Active Microwave Systems for Monitoring Drought Stress - Monitoring and Predicting Agricultural Drought: A Global Study - page 115

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Fig ure 8.2 Spatial drought pattern of an extreme winter drought that hit China in 1999 as
reflected in scatterometer data and gridded precipitation data. Left: difference of February
and March 1999 profile soil moisture to the 1992-2000 average derived from scatterometer
data; right: difference of February and March 1999 gridded precipitation (GPCC, 1998) to
th e 1992-2000 average.

lative effects of droughts. However, applications of radars in monitoring
drought stress have been limited due to the relative newness of radar tech-
nology, the lack of operational radar sensor systems, and the complex in-
teraction of radar waves with natural surfaces. Realistically, much more
research and preoperational demonstrations need to be carried out before
radars can be accepted as dependable information providers for drought
monitoring systems. Nevertheless, a greater understanding of the radar ca-
pabilities will lead to the more intelligent use of the SAR systems such as
RadarSat-2 (scheduled to be launched in 2005) or METOP (scheduled to
be launched in 2005) for operational drought monitoring.