Articles | Volume 13, issue 11
Hydrol. Earth Syst. Sci., 13, 2241–2251, 2009
https://doi.org/10.5194/hess-13-2241-2009
Hydrol. Earth Syst. Sci., 13, 2241–2251, 2009
https://doi.org/10.5194/hess-13-2241-2009

  26 Nov 2009

26 Nov 2009

Deriving a global river network map and its sub-grid topographic characteristics from a fine-resolution flow direction map

D. Yamazaki1, T. Oki1, and S. Kanae2 D. Yamazaki et al.
  • 1Institute of Industrial Science, University of Tokyo, Japan
  • 2Graduate School of Information Science and Engineering, Tokyo Institute of Technology, Japan

Abstract. This paper proposes an improved method for converting a fine-resolution flow direction map into a coarse-resolution river network map for use in global river routing models. The proposed method attempts to preserve the river network structure of an original fine-resolution map in the upscaling procedure, as this has not been achieved with previous upscaling methods. We describe an improved method in which a downstream cell can be flexibly located on any cell in the river network map. The improved method preserves the river network structure of the original flow direction map and allows automated construction of river network maps at any resolution. Automated construction of a river network map is helpful for attaching sub-grid topographic information, such as realistic river meanderings and drainage boundaries, onto the upscaled river network map. The advantages of the proposed method are expected to enhance the ability of global river routing models by providing ways to more precisely represent surface water storage and movement.

Download