Airborne Thermal Remote Sensing for Estimation of Groundwater Discharge to a River.
Traditional methods for studying surface water and groundwater interactions have usually been limited to point measurements, such as geochemical sampling and seepage measurement. A new methodology is presented for quantifying groundwater discharge to a river, by using river surface temperature data obtained from airborne thermal infrared remote sensing technology. The Hot Spot Analysis toolkit in ArcGIS was used to calculate the percentage of groundwater discharge to a river relative to the total flow of the river. This methodology was evaluated in the midstream of the Heihe River in the arid and semiarid northwest China. The results show that the percentage of groundwater discharge relative to the total streamflow was as high as 28%, which is in good agreement with the results from previous geochemical studies. The data analysis methodology used in this study is based on the assumption that the river water is fully mixed except in the areas of extremely low flow velocity, which could lead to underestimation of the amount of groundwater discharge. Despite this limitation, this remote sensing-based approach provides an efficient means of quantifying the surface water and groundwater interactions on a regional scale.
Institute of Water Sciences, Peking University, Beijing 100871, China.
Chuankun
C
Liu
Institute of Water Sciences, Peking University, Beijing 100871, China.
Jie
J
Liu
Institute of Water Sciences, Peking University, Beijing 100871, China.
Yue
Y
Hu
State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China.
Heshun
H
Wang
Institute of Water Sciences, Peking University, Beijing 100871, China.|School of Environmental Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, China.
Chunmiao
C
Zheng
D002681:China; D005618:Fresh Water; D060587:Groundwater; D058998:Remote Sensing Technology; D045483:Rivers