H038-0023
Using GRACE estimates of groundwater storage changes in the Zhoushui river alluvial fan, Taiwan
Tuesday, 8 December 2020
Poster
Huang Chung-Chieh1, Hong-Ru Lin2, Jyun-Lin Chen3, Shao-Yang Huang3, Jet-Chau Wen4, Pat J.-F. Yeh5 and Ben Jarihani6, (1)National Yunlin University of Science and Technology, Douliou, Taiwan, (2)National Yunlin University of Science and Technology, Graduate School of Engineering Science and Technology, Douliou, Taiwan, (3)National Yunlin University of Science and Technology, Research Center for Soil and Water Resources and Natural Disaster Prevention (SWAN), Douliou, Taiwan, (4)National Yunlin University of Science and Technology, Department and Graduate School of Safety Health and Environmental Engineering, Douliou, Taiwan, (5)Monash University, Kuala Lumpur, Malaysia, (6)Commonwealth Scientific and Industrial Research Organisation - CSIRO, Brisbane, Australia
Abstract:
Since the successful launch of the Gravity Recovery and Climate Experiment (GRACE) on March 17
th, 2002, a number of scientists have adopted satellite gravimetry for the detection of variations on terrestrial water storage (TWS). Use of high-precision GRACE gravimetry presents advantages in hydrogeologic studies, such as providing accurate estimates of currents and gravity fields. Many studies have proven that the high-precision GRACE gravimetry can observe large-scale (over 50,000 km
2) variations in groundwater storage (GWS). However, relatively few studies conducted using satellite gravimetry have focused on scales smaller than 5,000 km
2.
The purpose of this study is to investigate the potential for using GRACE gravimetry to observe small-scale variations in GWS specifically, this paper presents a case study of the Zhoushui River alluvial fan (~2,560 km2) in central Taiwan as an example of how well GRACE data compare to field-based data for ascertaining small-scale variations in GWS. Field measurements of groundwater level in 52 observation wells (2002-2017) were used to analyze variations in GWS. Results of this field-based analysis were compared to results obtained using the GWS data (2002-2017) obtained by GRACE gravimetry. This comparison allowed us to evaluate the similarities and differences in both methods as well as to prove the feasibility of using GRACE gravimetry in small-scale regions. Results of our comparative analysis indicate that water resources in small watershed can be successfully managed using gravimetric data collected by GRACE satellite.
Keywords: Groundwater storage, GRACE, Alluvial fan
