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Fatima Karbou, Elisabeth Gérard, and Florence Rabier

regressions and empirical models ( Weng et al. 2001 ; Grody 1988 ) has been used in NWP and has facilitated the assimilation of AMSU channels over land. The effectiveness of these models depends on the input parameters about the surface, for which a global analysis does not always exist. To date, observations are more intensively used over sea than over land thanks to effective sea emissivity models ( Deblonde and English 2000 ; Guillou et al. 1998 ; Prigent and Abba 1990 ; Guissard and Sobieski 1987

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Curtis H. Marshall, Kenneth C. Crawford, Kenneth E. Mitchell, and David J. Stensrud

a spatial domain characterized by widely varying climate and land use regimes for extended periods of time, using the unique observations provided by the Oklahoma Mesonet ( Brock et al. 1995 ). The Oklahoma Mesonet is a high-resolution hydrometerological observing network covering the state of Oklahoma, which measures near-surface and subsurface fields at a spatial resolution ideal for verification of mesoscale models ( Fig. 1 ). The domain spans a wide contrast of land surface and climate

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Fatima Karbou, Florence Rabier, Jean-Philippe Lafore, Jean-Luc Redelsperger, and Olivier Bock

information content, gave a valuable description of the temperature and humidity at different levels in the atmosphere. The use of these measurements in NWP has led to substantial progress being made, but more effort is needed to assimilate many more observations in a wide range of atmospheric situations (clear, cloudy) and with a variety of surface conditions (ocean, land, snow, etc.). However, many issues are still to be addressed, in particular, the assimilation of observations in the presence of

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Louis Michael Schoenberger

DECEMBER 1986 LOUIS MICHAEL SCHOENBERGER 127Mesocale Features of the Michigan Land Breeze Using PAM lI Temperature Data LOUIS MICHAEL SCHOENBERGERUniversity of Chicago, Cloud Physics Laboratory, Chicago, IL 60637(Manuscript received 28 December 1985, in final form 21 July 1986) ABSTRACT During the period 16-20 December 1983, the northern United States was enduring a record-breaking coldair outbreak

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Thomas F. Lee

's)Advanced Very High Resolution Radiometer are eomposited to improve the depiction of airborne dust overcoastlines. On IR images, wind-raised dust stands out well against heated land surfaces. Once advected overocean, however, dust on IR images can not be easily distinguished from the cool surface. The situation is reversedon visible images: dust contrasts well with dark ocean backgrounds but poorly with bright land surfaces. Toillustrate the optimal use of both data types, a composite image juxtaposes

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Gary J. Jedlovec, Udaysankar Nair, and Stephanie L. Haines

contribution to damage surveys conducted by the NWS. The relationship between land cover type and the ability to detect tornado damage tracks in the satellite imagery is explored using land cover datasets, satellite imagery, and a satellite-derived vegetation index. 2. Background a. The SPoRT center In 2002, NASA established the SPoRT Center at Marshall Space Flight Center in Huntsville, Alabama, as a vehicle to transition unique observing, modeling, and data assimilation capabilities (developed under the

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Nicole P. Kurkowski, David J. Stensrud, and Michael E. Baldwin

, the LAI is assigned a constant value of 1 in the Eta Model and only the vegetation fraction is allowed to vary in time and space. Other land surface models allow both parameters to vary. Currently, the NCEP Eta Model uses a 0.144° (approximately 14 km) resolution monthly database for vegetation fraction, based upon a 5-yr climatology ( Black et al. 1997 ) developed at the National Environmental Satellite, Data, and Information Service (NESDIS). The monthly vegetation fraction values apply to the

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Richard M. Hodur and Bogumil Jakubiak

of these experiments. 2. Objective and approach The objective of this study is to address the extent to which different physical parameterizations and different treatments of the land/surface in a high-resolution NWP mesoscale model lead to improvements in the prediction of surface and near-surface weather conditions in Poland, including precipitation forecasts. Our approach is to use the atmospheric components of COAMPS, run forecasts over Poland for selected time periods using the control

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Clifford F. Mass, Jeffrey Baars, Garrett Wedam, Eric Grimit, and Richard Steed

interpolation using only land (water) MOS locations for land (water) grid points. An optimal bias removal scheme for forecast grids should have a number of characteristics. It must be robust and applicable to any type of terrain. It must work for a variety of resolutions and particularly for grid spacings at which mesoscale models will be run in the near future (1–10 km). It should be capable of dealing with regions of sparse data, yet also be able to take advantage of higher data densities when they are

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Rebecca E. Morss and F. Martin Ralph

predicting when the front would reach the coast. The gray front is taken from the official NWS surface analysis. The black front, dashed trough axis, and SLP contours are from a subjective analysis created using all operational and CALJET experimental observations (including P-3 observations). Wind barbs over ocean (except P-3 observations) show winds below 900 mb derived from Geostationary Operational Environmental Satellite (GOES) data. Wind barbs over land and near the coast show surface winds from

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