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Enhancement of a parsimonious water balance model to simulate surface hydrology in a glacierized watershed

The U.S. Geological Survey monthly water balance model (MWBM) was enhanced with the capability to simulate glaciers in order to make it more suitable for simulating cold region hydrology. The new model, MWBMglacier, is demonstrated in the heavily glacierized and ecologically important Copper River watershed in Southcentral Alaska. Simulated water budget components compared well to satellite‐based
Melissa M. Valentin, Roland J. Viger, Ashley E. Van Beusekom, Lauren E. Hay, Terri S. Hogue, Nathan Leon Foks

Common hydraulic fracturing fluid additives alter the structure and function of anaerobic microbial communities

The development of unconventional oil and gas (UOG) resources results in the production of large volumes of wastewater containing a complex mixture of hydraulic fracturing chemical additives and components from the formation. The release of these wastewaters into the environment poses potential risks that are poorly understood. Microbial communities in stream sediments form the base of the food ch
Adam C. Mumford, Denise M. Akob, J. Grace Klinges, Isabelle M. Cozzarelli

Demography of the Pacific walrus (Odobenus rosmarus divergens) in a changing Arctic

The Pacific walrus (Odobenus rosmarus divergens) is a candidate to be listed as an endangered species under United States law, in part, because of climate change‐related concerns. While the population was known to be declining in the 1980s and 1990s, its recent status has not been determined. We developed Bayesian models of walrus population dynamics to assess the population by synthesizing inform
Rebecca L. Taylor, Mark S. Udevitz, Chadwick V. Jay, John J. Citta, Lori T. Quakenbush, Patrick R. Lemons, Jonathan A. Snyder

Mapping burned areas using dense time-series of Landsat data

Complete and accurate burned area data are needed to document patterns of fires, to quantify relationships between the patterns and drivers of fire occurrence, and to assess the impacts of fires on human and natural systems. Unfortunately, in many areas existing fire occurrence datasets are known to be incomplete. Consequently, the need to systematically collect burned area information has been re
Todd Hawbaker, Melanie K. Vanderhoof, Yen-Ju G. Beal, Joshua Takacs, Gail L. Schmidt, Jeff T. Falgout, Brad Williams, Nicole M. Brunner, Megan K. Caldwell, Joshua J. Picotte, Stephen M. Howard, Susan Stitt, John L. Dwyer

Benchmarking computational fluid dynamics models of lava flow simulation for hazard assessment, forecasting, and risk management

Numerical simulations of lava flow emplacement are valuable for assessing lava flow hazards, forecasting active flows, designing flow mitigation measures, interpreting past eruptions, and understanding the controls on lava flow behavior. Existing lava flow models vary in simplifying assumptions, physics, dimensionality, and the degree to which they have been validated against analytical solutions,
Hannah R. Dietterich, Einat Lev, Jiangzhi Chen, Jacob A. Richardson, Katharine V. Cashman

Using tri-axial accelerometers to identify wild polar bear behaviors

Tri-axial accelerometers have been used to remotely identify the behaviors of a wide range of taxa. Assigning behaviors to accelerometer data often involves the use of captive animals or surrogate species, as their accelerometer signatures are generally assumed to be similar to those of their wild counterparts. However, this has rarely been tested. Validated accelerometer data are needed for polar
Anthony M. Pagano, Karyn D. Rode, A. Cutting, M.A. Owen, S. Jensen, J.V. Ware, C.T. Robbins, George M. Durner, Todd C. Atwood, M.E. Obbard, K.R. Middel, G.W. Thiemann, T.M. Williams

Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (
Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza

Inner-shelf ocean dynamics and seafloor morphologic changes during Hurricane Sandy

Hurricane Sandy was one of the most destructive hurricanes in US history, making landfall on the New Jersey coast on Oct 30, 2012. Storm impacts included several barrier island breaches, massive coastal erosion, and flooding. While changes to the subaerial landscape are relatively easily observed, storm-induced changes to the adjacent shoreface and inner continental shelf are more difficult to eva
John C. Warner, William C. Schwab, Jeffrey H. List, Ilgar Safak, Maria Liste, Wayne E. Baldwin

Parameter regionalization of a monthly water balance model for the conterminous United States

A parameter regionalization scheme to transfer parameter values from gaged to ungaged areas for a monthly water balance model (MWBM) was developed and tested for the conterminous United States (CONUS). The Fourier Amplitude Sensitivity Test, a global-sensitivity algorithm, was implemented on a MWBM to generate parameter sensitivities on a set of 109 951 hydrologic response units (HRUs) across the
Andrew R. Bock, Lauren E. Hay, Gregory J. McCabe, Steven L. Markstrom, R. Dwight Atkinson

Making it and breaking it in the Midwest: Continental assembly and rifting from modeling of EarthScope magnetotelluric data

A three-dimensional lithospheric-scale resistivity model of the North American mid-continent has been estimated based upon EarthScope magnetotelluric data. Details of the resistivity model are discussed in relation to lithospheric sutures, defined primarily from aeromagnetic and geochronologic data, which record the southward growth of the Laurentian margin in the Proterozoic. The resistivity sign
Paul A. Bedrosian

Mapping the 3-D extent of the Northern Lobe of the Bushveld layered mafic intrusion from geophysical data

Geophysical models image the 3D geometry of the mafic portion of the Bushveld Complex north of the Thabazimbi-Murchison Lineament (TML), critical for understanding the origin of the world's largest layered mafic intrusion and platinum group element deposits. The combination of the gravity and magnetic data with recent seismic, MT, borehole and rock property measurements powerfully constrains the m
Carol A. Finn, Paul A. Bedrosian, Janine Cole, Tshepo David Khoza, Susan J. Webb

Robust estimates of environmental effects on population vital rates: an integrated capture–recapture model of seasonal brook trout growth, survival and movement in a stream network

Modelling the effects of environmental change on populations is a key challenge for ecologists, particularly as the pace of change increases. Currently, modelling efforts are limited by difficulties in establishing robust relationships between environmental drivers and population responses.We developed an integrated capture–recapture state-space model to estimate the effects of two key environment
Benjamin H. Letcher, Paul Schueller, Ronald D. Bassar, Keith H. Nislow, Jason A. Coombs, Krzysztof Sakrejda, Michael Morrissey, Douglas B. Sigourney, Andrew R. Whiteley, Matthew J. O'Donnell, Todd L. Dubreuil