Potential of Multi-mission Satellite Altimetry Observations and
Hydrodynamic Model to Establish Virtual Gauging Network in Sparsely
Gauged Basin
Abstract
Researchers dealing with flood hazard and risk assessment typically
refer to available in-situ gauging stations for the calibration and
validation of hydrological and hydrodynamic (HD) models. However, lack
of dense gauging data such as stage-discharge relationship (rating
curves) results in higher uncertainty in hydrological studies. The
multi-mission satellite altimetry observations are capable since long
time to monitor continental water bodies at regular interval. In this
study, combined use of hydrodynamic model and satellite altimetry data
has been exploited for establishing virtual gauging network in
flood-prone sparsely gauged river basin. The virtual gauging stations
were established at locations where ground tracks of various altimeters
(Jason-2/3, SARAL/AltiKa, and Sentinel-3A/3B) cross the river channel.
Rating curves were generated at these virtual stations using calibrated
and validated HD model. High agreement between the simulated and
altimetry-based water levels at virtual stations showed the potential of
satellite altimetry data for the multi-site validation of HD model and
constructed rating curves. The availability of water level time series
and rating curves at multiple virtual locations in addition to existing
in-situ physical gauging stations provides an opportunity to expand
gauging network in sparsely gauged basin. Thus, the proposed framework
may open new perspectives for enhancing river flow dynamic studies
considering upcoming satellite missions like SWOT which will ensure more
observations in future.