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A. A. Tsonis

/no snow cover,clear skies/snow cover and clouds. Clouds are then classified as high or low broken clouds and overcast. Thescheme is tested for various weather situations. Comparison of the classification results with reports fromground synoptic stations and maps reflect an average accuracy of approximately 72%, and a higher accuracy(-.87%) when high or low broken clouds and overcast are considered as one class (i.e., clouds). Thedifferentiation between clouds and snow, or no snow-covered ground has

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A. Lemonsu, S. Bélair, J. Mailhot, and S. Leroyer

1. Introduction At high latitudes and under a cold winter climate, cities may be covered by snow for several months of the year. This is notably the case for most Canadian cities. During recent years, the Meteorological Service of Canada (MSC) put special emphasis on the representation and understanding of snow processes and their influence on radiation and energy exchanges at the surface in urban areas. In this context, the Montreal Urban Snow Experiment (MUSE) 2005 ( Lemonsu et al. 2008 ) has

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Robert C. Allen Jr., Philip A. Durkee, and Carlyle H. Wash

994 JOURNAL OF APPLIED METEOROLOGY VOLUME29Snow/Cloud Discrimination with Muifispectral Satellite MeasurementsROBERT C. ALLEN, JR.,* PHILIP A. DURKEE AND CARLYLE H. WASHDepartment of Meteorology, U.S. Naval Postgraduate School, Monterey, California(Manuscript received I 1 March 1989, in final form 6 December 1989) An algorithm is developed and evaluated for discriminating between clouds, snow-covered land

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Lawrence C. Nkemdirim

NOVEMBER 1978 L A W R E N C E C. N K E M D I R I M 1643A Comparison of Radiative and Actual Nocturnal Cooling Rates over Grass and Snow LAWRENCE C. NKEMDIRIHDepartment of Geography, The University of Calgary, Calgary, Canada T2N 1N4(Manuscript received 21 April 1978, in final form 30 June 1978)ABSTRACT Measured divergence of net nocturnal longwave flux between 1 and 3 m over a snow-covered field

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Steven D. Miller, Thomas F. Lee, and Robert L. Fennimore

Introduction Real-time maps of snow cover are extremely useful to weather forecasters, planners, and resource managers. There are numerous applications requiring knowledge of the cloud obscuration of snow-covered land or ice (especially sea ice), including search and rescue missions, aircraft icing, and military surveillance ( McCrone 2003 ) in support of ground forces. Satellite data have accounted for major improvements in the production of reliable global snow cover maps. Often, however

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Christopher L. Brest

reflectance of the target to its satellite-observed radiance. The visible and near-infraredreflectance were integrated into a measure ofalbedo by the use of a weighted average formula which incorporatesthe spectral refiectivity of the surface of interest and the spectral distribution of solar radiation. Three distinctformulae were employed for vegetated surfaces, nonvegetated surfaces, and snow-covered surfaces. Visible reflectance, near infrared reflectance, and albedo (for both snow-free and snow-cover

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Junsei Kondo and Takeshi Yamazaki

method has been developed. This model takes into account boththe heat balance at the snow surface and that of the entire snow cover and simultaneously predicts the snowsurface temperature and freezing depth. Observed or estimated incident radiation data are required for operationof the model. Calculated amounts of snowmelt and snow surface temperatures were in agreement with those observed.- Dependency of snowmelt on several parameters including maximum liquid water content, thermal

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Stephen H. Schneider and Robert E. Dickinson

underestimate of thedownward flux of solar radiation reaching the earth's surface. This underestimate is most pronounced inregions of persistent cloud cover and high surface aibedos--the snow- and ice-covered regions of the highlatitude zone, for example. Since the rate of snow melt (and thus snow aibedo) depends upon the downwardflux, neglect of multiple reflection is most serious in climatic models that predict snow and ice cover. Twosimple algebraic expressions to account for multiple reflections in

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D. G. Baker, R. H. Skaggs, and D. L. Ruschy

daily albedo of snow cover over sod, alfalfa, and bare soil was obtained over the course of 19winters. This period provided a wide range of snow depths (up to 61 cm), albedos (a maximum of 95% ), anddensities (from less than 40 to more than 350 kg m-3). The mean over-winter height of the sod was 4 to 6 cm,while the alfalfa ranged from 7 to 15 cm tall. It was found that the rate of increase of the albedo with increasing snow depth showed a marked decreaseonce the albedo reached about 70%. It was

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Terhikki Manninen, Emmihenna Jääskeläinen, and Aku Riihelä

(Montana and Colorado, respectively). Payerne (PAY) and Tõravere (TOR) are located in Europe (Switzerland and Estonia respectively). ALE, BAR, BOS, PAY, TOR, and FPE are seasonal snow sites, whereas DOM has permanent snow and ice cover. All measurements take place over open ground with no shadowing obstruction effects. Table 1. The BSRN sites used in the study ( König-Langlo et al. 2013 ; Driemel et al. 2018 ). 3. Methods a. Empirical formulation of diurnally varying snow albedo The solar zenith

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