[A-CG42] Water and sediment dynamics from land to coastal zones

[ACG42-P01] Representing terrestrial water dynamics within Earth system modelling framework

*Dai Yamazaki¹ (1.Institute of Industrial Sciences, The University of Tokyo)

Keywords:Earth System Modelling, Terrestrial Water Dynamics

Within the framework of Earth System modelling, land sub-models usually represent water dynamics as vertical 1-dimentional processes to provide lower boundary conditions for the atmospheric model. In addition, river sub-models represent water transport along the river network to represent global hydrological cycle across atmosphere, land and oceans. Thus, terrestrial water dynamics has been represented as simplified “1D:vertical + 1D:along river” processes. While the actual terrestrial water dynamics is more complex, including horizontal dynamics such as flooding, surface flow, and sub-surface flow. They affect land-atmosphere interactions and global material cycles by changing surface water extent, moisture redistribution and vegetation type distribution, thus should be better represented in climate modelling. However, representing these detailed terrestrial water dynamics within Earth system model had been difficult because of the discrepancy of spatial scales. In very recent years, there are significant advancements in representing detailed terrestrial water dynamic such as flooding and hillslope moisture redistribution by utilizing sub-grid scale physics approaches, and also due to the development of high precision global topography datasets. Here, we review recent advances in global-scale terrestrial water dynamics modelling and discuss the potential applications in Earth system modelling.