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W.-K. Tao, T. Iguchi, and S. Lang

-resolving models (CRMs) are regularly used to build lookup tables (LUTs) for LH retrieval algorithms (see the review papers by Tao et al. 2006 , 2016a ). Currently, two different LH algorithms, the Goddard convective–stratiform heating (CSH) and the Japanese spectral latent heating (SLH), are being used to produce standard LH products for both the TRMM and GPM periods. Table 1 shows the key references, inputs, CRM-simulated cases, and the LUTs used in the CSH and SLH algorithms. The CSH- and SLH

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Ali R. Mohebalhojeh and David G. Dritschel

1. Introduction The simultaneous use of “grid” and “contour” representations for the materially conserved field of potential vorticity (PV), or some approximation to PV-like quasigeostrophic PV, is the main novel feature in the contour advective semi-Lagrangian (CASL) algorithms developed since the original work by Dritschel and Ambaum (1997) . The PV field is assumed to have a discrete distribution (i.e., a number of level sets divided by contours or PV jumps). Mathematically, the discrete

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Yoo-Jeong Noh, John M. Forsythe, Steven D. Miller, Curtis J. Seaman, Yue Li, Andrew K. Heidinger, Daniel T. Lindsey, Matthew A. Rogers, and Philip T. Partain

the first next-generation polar-orbiting satellite of the Joint Polar Satellite System (JPSS; Goldberg et al. 2013 ) series. VIIRS provides valuable atmospheric, cloud, and surface information for both weather and climate applications. The original JPSS CBH environmental data record (EDR), based on the algorithm of Hutchison (2002) and Hutchison et al. (2006) , was adapted to VIIRS as a first attempt to retrieve three-dimensional cloud fields on a large scale from an operational satellite

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Pierre S. Farrugia, James L. Borg, and Alfred Micallef

linearization process as a measure of angular dispersion, but they differ by a multiplicative factor. It was only recently that these two quantities were related, after Farrugia and Micallef (2004) proposed a new geometric measure to describe circular variables. The development of an algorithm that can be used to determine the standard deviation of wind direction has encountered the same difficulties, as has already been pointed out by Fisher (1987) . In fact, a number of equations have been proposed as

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Y. Morille, M. Haeffelin, P. Drobinski, and J. Pelon

large-scale analysis of available datasets. Furthermore, in the context of new satellite missions carrying active remote sensing payloads, such as the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO; Winker et al. 2003 ), ground-based lidar observatories have an increasingly important role to play in establishing regional climatologies that will tie in the temporally sparse global-scale satellite measurements. The need for robust algorithms designed to process large

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Quanhua Liu and Fuzhong Weng

cross-track measurements due to the change of the scanning angle is called limb effect and can be as much as 30 K for the 23.8-GHz water vapor channel and 15 K for troposphere sounding channels ( Goldberg et al. 2001 ). Because the limb effect is often stronger than the real variation of the signatures from scenes, the unadjusted measurements prevent the objective analysis of weather systems and may make the regression retrieval algorithm complicated. More important, averaging satellite brightness

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David R. Jackett, Trevor J. McDougall, Rainer Feistel, Daniel G. Wright, and Stephen M. Griffies

these terms was lacking. The 25-term equation was also motivated by publication of the Feistel and Hagen (1995 , hereafter FH95 ) equation of state, which was based on a Gibbs thermodynamic potential. This equation turned out to be more accurate than, and addressed several weaknesses in, the well-established International Equation of State of Seawater ( Fofonoff and Millard 1983 ). MJWF03 also presented a new algorithm for the computation of potential temperature that was thermodynamically

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Lindsey M. Richardson, Jeffrey G. Cunningham, W. David Zittel, Robert R. Lee, Richard L. Ice, Valery M. Melnikov, Nicole P. Hoban, and Joshua G. Gebauer

; Zittel et al. 2014 ). This paper describes the development and testing of an automated algorithm for detecting CABS on operational WSR-88Ds. Bragg scatter is caused by turbulent inhomogeneities with sizes around one-half of a transmitted radar wavelength (e.g., Cowley 1995 ; Hardy and Katz 1969 ; Knight and Miller 1993 ; Doviak and Zrnić 2006 , chapter 11). Bragg scatter has been observed as a layer in clear air and developing clouds, and it is mostly associated with refractivity gradients

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Jeffrey C. Snyder, Alexander V. Ryzhkov, Matthew R. Kumjian, Alexander P. Khain, and Joseph Picca

, whereas the Z DR column extends to ~6.3 km AGL. Since the BWER can be characterized as a minimum within a local maximum (i.e., the convective storm) in reflectivity factor, it is not particularly easy to design an algorithm to diagnose this feature, although Lakshmanan and Witt (1997) describe such an algorithm. In addition, merging convective storms or other processes can create local minima in Z H that are not associated with BWERs (at least how the term BWER is typically used). In contrast

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Adam L. Houston, Noah A. Lock, Jamie Lahowetz, Brian L. Barjenbruch, George Limpert, and Cody Oppermann

of using radar data. Moreover, each of these studies relies on an objective algorithm for thunderstorm identification that, in contrast to manual identification strategies, is repeatable and tunable. However, none of these methods operates on multiple radars covering a large region and includes lightning. Mohee and Miller (2010) and Davini et al. (2012) utilize multiple radars over a regional footprint (North Dakota and northwestern Italy, respectively) but neither integrates lightning into

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