Publications

Perennial snow, or firn, covers 80 % of the Greenland ice sheet and has the capacity to retain surface meltwater, influencing the ice sheet mass balance and contribution to sea-level rise. Multilayer firn models are traditionally used to simulate firn processes and estimate meltwater retention. We present, intercompare and evaluate outputs from nine firn models at four sites that...

We present measurements of the density, hydraulic conductivity, and specific discharge of a widespread firn aquifer in Antarctica, within the Wilkins Ice Shelf. At the field site, the aquifer is 16.2 m thick, starting at 13.4 m from the snow surface and transitioning from water‐saturated firn to ice at 29.6 m. Hydraulic conductivity derived from slug tests show a geometric mean value of...

Power consumption coefficients (PCCs) and dedicated flowmeter records for irrigation wells in three Utah groundwater basins were analyzed to develop a method to better characterize the accuracy of annual groundwater withdrawal estimates. The PCC method has been used by the U.S. Geological Survey in Utah since 1963 as a way to estimate groundwater withdrawal. As a result, most irrigation...

Perennial water storage in firn aquifers has been observed within the lower percolation zone of the southeast Greenland ice sheet. Spatially distributed seismic and radar observations, made ~50 km upstream of the Helheim Glacier terminus, reveal spatial variations of seismic velocity within a firn aquifer. From 1.65 to 1.8 km elevation, shear‐wave velocity (Vs) is 1,290 ± 180 m/s in the

The Glen Canyon Group Aquifer (GCGA) is the sole source of public water supply for the city of Moab, Utah, a domestic and international tourist destination. Population and tourism growth are likely to target the GCGA for future water resources, but our analysis indicates that additional withdrawals would likely be sourced from groundwater storage and not be sustained by recharge. A...

The headwaters of the Snake River are in the mountains of northwestern Wyoming. Maintaining the recognized high quality of water in Grand Teton National Park is a National Park Service (NPS) priority. To characterize and understand the water resources of Grand Teton National Park, the NPS established a monitoring program to monitor the quality of area surface waters. Beginning in 2006...

Pine and Wah Wah Valleys are neighboring structural basins that encompass about 1,330 square miles in Beaver, Iron, and Millard Counties in Utah, approximately 50 miles northwest of Cedar City, Utah, and 50 miles southeast of Baker, Nevada. Perennial streamflow is limited and only exists in higher-altitude reaches of small mountain streams in both basins. Groundwater is in unconsolidated...

In the arid landscape south of the Grand Canyon, natural springs and seeps are a critical resource for endemic species and Native American tribes. Groundwater is potentially threatened by expanding populations, visitations, and mineral extraction activities. Environmental tracers including noble gases, stable isotopes of hydrogen and oxygen in water, tritium, and carbon-14 were used to

Springs and groundwater seeps along the South Rim of the Grand Canyon serve an important function for the region’s ecosystems, residents (both human and wild animal), and economy. However, these springs and seeps are potentially vulnerable to contamination, increased groundwater extraction, or reduced recharge due to climate change. Protection of South Rim groundwater resources requires...

Groundwater makes up a primary portion of the water supply in many parts of Utah, with annual withdrawals estimated at more than 1,000,000 acre-feet per year. Increases to groundwater withdrawal and land use may negatively impact water availability. Ensuring availability of clean water requires understanding how water quality has changed over time and how natural and human activities and...

Groundwater resources in the Spanish Valley watershed in southern Utah were quantified for the first time since the early 1970s. The primary objectives of this study were (1) to better understand sources of recharge to, groundwater flow directions within, and discharge points for both the valley-fill and Glen Canyon Group aquifers (VFA and GCGA), and (2) to quantify groundwater budget...

Understanding the drivers and timescales over which groundwater quality changes informs groundwater management, use, and protection. To better understand timescales of water-quality change over short (daily to monthly) and long (seasonal to decadal) timescales, the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Enhanced Trends Network (ETN) program instrumented and...