Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 4.256 IF 4.256
  • IF 5-year value: 4.819 IF 5-year
    4.819
  • CiteScore value: 4.10 CiteScore
    4.10
  • SNIP value: 1.412 SNIP 1.412
  • SJR value: 2.023 SJR 2.023
  • IPP value: 3.97 IPP 3.97
  • h5-index value: 58 h5-index 58
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 99 Scimago H
    index 99
Volume 21, issue 2
Hydrol. Earth Syst. Sci., 21, 751-764, 2017
https://doi.org/10.5194/hess-21-751-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Hydrol. Earth Syst. Sci., 21, 751-764, 2017
https://doi.org/10.5194/hess-21-751-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 07 Feb 2017

Research article | 07 Feb 2017

Application of CryoSat-2 altimetry data for river analysis and modelling

Raphael Schneider1, Peter Nygaard Godiksen2, Heidi Villadsen3, Henrik Madsen2, and Peter Bauer-Gottwein1 Raphael Schneider et al.
  • 1Technical University of Denmark, Department of Environmental Engineering, 2800 Kgs. Lyngby, Denmark
  • 2DHI, 2970 Hørsholm, Denmark
  • 3National Space Institute, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark

Abstract. Availability of in situ river monitoring data, especially of data shared across boundaries, is decreasing, despite growing challenges for water resource management across the entire globe. This is especially valid for the case study of this work, the Brahmaputra Basin in South Asia. Commonly, satellite altimeters are used in various ways to provide information about such river basins. Most missions provide virtual station time series of water levels at locations where their repeat orbits cross rivers. CryoSat-2 is equipped with a new type of altimeter, providing estimates of the actual ground location seen in the reflected signal. It also uses a drifting orbit, challenging conventional ways of processing altimetry data to river water levels and their incorporation in hydrologic–hydrodynamic models. However, CryoSat-2 altimetry data provides an unprecedentedly high spatial resolution. This paper suggests a procedure to (i) filter CryoSat-2 observations over rivers to extract water-level profiles along the river, and (ii) use this information in combination with a hydrologic–hydrodynamic model to fit the simulated water levels with an accuracy that cannot be reached using information from globally available digital elevation models (DEMs) such as from the Shuttle Radar Topography Mission (SRTM) only. The filtering was done based on dynamic river masks extracted from Landsat imagery, providing spatial and temporal resolutions high enough to map the braided river channels and their dynamic morphology. This allowed extraction of river water levels over previously unmonitored narrow stretches of the river. In the Assam Valley section of the Brahmaputra River, CryoSat-2 data and Envisat virtual station data were combined to calibrate cross sections in a 1-D hydrodynamic model of the river. The hydrologic–hydrodynamic model setup and calibration are almost exclusively based on openly available remote sensing data and other global data sources, ensuring transferability of the developed methods. They provide an opportunity to achieve forecasts of both discharge and water levels in a poorly gauged river system.

Publications Copernicus
Download
Short summary
We use water level observations from the CryoSat-2 satellite in combination with a river model of the Brahmaputra River, extracting satellite data over a dynamic river mask derived from Landsat imagery. The novelty of this work is the use of the CryoSat-2 water level observations, collected using a complex spatio-temporal sampling scheme, to calibrate a hydrodynamic river model. The resulting model accurately reproduces water levels, without precise knowledge of river bathymetry.
We use water level observations from the CryoSat-2 satellite in combination with a river model...
Citation
Share