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Groundwater-level conditions, generalized groundwater potentiometric surfaces, and generalized flow directions at the decommissioned Naval Air Warfare Center in West Trenton, New Jersey, were evaluated for calendar year 2018. Groundwater levels measured continuously in five on-site wells and one nearby off-site well were plotted as hydrographs for January 1, 2018, through...

The hydrogeology below large surface water features such as rivers and estuaries is universally under-informed at the long reach to basin scales (tens of km+). This challenge inhibits the accurate modeling of fresh/saline groundwater interfaces and groundwater/surface water exchange patterns at management-relevant spatial extents. Here we introduce a towed, floating...

Invertebrates are well-known predators of amphibians with many documented cases of spiders preying upon anurans (reviewed in Toledo 2005. Herpetol. Rev. 36:395–400). Wolf spiders are known to feed on a variety of frogs, including those in the genus Acris (Blackburn et al. 2002. Herpetol. Rev. 33:299). Although typically terrestrial, wolf...

Snake fungal disease (SFD), or ophidiomycosis, is caused by the fungus Ophidiomyces ophiodiicola (Allender et al. 2015; Lorch et al. 2015). SFD is widespread across wild populations in the eastern United States (Lorch et al. 2016) and is known to infect more than 30 species of snake in North America...

The ShakeAlert earthquake early warning system aims to alert people who experience modified Mercalli intensity (MMI) IV+ shaking during an earthquake using source estimates (magnitude and location) to estimate median‐expected peak ground motions with distance, then using these ground motions to determine median‐expected MMI and thus the extent of MMI...

Seasonal streamflow forecast bias, changes in climate, snowpack, and land cover, and the effects of these changes on relations between basin‐wide snowpack, SNOw TELemetry (SNOTEL) station snowpack, and seasonal streamflow were evaluated in the headwaters of the Rio Grande, Colorado. Results indicate that shifts in the seasonality of precipitation and...

Rainfall intensity‐duration (ID) thresholds are commonly used to assess the potential for runoff‐generated debris flows, but the sensitivity of these thresholds to sediment supply, which can change rapidly with time, is relatively unexplored. Furthermore, debris flows often self‐organize into distinct surges, but the factors controlling the magnitude and frequency of...

Melt and gas transfer processes are essential to the formation and growth of the Earth’s crust and for sustaining volcanic activity. These processes also play a major role in magma fractionation at shallow depths (<10 km) where magmas stall rheologically and solidify. In this scenario, the conditions of melt and...

We use a large instrumental dataset from the 2019 Ridgecrest earthquake sequence (Rekoske et al., 2019, 2020) to examine repeatable source‐, path‐, and site‐specific ground motions. A mixed‐effects analysis is used to partition total residuals relative to the Boore et al. (2014;...

Comparison of investigations of the 1979 and 2017 cored boreholes coupled with continued observations of the dynamic surface of Surtsey has modified our concepts of the subsurface structure of the volcano. A geometrical analysis of the 2017 vertical and inclined cores indicates that near-surface layering dips westerly, indicating that the...

The authors regret that two thirds of the San Francisco Bay biomass data included in the Landsat random forest models were not scaled to the proper units of grams per square meter. This error affects the Landsat-only models in the article, which are models #1-4 shown in Table 6. The...

Recent detections of avian malarial parasites in native and non-native forest birds at Hakalau Forest National Wildlife Refuge and reports of epidemic transmission of the disease in high elevation habitats as well as controversy over accuracy of the PCR (polymerase chain reaction) diagnostic test that was being used led to...

Sabancaya is the most active volcano of the Ampato-Sabancaya Volcanic Complex (ASVC) in southern Perú and has been erupting since 2016. The analysis of ascending and descending Sentinel-1 orbits (DInSAR) and Global Navigation Satellite System (GNSS) datasets from 2014 to 2019 imaged a radially symmetric inflating area,...

Executive SummaryNative steelhead (anadromous form of rainbow trout [Oncorhynchus mykiss]) and bridgelip sucker (Catostomus columbianus) were historically used by the Kah-miltpah (Rock Creek) Band for sustenance, trade, and traditional practices in Rock Creek, a tributary to the Columbia River in southeastern Washington State. Rock Creek flows south to the Columbia...

Spatial synchrony—correlated abundance fluctuations among distinct populations—is associated with increased extinction risk but is not a component of widely-used extinction risk assessments (e.g., IUCN Red List, U.S. Fish and Wildlife Service’s Species Status Assessment). Alongside traditional viability metrics (i.e., the number of populations, their spatial extent, the status of each...

Nowcasts are tools used to provide timely and accurate water-quality assessments of threats to drinking-water and recreational resources from fecal contamination or cyanobacterial harmful algal blooms. They use mathematical models and techniques to provide near-real-time estimates of fecal-indicator bacteria (FIB) and cyanotoxin concentrations. Techniques include logic-based thresholds, decision trees (built...

The role of subduction zone geometry in the nucleation and propagation of great-sized earthquake ruptures is an important topic for earthquake hazard, since knowing how big an earthquake can be on a given fault is fundamentally important. Past studies have shown subducting bathymetric features (e.g. ridges, fracture zones, seamount...

American bullfrogs (Lithobates catesbeianus) are significant invaders in many places and can negatively impact native species. Despite their impact and wide distribution, little is known about their demography. We used five years of capture mark-recapture data to estimate annual apparent survival of post-metamorphic bullfrogs in a population on the Buenos...

On-orbit calibration requirements for a space-based climate observing system include long-term sensor response stability and reliable inter-calibration of multiple sensors, both contemporaneous and in succession. The difficulties with achieving these for reflected solar wavelength instruments are well known. The Moon can be considered a diffuse reflector of sunlight, and its...

Yosemite National Park, located in the central part of California’s Sierra Nevada mountains, is a glacially carved landscape filled with iconic rock formations such as Cathedral Peak, El Capitan, and Half Dome. Igneous rocks, consisting primarily of variations of granite, granodiorite, and tonalite, make up the majority of the bedrock...

On the basis of lifetime cancer risks, lead-210 (210Pb) and polonium-210 (210Po) ≥ 1.0 and 0.7 pCi/L (picocuries per liter), respectively, in drinking-water supplies may pose human-health concerns. 210Pb and 210Po were detected at concentrations greater than these thresholds at 3.7 and 1.5%,...

Recreational fisheries have high economic worth, valued at US$190 billion globally. An important, but underappreciated, secondary value of recreational catch is its role as a source of food. This contribution is poorly understood due to difficulty in estimating recreational harvest at spatial scales beyond a single...

Gas hydrate is an ice-like form of water and low molecular weight gas stable at temperatures of roughly -10ºC to 25ºC and pressures of ~3 to 30 MPa in geologic systems. Natural gas hydrates sequester an estimated one-sixth of Earth’s methane and are found primarily in deepwater marine sediments on...

Prior to emergence as fry, salmonid embryos incubating within gravel nests called “redds” are vulnerable to substrate mobilization and lowering of the streambed, a process termed “streambed scour,” during floods. Water managers regulating discharge in salmonid-bearing rivers need information about the magnitude of discharge during which the scour of substrate...

PremiseDelimiting biodiversity units is difficult in organisms in which differentiation is obscured by hybridization, plasticity, and other factors that blur phenotypic boundaries. Such work is more complicated when the focal units are subspecies, the definition of which has not been broadly explored in the era of modern...