Inland Water Bodies Monitoring using Satellite Altimetry over Indian Region
Other literature type
Dubey, A. K.
Gupta, P. K.
Singh, R. P.
(issn: 2194-9034, eissn: 2194-9034)
Satellite altimetry for inland water applications has evolved from investigation of water height retrieval to monitoring since last two
decades. Altimetry derived reservoir/ river levels can subsequently be used to deal with key inland water resources problems such as
flood, rating curve generation for remote locations, reservoir operations, and calibration of river/lake models. In this work 29 inland
water bodies were selected over Indian region to monitor from satellite altimetry. First cut selection of potential water bodies was
based on availability of altimeter tracks and geographic locations. Then feasibility study was carried out to check the potential of
availability of in-situ measurement and scope of GPS survey for final selection. An algorithm is proposed and tested for the waterlevel
retrieval over the Ukai Reservoir which fulfil all the necessary requirements. The methodology is based on averaged high rate
waveforms, modified retracker and range corrections. The results were then validated with the GPS survey and in-situ tide gauge
dataset. SARAL derived water-level information for six different retrackers were compared with the in-situ tide-gauge dataset
installed close to the Ukai Dam. Averaged high rate waveforms were analysed for better performance, i.e. single 40 Hz, and multiple
40-Hz. A field trip was conducted on 17th January 2014, same day on the SARAL pass, using two Dual frequency GPS instruments.
New improved retracker work best with overall RMSE within the range of 8 cm. The results supports that AltiKa dataset can be
utilized for more accurate water level information over inland water bodies.