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William A. Gallus Jr. and Moti Segal

adjustment might suggest that with both of the convective schemes, the precipitation is particularly sensitive to the amount of water vapor present, since the onion adjustment results in a removal of water vapor at lower levels. Despite the absolute changes in ETSs being small for the cold pool initialization, the paired t test indicated significance of the changes at the 95% confidence level for several thresholds. The statistical significance is assisted by small variance in the ETS differences

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I-Han Chen, Jing-Shan Hong, Ya-Ting Tsai, and Chin-Tzu Fong

single observation tests by laying pseudo observations at the model’s lowest sigma level. The maximum analysis increment and its e -folding length are summarized in Table 2 . With the current BEC, the assimilating of momentum variables spread to higher levels than temperature and water vapor. Table 1. Prescribed observation errors and gross check thresholds used in this study. Table 2. Summary of single observation experiments. For radar data assimilation, cloud control variables are required. In

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Thomas M. Hamill, Robert P. D'Entremont, and James T. Buntin

observations. The merge processor combines the satellite- andconventional-derived cloud analyses into a final nephanalysis. Finally, the bogus processor allows forecasters tomanually correct the nephanalysis where appropriate. The RTNEPH has been extensively redesigned, primarily to improve analyses of total and layered cloudamounts generated from IR data. Recent enhancements include the use of regression equations to calculateatmospheric water vapor attenuation, an improved definition of surface

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Keyi Chen, Stephen English, Niels Bormann, and Jiang Zhu

channels (3–5) are sensitive to the water vapor around 400, 600, and 800 hPa, respectively. The nominal spatial resolution is 15 km at nadir, and the swath width is 2700 km with a total of 98 fields of view (FOVs) along each scan line. The MWHS instrument is flown on the FY-3A with an equatorial crossing time (ECT) of 1015 LT (all ECTs are local time; all other times in this article are UTC) (descending) and on the FY-3B with an ECT of 1340 (ascending). Table 1. MHS and MWHS channel

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Michael Lieder and Günther Heinemann

-based studies (which are also very rare for the Antarctic) lack a validation by observational data in general. The goal of the present study is to use multisensor satellite data of the FROST dataset in conjunction with mesoscale model simulations for the investigation of Antarctic MCs. Satellite imagery and retrievals are used for synoptic and subsynoptic description of the MCs, but also serve to validate the model simulations by comparing near-surface wind and integrated water vapor from the model fields

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Kai-Yu Ma and Lance F. Bosart

convective complex appeared tobe comparable to what has been seen in similar cases over North America. Warm air advection in the lower troposphere appeared to help trigger the rainfall through weak synopticscale ascent of I-2 cm s-~. An analysis of the water vapor flux revealed the South China Sea as a moisturesource in the surface-to-850 mb layer, and the Indian subcontinent-Bay of Bengal region as the moisture sourcein the 850-500 mb layer.1. Introduction This paper presents a synoptic analysis

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Tadashi Fujita, David J. Stensrud, and David C. Dowell

procedure, the precipitation forecasts and resampled observations are compared at every grid element for each ensemble member, and an adjustment of the model fields in the corresponding vertical column (and in some cases also in the columns around it) is performed if they do not coincide. The adjustment is performed on the model vertical profiles of temperature ( T ), water vapor mixing ratio ( q ), and vertical velocity ( w ), and is the same for two cases studied as described in detail below. Some

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Zheng Lu, Yan Guo, Jiangshan Zhu, and Ning Kang

anomalous southwesterly from the northern South China Sea (SCS), water vapor is transferred to South China. The anomalous northeasterly from the Yangtze River area hinders the farther northward transfer of water vapor, resulting in anomalous wet conditions at the southern coast. Moreover, the anomalous southwesterly and northeasterly meet in South China, leading to local convergence and ascent. The above situation gives rise to consistently sufficient rainfall at the 14 stations, especially at the

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Weiwei Li, Zhuo Wang, Melinda S. Peng, and James A. Ridout

, and motion vectors derived from geostationary satellite IR data were used to advect the precipitation features. CMORPH thus better represents the spatial structure of precipitation compared to Tropical Rainfall Measuring Mission (TRMM) 3B42. To be consistent with the analysis and forecast data, daily means were derived from the CMORPH precipitation and regridded to the 1.0° × 1.0° resolution. Column water vapor (CWV) and precipitation from the version 7 Special Sensor Microwave Imager Sounder (SSM

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Banghua Yan and Fuzhong Weng

1. Introduction The Special Sensor Microwave Imager/Sounder (SSMIS), which measures the thermally emitted radiation from the earth at 24 channels from 19 to 183 GHz (see Table 1 ), is the first conically scanning microwave sensor to provide temperature and water vapor sounding information. Today, there are three SSMIS instruments flown aboard the Defense Meteorological Satellite Program (DMSP) F-16 , F-17 , and F-18 platforms. In the next decade, there will be two more SSMIS instruments

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