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User guide to the FireCLIME Vulnerability Assessment (VA) Tool: A rapid and flexible system for assessing ecosystem vulnerability to climate-fire interactions
Megan Friggens, Rachel A. Loehman, Andi Thode, William T. Flatley, Alexander Evans, Windy Bunn, Craig Wilcox, Stephanie Mueller, Larissa Yocum, Donald A. Falk
2019, Report
Decisionmakers need better methods for identifying critical ecosystem vulnerabilities to changing climate and fire regimes. Climate-wildfire-vegetation interactions are complex and hinder classification and projection necessary for development of management strategies. One such vulnerability assessment (VA) is FireCLIME VA, which allows users to compare management strategies under various climate scenarios and...
Improvements in seismic resolution and current limitations in the Global Seismographic Network
Adam T. Ringler, J. Steim, David C. Wilson, R. Widmer-Schnidrig, Robert Anthony
2019, Geophysical Journal International (220) 508-521
Station noise levels play a fundamental limitation in our ability to detect seismic signals. These noise levels are frequency-dependent and arise from a number of physically different drivers. At periods greater than 100 s, station noise levels are often limited by the self-noise of the instrument as well...
Hysteretic response of solutes and turbidity at the event scale across forested tropical montane watersheds
Adam S. Wymore, Miguel C. Leon, James B. Shanley, William C. McDowell
2019, Frontiers in Earth Science (7)
Concentration-discharge relationships are a key tool for understanding the sourcing and transport of material from watersheds to fluvial networks. Storm events in particular provide insight into variability in the sources of solutes and sediment within watersheds, and the hydrologic pathways that connect hillslope to stream channel. Here we examine high-frequency...
Identifying credible and diverse GCMs for regional climate change studies—case study: Northeastern United States
Ambarish V. Karmalkar, Jeanne M. Thibeault, Alexander Bryan, Anji Seth
2019, Climatic Change (154) 367-386
Climate data obtained from global climate models (GCMs) form the basis of most studies of regional climate change and its impacts. Using the northeastern US as a test case, we develop a framework to systematically sub-select reliable models for use in climate change studies in the region. We retain 14...
Debris-flow monitoring and warning: Review and examples
Marcel Hurlimann, Velio Coviello, Coraline Bel, Xiaojun Guo, Matteo Berti, Christoph Graf, Johannes Hubl, Shusuke Miyata, Joel B. Smith, Hsiao-Yuan Yin
2019, Earth-Science Reviews (199)
Debris flows represent one of the most dangerous types of mass movements, because of their high velocities, large impact forces and long runout distances. This review describes the available debris-flow monitoring techniques and proposes recommendations to inform the design of future monitoring and warning/alarm systems. The selection and application of...
Total grain size distribution of an intense Hawaiian fountaining event: Case study of the1959 Kīlauea Iki eruption
Sebastian B Mueller, Bruce F. Houghton, Donald A. Swanson, Matthieu Poret, Sarah A. Fagents
2019, Bulletin of Volcanology (81)
The 1959 eruption of Kīlauea Iki on the Island of Hawai’i is a principal example of powerful Hawaiian fountaining. Over 36 days (including repose periods), 16 fountaining episodes created a small cone, a downwind tephra blanket of approximately 0.003 km3 and a lava lake of about 0.04 km3 volume. During the explosive activity, the maximum...
Comparing and improving methods for reconstructing peatland water-table depth from testate amoebae
Connor Nolan, John Tipton, Robert K. Booth, Mevin Hooten, Stephen Jackson
2019, Holocene (29) 1350-1361
Proxies that use changes in the composition of ecological communities to reconstruct temporal changes in an environmental covariate are commonly used in paleoclimatology and paleolimnology. Existing methods, such as weighted averaging and modern analog technique, relate compositional data to the covariate in very simple ways, and different methods are seldom compared...
A Generalized Additive Model approach to evaluating water quality: Chesapeake Bay Case Study
Rebecca Murphy, Elgin Perry, Jon Harcum, Jennifer L. Keisman
2019, Environmental Modelling & Software (118)
Nutrient-reduction efforts have been undertaken in recent decades to mitigate the impacts of eutrophication in coastal and estuarine systems worldwide. To track progress in response to one of these efforts we use Generalized Additive Models (GAMs) to evaluate a diverse suite of water quality constituents over a 32-year period in...
Dextral, normal, and sinistral faulting across the eastern California shear zone-Mina deflection transition, California-Nevada
Kevin DeLano, Jeffrey Lee, Rachelle Roper, Andrew T. Calvert
2019, Geosphere (15) 1206-1239
Strike-slip faults commonly include extensional and contractional bends and stepovers, whereas rotational stepovers are less common. The Volcanic Tableland, Black Mountain, and River Spring areas (California and Nevada, USA) (hereafter referred to as the VBR region) straddle the transition from the dominantly NW-striking dextral faults that define the northwestern part...
Relevance of wind stress and wave-dependent ocean surface roughness on the generation of winter meteotsunamis in Northern Gulf of Mexico
Lijing Shi, Maitane Olabarrieta, Arnoldo Valle-Levinson, John C. Warner
2019, Ocean Modeling (140)
Meteotsunamis associated with passing squall lines are often observed ahead of cold fronts during winter seasons in Northern Gulf of Mexico. These types of meteotsunamis occur simultaneously with wind speed variations (~5-20 m/s) and sea-level atmospheric pressure oscillations (~1-6 hPa) with periods between 2 hours to several minutes. In order...
Intense hurricane activity over the past 1500 years at South Andros Island, The Bahamas
Elizabeth Wallace, Jeffrey P. Donnelly, Peter J. van Hengstum, Charlotte Winman, Richard Sullivan, Tyler Winkler, Nicole D'Entremont, Michael Toomey, Nancy A. Albury
2019, Paleoceanography and Paleoclimatology (34) 1761-1783
Hurricanes cause substantial loss of life and resources in coastal areas. Unfortunately, historical hurricane records are too short and incomplete to capture hurricane-climate interactions on multi-decadal and longer timescales. Coarse-grained, hurricane-induced deposits preserved in blue holes in the Caribbean can provide records of past hurricane activity extending back thousands of...
Morphological identification of Bighead Carp, Silver Carp, and Grass Carp eggs using random forests machine learning classification
Carlos A. Camacho, Christopher J. Sullivan, Michael J. Weber, Clay Pierce
2019, North American Journal of Fisheries Management (39) 1373-1384
Visual identification of fish eggs is difficult and unreliable due to a lack of information on the morphological egg characteristics of many species. We used random forests machine learning to predict the identity of genetically identified Bighead Carp Hypophthalmichthys nobilis, Grass Carp Ctenopharyngodon idella, and Silver Carp H. molitrix eggs based on egg morphometric and...
Characterizing range-wide population divergence in an alpine-endemic bird: A comparison of genetic and genomic approaches
Kathryn Langin, Cameron L. Aldridge, Jennifer A. Fike, Robert S. Cornman, Kathy M Martin, Greg T Wann, Amy E. Seglund, Michael A Schroeder, David P Benson, Brad C. Fedy, Jessica R. Young, Scott D. Wilson, Don H Wolfe, Clait E. Braun, Sara J. Oyler-McCance
2019, Conservation Genetics (19) 1471-1485
The delineation of intraspecific units that are evolutionarily and demographically distinct is an important step in the development of species-specific management plans. Neutral genetic variation has served as the primary data source for delineating “evolutionarily significant units,” but with recent advances in genomic technology, we now have an unprecedented ability...
Climate-driven state shifts in the Prairie Pothole Region: Assessing future impacts relevant to the management of wetland habitats critical to waterfowl
David M. Mushet, Owen P. McKenna
2019, Report
Embedded within the North American Prairie Pothole Region (PPR) are millions of small, depressional wetlands that annually support 50–80% of the continent’s waterfowl production. We recently assembled evidence that demonstrates a change towards a wetter climate that is driving a shift in the state of the region’s wetland ecosystems. This...
Controls on eolian landscape evolution in fractured bedrock
Jonathan P. Perkins, Noah J. Finnegan, Shanaka L. de Silva, Michael J. Willis
2019, Geophysical Research Letters (46) 12012-12020
Wind abrasion is important for planetary landscape evolution, and wind‐abraded bedrock landscapes contain many landforms that are difficult to interpret. Here we exploit a natural experiment in Chile where topographic shielding by an upwind lava flow yields diverse erosional landforms in a downwind ignimbrite. Using a 3‐D topographic wind model,...
Variability in results from mineralogical and organic geochemical interlaboratory testing of U. S. Geological Survey shale reference materials
Justin E. Birdwell, Stephen A. Wilson
2019, Conference Paper, Proceedings of the 7th Unconventional Resources Technology Conference
The expansion of unconventional petroleum resource exploration and production in the United States has led to an increase in source rock characterization efforts, particularly related to bulk organic and mineralogical properties. To support the analytical and research needs of industry and academia, as well as internal work, the U.S. Geological...
Evolutionary history predicts high-impact invasions by herbivorous insects
Angela M. Mech, Kathryn A. Thomas, Travis D. Marsico, Daniel A. Herms, Craig Allen, Matthew P. Ayres, Kamal J.K. Gandhi, Jessica Gurevitch, Nathan P. Havill, Ruth A. Hufbauer, Andrew M. Liebhold, Kenneth F. Raffa, Ashley N. Schulz, Daniel R. Uden, Patrick C. Tobin
2019, Ecology and Evolution (9) 12216-12230
A long‐standing goal of invasion biology is to identify factors driving highly variable impacts of non‐native species. Although hypotheses exist that emphasize the role of evolutionary history (e.g., enemy release hypothesis & defense‐free space hypothesis), predicting the impact of non‐native herbivorous insects has eluded scientists for over a century. Using a...
Competitive interactions among H, CU, and Zn ion moderate aqueous uptake of Cu and Zn by an aquatic insect
Daniel J. Cain, Marie Noele Croteau, Christopher C. Fuller
2019, Environmental Pollution (255)
The absorption of aqueous copper (Cu) and zinc (Zn) by aquatic insects, a group widely used to assess water quality, is unresolved. This study examined interactions among Cu, Zn, and protons that potentially moderate Cu and Zn uptake by the acid-tolerant stonefly Zapada sp. Saturation uptake kinetics was imposed to...
Mechanics of inflationary deformation during Caldera collapse: Evidence from the 2018 Kīlauea Eruption
Paul Segall, Kyle R. Anderson, Ingrid A. Johanson, Asta Miklius
2019, Geophysical Research Letters (46) 11782-11789
During the 2018 Kilauea eruption the caldera ffloor dropped 500 meters in 62 nearly periodic events of up to 8 meters. Caldera collapse maintains pressure in the magma reservoir necessary to sustain high-rate eruptions. The 2018 collapses were accompanied by inflationary tilts and displacements, similar to observations at other basaltic...
Evaluating the effects of barriers on Slimy Sculpin movement and population connectivity using novel sibship-based and traditional genetic metrics
Spencer Y. Weinstein, Jason A. Coombs, Keith H. Nislow, Chris Riley, Allison H. Roy, Andrew R. Whiteley
2019, Transactions of the American Fisheries Society (148) 1117-1131
Population genetics-based approaches can provide robust and cost-effective ways to assess the effects of potential barriers, including dams and road-stream crossings, on the passage and population connectivity of aquatic organisms. Determining the best way to apply and modify genetic tools for different species and situations is essential for making these...
Projected urban growth in the Southeastern USA puts small streams at risk
Peter C. Van Metre, Ian R. Waite, Sharon L. Qi, Barbara Mahler, Adam Terando, Michael Wieczorek, Michael R. Meador, Paul M. Bradley, Celeste A. Journey, Travis S. Schmidt, Daren M. Carlisle
2019, PLoS ONE (10)
Future land-use development has the potential to profoundly affect the health of aquatic ecosystems in the coming decades. We developed regression models predicting the loss of sensitive fish (R2=0.39) and macroinvertebrate (R2=0.64) taxa as a function of urban and agricultural land uses and applied them to projected urbanization of...
The effect of brine on the electrical properties of methane hydrate
Ryan Lu, Laura A. Stern, Wyatt L. Du Frane, John C. Pinkston, J. Murray Roberts, S. Constable
2019, Journal of Geophysical Research (124) 10877-10892
Gas hydrates possess lower electrical conductivity (inverse of resistivity) than either seawater or ice, but higher than clastic silts and sands, such that electromagnetic methods can be employed to help identify their natural formation in marine and permafrost environments. Controlled laboratory studies offer a means to...
Detrital zircon geochronology along a structural transect across the Kahiltna assemblage in the western Alaska Range: Implications for emplacement of the Alexander-Wrangellia-Peninsular terrane against North America
Stephen E. Box, Susan M. Karl, James V. Jones III, Dwight Bradley, Peter J. Haeussler, Paul B. O’Sullivan
2019, Geosphere (15) 1774-1808
The Kahiltna assemblage in the western Alaska Range consists of deformed Upper Jurassic and Cretaceous clastic strata that lie between the Alexander-Wrangellia-Peninsular (AWP) terrane to the south, and the Farewell and other peri-cratonic terranes to the north. Differences in detrital zircon populations and sandstone petrography allow geographic separation of the...
A mechanistic understanding of ecological responses to land-use change in headwater streams
Richard H. Walker, Annika W. Walters
2019, Ecosphere (10)
Anthropogenic activities, such as oil and natural gas development (ONGD), have significantly altered the landscape. It is often challenging to identify the mechanistic processes underlying ecological responses to land-use change (LUC). In aquatic ecosystems, alterations to habitat and food availability and water quality associated with increased...
Spatial and temporal distribution of bacterial indicators and microbial-source tracking within Tumacácori National Historical Park and the upper Santa Cruz River, southern Arizona and northern Mexico, 2015–2016
Nicholas V. Paretti, Christopher M. Kephart, Thomas J. Porter, Edyth Hermosillo, Jay R. Cederberg, Justine P. Mayo, Bruce Gungle, Alissa L. Coes, Rachel S. Tucci, Laura M. Norman
2019, Scientific Investigations Report 2019-5108
Tumacácori National Historical Park (TUMA) in southern Arizona protects the culturally important Mission San José de Tumacácori, while also managing a part of the ecologically diverse riparian corridor of the Santa Cruz River. The quality of the water flowing through depends solely on upstream watershed activities, and among the water-quality...