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Laurent Menut and Bertrand Bessagnet

1. Introduction For analysis or forecast cases, one of the best ways to improve the results of a chemistry transport model is to better represent the physics and chemistry processes. Another way is to modify the trajectory by “assimilating” observations. Data assimilation consists of using hybridization methods of measurement data and modeling results to constraint the model prediction as close as possible to the observed data. The concept follows a simple principle whatever the studied

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Jinyi Hou and Ping Wang

between subgrids of successive radar fields. The area-based approaches extrapolate the radar image and produce a forecast using the motion vectors. The advantage of area-based nowcasting approaches is that they can provide accurate motion vector within each grid. The statistical and probability approaches aim at providing a measure of uncertainty in nowcasting. The statistical approaches (e.g., Xu et al. 2005 ; Seed 2003 ; Fox and Wikle 2005 ) represent atmospheric evolution using statistical

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Xin Zhang, Ying-Hwa Kuo, Shu-Ya Chen, Xiang-Yu Huang, and Ling-Feng Hsiao

RO soundings are currently being used at several global operational NWP centers, including the National Centers for Environmental Prediction (NCEP; Cucurull and Derber 2008 ), the European Centre for Medium-Range Weather Forecasts (ECMWF; Healy 2008 ), the Met Office (UKMO; Rennie 2010 ), and Météo-France ( Poli et al. 2009 ). Because of the success of COSMIC, U.S. agencies and Taiwan have decided to move forward with a follow-up RO mission [called Formosa Satellite Mission 7 (FORMOSAT-7

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Yinan Hu, Faruk Uysal, and Ivan Selesnick

algorithm can also attenuate the ground clutters in the absence of wind turbines. Table 3. Summary of changes made and their effects. The proposed algorithm is a promising approach in mitigating WTC, thus helping to improve weather analyses and forecasts. The adaptive selection of algorithm parameters for optimization is still an active research topic and requires further investigation. Acknowledgements This work was supported by ONR under Grant N00014-15-1-2314 and by the NSF under Grant CCF-1525398

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Do-Seong Byun and Deirdre E. Hart

adjustment methods of monthly variability in tidal current harmonic constants (in Korean) . Ocean Polar Res. , 33 , 309 – 319 , doi: 10.4217/OPR.2011.33.3.309 . Byun, D.-S. , and Wang X. H. , 2005 : The effect of sediment stratification on tidal dynamics and sediment transport patterns . J. Geophys. Res. , 110 , C03110 , doi: 10.1029/2004JC002459 . Byun, D.-S. , and Cho C. W. , 2009 : Exploring conventional tidal prediction schemes for improved coastal numerical forecast modeling . Ocean

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Nicolas Gaussiat, Robin J. Hogan, and Anthony J. Illingworth

supercooled water with an LWP of about 20 g m −2 , but their presence in the liquid rather than the ice phase can lead to shortwave flux changes of about 100 W m −2 . Accurate observations of liquid water path are needed to evaluate the representation of liquid water clouds in global circulation models (GCMs) used for forecasting future climate and for numerical weather prediction (NWP). In most operational NWP models, production of rain by collision and coalescence is parameterized by an autoconversion

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William E. Lewis, Eastwood Im, Simone Tanelli, Ziad Haddad, Gregory J. Tripoli, and Eric A. Smith

1. Introduction Tropical cyclones (TCs) are among the most devastating natural phenomena on earth, capable of spreading destruction and loss of life across wide geographical areas (e.g., Beven 2006 ). While the difficulties surrounding TC forecasting are well known ( Rappaport et al. 2009 ), the more fundamental issue of observing the cyclone is itself problematic. This is important because, aside from providing clues to forecasters on short-term intensity change ( Cecil and Zipser 1999

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Scott D. Rudlosky, Michael J. Peterson, and Douglas T. Kahn

present sensors match the GLM performance throughout the GLM domain, so data from multiple lightning detection networks have been used for GLM preparation. National Weather Service (NWS) forecasters are most familiar with data from ground-based lightning detection networks because they have had access to the National Lightning Detection Network (NLDN) data over the contiguous United States (CONUS) since the early 1990s. Outside CONUS (OCONUS) forecasters have relied on data from the World Wide

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P. C. Meyers, L. K. Shay, and J. K. Brewster

1. Introduction Coupled oceanic and atmospheric models for prediction of hurricane intensity and structure change are used for public advisories by forecasters and government officials, who rely on the most advanced weather forecasting systems to prepare for landfall ( Marks and Shay 1998 ). Over the past decade, it is increasingly clear that ocean models must include realistic initial conditions to simulate not only the oceanic response to hurricane forcing ( Price et al. 1994 ; Sanford et al

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Samuel R. Webb, Nigel T. Penna, Peter J. Clarke, Stuart Webster, Ian Martin, and Gemma V. Bennitt

1. Introduction The provision of measurements of atmospheric water vapor is a key requirement in meteorology and climate studies, with the highly variable spatial and temporal distribution of water vapor directly impacting precipitation patterns and energy transfer in the atmosphere. To improve the ability of numerical weather prediction (NWP) models to forecast precipitation, accurate atmospheric water vapor measurements are required for assimilation, particularly in otherwise data

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