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At least 1,621 records · Page 90Linked to original sources

Groundwater availability of the Columbia Plateau Regional Aquifer System, Washington, Oregon, and Idaho

The Columbia Plateau Regional Aquifer System (CPRAS) covers about 44,000 square miles of southeastern Washington, northeastern Oregon, and western Idaho. The area supports a $6-billion per year agricultural industry, leading the Nation in production of apples, hops, and eight other commodities. Groundwater pumpage and surface-water diversions supply water to croplands that account for about 5 percent of the Nation’s irrigated lands. Groundwater also is the primary source of drinking water for the more than 1.3 million people in the study area. Increasing competitive demands for water for municipal, fisheries/ecosystems, agricultural, domestic, hydropower, and recreational uses must be met by additional groundwater withdrawals and (or) by changes in the way water resources are allocated and used throughout the hydrologic system. As of 2014, most surface-water resources in the study area were either over allocated or fully appropriated, especially during the dry summer season. In response to continued competition for water, numerous water-management activities and concerns have gained prominence: water conservation, conjunctive use, artificial recharge, hydrologic implications of land-use change, pumpage effects on streamflow, and effects of climate variability and change. An integrated understanding of the hydrologic system is important in order to implement effective water-resource management strategies that address these concerns. To provide information to stakeholders involved in water-management activities, the U.S. Geological Survey (USGS) Groundwater Resources Program assessed the groundwater availability as part of a national study of regional systems (U.S. Geological Survey, 2008). The CPRAS assessment includes: The present status of groundwater resources, How these resources have changed over time, and Development and application of tools to estimate system responses to stresses from future uses and climate variability and change. This effort builds on previous investigations, especially the USGS Columbia Plateau Regional Aquifer-System Analysis study (CP-RASA). A major product of this new assessment is a numerical groundwater-flow model of the system. The model was used to estimate water-budget components of the hydrogeologic units composing the groundwater system, and to evaluate groundwater availability under existing land- and water-use conditions and a possible future climate scenario representing an increase in pumpage demand due to a warming climate. Information from this study also allowed for analysis of: The CPRAS for predevelopment times (pre-1920), Variations from 1920 through 2007, Conditions during 1985–2007 (referred to as “existing conditions”), and Changes in the system from predevelopment times. The model also is a useful tool for investigating water supply, water demand, management strategies, groundwater-surface water exchanges, and potential effects of changing climate on the hydrologic system.

Idaho, Oregon, Washington↗

Optimizing satellite resources for the global assessment and mitigation of volcanic hazards—Suggestions from the USGS Powell Center Volcano Remote Sensing Working Group

A significant number of the world’s approximately 1,400 subaerial volcanoes with Holocene eruptions are unmonitored by ground-based sensors yet constitute a potential hazard to nearby residents and infrastructure, as well as air travel and global commerce. Data from an international constellation of more than 60 current satellite instruments provide a cost-effective means of tracking activity and potentially forecasting hazards at volcanoes around the world. These data span the electromagnetic spectrum: ultraviolet, optical, infrared, and microwave (synthetic aperture radar). They can measure volcanic thermal and gas emissions, ground displacement, and surface and topographic change, providing information that addresses one of the grand challenges in volcanology—to overcome our incomplete understanding of the relation between volcanic unrest and eruption, which is currently based on only a few well-studied volcanoes. Although the potential of volcano remote sensing has been recognized for decades, there are many hurdles to clear before remote sensing data can be used fully by all volcano observatories. These include: (1) the limited temporal and spatial coverage of active volcanoes by satellites and the delayed distribution of those data; (2) the lack of background data acquired at all volcanoes; and (3) limited access to, and utilization of, remote sensing data in some areas owing to a lack of expertise, licensing, user-friendly formats, data access portals, or computational infrastructure. While remote sensing data will never replace ground-based monitoring, a joint observation strategy provides a powerful means of assessing volcanic activity before, during, and after hazardous eruptions, especially given the unique spatial, temporal, and spectral perspective provided by remote measurements. A coordinated international remote sensing observation strategy for volcanoes—similar to one used by the cryosphere community—along with a volcano space task group to maximize the utility of satellite data for volcano monitoring would be highly beneficial. Such a vision could facilitate (1) global coordination of satellite observations (as done for polar regions) for background monitoring and eruption response, (2) open data that can be rapidly distributed during crises, (3) communication tools and forums for discussion of satellite data, (4) integrated ground and satellite databases of unrest, and (5) global capacity building.

Scientific Investigations Report↗

Rangeland Condition Monitoring Assessment and Projection, 1985–2021

The Rangeland Condition Monitoring Assessment and Projection (RCMAP) project quantifies the percentage cover of rangeland components across the western United States using Landsat imagery from 1985 to 2021. The RCMAP product suite consists of nine fractional components: annual herbaceous, bare ground, herbaceous, litter, nonsagebrush shrub, perennial herbaceous, sagebrush, shrub, and tree, in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, we have trained time-series predictions directly from 331 high-resolution sites collected from 2013 to 2018 and additional field data; for example, Bureau of Land Management Assessment, Inventory, and Monitoring instead of using the 2016 “base” map as an intermediary. This removes one level of model error and allows the direct association of high-resolution derived training data to the corresponding year of Landsat imagery. Neural network models have replaced Cubist models as our classifier. Continuous Change Detection and Classification synthetic Landsat images were obtained for six monthly periods for each region and were added as predictors. These data enhance the phenologic detail of imagery, improving discrimination among components. Postprocessing has been improved with updated fire recovery equations stratified by ecosystem resistance and resilience classes. Additionally, postprocessing has been enhanced through a revised noise detection model, based on third order polynomial models for each component and each pixel. These data can be used to answer critical questions regarding the effect of climate change and the suitability of management practices. Component products can be downloaded from the Multi-Resolution Land Characteristics Consortium website at https://www.mrlc.gov/data .

western United States↗

Potential for shoreline changes due to sea-level rise along the U.S. mid-Atlantic region

Sea-level rise over the next century is expected to contribute significantly to physical changes along open-ocean shorelines. Predicting the form and magnitude of coastal changes is important for understanding the impacts to humans and the environment. Presently, the ability to predict coastal changes is limited by the scientific understanding of the many variables and processes involved in coastal change, and the lack of consensus regarding the validity of existing conceptual, analytical, or numerical models. In order to assess potential future coastal changes in the mid-Atlantic U.S. for the U.S. Climate Change Science Program (CCSP), a workshop was convened by the U.S. Geological Survey. Assessments of future coastal change were made by a committee of coastal scientists with extensive professional experience in the mid-Atlantic region. Thirteen scientists convened for a two-day meeting to exchange information and develop a consensus opinion on potential future coastal changes for the mid-Atlantic coast in response to sea-level rise. Using criteria defined in past work, the mid-Atlantic coast was divided into four geomorphic compartments: spits, headlands, wave-dominated barriers, and mixed-energy barriers. A range of potential coastal responses was identified for each compartment based on four sea-level rise scenarios. The four scenarios were based on the assumptions that: a) the long-term sea-level rise rate observed over the 20th century would persist over the 21st century, b) the 20th century rate would increase by 2 mm/yr, c) the 20th century rate would increase by 7 mm/yr, or d) sea-level would rise by 2 m over the next few hundred years. Potential responses to these sea-level rise scenarios depend on the landforms that occur within a region and include increased likelihood for erosion and shoreline retreat for all coastal types, increased likelihood for erosion, overwash and inlet breaching for barrier islands, as well as the possibility of a threshold state (e.g., dramatic change in barrier evolution, such as segmentation or disintegration) for some barrier island systems. The likelihood of the potential coastal responses is expressed using standard terminology employed in climate change assessments (e.g., as used by the Intergovernmental Panel on Climate Change and CCSP). This assessment was based on the coastal geomorphology in its present condition and does not consider any coastal protection that might be undertaken in the future. The committee recognized that a variety of erosion mitigation measures have been implemented along developed portions of the coast and these are very likely to be applied in the future. It was also acknowledged that economics, political will, and other factors can drive decisions to implement these measures, and that such decisions cannot be predicted with confidence. The results of this assessment are depicted graphically on maps of the study area.

Mid-Atlantic Coast↗

Outcrop descriptions and fossils from the Upper Cretaceous Frontier Formation, Wind River Basin and adjacent areas, Wyoming: Chapter 11 in Petroleum systems and geologic assessment of oil and gas resources in the Wind River Basin Province, Wyoming

The Wind River Basin of central Wyoming trends west-northwest from near the community of Alcova to near the town of Dubois (fig. 1). On the perimeter of the basin, outcrops of the Frontier Formation were examined and described during the years 1972-1975. Invertebrate fossils were collected from those outcrops during the years 1972-1996, in places with the assistance of other earth scientists (see Acknowledgments). The Frontier Formation in the Wind River Basin, ranging in thickness from 650 to 1,000 ft thick, consists mainly of sandstone, siltstone, shale, and bentonite of early Late Cretaceous age. The Frontier conformably overlies the Mowry Shale and is conformably overlain by the Cody Shale. A basal unit of the Cody, a sequence of marine noncalcareous shale, is named the Sage Breaks Member. The Frontier consists of two or three members, separated by disconformities; in ascending order, the Belle Fourche, Emigrant Gap, and Wall Creek. At several localities, the Emigrant Gap Member is missing. The formation was deposited mainly in marine environments, although nonmarine beds are conspicuous in the western part of the basin. Strata of the Frontier record a succession of marine regressions and transgressions. Molluscan fossils from the marine beds were identified and related to the chronostratigraphic chart shown in figure 2. The absolute ages on the chart were determined and supplied by J.D. Obradovich (Cobban and others, 2006). In this region, the Belle Fourche is of Cenomanian age, the Emigrant Gap is of early middle Turonian age, and the Wall Creek is of late Turonian and early Coniacian ages. The main purpose of this report is to present biostratigraphic information from studies of the Frontier Formation in the Wind River Basin that could be useful for future stratigraphic investigations of the formation throughout Wyoming. Locations of outcrop sections and associated fossil collections are depicted on accompanying maps and aerial photographs. Graphic descriptions of strata in the outcrops and identifications of fossils from nearby localities also are presented. Those fossils named on the graphic sections commonly have the most restricted time-spans. Fossils collected near the outcrops studied are not always named on the enclosed graphic sections because (1) the specimens are less useful for dating the enclosing beds, (2) the specimens are duplicates, or (3) the specimens could not be related to specific strata in the sections. The names, locations, and members of the outcrop sections and the approximate ages of the constituent strata are summarized in table 1. The index maps used to show locations of outcrop sections and fossil collections are from scanned versions of U.S. Geological Survey topographic maps of various scales and were obtained from TerraServer®. The portion of each map used depended on the areal distribution of the localities involved. The named quadrangles used for locality descriptions, however, all refer to 7½-minute, 1:24,000-scale quadrangles (for example, “Alcova”). The aerial photographs also are from TerraServer®; http://www.terraserver.com/.

Wyoming↗

The Environmental Monitoring and Assessment Program (EMAP)-West: Summary of activities and accomplishments in South Dakota, 2000-2004

The Environmental Monitoring and Assessment Program (EMAP)-West was initiated in South Dakota in 2000 by the U.S. Environmental Protection Agency (USEPA). The two primary objectives of the surface waters component of EMAP-West were to (1) develop the monitoring tools (biological indicators, stream survey design, estimates of reference condition) necessary to produce unbiased estimates of the ecological condition of surface waters across a large geographic area of the West; and (2) demonstrate the effectiveness of those tools in a large-scale assessment. Although not specifically defined as an objective, data collected during EMAP-West also will help to establish a baseline for comparisons with data obtained from future monitoring efforts and could document changing biological conditions resulting from changing land-use or land-management practices associated with regulatory or restorative efforts. EMAP-West is a partnership between USEPA, States, Tribes, and other inter­ested parties in USEPA Regions 8, 9, and 10. In South Dakota, the principle EMAP-West cooperators include the USEPA, South Dakota Department of Game, Fish and Parks (GF&P), and the U.S. Geological Survey (USGS). Other agencies such as the Natural Resource Conservation ­Service, the South Dakota Department of Environment and Natural Resources (SDDENR), State Conservation Dis­tricts, and various Tribal departments also have provided valuable expertise and assistance. This fact sheet summarizes the activities and accomplishments associated with EMAP-West in South Dakota during 2000–2004. Efforts were focused on perennial streams that usually can be waded. Large rivers also were assessed during EMAP-West under the auspices of USEPA using boats and similar techniques, but are not included in the activities discussed here. Data-collection activities for wadeable streams were conducted under the auspices of USEPA in South Dakota during 2000 and by the USGS during 2001–2004. A more detailed description of EMAP-West activities and assessments in South Dakota is available in Heakin and others ( in press ).

South Dakota↗

Initial Everglades Depth Estimation Network (EDEN) digital elevation model research and development

The Everglades Depth Estimation Network (EDEN) offers a consistent and documented dataset that can be used to guide large-scale field operations, to integrate hydrologic and ecological responses, and to support biological and ecological assessments that measure ecosystem responses to the Comprehensive Everglades Restoration Plan (Telis, 2006). To produce historic and near-real time maps of water depths, the EDEN requires a system-wide digital elevation model (DEM) of the ground surface. Accurate Everglades wetland ground surface elevation data were non-existent before the U.S. Geological Survey (USGS) undertook the collection of highly accurate surface elevations at the regional scale. These form the foundation for EDEN DEM development. This development process is iterative as additional high accuracy elevation data (HAED) are collected, water surfacing algorithms improve, and additional ground-based ancillary data become available. Models are tested using withheld HAED and independently measured water depth data, and by using DEM data in EDEN adaptive management applications. Here the collection of HAED is briefly described before the approach to DEM development and the current EDEN DEM are detailed. Finally future research directions for continued model development, testing, and refinement are provided.

Florida↗

Evaluation of alternative groundwater-management strategies for the Bureau of Reclamation Klamath Project, Oregon and California

The water resources of the upper Klamath Basin, in southern Oregon and northern California, are managed to achieve various complex and interconnected purposes. Since 2001, irrigators in the Bureau of Reclamation Klamath Irrigation Project (Project) have been required to limit surface-water diversions to protect habitat for endangered freshwater and anadromous fishes. The reductions in irrigation diversions have led to an increased demand for groundwater by Project irrigators, particularly in drought years. The potential effects of sustained pumping on groundwater and surface-water resources have caused concern among Federal and state agencies, Indian tribes, wildlife groups, and groundwater users. To aid in the development of a viable groundwater-management strategy for the Project, the U.S. Geological Survey, in collaboration with the Klamath Water and Power Agency and the Oregon Water Resources Department, developed a groundwater-management model that links groundwater simulation with techniques of constrained optimization. The overall goal of the groundwater-management model is to determine the patterns of groundwater pumping that, to the extent possible, meet the supplemental groundwater demands of the Project. To ensure that groundwater development does not adversely affect groundwater and surface-water resources, the groundwater-management model includes constraints to (1) limit the effects of groundwater withdrawal on groundwater discharge to streams and lakes that support critical habitat for fish listed under the Endangered Species Act, (2) ensure that drawdowns do not exceed limits allowed by Oregon water law, and (3) ensure that groundwater withdrawal does not adversely affect agricultural drain flows that supply a substantial portion of water for irrigators and wildlife refuges in downslope areas of the Project. Groundwater-management alternatives were tested and designed within the framework of the Klamath Basin Restoration Agreement (currently [2013] awaiting authorizing Federal legislation), which would establish a permanent limit on the amount of surface water that can be diverted annually to the Project. Groundwater-management scenarios were evaluated for the period 1970•2004; supplemental groundwater demand by the Project was estimated as the part of irrigation demand that would not have been satisfied by the surface-water diversion allowed under the Klamath Basin Restoration Agreement. Over the 35-year management period, 22 years have supplemental groundwater demand, which ranges from a few thousand acre-feet (acre-ft) to about 100,000 acre-ft in the driest years. The results of the groundwater-management model indicate that supplemental groundwater pumping by the Project can be managed to avoid adverse effects to groundwater discharge that supports critical aquatic habitat. The existing configuration of wells in the Project would be able to meet groundwater-pumping goals in 14 of the 22 years with supplemental groundwater demand; however, substantial irrigation shortages can be expected during drought periods when the demand for supplemental groundwater is highest. The maximum irrigation-season withdrawal calculated by the groundwater-management model is about 60,000 acre-ft, the average withdrawal in drought years is about 54,000 acre-ft, and the amount of unmet groundwater demand reaches a maximum of about 45,000 acre-ft. A comparison of optimized groundwater withdrawals by geographic region shows that the highest annual withdrawals are associated with wells in the Tule Lake and Klamath Valley regions of the Project. The patterns of groundwater withdrawal also show that a substantial amount of the available pumping capacity is unused due to the restrictions imposed by drawdown constraints. Subsequent model applications were used to evaluate the sensitivity of optimization results to various factors. A sensitivity analysis quantified the changes in optimized groundwater withdrawals that result from changes in drawdown-constraint limits. The analysis showed the potential for substantial increases in withdrawals of groundwater with less restrictive drawdown limits at drawdown-control sites in the California part of the model. Systematic variation of the drains-constraint limit yielded a trade-off curve between optimized groundwater withdrawals and the allowable reduction in groundwater discharge to the Project drain system. Additional model applications were used to assess the value of increasing the pumping capacity of the network of wells serving the Project, and the relation between reduced off-Project groundwater pumping and increased pumping by Project irrigators.

California;Oregon↗

Water-quality assessment of the Delmarva Peninsula, Delaware, Maryland, and Virginia: Results of investigations, 1987-91

A regional ground-water-quality assessment of the Delmarva Peninsula was conducted as a pilot study for the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. The study focused on the surficial aquifer and used both existing data and new data collected between 1988 and 1991. The new water samples were analyzed for major ions, nutrients, radon, volatile organic compounds, and a suite of herbicides and insecticides commonly used on corn, soybeans, and small grains. Samples also were collected from wells completed in deeper, confined aquifers and from selected streams, and analyzed for most of these constituents. The study employed a multi-scale network design. Regional networks were chosen to provide broad geographic coverage of the study area and to ensure that the major hydrogeologic settings of the surficial aquifer were adequately represented. Both the existing data and the data from samples collected during the study showed that agricultural activities had affected the quality of water in the surficial aquifer over most of the Peninsula.

Delaware, Maryland, Virginia↗

North Atlantic right whale (Eubalaena glacialis) scenario planning summary report

Scenario planning provides a structured framework that can be used in strategic planning to help manage risk and prioritize actions (Schwartz 1996; Peterson et al. 2003). By providing a mechanism to communicate about complex situations, scenario planning encourages “out-of-the-box” thinking to help groups assess the impacts of plausible future scenarios on a target or resource. The outcomes from scenario planning can be used to improve management decisions, highlight data gaps, and/or identify future science priorities (Star et al. 2015; Borggaard et al. 2019). The application of scenario planning by resource management organizations (e.g., Borggaard et al. 2019; Runyon et al. 2020; Star et al. 2015) and the urgency surrounding the recovery of the critically endangered North Atlantic right whale (Eubalaena glacialis), led to a 2018 NOAA Fisheries scenario planning initiative for the species. In addition to complementing the many management and conservation efforts already underway, this initiative was designed to address the uncertainties around future anthropogenic and environmental changes and how these uncertainties may impact species recovery. We used a scenario planning framework to explore plausible future conditions for North Atlantic right whales and to develop possible options to address those conditions and improve recovery. Specific objectives were to: 1) better understand the challenges of right whale management in a changing climate; 2) identify potential research activities and recovery needs across the species’ range; 3) increase coordination and collaboration related to recovery efforts; and 4) explore how scenario planning can be used to support decisions. Using projected changes in ocean conditions coupled with anthropogenic stressors, we built four plausible future scenarios for right whales. These scenarios helped identify priority research and management actions that NOAA Fisheries and our partners can undertake to improve right whale recovery. We identified priority actions related to science, management, and partnerships including, but not limited to, 1) research on shifting spatial and temporal distributions of right whales and prey in a changing climate; 2) development of technology to further reduce impacts from human activities; 3) continuation of ongoing management efforts related to vessel traffic and fishing; and 4) continued maintenance of existing and development of new partnerships (e.g., industry engagement in problem solving). This scenario planning exercise helped prioritize North Atlantic right whale management and science needs in light of changing ocean conditions and anthropogenic impacts. It can also serve as a reference for how NOAA Fisheries and its partners can better prepare for multiple plausible futures while complementing other on-going initiatives. Priorities identified here can be considered in conjunction with implementation and monitoring actions such as with the Atlantic Large Whale Take Reduction Team (ALWTRT) and/or regional Right Whale U.S. Implementation Teams. The framework can also be repeated and improved upon as additional information becomes available to support future exercises.

Technical Memorandum↗

An assessment of uranium in groundwater in the Grand Canyon region

The Grand Canyon region in northern Arizona is a home or sacred place of origin for many Native Americans and is visited by over 6 million tourists each year. Most communities in the area depend upon groundwater for all water uses. Some of the highest-grade uranium ore in the United States also is found in the Grand Canyon region. A withdrawal of over 1 million acres of Federal land in the Grand Canyon region from new uranium mining activities for 20 years was instituted in 2012, owing in part to a lack of scientific data on potential effects from uranium mining on water resources in the area. The USGS collects groundwater chemistry samples in the Grand Canyon region to understand the current state of groundwater quality, to monitor for changes in groundwater quality that may be the result of mining activities, and to identify "hot spots" with elevated metal concentrations and investigate the causes. This manuscript presents results for the assessment of uranium in groundwater in the Grand Canyon region. Analytical results for uranium in groundwater in the Grand Canyon region were available for 573 samples collected from 180 spring sites and 26 wells from September 1, 1981 to October 7, 2020. Samples were collected from springs issuing from stratigraphic units above, within, and below the Permian strata that hosts uranium ore in breccia pipes in the area. Maximum uranium concentrations at groundwater sites in the region ranged from less than 1 µg/L at 23 sites (11%) to 100 µg/L or more at 4 sites (2%). Of the 206 groundwater sites sampled, 195 sites (95%) had maximum observed uranium concentrations less than the USEPA Maximum Contaminant Level of 30 µg/L and 177 sites (86%) had uranium concentrations less than the 15 µg/L Canadian benchmark for protection of aquatic life in freshwater. The establishment of baseline groundwater quality is an important first step in monitoring for change in water chemistry throughout mining lifecycles and beyond to ensure the health of these critical groundwater resources.

Arizona↗

Spatial, road geometric, and biotic factors associated with Barn Owl mortality along an interstate highway

Highway programs typically focus on reducing vehicle collisions with large mammals because of economic or safety reasons while overlooking the millions of birds that die annually from traffic. We studied wildlife‐vehicle collisions along an interstate highway in southern Idaho, USA, with among the highest reported rates of American Barn Owl Tyto furcata road mortality. Carcass data from systematic and ad hoc surveys conducted in 2004–2006 and 2013–2015 were used to explore the extent to which spatial, road geometric, and biotic factors explained Barn Owl‐vehicle collisions. Barn Owls outnumbered all other identified vertebrate species of roadkill and represented > 25% of individuals and 73.6% of road‐killed birds. At a 1‐km highway segment scale, the number of dead Barn Owls decreased with increasing numbers of human structures, cumulative length of secondary roads near the highway, and width of the highway median. Number of dead Barn Owls increased with higher commercial average annual daily traffic (CAADT), small mammal abundance index, and with grass rather than shrubs in the roadside verge. The small mammal abundance index was also greater in roadsides with grass versus mixed shrubs, suggesting that Barn Owls may be attracted to grassy portions of the highway with more abundant small mammals for hunting prey. When assessed at a 3‐km highway segment scale, the number of dead Barn Owls again increased with higher CAADT as well as with greater numbers of dairy farms. At a 5‐km scale, number of dead Barn Owls increased with greater percentage of cropland near the highway. While human conversion of the environment from natural shrub‐steppe to irrigated agriculture in this region of Idaho has likely enhanced habitat for Barns Owls, it simultaneously has increased risk for owl‐vehicle collisions where an interstate highway traverses the altered landscape. We review some approaches for highway mitigation and suggest that reducing wildlife‐vehicle collisions involving Barn Owls may contribute to the persistence of this species.

Idaho↗

Notes on the availability of mid-Atlantic multichannel seismic reflection profiles 11 and 12-A, -B, -C, and -D

Available are two multichannel profiles collected by Digicon Geophysical Corporation in 1975 using a 48-channel streamer (3600 m long). and a 27.9 cu. liter air gun array. They were processed in Denver on the Phoenix "I" by William C. Patterson. The processing included demultiplexing and resampling, geometry and common-depth-point definition, velocity analysis, noise muting, band-pass filtering, time-variant filtering, time-variant deconvolution, and automatic gain control (AGC) scaling, prior to the final profile playout. The release includes parts of two lines off the mid-atlantic continental margin (see map) over the Baltimore Canyon trough. These profiles were collected as part of a regional grid over the offshore Atlantic sedimentary basins, as a part of a continuing program to assess the resource potential using non-proprietary data Line 11 is a cross shelf profile (233 ken long) taken across the shelf, slope and upper rise off Virginia (southern Baltimore Canyon trough). Line 12 (shotpoint 1Ol- 6011, parts A, 8, C and D) is an along-the-shelf profiler and stretches from the Cape Hatteras IPOD line to line 2, at the northern part of the Baltimore Canyon trough), a distance of 591 km. These profiles may be viewed at the U.S. Geological Survey, Atlantic Gulf of Mexico, Office of Marine Geology, Quissett campus, Building B, Woods Hole, Massachusetts 02543, and at the U.S. Geological Survey, Branch of Oil and Gas Resources, Denver Federal Center, Building 25, Denver. Colorado 80225. Copies of the profiles can be purchased from the Nations Geophysical and Solar-Terrestrial Data Center, Environmental Data Service- NOAA, Code D621 Boulder, Colorado 80303.

Open-File Report↗

Early Pliocene (Zanclean) sea surface temperature for PlioMIP3

Paleoclimate researchers have been comparing Pliocene environmental data to paleoclimate model results since the 1980s. The Pliocene Model Intercomparison Project (PlioMIP) began in 2008 with a focus on the Late Pliocene. Here we assess the availability and utility of sea surface temperature (SST) data for verification of Pliocene Model Intercomparison Project (PlioMIP3) Early Pliocene (Zanclean) experiments. We analyze published data in terms of quantity and spatial distribution. Only SST estimates derived using alkenone paleo thermometry are reported, and all estimates are based upon the same temperature calibration. Sea surface temperature data are selected from within three distinct time intervals: The early Zanclean 5.3 Ma – 4.2 Ma time slab, and two time slices within the early Zanclean, chosen by PlioMIP3 at 4.870 Ma and 4.474 Ma. Results show the early Zanclean time slab contains 2055 individual estimates. Approximately ∼ 80% of these estimates come from Sites 609, 642, 846, 847, 882, 907, and 1146. There are 17 sites with a total of 42 estimates within the 4.474 Ma ±10 kyr time slice, and 15 sites with a total of 47 data points within the 4.870 Ma ±10 kyr interval. The sparse spatial and temporal distribution of Zanclean data, relative to the data available for the mid Piacenzian, makes point-by-point data model comparison suspect. We suggest interpreting model output against lower resolution long term trends in proxy data, and comparison of models through temperature gradients, may be the most useful application of currently available data. Integrating Zanclean age coastal plain sequences within data model comparison schemes, for increased understanding of regional climate impacts, also holds great potential.

Global and Planetary Change↗

Evidence that life history characteristics of wild birds influence infection rates and exposure to influenza A viruses

We report on life history characteristics, temporal, and age-related effects influencing the frequency of occurrence of avian influenza (AI) viruses in four species of migratory geese breeding on the Yukon-Kuskokwim Delta, Alaska. Emperor geese ( Chen canagica ), cackling geese ( Branta hutchinsii ), greater white-fronted geese ( Anser albifrons ), and black brant ( Branta bernicla ), were all tested for active infection of AI viruses upon arrival in early May, during nesting in June, and while molting in July and August, 2006–2010 ( n = 14,323). Additionally, prior exposure to AI viruses was assessed via prevalence of antibodies from sera samples collected during late summer in 2009 and 2010. Results suggest that geese are uncommonly infected by low pathogenic AI viruses while in Alaska. The percent of birds actively shedding AI viruses varied annually, and was highest in 2006 and 2010 (1–3%) and lowest in 2007, 2008, and 2009 (<0.70%). Contrary to findings in ducks, the highest incidence of infected birds was in late spring when birds first arrived from staging and wintering areas. Despite low prevalence, most geese were previously exposed to AI viruses, as indicated by high levels of seroprevalence during late summer (47%–96% across species; n = 541 ). Seroprevalence was >95% for emperor geese, a species that spends part of its life cycle in Asia and is endemic to Alaska and the Bering Sea region, compared to 40–60% for the other three species, whose entire life cycles are within the western hemisphere. Birds <45 days of age showed little past exposure to AI viruses, although antibodies were detected in samples from 5-week old birds in 2009. Seroprevalence of known age black brant revealed that no birds <4 years old had seroconverted, compared to 49% of birds ≥4 years of age.

Alaska↗

Section 5: Remote sensing of vegetation in the riparian corridor of the Colorado River’s delta 2013-2018

This remote sensing section is based on Nagler et al. (in preparation for the journal Hydrological Processes) and is a summary of the USGS preliminary findings to date. This report documents the changes in green foliage density (greenness) as measured by satellite vegetation index (VI) data and corresponding evapotranspiration (ET) in the riparian corridor of the Colorado River delta associated with the Minutes 319 and 323 environmental water deliveries using time-series data from 2013 through 2018. The report focuses on what happened only within the riparian corridor’s seven reaches since the 2014 flows, and despite being a continuation of measuring greenness and ET after the 2017 end of Minute 319, this study continued the tracking of these two variables, greenness and ET, in these original riparian corridor focal areas. Two spatial scales are used here: (1) Landsat satellite imagery at 30 m pixels and (2) the EOS-1 satellite sensor the Moderate Resolution Imaging Spectrometer (MODIS) with a resolution of 250 m pixels. The focal period includes 2013 (prepulse flow) and the years 2014-2018, with a focus on imagery collected from the Summer growing seasons 2014 through 2018 (one-year, pre-pulse and several post-pulse years, respectively). This report re-creates the 2013-2017 Landsat-based results from Jarchow et al. (2017a, b) by using the same region of interest (ROI). The report now provides revised and re-created results using all new imagery acquisition and processing techniques, as well as extraction code, created by the Vegetation Index and Phenology (VIP) Lab of the Biosystems Engineering Department of the University of Arizona (UofA). In 2018, methods employed by the VIP lab (and not ArcGIS) were used. ArcGIS was only used in the newly processed data to display the final difference maps. The entire spatial tile data from NASA was downloaded and processed at the VIP Lab using satellite imagery at two resolutions: 250 m MODIS and 30 m Landsat using three sensors, Landsat 5, Landsat 7 ETM+ and Landsat 8 Operational Land Imager (OLI), with added scenes for each year based on new clear atmosphere requirements. The VIP lab clipped the river boundary and seven riparian reaches from the previously existing ROI used in Jarchow et al. (2017 a, b) for the analyses done under Minute 319. The NASA image datasets for this riparian corridor ROI in seven reaches were re-processed to produce additional vegetation index (VI) information for years 2013 to 2018 for this report. At the same time, the report acquired and processed imagery from 2000- 2018 (data outside the scope of this report and data not shown here). The additional VIs (NDVI, scaled NDVI, EVI, EVI2) were analyzed so that new assessments of greenness and ET could be produced from the imagery datasets following methods in Nagler et al. (2013). These VI choices were based on previous performance comparisons between biophysical ground-based data and radiometric satellite-based data collected from this riparian ecosystem (Nagler et al., 2001) as well as performance related to ET estimation (Nagler et al., 2005a, b) and current advancements in VIs such as EVI2.

Colorado River Delta↗

Transcriptome signatures of wastewater effluent exposure in larval zebrafish vary with seasonal mixture composition in an effluent-dominated stream

Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic and terrestrial organisms but also continually expose them to complex mixtures of pharmaceuticals that can potentially impair growth, behavior, and reproduction. Currently, few biomarkers are available that relate to pharmaceutical-specific mechanisms of action. In the experiment reported in this paper, zebrafish ( Danio rerio ) embryos at two developmental stages were exposed to water samples from three sampling sites (0.1 km upstream of the outfall, at the effluent outfall, and 0.1 km below the outfall) during base-flow conditions from two months (January and May) of a temperate-region effluent-dominated stream containing a complex mixture of pharmaceuticals and other contaminants of emerging concern. RNA-sequencing identified potential biological impacts and biomarkers of WWTP effluent exposure that extend past traditional markers of endocrine disruption. Transcriptomics revealed changes to a wide range of biological functions and pathways including cardiac, neurological, visual, metabolic, and signaling pathways. These transcriptomic changes varied by developmental stage and displayed sensitivity to variable chemical composition and concentration of effluent, thus indicating a need for stage-specific biomarkers. Some transcripts are known to be associated with genes related to pharmaceuticals that were present in the collected samples. Although traditional biomarkers of endocrine disruption were not enriched in either month, a high estrogenicity signal was detected upstream in May and implicates the presence of unidentified chemical inputs not captured by the targeted chemical analysis. This work reveals associations between bioeffects of exposure, stage of development, and the composition of chemical mixtures in effluent-dominated surface water. The work underscores the importance of measuring effects beyond the endocrine system when assessing the impact of bioactive chemicals in WWTP effluent and identifies a need for non-targeted chemical analysis when bioeffects are not explained by the targeted analysis.

Iowa↗

Wyoming Basin Rapid Ecoregional Assessment

The overall goal of the Wyoming Basin Rapid Ecoregional Assessment (REA) is to provide information that supports regional planning and analysis for the management of ecological resources. The REA provides an assessment of baseline ecological conditions, an evaluation of current risks from drivers of ecosystem change (including energy development, fire, and invasive species), and a predictive capacity for evaluating future risks (including climate change). Additionally, the REA may be used for identifying priority areas for conservation or restoration and for assessing cumulative effects of multiple land uses. The Wyoming Basin REA will address Management Questions developed by the Bureau of Land Management and other agency partners for 8 major biomes and 19 species or species assemblages. The maps developed for addressing Management Questions will be integrated into overall maps of landscape-level ecological values and risks. The maps can be used to address the goals of the REA at a number of levels: for individual species, species assemblages, aquatic and terrestrial systems, and for the entire ecoregion. This allows flexibility in how the products of the REA are compiled to inform planning and management actions across a broad range of spatial scales.

Colorado;Idaho;Montana;Utah;Wyoming↗