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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Estimating biogeochemical rates using a computationally efficient Lagrangian approach Estimating biogeochemical rates using a computationally efficient Lagrangian approach
Nutrient concentrations in many estuaries have increased over the past century due to increases in wastewater discharge and increased agricultural intensity, contributing to multiple environmental problems. Numerous biogeochemical and physical processes in estuaries influence nutrient concentrations during transport, resulting in complex spatial and temporal variability and challenges...
Authors
Edward Gross, Rusty Holleman, Wim Kimmerer, Tamara E. C. Kraus, Brian A. Bergamaschi, Scott Burdick-Yahya, David Senn
Computationally efficient emulation of spheroidal elastic deformation sources using machine learning models: a Gaussian-process-based approach Computationally efficient emulation of spheroidal elastic deformation sources using machine learning models: a Gaussian-process-based approach
Elastic continuum mechanical models are widely used to compute deformations due to pressure changes in buried cavities, such as magma reservoirs. In general, analytical models are fast but can be inaccurate as they do not correctly satisfy boundary conditions for many geometries, while numerical models are slow and may require specialized expertise and software. To overcome these...
Authors
Kyle R. Anderson, Mengyang Gu
Siting considerations for satellite observation of river discharge Siting considerations for satellite observation of river discharge
With growing global capability for satellite measurement of river discharge (flow) comes a need to understand and reduce error in satellite-based discharge measurements. Satellite-based discharge estimates are based on measurements of water surface width, elevation, slope, and potentially velocity. Site selection is important for reducing error and uncertainty in both conventional and...
Authors
Jack R. Eggleston, Christopher A. Mason, David M. Bjerklie, Michael T. Durand, Robert W. Dudley, Merritt Elizabeth Harlan
A reproducible manuscript workflow with a Quarto template A reproducible manuscript workflow with a Quarto template
Scientists and resource managers increasingly use Markdown-based tools to create reproducible reports and manuscripts. These workflows allow people to use standardized methods that are more reproducible, efficient, and transparent than other standard office tools. We present a Quarto template and demonstrate how this template may be used for a journal, the Journal of Fish and Wildlife...
Authors
Richard A. Erickson, Althea A. Archer, Michael N. Fienen
Assessing the vertical accuracy of digital elevation models by quality level and land cover Assessing the vertical accuracy of digital elevation models by quality level and land cover
The vertical accuracy of elevation data in coastal environments is critical because small variations in elevation can affect an area’s exposure to waves, tides, and storm-related flooding. Elevation data contractors typically quantify the vertical accuracy of lidar-derived digital elevation models (DEMs) on a per-project basis to gauge whether the datasets meet quality and accuracy...
Authors
Minoo Han, Nicholas Enwright, Dean B. Gesch, Jason M. Stoker, Jeffrey J. Danielson, Christopher J. Amante
A spatial machine learning model developed from noisy data requires multiscale performance evaluation: Predicting depth to bedrock in the Delaware River Basin, USA A spatial machine learning model developed from noisy data requires multiscale performance evaluation: Predicting depth to bedrock in the Delaware River Basin, USA
Spatial machine learning models can be developed from observations with substantial unexplainable variability, sometimes called ‘noise’. Traditional point-scale metrics (e.g., R2) alone can be misleading when evaluating these models. We present a multi-scale performance evaluation (MPE) using two additional scales (distributional and geostatistical). We apply the MPE framework to...
Authors
Phillip J. Goodling, Kenneth Belitz, Paul E. Stackelberg, Brandon J. Fleming
Back from the brink: Estimating daily and annual abundance of natural-origin salmon smolts from 30-years of mixed-origin capture-recapture data Back from the brink: Estimating daily and annual abundance of natural-origin salmon smolts from 30-years of mixed-origin capture-recapture data
Evaluating the status and trends of natural-origin anadromous fish populations over time requires robust estimates of out-migrating juvenile abundance. Information on abundance is typically acquired by capturing actively migrating fish as they pass stationary monitoring platforms. Challenges to estimation include protracted migration timing, temporally varying capture probabilities and...
Authors
Dalton Hance, John Plumb, Russell Perry, Kenneth Tiffan
Modeling the mid-Piacenzian warm climate using the water isotope-enabled Community Earth System Model (iCESM1.2-ITPCAS) Modeling the mid-Piacenzian warm climate using the water isotope-enabled Community Earth System Model (iCESM1.2-ITPCAS)
The mid-Piacenzian Warm Period (MPWP, ~ 3.264–3.025 Ma) is the most recent example of a persistently warmer climate in equilibrium with atmospheric CO2 concentrations similar to today. Towards studying patterns and dynamics of a warming climate the MPWP is often compared to today. Following the Pliocene Model Intercomparison Project, Phase 2 (PlioMIP2) protocol we prepare a water isotope...
Authors
Yong Sun, Baohuang Su, Harry J. Dowsett, Haibin Wu, Jun Hu, Christian Stepanek, Zhongyu Xiong, Xiayu Yuan, Gilles Ramstein
Viability modeling for decision support with limited data: A lizard case study Viability modeling for decision support with limited data: A lizard case study
Plateau spot-tailed earless lizards, Holbrookia lacerata, are a species of ground lizard in central Texas that are under review for listing as endangered under the US Endangered Species Act, but heretofore no predictive models of population dynamics or viability have been developed. We used limited available data and published demographic rates in a PVA model to predict future status of...
Authors
Ashley B.C. Goode, Nathan Allan, Conor P. McGowan
Alaskan glacial dust is an important iron source to surface waters of the Gulf of Alaska Alaskan glacial dust is an important iron source to surface waters of the Gulf of Alaska
This work evaluates glacial dust as a source of sediment, and associated iron (Fe), to the Fe-limited Gulf of Alaska (GoA). A reanalysis of GoA sediment data, using rare earth elements and thorium as provenance tracers, suggests a flux to the ocean surface of Copper River (AK) glacial dust, and associated Fe, that is comparable to the flux of dust from Asia, at least 1,000 km from the...
Authors
John Crusius, Carsten Lao, Thomas M. Holmes, J. W. Murray
Iron oxyhydroxide-rich hydrothermal deposits at the high-temperature Fåvne vent field, Mohns Ridge Iron oxyhydroxide-rich hydrothermal deposits at the high-temperature Fåvne vent field, Mohns Ridge
The recently discovered Fåvne vent field, located at 3,040 m depth on the slow-spreading Mohns mid-ocean ridge between Greenland and Norway, is a high-temperature (≥250°C) vent field that is characterized by Fe oxyhydroxide-rich and S-poor chimneys and mounds. The vent field is located on both the hanging wall and footwall of a normal fault with a ∼1.5 km throw that forms the western...
Authors
Caroline Gini, John Jamieson, Eoghan P. Reeves, Amy Gartman, Thibaut Barreyre, Michael G. Babechuk, Steffen L. Jorgensen, Katleen Robert
Prediction of regional broadband strong ground motions using a teleseismic source model of the 18 April 2014 Mw 7.3 Papanoa, Mexico, earthquake Prediction of regional broadband strong ground motions using a teleseismic source model of the 18 April 2014 Mw 7.3 Papanoa, Mexico, earthquake
To estimate predicted ground motion from a teleseismic slip model, we use a low‐ and high‐frequency hybrid method to simulate the regional, strong ground motions observed following the 18 April 2014 moment magnitude (Mw) 7.3 Papanoa, Mexico, earthquake. To generate the regional ground motion at low frequencies (1 Hz) are added using a 1D full‐wave propagation code that estimates...
Authors
Carlos Mendoza, Stephen H. Hartzell, Leonardo Ramirez-Guzman, R. Martinez-Lopez