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At least 1,441 records · Page 80Linked to original sources

Brief oil exposure reduces fitness in wild Gulf of Mexico mahi-mahi (Coryphaena hippurus)

The Deepwater Horizon (DWH) disaster released 3.19 million barrels of crude oil into the Gulf of Mexico (GOM) in 2010, overlapping the habitat of pelagic fish populations. Using mahi-mahi ( Coryphaena hippurus )─a highly migratory marine teleost present in the GOM during the spill─as a model species, laboratory experiments demonstrate injuries to physiology and behavior following oil exposure. However, more than a decade postspill, impacts on wild populations remain unknown. To address this gap, we exposed wild mahi-mahi to crude oil or control conditions onboard a research vessel, collected fin clip samples, and tagged them with electronic tags prior to release into the GOM. We demonstrate profound effects on survival and reproduction in the wild. In addition to significant changes in gene expression profiles and predation mortality, we documented altered acceleration and habitat use in the first 8 days oil-exposed individuals were at liberty as well as a cessation of apparent spawning activity for at least 37 days. These data reveal that even a brief and low-dose exposure to crude oil impairs fitness in wild mahi-mahi. These findings offer new perspectives on the lasting impacts of the DWH blowout and provide insight about the impacts of future deep-sea oil spills.

Environmental Science and Technology↗

Seasonal variations of carbon dioxide concentrations in stony, coarse-textured desert soils of southern Nevada, USA

Knowledge of carbon dioxide concentration in desert soils is required in theoretical models of the development of pedogenic and ground-water calcium carbonate. Most studies have concentrated on medium- to fine-textured soils in temperate to humid environments. Very little data exist for CO 2 concentrations in stony, coarse-textured deposits such as those making up alluvial fans and fluvial terraces. The purpose of this study was to obtain CO 2 concentration data in stony, coarse-textured, uncultivated soils in a desert environment. Soil gas samples were collected from two sites—Yucca Wash and Rock Valley—at the Nevada Test Site in southern Nevada between June 1985 and June 1986 to determine soil CO 2 concentrations and their seasonal and depth variations in the soil profile. Soil CO 2 concentrations ranged from 0.03 volume percent in winter and summer to 0.25 volume percent in spring. During the summer, fall, and winter, CO 2 concentrations were close to atmospheric levels and varied randomly with depth. In spring, CO 2 varied with root density, highest concentrations occurring between 40 and 80 cm of depth. Maximum CO 2 values decrease and occur at progressively deeper levels toward the end of spring. Biological activity appears to be limited throughout the year because of the arid climate. During the winter and spring, soil CO 2 appears to be more dependent on temperature than moisture, whereas in the summer and fall it appears to be dependent on moisture. Soil gas samples were also collected during the spring from three sites in the Kyle Canyon area in southern Nevada to determine the variation of soil CO 2 levels with changes in elevation and vegetation. Soil CO 2 values increased from 0.04 to 0.24 volume percent with increasing elevation.

Nevada↗

A characterization of the deep-sea coral and sponge community along the Oregon Coast using a remotely operated vehicle on the EXPRESS 2022 expedition

Deep-sea coral and sponge (DSCS) communities serve as essential fish habitat (EFH) by providing shelter and nursery habitat, increasing diversity, and increasing prey availability (Freese and Wing, 2003; Bright, 2007; Baillon et al., 2012; Henderson et al., 2020). Off the U.S. West Coast, threats to these long-lived, fragile organisms from bottom contact fishing gear, potential offshore renewable energy development, and ocean warming and acidification have been the subject of recent research (Gomez et al., 2018; Salgado et al., 2018; Yoklavich, et al., 2018; Gugliotti et al., 2019). Other DSCS studies have reported new species (Yoklavich and Love, 2005), analyzed species distribution and abundance (Tissot et al., 2006, Watters et al., 2022), developed predictive distribution models (Huff et al., 2013; Rooper et al., 2017; Kreidler, 2020), and discovered medicinal uses for corals and sponges (Essack et al., 2011; Shrestha et al., 2018). Due to the vast area of unexplored seafloor within the territorial waters and the U.S. exclusive economic zone (EEZ; 12-200 nautical miles off the coast) and the technological requirements and expense of deep-sea research, there is still much to learn about the distributions and biology of DSCS. This information is critical to resource managers for effective conservation and management of DSCS habitats. In order to minimize the adverse impacts of fishing on EFH, the Pacific Fishery Management Council (PFMC) and National Marine Fisheries Service (NMFS) designated several seafloor habitat areas as EFH conservation areas (EFHCA), first in 2006 (as part of Amendment 19 to the Pacific coast groundfish fishery management plan) and then again in 2020 (as part of Amendment 28). These areas are closed to bottom trawl fishing at a minimum, and in some cases to all bottom contact fishing gears. In addition to protections afforded by EFH-related regulations, the National Marine Sanctuary Program prohibits certain non-fishing activities within areas designated as national marine sanctuaries, such as oil and gas exploration or extraction, cable laying, and other forms of seabed alteration or construction that disturb benthic communities. NOAA’s Deep-Sea Coral and Research Technology Program (DSCRTP) began a 4-yr funding initiative for the U.S. West Coast in 2017. The goals of the West Coast Deep-Sea Coral Initiative (WCDSCI) were to: 1) gather baseline information on areas subject to fishing regulation changes prior to the implementation of Amendment 28; 2) improve our understanding of known DSCS bycatch “hot spots”; and 3) explore and assess DSCS resources within NOAA National Marine Sanctuaries with emphasis on areas of sanctuary resource protection and management concerns. As part of the WCDSCU, an 11-day expedition (3 Sep – 13 Sep 2022) was launched from the NOAA Ship Bell M. Shimada, beginning and ending in Newport, OR. The science team assembled for this cruise were members of the EXpanding Pacific Research and Exploration of Submerged Systems (EXPRESS) campaign, which brings together researchers from federal and nonfederal institutions to collaborate on scientific expeditions targeting the deepwater areas off California, Oregon, and Washington. EXPRESS supports researchers leveraging funding, resources, personnel, and expertise to accomplish more science than would have been possible by a single entity alone. The 2022 expedition included research partners from National Marine Fisheries Service (NMFS) Southwest Fisheries Science Center (SWFSC) and Northwest Fisheries Science Center (NWFSC), Bureau of Ocean Energy Management (BOEM), U.S. Geological Survey (USGS), Pacific Fisheries Management Council Habitat Committee, and Woods Hole Oceanographic Institution.

Report↗

Transport of horseshoe crab eggs by waves and swash on an estuarine beach: Implications for foraging shorebirds

The abundance of horseshoe crab eggs in the swash zone and remaining on the beach after tide levels fall was evaluated to identify how numbers of eggs available to shorebirds differ with fluctuations in spawning numbers of horseshoe crabs, wave energies and beach elevation changes. Field data were gathered 1-6 June 2004 at Slaughter Beach on the west side of Delaware Bay, USA. Counts of spawning crabs and process data from a pressure transducer and an anemometer and wind vane were related to number of eggs, embryos and larvae taken at depth and on the surface of the foreshore and in the active swash zone using a streamer trap. Beach elevation changes and depths of sediment activation were used to determine the potential for buried eggs to be exhumed by waves and swash. Mean significant wave heights during high water levels ranged from 0.08 to 0.40 m. Spawning counts were low (50-140 females km-1) when wave heights were low; no spawning occurred when wave heights were high. Vegetative litter (wrack) on the beach provides local traps for eggs, making more eggs available for shorebirds. Accumulation of litter on days when wave energy is low increases the probability that eggs will remain on the surface. High wave energies transport more eggs in the swash, but these eggs are dispersed or buried, and fewer eggs remain on the beach. Peaks in the number of eggs in the swash uprush occur during tidal rise and around time of high tide. The number of eggs in transport decreases during falling tide. Many more eggs move in the active swash zone than are found on the beach after water level falls, increasing the efficiency of bird foraging in the swash. Greater numbers of eggs in the swash during rising tide than falling tide and fewer eggs at lower elevations on the beach, imply that foraging becomes less productive as the tide falls and may help account for the tendency of shorebirds to feed on rising tides rather than on falling or low tides on days when no spawning occurs. ?? 2006 Elsevier Ltd. All rights reserved.

Estuarine, Coastal and Shelf Science↗

Potential toxicity of complex mixtures in surface waters from a nationwide survey of United States streams: Identifying in vitro bioactivities and causative chemicals

While chemical analysis of contaminant mixtures remains an essential component of environmental monitoring, bioactivity-based assessments using in vitro systems increasingly play a role in the detection of biological effects. Historically, in vitro assessments focused on a few biological pathways, e.g., aryl hydrocarbon receptor (AhR) or estrogen receptor (ER) activities. High-throughput screening (HTS) technologies have greatly increased the number of biological targets and processes that can be rapidly assessed. Here we screened extracts of surface waters from nationwide survey of United States (US) streams for bioactivities associated with 69 different endpoints using two multiplexed HTS assays. Bioactivity of extracts from 38streams was evaluated and compared with concentrations of over 700 analytes to identify chemicals contributing to observed effects. Eleven primary biological endpoints were detected. Pregnane X receptor and AhR-mediated activities were the most commonly detected. Measured chemicals did not completely account for AhR and PXR responses. Surface waters with AhR and PXR effects were associated with low intensity, developed land-cover. Likewise, elevated bioactivities frequently associated with wastewater discharges included endocrine related endpoints— ER and glucocorticoid receptor (GR). These results underscore the value of bioassay-based monitoring of environmental mixtures for detecting biological effects that could not be ascertained solely through chemical analyses.

Environmental Science & Technology↗

Habitat use of anadromous and amphidromous sturgeons in North America: A systematic review

Sturgeons are among the most endangered fishes in the world. Identifying habitat use characteristics to inform restoration projects is crucial for recovery. However, small sample sizes, inadequate replication of studies, and limited spatial extents complicate our ability to effectively apply the findings of single studies to endangered species conservation across the larger riverscape. We synthesized information from amphidromous and anadromous sturgeons in North America to identify species-specific knowledge gaps and conduct a quantitative comparison of species–habitat relationships. We provided a qualitative summary of substrate use and synthesized estimates of depth and velocity during spawning and non-spawning activity. Generalized patterns among species were identified, such as spawning in fast water on hard substrate and then using slow water with soft substrate areas when not spawning. We noted species-specific variability during spawning that may be attributed to historical maximum length, egg characteristics, and watershed features. This study provides some of the first estimates of habitat use that can be adapted for many populations. Results can contribute to empirically grounded decision-support tools used to prioritize information needs for recovery.

Canadian Journal of Fisheries and Aquatic Sciences↗

New 40Ar/39Ar isotopic dates from Miocene volcanic rocks in the Lake Mead area and southern Las Vegas Range, Nevada

New 40 Ar/ 39 Ar dates on volcanic rocks interlayered with synextensional Miocene sedimentary rocks in the western Lake Mead area and southern end of the Las Vegas Range provide tight constraints on magmatism, basin formation, and extensional deformation in the Basin and Range province of southern Nevada. Vertical axis rotations associated with movement along the Las Vegas Valley shear zone occurred after 15.67 ± 0.10 Ma (2 sigma ), based on a 40 Ar/ 39 Ar date from a tuff in the Gass Peak formation in the southern Las Vegas Range. Basaltic magmatism in the western Lake Mead area began as early as 13.28 ± 0.09 Ma, based on a date from a basalt flow in the Lovell Wash Member of the Horse Spring Formation. Isotopic dating of a basalt from the volcanic rocks of Callville Mesa indicates that these rocks are as old as 11.41 ± 0.14 Ma, suggesting that volcanic activity began shortly after formation of the Boulder basin, the extensional basin in which the informally named red sandstone unit was deposited. The red sandstone unit is at least as old as 11.70 ± 0.08 Ma and contains megabreccia deposits younger than 12.93 ± 0.10 Ma. This result shows that formation of the Boulder basin was associated with development of topographic relief that was probably generated by movement along the Saddle Island low-angle normal fault. Stratal tilting associated with extension occurred both prior to and after 11.5 Ma.

Nevada↗

Gas shale/oil shale

The production of natural gas from shales continues to increase in North America, and shale gas exploration is on the rise in other parts of the world since the previous report by this committee was published by American Association of Petroleum Geologists, Energy Minerals Division (2009). For the United States, the volume of proved reserves of natural gas increased 11% from 2008 to 2009, the increase driven largely by shale gas development (Energy Information Administration 2010c). Furthermore, shales have increasingly become targets of exploration for oil and condensate as well as gas, which has served to greatly expand their significance as ‘‘unconventional’’ petroleum reservoirs. This report provides information about specific shales across North America and Europe from which gas (biogenic or thermogenic), oil, or natural gas liquids are produced or is actively being explored. The intent is to reflect the recently expanded mission of the Energy Minerals Division (EMD) Gas Shales Committee to serve as a single point of access to technical information on shales regardless of the type of hydrocarbon produced from them. The contents of this report were drawn largely from contributions by numerous members of the EMD Gas Shales Advisory Committee, with much of the data being available from public websites such as state or provincial geological surveys or other public institutions. Shales from which gas or oil is being produced in the United States are listed in alphabetical order by shale name. Information for Canada is presented by province, whereas for Europe, it is presented by country.

Natural Resources Research↗

Science data in support of environmental health studies in the U.S.-Mexico border region

The border region of the United States and Mexico encompasses a vast and diverse array of physical settings and habitats that include wetlands, deserts, rangeland, mountains, and forests, which are unique in terms of the diversity of their water, mineral, and biological resources. The region is interconnected economically, politically, and socially owing to its binational heritage. In 1995, nearly 11 million people lived immediately adjacent to the border. By one account, that population could more than double by 2020. This rapid population growth and consequent economic development and land-use changes are pushing the limits of environmental sustainability and quality. Infrastructure development has lagged behind the rapid growth of the region, resulting in a shortage of water for municipal, agricultural, and industrial uses. These stressors threaten the quality of life in the region and raise concerns about the interdependence of environmental quality and human health. To allow for continued economic growth while protecting the area’s natural resources and fostering a high quality of life, the United States and Mexico need an improved understanding of the threats posed by these anthropogenic changes. Issues of particular concern include (1) contaminants in ground water, surface water, and biota from agricultural, municipal, and industrial activities; (2) airborne pollutants from fossil-fuel combustion and other activities; (3) contaminants from past and present mining activities and mineral deposits; and (4) pathogens, pharmaceuticals, hormones, and other contaminants released in treated and untreated human and animal wastewaters.

Fact Sheet↗

Geologic map of science study area 8, Apollinaris Patera region of Mars

Volcanoes are among the most imposing and geologically interesting features on Mars. Nearly 60 percent of the planet’s surface is covered by volcanic rocks dating from the Early Noachian to Late Amazonian Epochs (Tanaka and others, 1988). This map of the volcano Apollinaris Patera and surrounding area is one of a series of large-scale (1:500,000) geologic maps initiated by the National Aeronautics and Space Administration to investigate areas of particular scientific interest. The areas selected for mapping contain candidate landing sites for future sample-return missions to Mars (fig. 1). The map area is considered to be of special scientific interest for several reason: (1) it includes the prominent volcano Apollinaris Patera, a type of volcanic edifice unusual on Mars in that it is not associated with significant faulting and is partly surrounded by a basal scarp similar to that of its much larger counterpart at the base of Olympus Mons; (2) it is located in a major transition zone between ancient highlands to the south and much of the younger lowland plains to the north; (3) rocks have different origins and a ide range of ages occurring in the area; and (4) erosional processes associated with fluvial, volcanic, and eolian activity have shaped the terrain. The map area’s potential as a landing site is increased by its extensive, relatively smooth areas at low elevation (0 to 1 km), which would permit access by an automated vehicle and atmospheric breaking by a landing craft.

IMAP↗

Toxicity assessment of groundwater contaminated by petroleum hydrocarbons at a well-characterized, aged, crude oil release site

Management of petroleum-impacted waters by monitored natural attenuation requires an understanding of the toxicology of both the original compounds released and the transformation products formed during natural breakdown. Here, we report data from a groundwater plume consisting of a mixture of crude oil compounds and transformation products in an effort to bridge the gap between groundwater quality information and potential biological effects of human exposures. Groundwater samples were characterized for redox processes, concentrations of nonvolatile dissolved organic carbon (NVDOC) and total petroleum hydrocarbons in the diesel range, as well as for activation of human nuclear receptors (hNR) and toxicologically relevant transcriptional pathways. Results show upregulation of several biological pathways, including peroxisome proliferator-activated receptor gamma and alpha, estrogen receptor alpha, and pregnane X receptor (PXR) with higher levels of hNR activity observed in more contaminated samples. Our study of affected groundwater contaminated by a crude-oil release 39 years ago shows these types of waters may have the potential to cause adverse impacts on development, endocrine, and liver functioning in exposed populations. Additionally, positive trends in activation of some of the molecular targets (e.g., PXR) with increasing NVDOC concentrations (including polar transformation products) demonstrate the importance of improving our understanding of the toxicity associated with the unknown transformation products present in hydrocarbon-impacted waters. Our results begin to provide insight into the potential toxicity of petroleum-impacted waters, which is particularly timely given the ubiquitous nature of waters impacted by petroleum contamination not only recently but also in the past and the need to protect drinking-water quality.

Environmental Science & Technology↗

Profiling lunar dust dissolution in aqueous environments: The design concept

Published studies and internal NASA reports indicate that when native lunar dust is suspended in an aqueous solution a variety of metal and other ions are released. This release has implications for future lunar missions, ranging from effects on mission hardware, effects on life support systems, possible direct effects on human health, and effects on research experiments such as plant growth experiments, space biology experiments and any activities that may involve the use of water sourced from the lunar poles. Furthermore, such contaminants could become concentrated or chemically altered to a more hazardous form during a variety of lunar mission activities, including everything from space suit cleaning to lunar industrial materials extraction. The exact profile of the release of ions from lunar dust and the nature of the partially dissolved particles has not been explored. Any model of this dissolution must be based on an understanding of the unique micromorphology of lunar dust, including its glassy nature, agglutinate features, high surface area and the presence of small deposits of elemental iron (nanophase iron) located near the surface of the grain particles. Dust has a very high surface area available for interaction with water. For this reason, on first exposure to water, an immediate pulsed release of ions could occur, with more prolonged release taking place over months or years. The few studies that have been conducted previously have been limited in both the time scales examined and in the selection of ions that were measured. The proposed investigation is a comprehensive materials science investigation, using the most modern analytical tools to catalogue all metals given off from lunar dust in various aqueous solutions and their time profiles of release from the very short term to the very long term. The product of the proposed study will be a comprehensive database determined from NASA curated samples collected from the Apollo landing sites that can be applied to research in both living systems and non-living systems on the moon. The methods developed in the proposed study will also establish standards for analysis of lunar dust samples returned from future manned missions (Artemis and others) and future robotic missions. The knowledge gained from this basic materials science investigation will have broad impact on the design of engineered human safety and health systems.

Acta Astronautica↗

Effects of particulate carbonaceous matter on the bioavailability of benzo[a]pyrene and 2,2‘,5,5‘-tetrachlorobiphenyl to the clam, Macoma balthica

We investigated the bioavailability via diet of spiked benzo[ a ]pyrene (BaP) and 2,2‘,5,5‘-tetrachlorobiphenyl (PCB-52) from different carbonaceous (non-carbonate, carbon containing) particle types to clams ( Macoma balthica ) collected from San Francisco Bay. Our results reveal significant differences in absorption efficiency between compounds and among carbonaceous particle types. Absorption efficiency for PCB-52 was always greater than that for BaP bound to a given particle type. Among particles, absorption efficiency was highest from wood and diatoms and lowest from activated carbon. Large differences in absorption efficiency could not be simply explained by comparatively small differences in the particles' total organic carbon content. BaP and PCB-52 bound to activated carbon exhibited less than 2% absorption efficiency and were up to 60 times less available to clams than the same contaminants associated with other types of carbonaceous matter. These results suggest that variations in the amount and type of sediment particulate carbonaceous matter, whether naturally occurring or added as an amendment, will have a strong influence on the bioavailability of hydrophobic organic contaminants. This has important implications for environmental risk assessment, sediment management, and development of novel remediation techniques.

Environmental Science & Technology↗

Feather lead concentrations and 207Pb/206Pb ratios reveal lead exposure history of California Condors (Gymnogyps californianus)

Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor ( Gymnogyps californianus ). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only ∼10% of a bird’s annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird’s lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2−4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant of population health, our findings should increase the understanding of population-level effects from lead poisoning in condors; this information may also be helpful for other avian species potentially impacted by lead poisoning.

California↗

Surficial geology of the lower Comb Wash, San Juan County, Utah

The surficial geologic map of lower Comb Wash was produced as part of a master’s thesis for Northern Arizona University Quaternary Sciences program. The map area includes the portion of the Comb Wash alluvial valley between Highway 163 and Highway 95 on the Colorado Plateau in southeastern Utah. The late Quaternary geology of this part of the Colorado Plateau had not previously been mapped in adequate detail. The geologic information in this report will be useful for biological studies, land management and range management for federal, state and private industries. Comb Wash is a south flowing ephemeral tributary of the San Juan River, flanked to the east by Comb Ridge and to the west by Cedar Mesa (Figure 1). The nearest settlement is Bluff, about 7 km to the east of the area. Elevations range from 1951 m where Highway 95 crosses Comb Wash to 1291 m at the confluence with the San Juan River. Primary vehicle access to lower Comb Wash is provided by a well-maintained dirt road that parallels the active channel of Comb Wash between Highway 163 and Highway 95. For much of the year this road can be traversed without the aid of four-wheel drive. However, during inclement weather such as rain or snow the road becomes treacherous even with four-wheel drive. The Comb Wash watershed is public land managed by the Bureau of Land management (BLM) office in Monticello, Utah. The semi-arid climate of Comb Wash and the surrounding area is typical of the Great Basin Desert. Temperature in Bluff, Utah ranges from a minimum of –8° C in January to a maximum of 35° C in July with a mean annual temperature of 9.8° C (U.S. Department of Commerce, 1999). The difference between day and nighttime temperatures is as great as 20° C. Between 1928 and 1998, annual rainfall in Bluff averaged 178 mm per year (U.S. Department of Commerce, 1999). Annual rainfall in Comb Wash averaged 240 mm per year from 1991 to 1999 while Bluff received an average of 193 mm for the same 8 year period. Most precipitation is monsoonal, convective storms that bring moisture from the Gulf of Mexico beginning in early July and ending by October. Large frontal storms during December and January are responsible for most winter precipitation (Figure 2). The record from U.S. Geological Survey gauging station number 09379000 operated by the BLM from 1959 through 1968 indicates that Comb Wash flows in direct response to precipitation events. Most daily discharge and peak events occur in late July through September, coinciding with high intensity monsoon thunderstorms. Comb Wash supports a variety of vegetation typical of the Great Basin Desert and the northern desert shrub zone as described by Fowler and Koch (1982). On the lower alluvial terraces, bushes and shrubs dominate the vegetation, including: sagebrush (Artemesia tridentata), rabbitbrush (Chrysothamnus nauseosus), fourwing saltbush (Atriplex canescens), winterfat (Eurotia lanata), greasewood (Sarcobatus vermiculatus), and shadscale (Atriplex concertifolia). Juniper trees (Juniperus osteosperma) can be found on the rocky colluvial slopes near Comb Ridge and on the higher terrace near Cedar Mesa. The floodplain contains an abundance of riparian vegetation including cottonwood (Populus fremontii), willow (Salix exigua), and tamarisk (Tamarix ramosissima). Tamarisk is one of 7 non-native species present in the lower Comb Wash watershed. At least seven known species of noxious weeds have invaded the watershed, including Bermuda grass (Cynodon dactylon), field bindweed (Convolvulus avensis), Canada thistle (Cirsium arvense), Russian knapweed (Centaurea repens), tamarisk and camel thorn (Alhagi pseudalhagi). Of these, tamarisk or salt-cedar has most aggressively colonized the southwestern United States, including the San Juan watershed. Graf (1978) estimates that since the late 19th century, tamarisk has spread at a rate of 20 km per year. Tamarisk first appeared in Comb Wash during the mid to early 20th century based on photographs taken by Gregory in the early 1900’s (Gregory, 1938).

Utah↗

The ASTER data system: An overview of the data products in Japan and in the United States

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data system is a cooperative system, which is operated jointly by Japan’s Ministry of Economy, Trade, and Industry (METI) through its Earth Remote Sensing Data Analysis Center (ERSDAC), and by the National Aeronautics and Space Administration (NASA) primarily through its Goddard Space Flight Center (GSFC) and Land Processes (LP) Distributed Active Archive Center (DAAC). ASTER is a moderate-resolution land remote sensing system onboard the Earth Observing System (EOS) Terra spacecraft. ASTER-acquired data are received at the White Sands, New Mexico, ground receiving station, and then transmitted via land network to the EOS Data and Operations System (EDOS) within the Goddard DAAC, located at the GSFC. EDOS pre-processes raw ASTER data to Level-0 (L0) data, and sends them via the high-speed Asia-Pacific Advanced Network (APAN) to the ASTER Ground Data System (GDS) in Japan. ASTER GDS processes the L0 data to level-1 (L1) datasets; they distribute these data to users, and also use them to generate higher-level products for their user community. ASTER GDS sends a copy of all L1A data they produce to NASA’s LP DAAC, located at the U.S. Geological Survey’s Center for Earth Resources Observation and Science (EROS) near Sioux Falls, South Dakota. All L1 data received from Japan are ingested, archived, and available for users at LP DAAC. The LP DAAC also generates and distributes higher-level products from L1 data based on requests from users. To meet time-critical needs related to sensor health and performance, natural disasters, national emergencies, and certain field campaigns, the ASTER Expedited Data System (EDS) was developed, and is operated jointly by U.S. and Japanese partners.

Book chapter↗

USGS Workshop on Scientific Aspects of a Long-Term Experimental Plan for Glen Canyon Dam, April 10-11, 2007, Flagstaff, Arizona

Executive Summary Glen Canyon Dam is located in the lower reaches of Glen Canyon National Recreation Area on the Colorado River, approximately 15 miles upriver from Grand Canyon National Park (fig. 1). In 1992, Congress passed and the President signed into law the Grand Canyon Protection Act (GCPA; title XVIII, sec. 1801?1809, of Public Law 102-575), which seeks ?to protect, mitigate adverse impacts to, and improve the values for which Grand Canyon National Park and Glen Canyon National Recreation Area were established.? The Glen Canyon Dam Adaptive Management Program (GCDAMP) was implemented as a result of the 1996 Record of Decision on the Operation of Glen Canyon Dam Final Environmental Impact Statement to ensure that the primary mandate of the GCPA is met through advances in information and resources management (U.S. Department of the Interior, 1995). On November 3, 2006, the Bureau of Reclamation (Reclamation) announced it would develop a long-term experimental plan environmental impact statement (LTEP EIS) for operational activities at Glen Canyon Dam and other management actions on the Colorado River. The purpose of the long-term experimental plan is twofold: (1) to increase the scientific understanding of the ecosystem and (2) to improve and protect important downstream resources. The proposed plan would implement a structured, longterm program of experimentation to include dam operations, potential modifications to Glen Canyon Dam intake structures, and other management actions such as removal of nonnative fish species. The development of the long-term experimental plan continues efforts begun by the GCDAMP to protect resources downstream of Glen Canyon Dam, including Grand Canyon, through adaptive management and scientific experimentation. The LTEP EIS will rely on the extensive scientific studies that have been undertaken as part of the adaptive management program by the U.S. Geological Survey?s (USGS) Grand Canyon Monitoring and Research Center (GCMRC), one of the four research stations within the USGS Southwest Biological Science Center. On April 10 and 11, 2007, at the behest of Reclamation, the GCMRC convened a workshop with scientific experts to identify one or more scientifically credible, long-term experimental options for Reclamation to consider for the LTEP EIS that would be consistent with the purpose and need for the plan. Workshop participants included government, academic, and private scientists with broad experience in the Colorado River in Grand Canyon and regulated rivers around the world. Resource managers and GCDAMP participants were also present on the second day of the workshop. In advance of the workshop, Reclamation and LTEP EIS cooperating agencies identified 14 core scientific questions. Workshop participants were asked to consider how proposed options would address these questions, which fall primarily into four areas: (1) conservation of endangered humpback chub (Gila cypha) and other high-priority biological resources, (2) conservation of sediment resources, (3) enhancement of recreational resources, and (4) preservation of cultural resources. A secondary objective of the workshop was the evaluation of four long-term experimental options developed by the GCDAMP Science Planning Group (SPG) (appendix B). The flow and nonflow treatments called for in the four experimental options were an important starting point for workshop discussions. At the beginning of the workshop, participants were provided with the final LTEP EIS scoping report prepared by Reclamation. Participants were also advised that Reclamation had committed to ?make every effortEto ensure that a new population of humpback chub is established in the mainstem or one or more of the tributaries within Grand Canyon? in the 1995 Operation of Glen Canyon Dam Final Environmental Impact Statement (U.S. Department of the Interior, 1995). This decision was consistent with the U.S. Fish and Wildlife Service?s 1995 bi

Open-File Report↗

St. Louis Area Earthquake Hazards Mapping Project— A progress report-November 2008

St. Louis has experienced minor earthquake damage at least 12 times in the past 200 years. Because of this history and its proximity to known active earthquake zones, the St. Louis Area Earthquake Hazards Mapping Project (SLAEHMP) is producing digital maps that show variability of earthquake hazards, including liquefaction and ground shaking, in the St. Louis area. The maps will be available free via the internet. Although not site specific enough to indicate the hazard at a house-by-house resolution, they can be customized by the user to show specific areas of interest, such as neighborhoods or transportation routes. Earthquakes currently cannot be predicted, but scientists can estimate how strongly the ground is likely to shake as the result of an earthquake. Earthquake hazard maps provide one way of conveying such estimates. The U.S. Geological Survey (USGS), which produces earthquake hazard maps for the Nation, is working with local partners to develop detailed maps for urban areas vulnerable to strong ground shaking. These partners, which along with the USGS comprise the SLAEHMP, include the Missouri University of Science and Technology-Rolla (Missouri S&T), Missouri Department of Natural Resources (MDNR), Illinois State Geological Survey (ISGS), Saint Louis University, Missouri State Emergency Management Agency, and URS Corporation. Preliminary hazard maps covering a test portion of the 29-quadrangle St. Louis study area have been produced and are currently being evaluated by the SLAEHMP. A USGS Fact Sheet summarizing this project was produced and almost 1000 copies have been distributed at several public outreach meetings and field trips that have featured the SLAEHMP (Williams and others, 2007). In addition, a USGS website focusing on the SLAEHMP, which provides links to project results and relevant earthquake hazard information, can be found at: http://earthquake.usgs.gov/regional/ceus/urban_map/st_louis/index.php. This progress report summarizes the methodology and data used to generate these preliminary maps. For more details about many of the topics in this summary the reader is referred to the Karadeniz (2007) and Chung (2007) Ph.D. theses.

Illinois, Missouri↗