Abstract from SIR 2017-5079: This report documents methodology and results of a study to evaluate groundwater discharge by evapotranspiration (GWET) in sparsely vegetated areas of Amargosa Desert and improve understanding of hydrologic-continuum processes controlling groundwater discharge. Evapotranspiration and GWET rates were computed and characterized at three sites over 2 years using a combination of micrometeorological, unsaturated zone, and stable-isotope measurements. One site (Amargosa Flat Shallow [AFS]) was in a sparse and isolated area of saltgrass (Distichlis spicata) where the depth to groundwater was 3.8 meters (m). The second site (Amargosa Flat Deep [AFD]) was in a sparse cover of predominantly shadscale (Atriplex confertifolia) where the depth to groundwater was 5.3 m. The third site (Amargosa Desert Research Site [ADRS]), selected as a control site where GWET is assumed to be zero, was located in sparse vegetation dominated by creosote bush (Larrea tridentata) where the depth to groundwater was 110 m. Results indicated that capillary rise brought groundwater to within 0.9 m (at AFS) and 3 m (at AFD) of land surface, and that GWET rates were largely controlled by the slow but relatively persistent upward flow of water through the unsaturated zone in response to atmospheric-evaporative demands. Greater GWET at AFS (50 ± 20 millimeters per year [mm/yr]) than at AFD (16 ± 15 mm/yr) corresponded with its shallower depth to the capillary fringe and constantly higher soil-water content. The stable-isotope dataset for hydrogen (δ2H) and oxygen (δ18O) illustrated a broad range of plant-water-uptake scenarios. The AFS saltgrass and AFD shadscale responded to changing environmental conditions and their opportunistic water use included the time- and depth-variable uptake of unsaturated-zone water derived from a combination of groundwater and precipitation. These results can be used to estimate GWET in other areas of Amargosa Desert where hydrologic conditions are similar.

Selected evapotranspiration data were collected from 7/5/2011 to 1/1/2017 at the Amargosa Desert Research Site (ADRS, https://nevada.usgs.gov/adrs/) in support of ongoing research to improve the understanding of hydrologic and contaminant-transport processes in arid environments. The data presented in this data release includes 30-minute and daily evapotranspiration and associated energy-balance fluxes, precipitation, soil water content, air and soil temperature, wind speed and direction, humidity, and photosynthetically active radiation. Data methods follow those described in Moreo and others (2017). This is the third in a series of three releases of evapotranspiration data, which has been measured continuously at the ADRS since 2002.

Selected evapotranspiration data were collected from 7/5/2011 to 1/1/2017 at the Amargosa Desert Research Site (ADRS, https://nevada.usgs.gov/adrs/) in support of ongoing research to improve the understanding of hydrologic and contaminant-transport processes in arid environments. The data presented in this data release includes 30-minute and daily evapotranspiration and associated energy-balance fluxes, precipitation, soil water content, air and soil temperature, wind speed and direction, humidity, and photosynthetically active radiation. Data methods follow those described in Moreo and others (2017). This is the third in a series of three releases of evapotranspiration data, which has been measured continuously at the ADRS since 2002.

This data release supports U.S. Geological Survey Scientific Investigations Report 2023-5106, Groundwater Discharge by Evapotranspiration from the Amargosa Wild and Scenic River and Contributing Areas, Inyo and San Bernardino Counties, California. Geospatial datasets presented are two polygon shapefiles representing the groundwater discharge areas and evapotranspiration units for the Amargosa Wild and Scenic River and contributing areas, and a raster dataset representing the vegetation index corresponding to the vegetated evapotranspiration unit.

This data release supports U.S. Geological Survey Scientific Investigations Report 2023-5106, Groundwater Discharge by Evapotranspiration from the Amargosa Wild and Scenic River and Contributing Areas, Inyo and San Bernardino Counties, California. Geospatial datasets presented are two polygon shapefiles representing the groundwater discharge areas and evapotranspiration units for the Amargosa Wild and Scenic River and contributing areas, and a raster dataset representing the vegetation index corresponding to the vegetated evapotranspiration unit.

This data release contains geospatial data for the lower Walker River basin from the 2009 publication: Allander, K.A., Smith, J.L., and Johnson, M.J., 2009, Evapotranspiration from the lower Walker River basin, west-central Nevada, water years 2005-07: U.S. Geological Survey Scientific Investigations Report 2009-5079, https://doi.org/10.3133/sir20095079.

This data release contains geospatial data for the lower Walker River basin from the 2009 publication: Allander, K.A., Smith, J.L., and Johnson, M.J., 2009, Evapotranspiration from the lower Walker River basin, west-central Nevada, water years 2005-07: U.S. Geological Survey Scientific Investigations Report 2009-5079, https://doi.org/10.3133/sir20095079.

This data release contains geospatial data for the lower Walker River basin from the 2009 publication: Allander, K.A., Smith, J.L., and Johnson, M.J., 2009, Evapotranspiration from the lower Walker River basin, west-central Nevada, water years 2005–07: U.S. Geological Survey Scientific Investigations Report 2009-5079, https://doi.org/10.3133/sir20095079.

This data release supports U.S. Geological Survey (USGS) Scientific Investigations Report 2023-5106, Groundwater Discharge by Evapotranspiration from the Amargosa Wild and Scenic River and Contributing Areas, Inyo and San Bernardino Counties, California. It consists of two comma-separated values (CSV) files containing data collected at two USGS atmospheric monitoring locations (USGS site identification numbers 355846116160401 and 355918116161801) beginning in January 2018 and lasting for approximately 1 year. The data include 30-minute values for cumulative normalized flux for 6 circular areas around each site and 30-minute values for unadjusted total evapotranspiration. The radii of the circular areas are 25, 50, 75, 100, 200, and 300 meters. More data from the USGS monitoring locations can be found in the USGS National Water Information System (U.S. Geological Survey, 2020): Amargosa River Shrub ET Station (USGS site identification number 355846116160401) https://waterdata.usgs.gov/monitoring-location/355846116160401 Amargosa River Wetland ET Station (USGS site identification number 355918116161801) https://waterdata.usgs.gov/monitoring-location/355918116161801 Reference Cited: U.S. Geological Survey, 2020, USGS water data for the Nation: U.S. Geological Survey database, accessed April 20, 2020, at http://doi.org/10.5066/F7P55KJN.

This data release supports U.S. Geological Survey (USGS) Scientific Investigations Report 2023-5106, Groundwater Discharge by Evapotranspiration from the Amargosa Wild and Scenic River and Contributing Areas, Inyo and San Bernardino Counties, California. It consists of two comma-separated values (CSV) files containing data collected at two USGS atmospheric monitoring locations (USGS site identification numbers 355846116160401 and 355918116161801) beginning in January 2018 and lasting for approximately 1 year. The data include 30-minute values for cumulative normalized flux for 6 circular areas around each site and 30-minute values for unadjusted total evapotranspiration. The radii of the circular areas are 25, 50, 75, 100, 200, and 300 meters. More data from the USGS monitoring locations can be found in the USGS National Water Information System (U.S. Geological Survey, 2020): Amargosa River Shrub ET Station (USGS site identification number 355846116160401) https://waterdata.usgs.gov/monitoring-location/355846116160401 Amargosa River Wetland ET Station (USGS site identification number 355918116161801) https://waterdata.usgs.gov/monitoring-location/355918116161801 Reference Cited: U.S. Geological Survey, 2020, USGS water data for the Nation: U.S. Geological Survey database, accessed April 20, 2020, at http://doi.org/10.5066/F7P55KJN.