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Ashley M. Helton

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Areas of groundwater discharge are hydrologically and ecologically important, and yet are difficult to predict at the river network scale. Thermal infrared imagery can be used to identify areas of groundwater discharge based on an observed temperature anomaly (colder during the late summer or warmer during the late winter). The thermal images, direct temperature measurements (11 cm depth) and discharge zone (seep) location information in this data release were collected as part of a study to evaluate and improve predicted spatial patterns of groundwater discharge. The data were collected during the late summer / early fall of 2017 along selected river reaches in the Farmington River watershed (Connecticut and Massachusetts)....
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To assess the distribution, frequency, and global extent of riverine hypoxia, we compiled 118 million paired dissolved oxygen (DO) and water temperature measurements from 125,158 unique locations in rivers in 93 countries and territories across the globe. The dataset also includes site characteristics derived from StreamCat, the National Hydrography and HydroAtlas datasets and proximal land cover derived from MODIS-based IGBP land cover types compiled using Google Earth Engine (GEE).
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Groundwater flow models have the potential to predict spatial groundwater discharge dynamics within river networks, but models are often not evaluated against discharge dynamics. The objective of this study was to understand the variation in simulated discharge dynamics (discharge location, flowpath depth, and subsurface travel time) for models with common, but varying frameworks and assumptions. The University of Connecticut in collaboration with the United States Geological Survey developed a groundwater flow model (MODFLOW-NWT) for the Farmington River Watershed (1,570 km2) in the northeastern United States and systematically varied the type of typical calibration data (well head and stream elevation); calibration...
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