Satellite-Monitored Snow Cover in the Climate System - Satellite-based Applications on Climate Change - page 176

Chapter 12
Satellite-Monitored Snow Cover
in the Climate System
Li Xu
Abstract Snow cover plays an important role at climate system. Before the era of
“satellite meteorology,” traditional sources of snow observations were usually
obtained from ground-based meteorological networks, in which only the presence
or absence of snow along with snow depth is measured on a daily basis. Given the
scarcity of ground-based, in situ stations, it is difficult to adequately capture the
spatial variability of snow cover, particularly in remote, and difficult to access
regions such as polar region and Tibetan Plateau. The remote sensing from the
satellite provides an excellent method to monitor and observed global snow-cover
distribution and evolution. In this chapter, we reviewed the role of snow in climate
system, satellite snow observation and monitoring, snow-climate interaction, and
snow-atmosphere coupling strength.
12.1 The Role of Snow Cover in the Climate System
As a key component of the cryosphere, snow cover modifies the thermal
characteristics of land surfaces to modulate energy and moisture exchange with
the atmosphere above it (Cohen and Rind 1991 ). Because of their strong thermal
forcing to the lower atmosphere, snow-cover anomalies potentially play an impor-
tant role in climate fluctuations and predictability. For instance, observational
studies have even found a significant connection between snow anomalies over
the Eurasia and the remote Asian monsoon (Bamzai and Shukla 1999 ; Xu and Li
2010 ; Xu et al. 2009 ). Various GCM modeling studies (Bamzai and Marx 2000 ;