International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part Bl. Istanbul 2004
networks (Alsdorf and Lettenmaier, 2003). Indeed,
prediction of ungauged water resources is fast becoming
a well-defined and important problem in satellite
hydrology.
Therefore it is apparent that the use of remotely
sensed data is severely limited for most small-scale
basins with areas less than a few km2. Most hill-slope
scale processes, viz., 10-1000m? cannot benefit from the
current generation of satellite or radar data due to coarse
spatial resolution. However, medium sized basins, viz.,
10-100km^ can use most of the satellite and radar data
sets (with the exception of the 50km soil moisture).
Larger basins (100-10,000km^) are perfect locations for
use of satellite and radar data as they will have multiple
pixel coverage. Since these basins are "large", remotely
sensed data will help in "bridging" the existing (may be
insufficient) observations on the ground. In the future, as
technology improves, and satellite sensor resolutions
become higher («100m), smaller basins can also be
observed from space.
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