JpGU-AGU Joint Meeting 2017

講演情報

[EE] ポスター発表

セッション記号 M (領域外・複数領域) » M-ZZ その他

[M-ZZ40] [EE] Sustainable global groundwater management for human security

2017年5月22日(月) 15:30 〜 17:00 ポスター会場 (国際展示場 7ホール)

コンビーナ:Yoshihide Wada(NASA Goddard Institute for Space Studies)、谷口 真人(総合地球環境学研究所)、Naota Hanasaki(NIES National Institute of Environmental Studies)、Yadu N Pokhrel(Michigan State University)

[MZZ40-P03] On the thresholds of withdrawal-to-availability ratio: a perspective from a global hydrological simulation including groundwater

*Hanasaki Naota1 (1.国立環境研究所)

キーワード:water resources

Withdrawal to availability ratio (WTA) is a widely accepted empirical index to express water stress in the world. It accompanies two empirical thresholds or the regions where WTA exceeds 0.2 and 0.4 are categorized as medium and high water stress respectively, but the rationale of these thresholds has been little explained. Here we show these thresholds are linked with physical water scarcity using a state of the art global hydrological model. The model enables us to simulate global water supply and demand at the spatial resolution of 0.5°×0.5° at a daily temporal interval with distinction of seven water sources including groundwater. From the simulation results, we obtained the relationship between WTA and the fraction of water abstraction from local and renewable sources to all (FLRE). We found that when WTA exceeds 0.2 and 0.4, FLRE shows a sudden drop in FLRE or the regions require additional non-local and/or nonrenewable water sources. The results support the general validity of WTA and the threshold as an index to assess water scarcity. At the same time, they also call the users attention that considerable spread between WTA and FLRE: WTA could be a surrogate of FLRE in limited extent