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V. Mattioli, E. R. Westwater, D. Cimini, A. J. Gasiewski, M. Klein, and V. Y. Leuski

-wave observations represent another powerful method to identify spurious soundings. It is intriguing to speculate on possible uses of the 22.235-GHz T b and 183.31-GHz measurements to correct radiosonde soundings in the stratosphere. If a suitable training set of simultaneous RS90, NWS-VIZ, GSR, and MWRP observations were available, perhaps a correction could be derived and applied to both past and present soundings. At the ARM Barrow site, the MWRP has been operating since February 2004, and radiometers near

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Peter J. Marinescu, Patrick C. Kennedy, Michael M. Bell, Aryeh J. Drager, Leah D. Grant, Sean W. Freeman, and Susan C. van den Heever

, 1973 ). Radiosondes have also been used throughout the past 50 years, albeit infrequently, to estimate the vertical velocities in supercells ( Barnes 1970 ; Davies-Jones 1974 ; Davies-Jones and Henderson 1975 ; Bluestein et al. 1988 , 1989 ; Marshall et al. 1995 ; Markowski et al. 2018 ). From these radiosonde observations, the greatest reported w air values were 49 m s −1 ( Bluestein et al. 1988 ) and 53 m s −1 ( Markowski et al. 2018 ), which occurred in Texas and Oklahoma, respectively

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T. Connor Nelson, James Marquis, Adam Varble, and Katja Friedrich

. 2008 ), Cumulus Photogrammetry In situ and Doppler Observations ( Damiani et al. 2008 ), the first and second Verification of the Origins of Rotation in Tornadoes Experiments ( Rasmussen et al. 1994 ; Wurman et al. 2012 ), Mesoscale Predictability Experiment ( Weisman et al. 2015 ), and Plains Elevated Convection at Night ( Geerts et al. 2017 ) projects have sought to observe convective environments with targeted radiosonde launches deployed at finer spatiotemporal resolution than is capable by

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M. Roja Raman, M. Venkat Ratnam, M. Rajeevan, V. V. M. Jagannadha Rao, and S. Vijaya Bhaskara Rao

high-resolution GPS radiosonde observations from Gadanki revealed several important aspects of MLLJ. First, the existence of the MLLJ over Gadanki is confirmed using GPS radiosonde observations, and then the spatial and vertical characteristics of MLLJ are examined using the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA)-Interim and NCEP–NCAR reanalysis datasets. Special attention is paid to the spatial and temporal variation of the MLLJ peak height and peak speed

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Kaoru Sato and Motoyoshi Yoshiki

twice-daily operational radiosonde observations at Syowa Station) that the gravity wave energy at Syowa Station becomes large when the PNJ axis approaches the station. Yoshiki and Sato (2000) and Yoshiki et al. (2004) also showed evidence of gravity waves propagating energy downward in winter, which is consistent with the modeling results by SKT99 . Possible sources of gravity waves in the polar atmosphere were discussed by Sato (2000) . It is, however, generally difficult to examine upward

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Stanley G. Benjamin, Brian D. Jamison, William R. Moninger, Susan R. Sahm, Barry E. Schwartz, and Thomas W. Schlatter

using a 2007 version of the RUC, including both assimilation system and forecast model components. The observing systems considered in this study include seven primary wind/temperature observation types over the United States: radiosonde observations (raobs), aircraft ( Moninger et al. 2003 ), aviation routine weather report (METAR; surface), mesonet (automated surface observations from non-METAR networks), wind profilers ( Benjamin et al. 2004c ), velocity azimuth display (VAD) vertical wind

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Hui Liu, Jeffrey Anderson, Ying-Hwa Kuo, Chris Snyder, and Alain Caya

. When the distance between the observation and the state variable is larger than 1300 km, the impact of the observation goes to zero. This localization half-width distance is large enough to span the area of dependence of an RO refractivity observation, approximately 300–500 km around the GPS RO observation perigee locations in the troposphere ( Kursinski et al. 1997 ). The current version of the WRF ensemble data assimilation system can assimilate radiosonde observations, aircraft reports

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Yanjun Guo, Fuzhong Weng, Guofu Wang, and Wenhui Xu

1. Introduction Upper-air temperature is one of the essential climate variables measuring the atmospheric state and its long-term trend is an important indicator for climate change. Generally, upper-air temperature data are obtained from satellite remote sensing and in situ radiosonde observations. Since 1978, NOAA has launched a series of satellites with the Microwave Sounding Unit (MSU) and the Advanced Microwave Sounding Unit (AMSU) onboard. MSU and AMSU measure the radiance of at the top of

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Aiguo Dai, Junhong Wang, Peter W. Thorne, David E. Parker, Leopold Haimberger, and Xiaolan L. Wang

atmospheric water vapor content using various types of observations. Since the middle of the twentieth century, many countries have made routine observations of atmospheric humidity using balloon-borne radiosondes. These radiosonde humidity observations provide the only record that has high vertical resolution and is long enough for quantifying multidecadal changes in atmospheric water vapor, although other observations, such as surface humidity data ( Dai 2006 ; Willett et al. 2008 ) and recent

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Anna Agustí-Panareda, Anton Beljaars, Carla Cardinali, Iliana Genkova, and Chris Thorncroft

1. Introduction The West African monsoon provides most of the annual precipitation over the drought-prone Sahel. However, numerical weather prediction (NWP) precipitation forecasts are generally poor during the wet West African monsoon season from June to September, partly because of the lack of observations available. Before the African Monsoon Multidisciplinary Analysis (AMMA) field experiment in 2006, the radiosonde network was quite sparse and only a small amount of data was received via

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