Estimation of river channel bathymetry using a global river model and satellite altimetry

2019 Fiscal Year Final Research Report

• Project/Area Number: 16H06101
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Hydraulic engineering
• Research Institution: The University of Tokyo (2017-2019); Japan Agency for Marine-Earth Science and Technology (2016)
• Principal Investigator: YAMAZAKI Dai 東京大学, 生産技術研究所, 准教授 (70736040)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 全球河川モデル / 衛星高度計 / 河川地形 / データ同化

Outline of Final Research Achievements

In this study, we developed a method to estimate river channel bathymetry by combining a global river model with a satellite altimeter.
First, it was necessary to significantly improve the accuracy of the hydro-topography data. We first developed the world's most accurate global elevation data MERIT DEM by removing multiple error components. We also construct a high-precision global river data MERIT Hydro by integrating various water area maps. As a result, the reliability of floodplain topographical parameters and river channel width parameters of the global river model has been significantly improved, and error information of water surface elevation can be used for estimating channel depth parameters.
Then, we developed an algorithm that optimizes the channel depth parameter so as to reduce the water surface elevation error. River depth estimation experiments in the Amazon basin confirmed the effectiveness of the river depth estimation.

Free Research Field

水文学

Academic Significance and Societal Importance of the Research Achievements

本研究で開発した高精度の水文地形データMERIT DEMとMERIT Hydroは、全球河川モデルの高度化に限らず、地球科学分野の多様な研究に使われる基盤データとなった。202年6月現在、のべ2000以上の研究者にデータを提供し、多様な研究に活用されている。
河道深さの最適化による全球河川モデルの高度化は、洪水リスク管理や気候変動予測など様々な社会実装につながると期待される。