Abstract:
In this study, a framework to monitor the volumetric
fluctuation of the inland water body by the combination
of a bathymetry map, an optical satellite imagery
& multiple satellite altimetry measurements is presented.
In spite of the recent studies in monitoring water level
changes in lakes using satellite altimetry & optical satellite
imagery, it’s still evident that these methods are limited
to the water level, surface area and volume changes. However,
to effectively study the lakes, it’s important to quantify
the total lake volume. This hasn’t been possible as the
existing satellite methods cannot estimate the bathymetry
depth. The methodology was developed over Lake Victoria
during 1993–2016. The results indicate that the water
level, area, and volume of Lake Victoria decreased over
the past 23 years. The water level shows a slight decrease
(−0.005 m/year) of a total of −0.115 m from 1993 to 2016.
The changes in water level translates to a reduction in lake
area (−100 km2) and volume (−5 km3). Despite the inconsistent
changes in area and volume, significant reduction
occurred between 1998 and 2006 where (3484 km2) and
(122.87 km3) reduction in area and volumes respectively
were observed.
