Hydrological modelling on atmospheric grids: using graphs of sub-grid elements to transport energy and water - Sorbonne Université Access content directly
Journal Articles Geoscientific Model Development Year : 2023

Hydrological modelling on atmospheric grids: using graphs of sub-grid elements to transport energy and water

Abstract

Land surface models (LSMs) use the atmospheric grid as their basic spatial decomposition because their main objective is to provide the lower boundary conditions to the atmosphere. Lateral water flows at the surface on the other hand require a much higher spatial discretization as they are closely linked to topographic details. We propose here a methodology to automatically tile the atmospheric grid into hydrological coherent units which are connected through a graph. As water is transported on sub-grids of the LSM, land variables can easily be transferred to the routing network and advected if needed. This is demonstrated here for temperature. The quality of the river networks generated, as represented by the connected hydrological transfer units, are compared to the original data in order to quantify the degradation introduced by the discretization method. The conditions the sub-grid elements impose on the time step of the water transport scheme are evaluated, and a methodology is proposed to find an optimal value. Finally the scheme is applied in an off-line version of the ORCHIDEE (Organising Carbon and Hydrology In Dynamic Ecosystems) LSM over Europe to show that realistic river discharge and temperatures are predicted over the major catchments of the region. The simulated solutions are largely independent of the atmospheric grid used thanks to the proposed sub-grid approach.
Fichier principal
Vignette du fichier
gmd-16-2583-2023.pdf (6.96 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-04106435 , version 1 (25-05-2023)

Licence

Attribution

Identifiers

Cite

Jan Polcher, Anthony Schrapffer, Eliott Dupont, Lucia Rinchiuso, Xudong Zhou, et al.. Hydrological modelling on atmospheric grids: using graphs of sub-grid elements to transport energy and water. Geoscientific Model Development, 2023, 16, pp.2583-2606. ⟨10.5194/gmd-16-2583-2023⟩. ⟨insu-04106435⟩
34 View
36 Download

Altmetric

Share

Gmail Facebook X LinkedIn More