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USGS2020

Spatially referenced models of streamflow and nitrogen, phosphorus, and suspended-sediment loads in streams of the Pacific region of the United States

Although spatial information describing the supply and quality of surface water is critical for managing water resources for human uses and for ecological health, monitoring is expensive and cannot typically be done over large scales or in all streams or waterbodies. To address the need for such data, the U.S. Geological Survey developed SPAtially Referenced Regression On Watershed attributes (SPARROW) for the Pacific region of the U.S. for streamflow and three water-quality constituents–total nitrogen, total phosphorus, and suspended sediment, based on a decadal time frame centered on the year 2012. The domain for these models included the Columbia River basin, the Puget Sound, the coastal drainages of Washington, Oregon, and California, and the Central Valley of California. Landscape runoff (represented by the difference between precipitation and evapotranspiration) was the largest source of streamflow, wastewater discharge, and atmospheric deposition were the largest contributors to total nitrogen yield from the Pacific region, wastewater discharge was the largest contributor to total phosphorus yield, and forest land was the largest contributor to suspended-sediment yield. Watersheds with relatively high water yields also generally had relatively high yields of total nitrogen, total phosphorous, and suspended sediment–except where there were large contributions from developed land and wastewater discharge. The data used in this study, including many that improved upon existing national data or were compiled specifically for the Pacific region, characterized the complex hydrologic and water-quality conditions in the region more completely than previous models. By using these new datasets, this investigation was able to account for the complex network of water diversions and transfers, quantify the contribution of nutrients from different sources of livestock manure, discern a signal from unpaved logging roads in the suspended-sediment yields from forested coastal watersheds, show how recent wildfire disturbance influences phosphorus and sediment delivery to streams, and how sediment delivery to streams is also sensitive to the intensity of cattle grazing. The results from this study could complement research and inform water-quality management activities in the Pacific region. Examples might include identifying potentially impaired waterbodies and guiding remediation efforts where impairment has been documented, explaining the spatial patterns in harmful algal blooms, and providing estimates of sediment and nutrient loadings to Pacific coast estuaries where such data are scarce or non-existent.

Pacific Region↗

USGS2022

Linear regression model documentation for computing water-quality constituent concentrations using continuous real-time water-quality data for the Republican River, Clay Center, Kansas, July 2018 through March 2021

The Republican River is the primary inflow to Milford Lake and drains areas of Kansas, Nebraska, and Colorado. Milford Lake has been listed as impaired and designated hypereutrophic by the Kansas Department of Health and Environment because of excessive nutrient loading. Milford Lake had confirmed harmful algal blooms every summer from 2011 through 2017 and in 2020 and 2021. In the lower Republican River drainage basin, the Regional Conservation Partnership Program, administered by the Natural Resources Conservation Service, provides reimbursement to agricultural producers that implement best management practices intended to decrease sediment and nutrient runoff and loading into Milford Lake. Sediment and nutrient loads could potentially be driving factors in the development of harmful algal blooms in the reservoir. Since July 2018, the U.S. Geological Survey, in cooperation with the Kansas Water Office, has collected continuous and discrete water-quality data at the Republican River at Clay Center, Kansas, streamgage (U.S. Geological Survey station 06856600), which is about 15 river miles upstream from Milford Lake. This report documents site-specific regression models for the computation of continuous concentrations of suspended sediment, total nitrogen, total phosphorus, and total carbon developed using continuous and discrete data collected from July 24, 2018, the date of continuous water-quality monitor installation, through March 31, 2021. The objective of this study is to characterize sediment and nutrient transport in the Milford Lake drainage basin before, during, and after best management practice implementation using the models described in this report. The explanatory variable turbidity explained a high amount (72–96 percent) of the variance in suspended-sediment, total nitrogen, total phosphorus, and total carbon concentrations. Statistical plots for the four selected models showed the desired normality and homoscedasticity in residuals, and model standard error ratios indicated that recomputing each selected model after removing a randomly selected 10 percent of the data did not substantially change model coefficients.

Kansas↗

USGS2022

A computer-aided approach for adapting stage-discharge ratings and characterizing uncertainties of streamflow data with discrete measurements

Relations between stage (water level) and discharge of streamflow through a natural channel are the result of time-varying processes, which are commonly described by time-varying stage-discharge ratings. Hydrographers with the U.S. Geological Survey successfully maintain the accuracy of streamflow data by manually applying time-tested approaches to adapt ratings to temporal changes in hydraulic conditions. The difficulty with the manual approach is that it is a subjective, time-consuming process that requires considerable skill and experience to implement. In addition, manual adjustments of ratings make quantification of resulting streamflow data uncertainties problematic. A computer-aided adaptive stage-discharge estimation approach is proposed to track sequential changes in the relation between stage and discharge at continuous-record streamgages. In this report, adaptations are based strictly on discrete measurement data that are then used to compute the magnitudes and uncertainties of streamflow. The approach entails the parameterization of a cubic regression spline (CRS) for the stage-discharge relation based on an existing rating or on a set of discrete measurements. A state-space model is then parameterized to track temporal changes in stage-discharge relations beginning with the initial CRS parameterization using discrete measurements. Finally, Kalman estimation is used with the state-space model to estimate the magnitude and uncertainty of flows. In a case study using data from streamgage U.S. Geological Survey 04122500 Marquette River at Scottville, Michigan, a five-parameter CRS model was estimated from data in an existing stage-discharge rating to provide an initial CRS parameter set for a state-space model. The initial CRS parameters were updated sequentially in a state-space model based on periodic discrete measurements of stage and discharge that spanned a 30-year period for this analysis. Additional analysis is needed to determine the timing of rapidly varying shifts more precisely in stage-discharge relations than the relatively infrequent discrete measurements currently enabled. Unit streamflow estimates based on flow in a local streamgaging network may provide a basis for adapting a stage-discharge rating at unit time intervals by augmenting discrete measurement data within the state-space model.

Michigan↗

USGS2024

External quality-assurance project report for the National Atmospheric Deposition Program National Trends Network and Mercury Deposition Network, 2021–22

The U.S. Geological Survey Precipitation Chemistry Quality Assurance project (PCQA) operated five distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program (NADP) National Trends Network (NTN) and Mercury Deposition Network (MDN) during 2021–22. The NTN programs included (1) a field audit program to evaluate sample contamination and stability, (2) an interlaboratory-comparison program to evaluate analytical laboratory performance, and (3) a colocated sampler program to estimate overall variability of NTN wet-deposition measurements, and the MDN programs included the (4) system blank program to evaluate sample contamination and stability and (5) an interlaboratory-comparison program. The results indicated increased levels of sample contamination compared to previous years for NTN samples and decreased contamination in MDN samples. Strong analytical laboratory performance with low overall variability and bias in concentration data was indicated for the NTN Central Analytical Laboratory. Slight perturbations in contamination levels in NTN samples and in analytical performance for MDN are considered inconsequential. The colocated sampler program results indicated overall variability in NTN data to range from 0 to 30.3 percent for cations, 1.6 to 11.4 percent for ammonium, 0.8 to 20.2 percent for anions, 10.3 to 17.2 percent for hydrogen-ion concentration, and 1.5 to 12.2 percent for specific conductance. The PCQA results indicate that NADP data continue to be of sufficient quality for applications in independent research and NADP data products, including spatial interpolations and time trends for chemical constituents in wet deposition. Small shifts in data quality indicated by the 2021–22 PCQA results are included to be used for interpretation of the NADP data products.

Scientific Investigations Report↗

USGS2018

Separable correlation and maximum likelihood

We consider estimation of the covariance matrix of a multivariate normal distribution when the correlation matrix is separable in the sense that it factors as a Kronecker product of two smaller matrices. A computationally convenient coordinate descent-type algorithm is developed for maximum likelihood estimation. Simulations indicate our method often gives smaller estimation error than some common alternatives when correlation is separable, and that correctly sized tests for correlation separability can be obtained using a parametric bootstrap. Using dissolved oxygen data from the Upper Mississippi River, we illustrate how our model can lead to interesting scientific findings that may be missed when using competing models.

arXiv↗

USGS2004

Hierarchial mark-recapture models: a framework for inference about demographic processes

The development of sophisticated mark-recapture models over the last four decades has provided fundamental tools for the study of wildlife populations, allowing reliable inference about population sizes and demographic rates based on clearly formulated models for the sampling processes. Mark-recapture models are now routinely described by large numbers of parameters. These large models provide the next challenge to wildlife modelers: the extraction of signal from noise in large collections of parameters. Pattern among parameters can be described by strong, deterministic relations (as in ultrastructural models) but is more flexibly and credibly modeled using weaker, stochastic relations. Trend in survival rates is not likely to be manifest by a sequence of values falling precisely on a given parametric curve; rather, if we could somehow know the true values, we might anticipate a regression relation between parameters and explanatory variables, in which true value equals signal plus noise. Hierarchical models provide a useful framework for inference about collections of related parameters. Instead of regarding parameters as fixed but unknown quantities, we regard them as realizations of stochastic processes governed by hyperparameters. Inference about demographic processes is based on investigation of these hyperparameters. We advocate the Bayesian paradigm as a natural, mathematically and scientifically sound basis for inference about hierarchical models. We describe analysis of capture-recapture data from an open population based on hierarchical extensions of the Cormack-Jolly-Seber model. In addition to recaptures of marked animals, we model first captures of animals and losses on capture, and are thus able to estimate survival probabilities w (i.e., the complement of death or permanent emigration) and per capita growth rates f (i.e., the sum of recruitment and immigration rates). Covariation in these rates, a feature of demographic interest, is explicitly described in the model.

Animal Biodiversity and Conservation↗

USGS2025

Integrated Hydro-terrestrial Modeling 2.0: Progress and path forward on building a national capability

Growing societal pressures on U.S. water resources and the challenges inherent in understanding how future water risks may evolve are driving major investments to improve our knowledge of the integrated water cycle. This improved understanding as captured in innovations in our data, knowledge, and modeling capabilities, needs to be accelerated through better integration and coordination across scientific disciplines, programs, and U.S. agencies. The Integrated Hydro-Terrestrial Modeling (IHTM) community holds promise to accelerate the progress required to manage the U.S. water resources sustainably, equitably, and effectively. The U.S. Global Change Research Program (USGCRP) coordinates research on the impacts of global change on the water cycle through interagency collaboration. USGCRP agencies and their partners jointly held the IHTM 2.0 workshop for U.S. federal and non-federal scientists and managers in fall 2023, aiming to advance community modeling and integrated water resources management capabilities following open science principles. This workshop focused on developing both national and regional testbeds that employ state-of-the-art modeling approaches to explore gaps and opportunities for improving the representation and extensibility of hydrologic processes and modeling. Integrated regional testbeds in Mid-Atlantic, Great Lakes, Colorado River Basin, and Gulf Coast/Mississippi regions were proposed to leverage existing investments and seek actionable collaboration on issues such as water extremes, water quality, water use, and urbanization. Collaborations focused on advancing iterative cycles of model development and testing offer a means for regional scale studies to inform national scale modeling applications and yield nationally consistent modeling frameworks that are also locally relevant. This presentation will highlight key takeaways, findings, and future directions for the IHTM community that have been laid out in the IHTM 2.0 workshop report.

Report↗

USGS2006

Estimation of nonpoint-source loads of total nitrogen, total phosphorous, and total suspended solids in the Black, Belle, and Pine River basins, Michigan, by use of the PLOAD model

The Lake St. Clair Regional Monitoring Project partners planned a 3-year assessment study of the surface water in the Lake St. Clair drainage basins in Michigan. This study included water-quality monitoring and analysis, collection of discrete (grab) and automatic water-quality samples, monitoring of bacteria, and the creation of a database to store all relevant data collected from past and future field-data-collection programs. In cooperation with the Lake St. Clair Monitoring Project, the U.S. Geological Survey assessed nonpoint-source loads of nutrients and total suspended solids in the Black, Belle, and Pine River basins. The principal tool for the assessment study was the USEPA’s PLOAD model, a simplified GIS-based numerical program that generates gross estimates of pollutant loads. In this study, annual loads were computed for each watershed using the USEPA’s Simple Method, which is based on scientific studies showing a correlation between different land-use types and loading rates. The two land-use data sets used in the study (representing 1992 and 2001) show a maximum of 0.02-percent change in any of the 15 land use categories between the two timeframes. This small change in land use is reflected in the PLOAD results of the study area between the two time periods. PLOAD model results for the 2001 land-use data include total-nitrogen loads from the Black, Belle, and Pine River basins of approximately 495,599 lb/yr, 156,561 lb/yr, and 121,212 lb/yr, respectively; total-phosphorus loads of 80,777 lb/yr, 25,493 lb/yr, and 19,655 lb/yr, respectively; and total-suspended-solids loads of 5,613,282 lb/yr, 1,831,045 lb/yr, and 1,480,352 lb/yr, respectively. The subbasins in the Black, Belle, and Pine River basin with comparatively high loads are characterized by comparatively high percentages of industrial, commercial, transportation, or residential land use. The results from the PLOAD model provide useful information about the approximate average annual loading rates from the three study basins. In particular, the results identify subbasins with comparatively high loading rates per square mile. This could aid water-resources managers and planners in evaluation of the effectiveness of public expenditures for water-quality improvements, assessment of progress towards achieving established water-quality goals, and planning of preventive actions.

Michigan↗

USGS2002

Magnetic anomaly map of North America

This digital Magnetic Anomaly database and map for the North American continent is the result of a joint effort by the Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM). The database and map represent a substantial upgrade from the previous compilation of Magnetic Anomaly data for North America, now over a decade old (Committee for the Magnetic Anomaly Map of North America, 1987). This integrated, readily accessible, modern digital database of magnetic anomaly data will be a powerful tool for further evaluation of the structure, geologic processes, and tectonic evolution of the continent and may also be used to help resolve societal and scientific issues that span national boundaries. The North American magnetic anomaly map derived from the digital database provides a comprehensive magnetic view of continental-scale trends not available in individual data sets, helps link widely separated areas of outcrop, and unifies disparate geologic studies. This booklet outlines the data processing and compilation procedures used to produce the magnetic anomaly database and map that accompany this booklet.

Special Map↗

USGS2005

Topographic map of the Coronae Montes region of Mars - MTM 500k -35/087E OMKTT

This map is part of a series of topographic maps of areas of special scientific interest on Mars. The topography was compiled photogrammetrically using Viking Orbiter stereo image pairs. The contour interval is 250 m. Horizontal and vertical control was established using the USGS Mars Digital Image Model 2.0 (MDIM 2.0) and data from the Mars Orbiter Laser Altimeter (MOLA).

Scientific Investigations Map↗

USGS1998

The Soufriere Hills eruption, Montserrat, British West Indies: Introduction to special section, part 1

The special section on the eruption of Soufriere Hills volcano is a collection of 24 papers that summarises the early scientific work of the Montserrat Volcano Observatory. Part 1 of the special section, published in a previous issue of GRL , provided a sampling of the multidisciplinary investigations undertaken at Montserrat. The papers published in Part 1 included an overview of the eruption, investigations on seismicity, ground deformation studies, and petrology. The papers of this issue comprise Part 2 of the special section. These papers also cover a broad spectrum of topics, including various topics in seismology, petrology, pyroclastic flow models, gas chemistry, hydrothermal systems, and tsunami models. In general, papers in Part 1 may be said to be more observational- or data-orientated, and those of Part 2 more model-orientated, but indeed there is much overlap of descriptive material, data, and modelling within the individual contributions. Considered in total the collection presents a representative summary of the scientific effort carried out in Montserrat through much of 1997.

Geophysical Research Letters↗

USGS1965

Resource understanding: a challenge to aerial methods

Aerial survey methods are speeding acquisition of survey data needed to provide and manage the nation's resources. These methods have been applied to topographic mapping for a number of years and the record clearly shows their advantages in terms of cost and speed in contrast to the ground methods that have been historically employed. Limited use is now being made of aerial methods to assist cadastral surveys, in location, acquisition and development of National Parks, in mapping the geology of the nation, in locating and developing water resources, and in surveys of the oceans. It is the purpose of this paper to call attention to these uses and to encourage the scientific community to further refine aerial methods so that their use may be increased and the veracity of data improved.

Photogrammetric Engineering↗

USGS2015

Formulating the American Geophysical Union's Scientific Integrity and Professional Ethics Policy: Challenges and lessons learned

Creating an ethics policy for a large, diverse geosciences organization is a challenge, especially in the midst of the current contentious dialogue in the media related to such issues as climate change, sustaining natural resources, and responding to natural hazards. In 2011, the American Geophysical Union (AGU) took on this challenge, creating an Ethics Task Force to update their ethics policies to better support their new Strategic Plan and respond to the changing scientific research environment. Dialogue with AGU members and others during the course of creating the new policy unveiled some of the following issues to be addressed. Scientific results and individual scientists are coming under intense political and public scrutiny, with the efficacy of the science being questioned. In some cases, scientists are asked to take sides and/or provide opinions on issues beyond their research, impacting their objectivity. Pressure related to competition for funding and the need to publish high quality and quantities of papers has led to recent high-profile plagiarism, data fabrication, and conflict of interest cases. The complexities of a continuously advancing digital environment for conducting, reviewing, and publishing science has raised concerns over the ease of plagiarism, fabrication, falsification, inappropriate peer review, and the need for better accessibility of data and methods. Finally, students and scientists need consistent education and encouragement on the importance of ethics and integrity in scientific research. The new AGU Scientific Integrity and Ethics Policy tries to address these issues and provides an inspirational code of conduct to encourage a responsible, positive, open, honest scientific research environment.

Book chapter↗

USGS1989

Water-related scientific activities of the U.S. Geological Survey in Nevada, fiscal years 1985-89

The U.S. Geological Survey has been collecting water resources data in Nevada since 1890. Most of the projects in the current Nevada District program can be classified as either basic-data acquisition (about 25%) or hydrologic interpretation (about 75 %). About 52% of the activities are supported by cooperative agreements with State and local agencies. Technical projects supported by other Federal agencies make up about 23% of the program, and the remaining 25% consists of data collection, research, and interpretive projects supported directly by the U.S. Geological Survey. Water conditions in Nevada during the 4 years covered by this report were by no means average, with 1 very wet year (1986) and 2 very dry years (1987-88). The major water resources issues include: water allocation in the Truckee-Carson River basin; irrigation return flow contamination of the Stillwater Wildlife Management Area; effects of weapons testing at the Nevada Test Site; assessment of potential long-term impacts of the proposed Yucca Mountain Nuclear Waste Repository; and drought. Future water-resources issues in Nevada are likely to center on water supply for and the environmental effects of, the rapidly growing population centers at Las Vegas, Reno, and Elko; impacts of operations at the Nevada Test Site; management of interstate rivers such as the Truckee and Colorado Rivers; hydrologic and environmental impacts at heavily mined areas; and water quality management in the Lake Tahoe Basin. (Thacker-USGS-WRD)

Open-File Report↗

USGS2008

Landsat continuity: Issues and opportunities for land cover monitoring

Initiated in 1972, the Landsat program has provided a continuous record of earth observation for 35 years. The assemblage of Landsat spatial, spectral, and temporal resolutions, over a reasonably sized image extent, results in imagery that can be processed to represent land cover over large areas with an amount of spatial detail that is absolutely unique and indispensable for monitoring, management, and scientific activities. Recent technical problems with the two existing Landsat satellites, and delays in the development and launch of a successor, increase the likelihood that a gap in Landsat continuity may occur. In this communication, we identify the key features of the Landsat program that have resulted in the extensive use of Landsat data for large area land cover mapping and monitoring. We then augment this list of key features by examining the data needs of existing large area land cover monitoring programs. Subsequently, we use this list as a basis for reviewing the current constellation of earth observation satellites to identify potential alternative data sources for large area land cover applications. Notions of a virtual constellation of satellites to meet large area land cover mapping and monitoring needs are also presented. Finally, research priorities that would facilitate the integration of these alternative data sources into existing large area land cover monitoring programs are identified. Continuity of the Landsat program and the measurements provided are critical for scientific, environmental, economic, and social purposes. It is difficult to overstate the importance of Landsat; there are no other systems in orbit, or planned for launch in the short-term, that can duplicate or approach replication, of the measurements and information conferred by Landsat. While technical and political options are being pursued, there is no satellite image data stream poised to enter the National Satellite Land Remote Sensing Data Archive should system failures occur to Landsat-5 and -7.

Remote Sensing of Environment↗

USGS2011

Geomagnetic referencing in the arctic environment

Geomagnetic referencing is becoming an increasingly attractive alternative to north-seeking gyroscopic surveys to achieve the precise wellbore positioning essential for success in today's complex drilling programs. However, the greater magnitude of variations in the geomagnetic environment at higher latitudes makes the application of geomagnetic referencing in those areas more challenging. Precise, real-time data on those variations from relatively nearby magnetic observatories can be crucial to achieving the required accuracy, but constructing and operating an observatory in these often harsh environments poses a number of significant challenges. Operational since March 2010, the Deadhorse Magnetic Observatory (DED), located in Deadhorse, Alaska, was created through collaboration between the United States Geological Survey (USGS) and a leading oilfield services supply company. DED was designed to produce real-time geomagnetic data at the required level of accuracy, and to do so reliably under the extreme temperatures and harsh weather conditions often experienced in the area. The observatory will serve a number of key scientific communities as well as the oilfield drilling industry, and has already played a vital role in the success of several commercial ventures in the area, providing essential, accurate data while offering significant cost and time savings, compared with traditional surveying techniques.

Alaska↗

USGS2006

Science for maintaining riverine ecosystems: Actions for the USGS identified in the workshop "Analysis of Flow and Habitat for Aquatic Communities"

Federal and state agencies need improved scientific analysis to support riverine ecosystem management. The ability of the USGS to integrate geologic, hydrologic, chemical, geographic, and biological data into new tools and models provides unparalleled opportunities to translate the best riverine science into useful approaches and usable information to address issues faced by river managers. In addition to this capability to provide integrated science, the USGS has a long history of providing long-term and nationwide information about natural resources. The USGS is now in a position to advance its ability to provide the scientific support for the management of riverine ecosystems. To address this need, the USGS held a listening session in Fort Collins, Colorado in April 2006. Goals of the workshop were to: 1) learn about the key resource issues facing DOI, other Federal, and state resource management agencies; 2) discuss new approaches and information needs for addressing these issues; and 3) outline a strategy for the USGS role in supporting riverine ecosystem management. Workshop discussions focused on key components of a USGS strategy: Communications, Synthesis, and Research. The workshop identified 3 priority actions the USGS can initiate now to advance its capabilities to support integrated science for resource managers in partner government agencies and non-governmental organizations: 1) Synthesize the existing science of riverine ecosystem processes to produce broadly applicable conceptual models, 2) Enhance selected ongoing instream flow projects with complementary interdisciplinary studies, and 3) Design a long-term, watershed-scale research program that will substantively reinvent riverine ecosystem science. In addition, topical discussion groups on hydrology, geomorphology, aquatic habitat and populations, and socio-economic analysis and negotiation identified eleven important complementary actions required to advance the state of the science and to develop the tools for supporting decisions on riverine ecosystem management. These eleven actions lie within the continuum of Communications, Synthesis, and Research.

Open-File Report↗

USGS2019

A strategy for defining the reference for land health and degradation assessments

Much of the confusion about the definition of reference conditions for land health and degradation assessments is due to differences in policy and management objectives. Selection of a historic reference where it is not necessary, such as in the definition of future land degradation neutrality, can add significant cost and uncertainty to land management projects that require some knowledge of the current status of the land relative to its potential. This paper (1) provides a review of conditions under which historic reference information is and is not required to meet management and policy objectives, (2) summarizes current approaches to defining the reference for land health and degradation assessments, and (3) presents a protocol, “Describing Indicators of Rangeland Health” (DIRH) for collecting and organizing data that can be used to define a historic reference. This protocol builds on the framework and indicators presented in the “Interpreting Indicators of Rangeland Health” (IIRH). IIRH uses a combination of scientific and local knowledge to generate soil- and climate-specific assessments of three attributes of land health. It is used in a number of countries. In the United States, data are aggregated over 30,000 locations to provide national assessments.

Ecological Indicators↗