Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases
Peter H. Barry, Justin T. Kulongoski, Matthew K. Landon, R. L. Tyne, Janice M. Gillespie, Michael J. Stephens, D.J. Hillegonds, D.J. Byrne, C.J. Ballentine
2018, Earth and Planetary Science Letters (496) 57-67
Enhanced oil recovery (EOR) and hydraulic fracturing practices are commonly used methods to improve hydrocarbon extraction efficiency; however the environmental impacts of such practices remain poorly understood. EOR is particularly prevalent in oil fields throughout California where water resources are in high demand and disposal of high volumes of produced...
Experimental evidence of long-term reproductive costs in a colonial nesting seabird
Aly McKnight, Erik J. Blomberg, Gregory H. Golet, David B. Irons, Cyndy Loftin, Shawn T. McKinney
2018, Journal of Avian Biology (49)
Trade-offs between current and future reproduction are central to the evolution of life histories. Experiments that manipulate brood size provide an effective approach to investigating future costs of current reproduction. Most manipulative studies to date, however, have addressed only the short-term effects of brood size manipulation. Our goal was to...
High latitude Southern Hemisphere fire history during the mid-late Holocene (750- 6000 yr BP)
Dario Battistel, Natalie M. Kehrwald, Piero Zennaro, Giuseppe Pellegrino, Elena Barbaro, Roberta Zangrando, Xanthi X. Pedeli, Cristiano Varin, Andrea Spolaor, Paul T. Vallelonga, Andrea Gambaro, Carlo Barbante
2018, Climate of the Past (14) 871-886
We determined the specific biomass burning biomarker levoglucosan in an ice core from the TALos Dome Ice CorE drilling project (TALDICE) during the mid- to late Holocene (6000–750 BP). The levoglucosan record is characterized by a long-term increase with higher rates starting at ∼ 4000 BP and peaks between 2500 and 1500 BP. The...
Regional spectral analysis of moderate earthquakes in northeastern North America—Final Report to the Nuclear Regulatory Commission, Project V6240, Task 3
Jack Boatwright
2018, Open-File Report 2018-1073
We analyze the Fourier spectra of S+Lg+surface wave groups from the horizontal and vertical components of broadband and accelerogram recordings of 120 small and moderate (2< Mw <6) earthquakes recorded by Canadian and American stations sited on rock at distances from 3 to 600 kilometers. There are seven Mw 4.0–4.5,...
Shoreline erosion at selected areas along Lake Sharpe on the Lower Brule Reservation in South Dakota, 1966–2015
Ryan F. Thompson, John F. Stamm
2018, Scientific Investigations Report 2018-5058
The Lower Brule Reservation in central South Dakota is losing land because of shoreline erosion along Lake Sharpe, a reservoir on the Missouri River, which has caused detrimental effects for the Lower Brule Sioux Tribe including losses of cultural sites, recreation access points, wildlife habitat, irrigated cropland, and landmass. To...
A model ensemble for projecting multi‐decadal coastal cliff retreat during the 21st century
Patrick W. Limber, Patrick L. Barnard, Sean Vitousek, Li H. Erikson
2018, Journal of Geophysical Research F: Earth Surface (123) 1566-1589
Sea cliff retreat rates are expected to accelerate with rising sea levels during the 21st century. Here we develop an approach for a multi‐model ensemble that efficiently projects time‐averaged sea cliff retreat over multi‐decadal time scales and large (>50 km) spatial scales. The ensemble consists of five simple 1‐D models...
Analysis of mean seismic ground motion and its uncertainty based on the UCERF3 geologic slip rate model with uncertainty for California
Yuehua Zeng
2018, Seismological Research Letters (89) 1410-1419
The Uniform California Earthquake Rupture Forecast v.3 (UCERF3) model (Field et al., 2014) considers epistemic uncertainty in fault‐slip rate via the inclusion of multiple rate models based on geologic and/or geodetic data. However, these slip rates are commonly clustered about their mean value and do not reflect the broader distribution...
Landslides triggered by the 14 November 2016 Mw 7.8 Kaikōura Earthquake, New Zealand
C. Massey, D. Townsend, Ellen Rathje, Kate E. Allstadt, B. Lukovic, Yoshihiro Kaneko, Brendon A. Bradley, J. Wartman, Randall W. Jibson, D. N. Petley, Nick Horspool, I. Hamling, J. Carey, S. Cox, John Davidson, S. Dellow, Jonathan W. Godt, Christopher Holden, Katherine D. Jones, Anna E. Kaiser, M. Little, B. Lyndsell, S. McColl, R. Morgenstern, Francis K. Rengers, D. Rhoades, B. Rosser, D. Strong, C. Singeisen, M. Villeneuve
2018, Bulletin of the Seismological Society of America (108) 1630-1648
The 14 November 2016 Mw">MwMw 7.8 Kaikōura earthquake generated more than 10,000 landslides over a total area of about 10,000  km2"><span id="MathJax-Span-17"...
Reverse weathering in marine sediments and the geochemical cycle of potassium in seawater: Insights from the K isotopic composition (41K/39K) of deep-sea pore-fluids
Danielle P. Santiago Ramos, Leah E. Morgan, Nicholas S. Lloyd, John A. Higgins
2018, Geochimica et Cosmochimica Acta (236) 99-120
In situ Al-silicate formation, also known as “reverse weathering,” is an important sink of many of the major and minor cations in seawater (e.g. Mg, K, and Li). However, the importance of this sink in global geochemical cycles and isotopic budgets of these elements remains poorly constrained. Here, we report on the...
Respiratory hazard assessment of combined exposure to complete gasoline exhaust and respirable volcanic ash in a multicellular human lung model at the air-liquid interface
Ines Tomasek, Claire J. Horwell, Christoph Bisig, David Damby, Pierre Comte, Jan Czerwinski, Alke Petri-Fink, Martin J D Clift, Barbara Drasler, Barbara Rothen-Rutishauer
2018, Environmental Pollution (238) 977-987
Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases....
Hydrological regime and climate interactively shape riparian vegetation composition along the Colorado River, Grand Canyon
Bradley J. Butterfield, Emily C. Palmquist, Barbara Ralston
2018, Applied Vegetation Science (21) 572-583
QuestionHow closely do riparian plant communities track hydrological and climatic variation in space, and how do interactions among hydrological and climatic filters influence success of flow management strategies?LocationGrand Canyon, Arizona, USA.MethodsMulti‐year vegetation surveys were conducted across three hydrological...
A method to value nature-related webcam viewing: The value of virtual use with application to brown bear webcam viewing
John B. Loomis, Leslie Richardson, Christopher Huber, Jeffrey Skibins, Ryan Sharp
2018, Journal of Environmental Economics and Policy (7) 452-462
There are an estimated 16,000 nature related remote web cameras that provide users around the world with an opportunity to view wildlife. Because there is no monetary price to view the webcams, we utilise variations in the viewers’ opportunity cost of time to estimate consumer surplus. We apply this model...
A framework for identifying and characterising coral reef “oases” against a backdrop of degradation
James R. Guest, Peter J. Edmunds, Ruth D. Gates, Ilsa B. Kuffner, Andreas J Andersson, Brian B. Barnes, Iliana Chollett, Travis A. Courtney, Robin Elahi, Kevin Gross, Elizabeth A. Lenz, Satoshi Mitarai, Peter J. Mumby, Hannah R. Nelson, Britt A. Parker, Hollie M. Putnam, Caroline S. Rogers, Lauren T. Toth
2018, Journal of Applied Ecology (55) 2865-2875
Human activities have led to widespread ecological decline; however, the severity of degradation is spatially heterogeneous due to some locations resisting, escaping, or rebounding from disturbances.We developed a framework for identifying oases within coral reef regions using long‐term monitoring data. We calculated standardised estimates of coral cover (z‐scores) to...
Adaptation with climate uncertainty: An examination of agricultural land use in the United States
Jianhong E. Mu, Bruce A. McCarl, Benjamin M. Sleeter, John T. Abatzoglou, Hongliang Zhang
2018, Land Use Policy (77) 392-401
This paper examines adaptation responses to climate change through adjustment of agricultural land use. The climate drivers we examine are changes in long-term climate normals (e.g., 10-year moving averages) and changes in inter-annual climate variability. Using US county level data over 1982 to 2012 from Census of Agriculture, we find...
Estimating lag to peak between rainfall and peak streamflow with a mixed-effects model
Pamela J. Lombard, David Holtschlag
2018, Journal of the American Water Resources Association (JAWRA) (54) 949-961
We test the use of a mixed-effects model for estimating lag to peak for small basins in Maine (drainage areas from 0.8 to 78 km2). Lag to peak is defined as the time between the center of volume of the excess rainfall during a storm event and the resulting peak...
Suspended-sediment concentrations and loads in the lower Mississippi and Atchafalaya rivers decreased by half between 1980 and 2015
Scott Mize, Jennifer C. Murphy, Timothy H. Diehl, Dennis K. Demcheck
2018, Journal of Hydrology (564) 1-11
The Weighted Regressions on Time, Discharge, and Season (WRTDS) model was used to derive estimates of suspended-sediment concentration (SSC) and suspended-sediment load (SSL), their dependence on discharge, and their trends with confidence intervals, for one site each on the lowermost Mississippi...
Integrating animal movement with habitat suitability for estimating dynamic migratory connectivity
Marielle L. van Toor, Bart Kranstauber, Scott H. Newman, Diann J. Prosser, John Y. Takekawa, Georgios Technitis, Robert Weibel, Martin Wikelski, Kamran Safi
2018, Landscape Ecology (33) 879-893
ContextHigh-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of...
Reductive dechlorination rates of 4,4′-DDE (1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene) in sediments of the Palos Verdes Shelf, CA
Robert P. Eganhouse, Christopher R. Sherwood, James Pontolillo, Brian Edwards, Patrick J. Dickhudt
2018, Marine Chemistry (203) 10-21
Wastes from the world's largest manufacturer of DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) were released into the Los Angeles County municipal sewer system from 1947 to 1971. Following primary treatment, the effluent was discharged through a submarine outfall system whereupon a portion of the DDT and associated degradation products were deposited in sediments of...
Quantifying anthropogenic contributions to century-scale groundwater salinity changes, San Joaquin Valley, California, USA
Jeffrey A. Hansen, Bryant C. Jurgens, Miranda S. Fram
2018, Science of the Total Environment (642) 125-136
Total dissolved solids (TDS) concentrations in groundwater tapped for beneficial uses (drinking water, irrigation, freshwater industrial) have increased on average by about 100 mg/L over the last 100 years in the San Joaquin Valley, California (SJV). During this period land use in the SJV changed from natural vegetation and dryland...
Harnessing big data to rethink land heterogeneity in Earth system models
Nathaniel W. Chaney, Marjolein H. J. Van Huijgevoort, Elena Shevliakova, Sergey Malyshev, Paul C. D. Milly, Paul P. G. Gauthier, Benjamin N. Sulman
2018, Hydrology and Earth System Sciences (22) 3311-3330
The continual growth in the availability, detail, and wealth of environmental data provides an invaluable asset to improve the characterization of land heterogeneity in Earth system models – a persistent challenge in macroscale models. However, due to the nature of these data (volume and complexity) and computational constraints, these data...
Exposure to human-associated chemical markers of fecal contamination and self-reported illness among swimmers at recreational beaches
Melanie D Napier, Charles Poole, Jill R Stewart, David J Weber, Susan T. Glassmeyer, Dana W. Kolpin, Edward Furlong, Alfred P Dufour, Timothy J. Wade
2018, Environmental Science & Technology (52) 7513-7523
Anthropogenic chemicals have been proposed as potential markers of human fecal contamination in recreational water. However, to date, there are no published studies describing their relationships with illness risks. Using a cohort of swimmers at seven U.S. beaches, we examined potential...
Rapid crop cover mapping for the conterminous United States
Devendra Dahal, Bruce K. Wylie, Daniel Howard
2018, Scientific Reports (8)
Timely crop cover maps with sufficient resolution are important components to various environmental planning and research applications. Through the modification and use of a previously developed crop classification model (CCM), which was originally developed to generate historical annual crop cover maps, we hypothesized that such crop cover maps could be...
Dryland photoautotrophic soil surface communities endangered by global change
Emilio Rodriguez-Caballero, Jayne Belnap, Burkhard Budel, Paul J. Crutzen, Meinrat O. Andreae, Ulrich Poschl, Bettina Weber
2018, Nature Geoscience (11) 185-189
Photoautotrophic surface communities forming biological soil crusts (biocrusts) are crucial for soil stability as well as water, nutrient and trace gas cycling at regional and global scales. Quantitative information on their global coverage and the environmental factors driving their distribution patterns, however, are not readily available. We use observations and...
Seagrass impact on sediment exchange between tidal flats and salt Marsh, and the sediment budget of shallow bays
Carmine Donatelli, Neil Kamal Ganju, Sergio Fagherazzi, Nicoletta Leonardi
2018, Geophysical Research Letters (45) 4933-4943
Seagrasses are marine flowering plants that strongly impact their physical and biological surroundings and are therefore frequently referred to as ecological engineers. The effect of seagrasses on coastal bay resilience and sediment transport dynamics is understudied. Here we use six historical maps of seagrass distribution in Barnegat Bay, USA, to investigate...
Preface to the Focus Section on the Collaboratory for the Study of Earthquake Predictability (CSEP): New results and future directions
Andrew J. Michael, Maximillian J. Werner
2018, Seismological Research Letters (89) 1226-1228
The Collaboratory for the Study of Earthquake Predictability (CSEP; Jordan, 2006) carries out fully prospective tests of earthquake forecasts, using fixed and standardized statistical tests and authoritative data sets, to assess the predictive skill of forecast models and to make objective comparisons between models. CSEP conducts...
