H004-0009
Global 5-arcmin Resolution Water Resource Assessment Using the H08 Global Hydrological Model with the Inter-grid Water Transfer Function
Monday, 7 December 2020
Poster
Keisuke Doi, Tokyo Institute of Technology, Tokyo, Japan, Menaka Revel, Institute of Industrial Science, University of Tokyo, Tokyo, Japan, Naota Hanasaki, National Institute for Environmental Studies, Ibaraki, Japan and Shinjiro Kanae, Tokyo Institute of Technology, Department of Civil and Environmental Engineering, Tokyo, Japan
Abstract:
For a more accurate understanding of the impact of climate change and human activities on the hydrological cycle, a high-resolution global water resource assessment is necessary. The global hydrological models were mainly used in spatial resolution of 1 degree or 0.5 degree because computational resources and functions required for high-resolution modeling were insufficient. However, some global hydrological models capable of high-resolution simulation have been developed in recent years. For example, functions such as inter-grid water transfer and medium-sized reservoir operation, which are essential for high-resolution simulations, are available in the latest version of global hydrological model H08. H08 is a model developed to quantitatively evaluate the influence of human activities on the global hydrological cycle, which enables identification of the water abstraction source of each water demand sector for agricultural water, industrial water and domestic water.
In this study, we conducted a series of global hydrological simulations at spatial resolution of 5 minutes and 0.5 degrees in H08. By comparing the model responses, we clarify the differences in water abstraction sources caused by the gap of the availability of renewable water sources in surface water and groundwater depending on spatial resolution of the model. Furthermore, we investigated how the inter-grid water transfer function would mitigate water stress in high water demand cities as a step to enable city-scale water resource assessment. As a result, we found that there were some points need to be improved in inter-grid water transfer scheme for more accurate modelling, although its water stress mitigation effect was shown in some places. We expect that the findings in this study is going to be a crucial step towards the development of a locally relevant high-resolution global hydrological model.
