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Robert Rogers

with convective and stratiform precipitation in MCSs are also seen using the partitioning algorithm discussed here. The primary feature used in the convective–stratiform partitioning algorithm is the horizontal distribution of reflectivity, based on the algorithm in Steiner et al. (1995) . The reflectivity criteria used to identify convective points relies on three factors: intensity of reflectivity, peakedness (excess of reflectivity over a background value), and all points within a prespecified

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Robert Cifelli, Timothy Lang, Steven A. Rutledge, Nick Guy, Edward J. Zipser, Jon Zawislak, and Robert Holzworth

within 1 dB of the PR and no correction was applied. Attenuation corrections were also applied to the C-band reflectivity data to account for signal loss in heavy rainfall. The attenuation algorithm of Patterson et al. (1979) was used. No attenuation correction was applied to the NPOL (S-band) system. The radar data were then interpolated to a Cartesian grid using the National Center for Atmospheric Research REORDER software ( Mohr et al. 1986 ) extending 120 km in x and y from a fixed point

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R. A. Hansell, S. C. Tsay, Q. Ji, N. C. Hsu, M. J. Jeong, S. H. Wang, J. S. Reid, K. N. Liou, and S. C. Ou

Liou 1992 ). The code also employs a parameterized version of the LW water vapor continuum model (CKD2.4) to account for strong water vapor absorption. Modifications to the code enable time series of retrieved AERI IR AOT (scaled to λ = 0.55 μ m) and combined AERIPLUS [a physical retrieval algorithm developed by the University of Wisconsin Space Science and Engineering Center (UW-SSEC), see Feltz et al. 2003 ), used to retrieve temperature/moisture profiles from AERI radiances] and radiosonde

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Syed Ismail, Richard A. Ferrare, Edward V. Browell, Gao Chen, Bruce Anderson, Susan A. Kooi, Anthony Notari, Carolyn F. Butler, Sharon Burton, Marta Fenn, Jason P. Dunion, Gerry Heymsfield, T. N. Krishnamurti, and Mrinal K. Biswas

= 30 for dust aerosol that is used in the CALIOP aerosol extinction retrieval algorithms ( Liu et al. 2005 ; Omar et al. 2006 ). The value of S a = 36 reported here for the LASE measurements is within the wide range (30 to 80 sr) of measured S a values corresponding to dust (for a review see, e.g., Liu et al. 2008 ). As an example, Vaughan (2004) used data from the spaceborne Lidar in Space Technology Experiment (LITE) to derive values of S a = 26 ± 4.8 sr (532 nm) and S a = 35 ± 18

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Jonathan Zawislak and Edward J. Zipser

, 3-hourly 0.25° × 0.25° gridded rain rates are available from the level-3 TRMM algorithm, 3B42. The algorithm adjusts rain rates derived from geosynchronous IR observations with TRMM estimated surface rain and hydrometeor structure. c. NCEP GDAS description The Global Data Assimilation System, run by NCEP and obtained from the University Corporation for Atmospheric Research (UCAR) Data Support Center, analysis is utilized to track 700- and 925-hPa vorticity maxima and the 700-hPa wave trough. The

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Chuntao Liu, Earle R. Williams, Edward J. Zipser, and Gary Burns

compared to global lightning activity. Adv. Space Res. , 36 , 2223 – 2228 . Iguchi , T. , T. Kozu , R. Meneghini , J. Awaka , and K. Okamoto , 2000 : Rain-profiling algorithm for the TRMM precipitation radar. J. Appl. Meteor. , 39 , 2038 – 2052 . Israel , H. , 1973 : Fields, Charges, Currents . Vol. II, Atmospheric Electricity, Israel Program for Scientific Translation, 796 pp . Jorgensen , D. P. , M. A. LeMone , and S. B. Trier , 1997 : Structure and evolution of

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Zhuo Wang, M. T. Montgomery, and T. J. Dunkerton

the preceding caveats, we believe the algorithm used is adequate for the purpose of understanding storm development and organization in the pregenesis stage, which (as will be shown here) are insensitive to variations of grid spacing less than 9 km. Figures 2a and 2b show a snapshot of the distribution of the precipitation rate and precipitation types superimposed on the translated streamlines at 40 h. Both precipitation rate and precipitation types are derived from the output of the innermost

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Stephen R. Guimond, Gerald M. Heymsfield, and F. Joseph Turk

limitations, but the magnitudes are much larger than those using the Demuth et al. (2004) algorithm. The root-mean-square errors for the raw retrievals (removed from heavy precipitation) are less than 2°C ( Goldberg 1999 ; Kidder et al. 2000 ). b. EDOP The EDOP is an X-band (9.6 GHz) Doppler radar with fixed nadir and forward (33° off nadir) beams, each with a 2.9° beamwidth. Measurements are taken from the high-altitude (20 km) ER-2 aircraft every 0.5 s with a 200 m s −1 ground speed providing some

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Scott A. Braun, Michael T. Montgomery, Kevin J. Mallen, and Paul D. Reasor

then σ c a c , σ s a s , and σ e a e . The separation into convective and stratiform components was accomplished using a method similar to that of Tao et al. (1993) . First, all grid points with surface rainfall rates greater than 20 mm h −1 were classified as convective. Next, a texture algorithm was used, whereby grid points having rainfall rates twice as large as the average of their nearest 24 neighbors were classified as convection. If a grid point is designated as convective in this way

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Oreste Reale, William K. Lau, Kyu-Myong Kim, and Eugenia Brin

investigated using a high-resolution global DAS based upon the gridpoint statistical interpolation (GSI) analysis algorithm developed by the National Centers for Environmental Prediction (NCEP) Environmental Modeling Center, documented in Wu et al. (2002) . The NASA GEOS-5 combines a modified version of the previously referenced DAS with the NASA atmospheric global forecast model, as documented in Bosilovich et al. (2006) and more extensively in Rienecker et al. (2008) . One important aspect of the

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