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Frédéric Tridon, Céline Planche, Kamil Mroz, Sandra Banson, Alessandro Battaglia, Joel Van Baelen, and Wolfram Wobrock

thermodynamics in the stratiform region. The vertical wind obtained from the DSD retrieval ( Fig. 8d ) and the relative humidity retrieved by the ARM Raman lidar are relevant in this context. Comparison of model results with profiling observations are challenging because a model cannot be expected to reproduce exact system evolution in space and time, and the representativeness of a single event time–height is unknown. One solution is to compare statistically the observations at SGP to a large number of

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Filipe Aires, Francis Marquisseau, Catherine Prigent, and Geneviève Sèze

, such as the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Terra and Aqua platforms or the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat geostationary satellite have been investigated. These new observations have shown large improvements in their cloud detection and the cloud property retrieval ( Ackerman et al. 1998 ; Frey et al. 2008 ; Derrien and Gléau 2010 ). Furthermore, active measurements from the Cloud–Aerosol Lidar with Orthogonal

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Carolyn A. Reynolds, Rolf Langland, Patricia M. Pauley, and Christopher Velden

themselves had relatively small impact. They also found that observations in the core of the TC sometimes led to large differences in the analysis, but only small forecast improvements. They attributed this to the fact that current model resolutions are insufficient to effectively use the TC core data, an issue also pointed out by Aberson (2008) . Studies have also looked at the impact of lidar observations on forecasts. Harnisch et al. (2011) found that, in the ECMWF system, differential absorption

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Daniel C. Hartung, Jason A. Otkin, Jonathan E. Martin, and David D. Turner

methods a. Instrumentation Interrogation of the 3D structure and evolution of the cold front draws upon a number of observational datasets. High spatial and temporal resolution surface observations from the Oklahoma Mesonet and Atmospheric Radiation Measurement (ARM) Surface Meteorological Observation System (SMOS) stations are employed, in addition to remote sensing observations taken from the Raman lidar and the Millimeter wavelength Cloud Radar (MMCR). In 2006, the Oklahoma

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Nicholas A. Gasperoni, Xuguang Wang, Keith A. Brewster, and Frederick H. Carr

1. Introduction With the increasing sophistication of data assimilation (DA) methods and accompanying numerical weather prediction (NWP) models, there is great potential to increase our understanding and forecasting accuracy of high-impact severe weather events. As operational NWP forecasts move toward grid resolutions that resolve convection explicitly, dense observations are needed in both space and time to be able to capture the small-scale and rapidly evolving features of such severe events

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David A. R. Kristovich, Neil F. Laird, and Mark R. Hjelmfelt

based on radar and in situ observations. Bound.-Layer Meteor. , 89 , 407 – 444 . Mayor , S. D. , 2001 : Volume imaging lidar observations and large-eddy simulations of convective internal boundary layers. Ph.D. thesis, University of Wisconsin—Madison, 177 pp . Melfi , S. H. , J. D. Spinhirne , S-H. Chou , and S. P. Palm , 1985 : Lidar observations of vertically organized convection in the planetary boundary layer over the ocean. J. Climate Appl. Meteor. , 24 , 806 – 821

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Bruce A. Wielicki, J.T. Suttles, Andrew J. Heymsfield, Ronald M. Welch, James D. Spinhirne, Man-Li C. Wu, David O'C. Starr, Lindsay Parker, and Robert F. Arduini

measurements found anomalously low absorption (i.e., high reflectance) for optically thick cirrus.More recently, Foot (1988) found mixed results comparing aircraft microphysical measurements with radiance observations of liquid-water clouds and reasonable agreement for an ice cloud case. The present work continues the effort to both measure and model the radiative properties of cirrus clouds.Aircraft microphysical, radiometric, and lidar measurements, along with satellite radiance measurementsare

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L. Cucurull, R. Atlas, R. Li, M. J. Mueller, and R. N. Hoffman

1. Introduction Observing system simulation experiments (OSSEs) provide a unique framework to evaluate the impact of current and proposed or future observing systems ( Atlas 1997 ; Atlas et al. 1985 ). While observing system experiments (OSEs) can be used to assess the value of existing observations, OSSEs enable a quantitative evaluation of proposed observing technologies. Different from the real-world scenario, the “truth” is known in the OSSE system, providing an effective technique to

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Tanya R. Peevey, Jason M. English, Lidia Cucurull, Hongli Wang, and Andrew C. Kren

the DA system. Both Atlas et al. (2015) and Ma et al. (2015) evaluated the impact of simulated wind lidar observations on forecast skill and found an improvement in the wind and mass fields, both in the extratropics and tropics. Moreover, Atlas et al. (2015) found that the short-term forecasts over the tropics were significantly reduced. OSSE studies have also evaluated the impact of rawinsondes globally for wind and temperature fields ( Privé et al. 2014a ) and dropsondes for tropical

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Maike Ahlgrimm and Richard Forbes

) are calculated from the 30-s Cloudnet retrieval of the two-channel microwave radiometer observations. Hourly samples with inferior quality observations of either surface radiation or hydrometeor profile are excluded from the evaluation. The target classification is only performed when both lidar and radar are available, and surface radiation measurements must be available for at least 50 out of 60 min within an hourly period. b. Model Data from the operational global ECMWF IFS model at the grid

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