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M. Tugrul Yilmaz, Paul Houser, Roshan Shrestha, and Valentine G. Anantharaj

hinders the deployment of microwave instruments on geostationary platforms. Microwave-based estimates are generated by using emitted or scattered radiation sourced from raindrops or the earth’s surface, respectively. Emission- or scatter-based algorithms make use of emitted radiation by raindrops (land surface) over ocean (land) to estimate the precipitation amounts. Passive microwave-based products are good at detecting strong convective precipitation events but tend to miss shallow and warm rains

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Daniel Vila, Ralph Ferraro, and Hilawe Semunegus

and sense the emitted and scattered radiation by raindrops and precipitation-sized ice particles, respectively; and (iii) the conical-scan viewing geometry allows for maintaining a fixed viewing angle and a constant footprint size along the scan for each frequency ( Poe et al. 2001 ). The primary algorithm used in this particular study is an 85-GHz scattering-based algorithm over land, while a combined 85-GHz scattering and 19/37-GHz emission is used over ocean [see Ferraro (1997) appendix A1

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Song Yang, Fuzhong Weng, Banghua Yan, Ninghai Sun, and Mitch Goldberg

, land, and ice surface types), while σ ≤ 5 k is used for coastal situations. Notably, when there are not enough high quality SCO pixels between two sensors, a third satellite that has good SCO pixels with both of these two sensors is utilized as the transfer radiometer to create the desired SCO pixels (This process is normally referred as the DDT.). Therefore, the current NOAA/NESDIS SSM/I SDR intersensor calibration scheme has two major components: 1) removal of the scan-angle-dependent bias and

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B. J. Sohn, Hyo-Jin Han, and Eun-Kyoung Seo

consequence in rainfall monitoring is discussed later in this section. By contrast, underestimations of CMORPH, PERSIANN, and NRL-blended are unavoidable because the GPROF-based rain retrieval algorithm for the microwave measurement over land produces the significant underestimate, as shown in Fig. 2f , at least over the Korean Peninsula. The scatterplots and associated statistics are based on the use of rain gauge data as true rain events. Thus, the statistics obtained from scatterplots may not

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J. J. Shi, W-K. Tao, T. Matsui, R. Cifelli, A. Hou, S. Lang, A. Tokay, N-Y. Wang, C. Peters-Lidard, G. Skofronick-Jackson, S. Rutledge, and W. Petersen

of one National Aeronautics and Space Administration (NASA)-provided satellite, U.S. satellite assets from the National Oceanic and Atmospheric Administration (NOAA) and Defense Meteorological Satellite Program, and international satellites with passive microwave instruments. Two of the major objectives of the GPM mission are to measure cold-season precipitation in mid- and high latitudes over land through the use of GMI high-frequency radiometry and to further the understanding of precipitation

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Frank S. Marzano, Domenico Cimini, Tommaso Rossi, Daniele Mortari, Sabatino Di Michele, and Peter Bauer

, above 89 GHz, will be discussed and a one-dimensional (1D) variational inversion algorithm will be described. The latter will then be used to evaluate the expected retrieval errors associated with liquid and ice hydrometeor profile retrievals over ocean and land for various climatological regions. Conclusions will be drawn in section 4 . 2. Flower constellations at pseudo-geostationary scale The FLORAD small-mission concept is based on the combined used of atmospheric MMW radiometry and the Flower

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Chinnawat Surussavadee and David H. Staelin

relate retrieval discrepancies to land classification and thereby to possible terrain-related explanations. The corrections related to land classification were then implemented and used in the subsequent analyses. These differences suggest that virga, surface emissivity, storm structure, or other factors result in overestimation by AMSU over deserts, grassland, and certain other terrain. These hypotheses are then explored in a preliminary way in section 5 , in which similar effects are sought in MM5

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Cristian Mitrescu, Tristan L’Ecuyer, John Haynes, Steven Miller, and Joseph Turk

the a priori estimate of the precipitation rate while 𝗥 is the rain-rate profile to be retrieved. As mentioned above, additional information about modeled and observed PIA due to hydrometeor attenuation is introduced via the last term of the cost function using a fixed covariance 𝗦 σ that depends solely on the type of the surface (water or land). If for water bodies PIA σ can be determined with relatively good accuracy (about 2 dB after wind and temperature correction), for land surfaces it

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Long S. Chiu and Roongroj Chokngamwong

found to be outside this range. In V6 only the out-of-range pixels are rejected. Second, a land/sea mask at 0.25° resolution generated from 5′ gridded elevations/bathymetry for the world (ETOPO5; NOAA 1988 ; see online at http://www.ngdc.noaa.gov/mgg/global/etopo5.html ) is used in V4. Pixels that are within one pixel width from land are not included. In the V6 T b data, each pixel is tagged as either land or sea, and only the sea pixels are included. The third aspect involves the screening out

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Tufa Dinku, Pietro Ceccato, Keith Cressman, and Stephen J. Connor

) provides a decision support system required for monitoring desert locusts ( Ceccato et al. 2007 ). The information produced by DLIS is used by about 30 countries in the affected region to plan survey-and-control operations. This information may also be used by the international donor community to target assistance, especially during emergencies. Rainfall data are one of the inputs into the DLIS decision support system. Rainfall is very important in determining the extent and intensity of desert locust

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