Paper/Poster/Presentation Title
Keywords
Evapotranspiration, METRIC, Soil water content, Cosmic-ray neutron probe, Remote sensing
Start Date
25-6-2018 2:00 PM
End Date
25-6-2018 3:20 PM
Abstract
Evapotranspiration (ET) is an important component of the hydrological cycle but it is often poorly constrained boundary condition for understanding coupled surface and groundwater hydrologic modeling (SW-GW). Given this importance, multiple studies have explored the relationship between ET and different state variables. However, the spatial aspects of these relationships have not been sufficiently studied given the paucity of ET data until recent remote sensing products. In this study, the spatial relationship between ET and two state variables (i.e. water table depth and soil moisture) have been explored in central Nebraska. To investigate this relationship remote and proximal sensing data was combined with in-situ sensor data over 2 years. Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) method was applied to Landsat images to estimate daily ET. Roving and stationary cosmic-ray neutron probes (CRNP) were used to create a spatiotemporal soil moisture product. Groundwater wells were used to make water table maps. For days with available ET maps, the relationship between ET and abovementioned state variables was explored. In general, results indicate a stronger relationship between ET and soil moisture as compared to ET and groundwater. Though more studies are needed, the outcomes here helped us to identify the state variables which are more important in SW-GW processes. In addition, estimation of simple statistical relationships between disparate spatial maps of ET and continuous state variables will be useful in generating spatiotemporal products needed by future SW-GW models.
Exploring the Spatial Connection Between Groundwater, Soil Moisture and Evapotranspiration in Platte River Basin in Nebraska
Evapotranspiration (ET) is an important component of the hydrological cycle but it is often poorly constrained boundary condition for understanding coupled surface and groundwater hydrologic modeling (SW-GW). Given this importance, multiple studies have explored the relationship between ET and different state variables. However, the spatial aspects of these relationships have not been sufficiently studied given the paucity of ET data until recent remote sensing products. In this study, the spatial relationship between ET and two state variables (i.e. water table depth and soil moisture) have been explored in central Nebraska. To investigate this relationship remote and proximal sensing data was combined with in-situ sensor data over 2 years. Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) method was applied to Landsat images to estimate daily ET. Roving and stationary cosmic-ray neutron probes (CRNP) were used to create a spatiotemporal soil moisture product. Groundwater wells were used to make water table maps. For days with available ET maps, the relationship between ET and abovementioned state variables was explored. In general, results indicate a stronger relationship between ET and soil moisture as compared to ET and groundwater. Though more studies are needed, the outcomes here helped us to identify the state variables which are more important in SW-GW processes. In addition, estimation of simple statistical relationships between disparate spatial maps of ET and continuous state variables will be useful in generating spatiotemporal products needed by future SW-GW models.
Stream and Session
E1: Coupled Surface-Subsurface Hydrologic Modelling