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Masanori Saito, Ping Yang, Norman G. Loeb, and Seiji Kato

1. Introduction Snow plays an essential role in the surface radiation balance as well as the hydrological cycle through complex snow–atmosphere feedbacks ( Randall et al. 1994 ). In particular, surface albedo is one of the main regulators of the radiative balance over snow-covered areas. Even with a persisting snow cover, changes in snow albedo affect air temperature, snow-cover extent, and the melting of snow. Therefore, an accurate snow albedo model in conjunction with a physical snow

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Sujay V. Kumar, Christa D. Peters-Lidard, David Mocko, and Yudong Tian

1. Introduction The importance of snow cover estimates for a variety of hydrologic and water resources applications is well recognized ( Barnett et al. 2005 ). Through its high albedo and low thermal conductivity, snow cover exerts strong influences on land atmosphere energy exchanges and on the evolution of atmospheric conditions ( Cohen and Entekhabi 1999 ). The seasonal and interannual variability of snow cover affects the seasonal freeze and thaw of the ground and the timing and duration of

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David A. Robinson and George Kukla

16263OURNAL OF CLIMATE AND APPLIED METEOROLOGYVOLUME 23Albedo of a Dissipating Snow Cover'DAVID A. ROBINSON AND GEORGE KUKLALamoni-Doherly Geological Observatory, Columbia University, Pa!isades, NY 10964(Manuscript received 18 June 1984, in final form 29 September 1984)ABSTRACTAlbedos of surfaces covered with 50 cm of fresh dry snow following a major U.S. East Coast storm on11-12 February 1983 ranged from 0.20 over a mixed coniferous forest to 0.80 over open farmland. As thesnow cover

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Shinji Matsumura, Xiangdong Zhang, and Koji Yamazaki

1. Introduction Summer Arctic sea ice extent (SIE) has declined rapidly during recent decades (e.g., Serreze et al. 2007 ; Comiso et al. 2008 ), while spring Eurasian snow cover extent (SCE) has decreased over the past several decades (e.g., Groisman et al. 2006 ; Brown et al. 2010 ; Derksen and Brown, 2012 ). In seasonality, the Eurasian subarctic becomes snow free in early summer, while the Arctic Ocean remains continually covered by a large area of sea ice until late summer. This lagged

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A. S. Bamzai and J. Shukla

especially the variations in rainfall over India are significantly correlated with the tropical sea surface temperature and the Eurasian snow cover anomalies. Of all the varying surface conditions, snow cover experiences the largest spatiotemporal fluctuations, thus it has the potential to influence the radiation and energy budget of the lower atmosphere through the effect of heating of the land surface and the diabatic heating of the atmosphere. The combination of land–sea temperature contrast and

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Emanuel Dutra, Pedro Viterbo, Pedro M. A. Miranda, and Gianpaolo Balsamo

1. Introduction Accurate simulations of the snow cover strongly impact on the quality of weather and climate prediction as the absorption of solar radiation at the land–atmosphere interface is modified by a factor up to 4 in response to the presence of snow (albedo effect) ( Viterbo and Betts 1999 ). Changes in snow cover modify the surface albedo, which then feedbacks to surface temperature ( Groisman et al. 1994 ). In northern latitudes and mountainous regions, snow also acts as an important

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Thomas Marke, Ulrich Strasser, Florian Hanzer, Johann Stötter, Renate Anna Irma Wilcke, and Andreas Gobiet

1. Introduction Mountain ecosystems are known to be particularly vulnerable to climate change ( EEA 2012 ). To investigate climate change effects in Alpine regions, scenario simulations represent suitable tools in a wide range of applications ( Mauser and Ludwig 2002 ), the modeling of future climate and natural snow cover being important examples ( Liston 2004 ; Strasser 2008 ; Strasser and Marke 2010 ). Investigating potential changes in the spatial and temporal evolution of the Alpine

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Konstantin V. Khlopenkov and Alexander P. Trishchenko

parameters (the R score and the T score) are analyzed. If both are smaller than zero, then the pixel is considered to be clear-sky snow, and the processing jumps to the thin cirrus test (described below). Otherwise, the pixel is considered to be snow covered and cloud contaminated, and undergoes additional cloud tests. If no snow is detected in the first stage, then the pixel is considered to be potentially cloud contaminated and undergoes additional tests, beginning with the simple ratio test. 6

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Steven J. Fletcher, Glen E. Liston, Christopher A. Hiemstra, and Steven D. Miller

Earth Observing System (EOS) (AMSR-E) on the Aqua satellite. One of the products available from MODIS is a snow cover mask. This product is at a resolution of 500 m, which is useful in constraining snow evolution models like SnowModel that can run at high spatial and temporal resolution. However, snow cover is not a model variable but a binary function of the state variable: snow water equivalent (SWE). A problem with assimilating snow cover observations is that these are not a unique function of

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Susan Frankenstein, Anne Sawyer, and Julie Koeberle

1. Introduction Water stored in snowpacks and soils in the western United States is particularly important for natural ecosystems, public consumption, and industry because snowmelt accounts for approximately 80% of the soil moisture in semiarid environments in the western United States ( Marks and Winstral 2001 ). The intricate process of snow cover depletion and soil moisture recharge is spatially and physically complex, and an assessment of its behavior is essential for water balance

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