine the relationship between surface skin and at-sensor brightness temperatures ( Price 1984 ; Ulivieri and Cannizzaro 1985

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Changyong Cao, Kenneth Jarva, and Pubu Ciren

and coverage, and land surface temperature. The HIRS calibration algorithm directly affects the radiance accuracy and thus indirectly affects the product quality at all levels. This is especially true for climate change detection studies using the HIRS data, where a calibration algorithm change may have significant impacts on their analyses and results. HIRS is one of the primary instruments for operational atmospheric sounding carried on National Oceanic and Atmospheric Administration (NOAA

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Ali H. Omar, David M. Winker, Mark A. Vaughan, Yongxiang Hu, Charles R. Trepte, Richard A. Ferrare, Kam-Pui Lee, Chris A. Hostetler, Chieko Kittaka, Raymond R. Rogers, Ralph E. Kuehn, and Zhaoyan Liu

top-of-atmosphere radiation to relate satellite-based observations to aerosol properties by using theoretical models. These models are usually based on measurements or established climatologies (e.g., d’Almeida et al. 1991 ; WCRP 1986 ) In most cases these algorithms make assumptions about the vertical distribution of aerosols and surface reflectance, all of which have significant contributions to the top-of-atmosphere radiation. OMI ( Levelt et al. 2006 ) uses two spectral regions—17

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Timothy A. Alberts, Phillip B. Chilson, B. L. Cheong, and R. D. Palmer

matched filters are specifically designed to maximize the signal-to-noise ratio of the backscattered signal, mismatched filters aim to suppress the effects of range–time sidelobes. Additionally, data obtained from an experimental weather radar were artificially phase coded to simulate pulse compression in order to validate the weather radar simulator results as well as to examine any additional effects that may be encountered in an operational environment. Traditional tornado detection algorithms use

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Yongxiang Hu, David Winker, Mark Vaughan, Bing Lin, Ali Omar, Charles Trepte, David Flittner, Ping Yang, Shaima L. Nasiri, Bryan Baum, Robert Holz, Wenbo Sun, Zhaoyan Liu, Zhien Wang, Stuart Young, Knut Stamnes, Jianping Huang, and Ralph Kuehn

prelaunch CALIPSO cloud phase algorithm, which is used in the release 2 data product, is based primarily on theoretical model simulations of lidar backscatter and polarization ( Hu et al. 2001 ). In the prelaunch CALIPSO phase algorithm, the depolarization threshold values that separate water and ice clouds are a function of layer-integrated attenuated backscatter coefficients. With this approach, we have found that horizontally oriented ice (HOI) cloud particles may be classified as either ice or water

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Francesco Silvestro, Nicola Rebora, and Luca Ferraris

task is to analyze if a relatively simple algorithm, which involves polarimetric variables for estimating rain rate, can perform well in a real-time framework. The main objective of this work was to investigate the possible improvements to operational polarimetric rainfall estimation and to make a comparison with the use of traditional Z–R techniques. In addition, this work has enabled polarimetric capabilities to be tested on a C-band operational system. From September 2005 to October 2007, nine

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