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An interactive viewer to improve operational aftershock forecasts

The U.S. Geological Survey (USGS) issues forecasts for aftershocks about 20 minutes after most earthquakes above M 5 in the United States and its territories, and updates these forecasts 75 times during the first year. Most of the forecasts are issued automatically, but some forecasts require manual intervention to maintain accuracy. It is important to identify the sequences whose forecasts will b
Authors
Gabrielle Madison Paris, Andrew J. Michael

Habitat associations of riverine fishes among rocky shoals

Understanding species' associations with physical habitat conditions is a fundamental goal of ecology. For organisms that occupy lotic ecosystems, relationships to streamflow are of particular importance, but these associations are unstudied for most species. We tested the predictability of fish–microhabitat relationships in river shoals (shallow, rocky areas with relatively swift water flow) usin
Authors
Anna Y. Baynes, Mary Freeman, S. Kyle McKay, Seth J. Wenger

Towards real-time probabilistic ash deposition forecasting for New Zealand

Volcanic ashfall forecasts are highly dependent on eruption source parameters (ESPs) and synoptic weather conditions at the time and location of the eruption. In New Zealand, MetService and GNS Science have been jointly developing an ashfall forecast system that incorporates four-dimensional high-resolution numerical weather prediction (NWP) and ESPs into the HYSPLIT model, a state-of-the art hybr
Authors
Rosa Transcoso, Yannik Behr, Tony Hurst, Natalia Irma Deligne

Evidence of active Quaternary deformation on the Great Valley fault system near Winters, northern California

The Great Valley fault system defines the tectonic boundary between the Coast Ranges and the Central Valley in California, is active throughout the Quaternary, and has been the source of several significant (M > 6) historic earthquakes, including the 1983 M 6.5 Coalinga earthquake and the 1892 Vacaville–Winters earthquake sequence. However, the locations and geometries of individual faults in the
Authors
Charles Cashman Trexler, Alexander E. Morelan, Rufus D. Catchings, Mark Goldman, Jack Willard

High resolution spatiotemporal patterns of flow at the landscape scale in montane non-perennial streams

Intermittent and ephemeral streams in dryland environments support diverse assemblages of aquatic and terrestrial life. Understanding when and where water flows provide insights into the availability of water, its response to external controlling factors, and potential sensitivity to climate change and a host of human activities. Knowledge regarding the timing of drying/wetting cycles can also be
Authors
Romy Sabathier, Michael Bliss Singer, John C Stella, Dar A. Roberts, Kelly K. Caylor, Kristin Jaeger, Julian Olden

Seismic evidence for magmatic underplating along the Kodiak-Bowie Seamount Chain, Gulf of Alaska

Oceanic crust formed at mid-ocean ridges may be later modified by off-ridge magmatism forming seamounts, guyots, and islands. We investigate processes associated with seamount formation in the Gulf of Alaska Seamount Province using two coincident seismic reflection/wide-angle profiles. A north-south profile crosses the Kodiak-Bowie Seamount Chain and Aja fracture zone (FZ), and an orthogonal east-
Authors
Gail L. Christeson, Sean P.S. Gulick, Maureen A. L. Walton, Ginger Barth

Estrogenic activity response to best management practice implementation in agricultural watersheds in the Chesapeake Bay watershed

Best management practices (BMPs) have been predominantly used throughout the Chesapeake Bay watershed (CBW) to reduce nutrients and sediments entering streams, rivers, and the bay. These practices have been successful in reducing loads entering the estuary and have shown the potential to reduce other contaminants (pesticides, hormonally active compounds, pathogens) in localized studies and modeled
Authors
Stephanie Gordon, Tyler Wagner, Kelly L. Smalling, Olivia H. Devereux

GCPs free photogrammetry for estimating tree height and crown diameter in Arizona cypress plantation using UAV-Mounted GNSS RTK

One of the main challenges of using unmanned aerial vehicles (UAVs) in forest data acquisition is the implementation of Ground Control Points (GCPs) as a mandatory step, which is sometimes impossible for inaccessible areas or within canopy closures. This study aimed to test the accuracy of a UAV-mounted GNSS RTK (real-time kinematic) system for calculating tree height and crown height without any
Authors
Morteza Pourreza, Fardin Moradi, Mohammad Khosravi, Azade Deljouei, Melanie K. Vanderhoof

Individual characteristics and abiotic factors influence out-migration dynamics of juvenile bull trout

Fragmentation of rivers through anthropogenic modifications poses an imminent threat to the persistence of migratory fish, necessitating direct actions such as trap-and-haul programs to restore and conserve the migratory life-history component in populations of partially migratory species such as bull trout Salvelinus confluentus. We used a PIT-tag system to assess how biological and abiotic facto
Authors
Madeline C. Lewis, Christopher S. Guy, Eric W. Oldenburg, Thomas E. McMahon

Combination of acoustic telemetry and side-scan sonar advances suppression efforts for invasive lake trout in a submontane lake

Expansion of an invasive Lake Trout Salvelinus namaycush population in Swan Lake, Montana, threatens a core area population of Bull Trout S. confluentus. Given the recent development of novel suppression methods, such as use of carcass analog pellets to cause high mortality of embryos, there was a need to quantify spawning season aggregation sites, site use, and spawning habitat for Lake Trout in
Authors
Michael J. Siemiantkowski, Christopher S. Guy, Todd M. Koel, Lusha M. Tronstad, Carter R. Fredenberg, Leo R. Rosenthal

Geochemical evidence for diachronous uplift and synchronous collapse of the high elevation Variscan hinterland

Competing end-member models for the late Paleozoic Variscan orogeny (ca. 360-290 Ma) alternatively suggest moderate 2-3 km elevations underlain by relatively thin crust (55 km) that supported high 4-5 km elevations. We tested these models and quantified the crustal thickness and elevation evolution of the Variscan orogeny using igneous trace element geochemical proxies. The data suggest that thick
Authors
Ian William Hillenbrand, Michael L. Williams

Apophis specific action team report

This report about Asteroid (99942) Apophis's Earth close approach on April 13, 2029 was generated by a Specific Action Team (SAT) formed by the Small Body Assessment Group (SBAG) at the request of NASAs Planetary Science Division (PSD). The SAT assessed the current predictions for the effects that may occur due to the close encounter, evaluated observing capabilities, and identified possible inves
Authors
J. L. Dotson, M. Brozovic, S. Chesley, S. Jarmak, N. Moskovitz, A. Rivkin, P. Sanchez, D. Souami, Timothy N. Titus