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Aurélie Bouchard, Florence Rabier, Vincent Guidard, and Fatima Karbou

, improvements in the representation of surface emissivity and temperature are necessary to decrease the number of observations rejected during the assimilation system. In the following, studies toward a better estimation of surface emissivity at microwave frequencies will be presented as well as feasibility studies undertaken to assimilate as many relevant infrared and microwave observations as possible over Antarctica. b. Microwave observations Satellite instruments measure the top

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Gerald M. Heymsfield and Richard Fulton

) ABSTRACT Observations of an isolated group of Oklahoma thunderstorms from NASA's high altitude ER-2 aircraft arepresented. These observations include passive radiometric measurements at frequencies in the microwave (92,183 GHz), infrared (10.7 ~m) and visible portion of the spectrum from a perspective above the storm top.Direct measurements of cloud top height were also collected using a pulsed lidar instrument. These remoteobservations are discussed and compared with coincident radar data from the

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Daniel J. Cecil and Edward J. Zipser

°–1° radius latent heat release. Would other microwave channels that are more intimately tied to latent heat release, but have lower resolution than the 85 GHz 13 km × 15 km footprint, likewise produce such high correlations? The lack of a relationship between indicators of intense convection (such as lightning) and tropical cyclone deepening seems to be in conflict with previous reports. Would a more detailed dataset (such as lightning observations from a geostationary satellite) resolve this conflict

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Xin Lin, Sara Q. Zhang, and Arthur Y. Hou

on the temporal sampling and spatial coverage of observations. The Global Precipitation Measurement (GPM) mission being planned for the beginning of the next decade is based on the concept of providing frequent global precipitation measurements using a spaceborne precipitation radar as a calibrator of a constellation of passive microwave radiometers. GPM is designed to extend the successful Tropical Rainfall Measuring Mission (TRMM; Simpson et al. 1988 ) in the Tropics to higher latitudes, but

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M. A. Filiberti, L. Eymard, and B. Urban

486 MONTHLY WEATHER REVIEW VOLUME122Assimilation of Satellite Precipitable Water in a Meteorological Forecast ModelM. A. FILIBERTI AND L. EYMARD CRPE I CNET / CNRS Vdlizy, France B. URBANMdMo-France, Toulouse, France(Manuscript received 15 February 1993, in final form 30 July 1993) The lack of local humidity observations over a large portion of the globe hinders any

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Christopher S. Velden, Brian M. Goodman, and Robert T. Merrill

15 March 1990, in final form 13 July 1990) ABSTRACT A method is examined for estimating the intensity of western North Pacific tropical cyclones from satellitepassive microwave observations. Vertical profiles of atmospheric temperature derived from radiances remotelysensed by the Microwave Sounding Unit (MSU) onboard the current NOAA series of polar orbiting satellitesare used to depict upper-tropospheric warm anomalies associated with these storms. Data from a large

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Xu Lu and Xuguang Wang

experiment, observations such as Stepped Frequency Microwave Radiometer (SFMR), flight-level (FL), and tail Doppler radar (TDR) observations were collected through the NOAA WP-3D aircraft ( Rogers et al. 2006 , 2013 ). The different observations primarily focus on the inner-core structures of hurricanes at various levels. For example, the SFMR samples only the surface, the FL observations are usually centered around 700–800 hPa, and the TDR scans three-dimensional (3D) structures with the number of

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Xiaolei Zou, Zhengkun Qin, and Fuzhong Weng

the Advanced Research core of the Weather Research and Forecasting (WRF) model (ARW). Imager radiances from GOES-11/12 , temperature sounding data from the Advance Microwave Sounding Unit-A (AMSU-A), moisture sounding data from the Microwave Humidity Sounder (MHS), as well as infrared radiances from the Atmospheric Infrared Sounder (AIRS) and High Resolution Infrared Sounder (HIRS), were individually added to the conventional data in GSI and all show some positive impacts. However, it was found

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Philippe Lopez and Peter Bauer

1. Introduction During the last decade, the data assimilation community has attempted to find the optimal way to extract information from observations that are affected by clouds and/or precipitation, with the hope that this could help improve operational weather analyses and forecasts. A large amount of such observations is already available from various spaceborne platforms such as the Special Sensor Microwave Imager (SSM/I), Special Sensor Microwave Imager Sounder (SSM/IS), Tropical Rainfall

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Sara Q. Zhang, Milija Zupanski, Arthur Y. Hou, Xin Lin, and Samson H. Cheung

1. Introduction Precipitation is a crucial component in the hydrological cycle of the earth and has a profound influence on the weather and climate at global and regional scales. In recent decades observations of precipitation with global coverage have become available from spaceborne instruments. Spaceborne microwave sensors have the capability to observe precipitation via interaction of hydrometeors in the atmosphere with the radiation field. Following the success of the Tropical Rainfall

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