Monitoring and validation of the lake/reservoir levels using satellite radar altimeter data in Indian sub-continent
Student name: Ms Ashima Jain
Guide: Dr P K Joshi
Year of completion: 2011
Host Organisation: Regional Remote Sensing Centre-North, NRSC, Indian Space Research Organisation (ISRO), Dept. of Spac
Supervisor (Host Organisation): Sh. D. Giri Babu
Abstract: Lake water has a dynamic behavior and its variations are an essential subject for
water resources and management. Most of the physical and ecological processes are
directly related with its fluctuation. The change in the level of lake-surface directly
indicates the water mass balance in the basin since they reflect water storage
variations. Space borne altimeters have been successfully used to measure the lakes
and reservoirs stages. Water level fluctuations were obtained from Envisat Radar
Altimeter (RA-2) and Jason-2 altimeter data using Geophysical Data Records (GDR)
coupled with in-situ measurements such as Full Reservoir Level (FRL). The ENVISAT
GDR products contain, over different types of surfaces, altimeter ranges derived from
the four specialized algorithms or retrackers. A validation study is necessary to assess
the performances of different retrackers’ derived water levels to monitor inland
waters. Therefore four test zones over different part of Indian sub-continent were
selected viz. Rana Pratap Sagar - one of the major dams in Rajasthan, Gandhi Sagar
and Bansagar in Madhya Pradesh, Hasdeo Bango in Chattisgarh. Comparison of the
performances was made for these retracking algorithms to deliver reliable water levels
for land hydrology. A multi-mission technique was applied to Rana Pratap Sagar,
Rajasthan which has made the conclusion that water level fluctuations can only be
determined accurately with Near Real Time (NRT) data but this area has seasonal
force by the rainy and dry climatic conditions in the region.
KEYWORDS: Geophysical Data Record (GDR), ENVISAT RA-2, JASON-2, Full
Reservoir Level (FRL), Retracking
