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2018

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Articles 211 - 240 of 1193

Full-Text Articles in Earth Sciences

Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren Oct 2018

Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren

Geography & Environment Publications

Planimetric change was measured on daily hydrographs over two meltwater seasons using time-lapse images of the proglacial, gravel, braided, Sunwapta River, Canada. Significant planimetric change occurred on 10-15 days per year. Area of planimetric change correlated with peak and total daily meltwater hydrograph discharge. A clear threshold discharge can be identified below which no planform activity occurs, an intermediate range over which change occurs conditionally, and a peak flow range at which significant change always occurs. Field conditions were reproduced in a physical model in a laboratory flume. Photogrammetric DEMs of bed morphology and measurements of bedload output were made …


Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter Oct 2018

Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter

USF Tampa Graduate Theses and Dissertations

Analyses of foraminiferal assemblages involve time consuming microscopic assessment of sediment samples. Image recognition software, which systematically matches features within sample images against an image library, is widely used in contexts ranging from law enforcement to medical research. At present, scientific applications such as identification of specimens in plankton samples utilize flow through systems in which samples are suspended in liquid and pass through a beam of light where the images are captured using transmitted light. Identification of foraminifers generally utilizes reflected light, because most shells are relatively opaque.

My goal was to design and test a protocol to directly …


The Sedimentology And Origins Of A Giant Mass Transport Complex: The Nataraja Slide, Arabian Sea, Sarah Dailey Oct 2018

The Sedimentology And Origins Of A Giant Mass Transport Complex: The Nataraja Slide, Arabian Sea, Sarah Dailey

LSU Master's Theses

A giant mass transport complex (MTC) was recently discovered in the eastern Arabian Sea exceeding in volume all but one other known complex on passive margins worldwide. The complex, named the Nataraja Slide, was drilled by IODP Expedition 355 in two locations where it is ~300 m (Site U1456) and ~200 m thick (Site U1457). The top is defined by the presence of both reworked microfossil assemblages and deformation structures, such as folding and faulting. The deposit consists of two main phases of mass wasting, each which consists of smaller pulses, with generally fining upward cycles, all emplaced just prior …


Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock Oct 2018

Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Nutrient Addition And Drought Interact To Change The Structure And Decrease The Functional Diversity Of A Mediterranean Grassland, Carla Nogueira, Alice Nunes, Miguel N. Bugalho, Cristina Branquinho, Rebecca L. Mcculley, Maria Conceição Caldeira Oct 2018

Nutrient Addition And Drought Interact To Change The Structure And Decrease The Functional Diversity Of A Mediterranean Grassland, Carla Nogueira, Alice Nunes, Miguel N. Bugalho, Cristina Branquinho, Rebecca L. Mcculley, Maria Conceição Caldeira

Plant and Soil Sciences Faculty Publications

Anthropogenic activities are increasing nutrient availability and altering precipitation regimes. This may lead to critical changes in grasslands functioning. This is particularly important for grasslands in the Mediterranean Basin that have evolved in nutrient poor soils, and where more frequent and prolonged droughts are projected to occur. However, there is limited knowledge regarding the interacting effects of multiple nutrient inputs and rainfall variability on the plant functional structure and diversity of Mediterranean grasslands. We conducted a nutrient addition experiment in a Mediterranean grassland during four contrasting precipitation years. We established four treatments that varied in the number of added nutrients, …


Bifurcation Of Plankton Community And Its Impact On Dms Distribution In The Southern Ocean, Kelin Zhuang Oct 2018

Bifurcation Of Plankton Community And Its Impact On Dms Distribution In The Southern Ocean, Kelin Zhuang

Earth & Environmental Sciences Datasets - Archive

Submitted to Journal of Geophysical Research Biogeosciences Title: Bifurcation of plankton community and its impact on DMS distribution in the Southern Ocean - A Simulated Response to Elevated CO2 Radiative Forcing Data and code


Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson Oct 2018

Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson

Geosciences Faculty Publications

Pluvial-lake highstands in the Bonneville basin are known to be contemporaneous with periods of Quaternary glaciation. At least five lake cycles have been identified from prior studies of two deep cores (Eardley and Gvosdetsky, 1960; Eardley and others, 1973) and several isolated outcrops in the main part of the Bonneville basin and eastward in Cache Valley. These are the Lava Creek B (~620 ka, marine isotope stage MIS 16), Pokes Point (~420 ka, MIS12), Little Valley (~150 ka, MIS 6), Cutler Dam (~60 ka, MIS 4), and Bonneville (~18 ka, MIS 2) lake cycles (Oviatt and others ,1987, 1999; Lisiecki …


Cache Valley: A Critical Part Of Lake Bonneville Preserves Evidence For A Protracted Bonneville Highstand, Possible Tectonic Triggers Of The Bonneville Flood, Liquefaction, And Clustered Earthquakes On The East And West Cache Fault Zones, Susanne U. Jänecke, Robert Q. Oaks Jr., Tammy M. Rittenour, A. J. Knight, Justin Oakeson, Nathan Ellis Oct 2018

Cache Valley: A Critical Part Of Lake Bonneville Preserves Evidence For A Protracted Bonneville Highstand, Possible Tectonic Triggers Of The Bonneville Flood, Liquefaction, And Clustered Earthquakes On The East And West Cache Fault Zones, Susanne U. Jänecke, Robert Q. Oaks Jr., Tammy M. Rittenour, A. J. Knight, Justin Oakeson, Nathan Ellis

Geosciences Faculty Publications

Geologic, geomorphic, and geophysical analyses of landforms, sediments, and structures in conjunction with new radiocarbon (14C) and optically stimulated luminescence (OSL) age determinations document a revised history of flooding and recession of Lake Bonneville in Cache Valley, Idaho and Utah. The presence of wave-cut cliffs in bedrock throughout the Bonneville basin show that the Bonneville highstand was protracted. Triangular facets were cut into bedrock in the footwalls of normal faults, and were steepened significantly by wave erosion at the highest Bonneville shoreline.


Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri Oct 2018

Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri

Publications and Research

Water risk management is a ubiquitous challenge faced by stakeholders in the water or agricultural sector. We present a methodological framework for forecasting water storage requirements and present an application of this methodology to risk assessment in India. The application focused on forecasting crop water stress for potatoes grown during the monsoon season in the Satara district of Maharashtra. Pre-season large-scale climate predictors used to forecast water stress were selected based on an exhaustive search method that evaluates for highest ranked probability skill score and lowest root-mean-squared error in a leave-one-out cross-validation mode. Adaptive forecasts were made in the years …


On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane Oct 2018

On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane

International Journal of Speleology

Seven silica biospeleothems from Cueva Charles Brewer, Chimantá Plateau, Venezuela have been successfully U-Th dated despite very low U and high detrital Th concentrations. Growth rates are low, between ~100 to ~800 µm/ka, and are greater closer to water level. Dates in unaltered material are in good stratigraphic order, but secondary silicification may compromise the U-Th system, yielding unreliable sequences of ages. Detritally-enriched layers correlate with global climate cycles of the Late Quaternary, in particular the cooler, drier phases of MIS 5d, 5a, and 4. SEM studies indicate that the peloidal material is made up of silica nano-particles assembled to …


The Bear River's Diversion, The Cutting Of Oneida Narrows At 55-50 Ka, And Relations To The Lake Bonneville Record, Joel Pederson, Tammy M. Rittenour, Susanne U. Jänecke, Robert Q. Oaks Jr. Oct 2018

The Bear River's Diversion, The Cutting Of Oneida Narrows At 55-50 Ka, And Relations To The Lake Bonneville Record, Joel Pederson, Tammy M. Rittenour, Susanne U. Jänecke, Robert Q. Oaks Jr.

Geosciences Faculty Publications

The Bear River's course has shifted over Quaternary time, and its late Pleistocene integration into the Bonneville basin long has been recognized as a possible explanation for why Lake Bonneville was apparently larger than the preceding lakes in its basin, and the only one to overflow its topographic threshold.

The middle-Pleistocene Bear River joined the Snake River to the north, likely via the Portneuf River drainage. Then an episode of volcanism in the Blackfoot-Gem Valley volcanic field ~100–50 ka diverted the Bear River southward into Gem Valley. Previous chronostratigraphic and isotopic work on the Main Canyon Formation in southern Gem …


Influence Of Phosphate On Tungstate Sorption On Hematite: A Macroscopic And Spectroscopic Evaluation Of The Mechanism, Bryan Sallman, Sudipta Rakshit, Grégory Lefèvre Oct 2018

Influence Of Phosphate On Tungstate Sorption On Hematite: A Macroscopic And Spectroscopic Evaluation Of The Mechanism, Bryan Sallman, Sudipta Rakshit, Grégory Lefèvre

Agricultural and Environmental Sciences Faculty Research

The environmental fate of the tungstate (VI) oxyanion [ e.g. mono tungstate and several polytungstate, generally expressed by W (VI)] is largely controlled by sorption on soil minerals, especially on iron oxide minerals. Molecular scale evaluation of W (VI) retention on iron oxides in the presence of competing oxyanions is scarce in literature. Here we report surface interaction mechanisms of W (VI) on hematite in the presence of phosphate (P) using macroscopic and in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic experiments. Batch sorption experiments were conducted using 2 g L−1 hematite and 100 μM W (VI) and …


Growth, Yield Performance And Quality Parameters Of Three Early Flowering Chia (Salvia Hispanica L.) Genotypes Cultivated In Southwestern Germany, Samantha J. Grimes, Timothy D. Phillips, Volker Hahn, Filippo Capezzone, Simone Graeff-Hönninger Oct 2018

Growth, Yield Performance And Quality Parameters Of Three Early Flowering Chia (Salvia Hispanica L.) Genotypes Cultivated In Southwestern Germany, Samantha J. Grimes, Timothy D. Phillips, Volker Hahn, Filippo Capezzone, Simone Graeff-Hönninger

Plant and Soil Sciences Faculty Publications

The combination of consumer’s ongoing demand for chia (Salvia hispanica L.) alongside the increased demand for regionally produced food products provided the impetus for this study. Its aim was to test if a regional cultivation of new chia genotypes, which were adapted to day lengths greater than 12 h, is feasible under Central European conditions. Therefore, three early flowering chia genotypes (Sahi Alba 914, W13.1, G8) were cultivated in a randomized block design at two experimental stations in Southwestern Germany (Ihinger Hof, Eckartsweier) over the course of two years (2015, 2016). Mean yields ranged from 100 to 1290 kg …


Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Saptashati Biswas, Mohammedreza Shafieifini, Xu Li, Matteo D'Alessio, Laura Carter, J. Brett Sallach Oct 2018

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Saptashati Biswas, Mohammedreza Shafieifini, Xu Li, Matteo D'Alessio, Laura Carter, J. Brett Sallach

Daugherty Water for Food Global Institute: Faculty Publications

A total of 75 papers published in 2017 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes, and engineered nanoparticles agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Fate and Occurrence, Pharmaceutical Metabolites, Anthelmintics, Antibiotic Resistance Genes, and Engineered Nanomaterials.


Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus Oct 2018

Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus

Robert F. Diffendal, Jr., Publications

Geologic mapping in Nebraska and environs is an ongoing endeavor that has spanned more than 170 years, involved dozens of scientists, and evolved through many changes. Digital mapping has risen to dominance in the state only since 1996. Geologic mapping in Nebraska today concentrates on surficial mapping, which emphasizes materials exposed at the land surface and their relationships with landforms, and which is particularly relevant because non- bedrock geologic materials (regolith) lie at the surface across at least 87% of the state. Moreover, surfi cial geologic maps assist the understanding of groundwater and sand and gravel resources, to name a …


Simulation Of Groundwater Flow, 1895–2010, And Effects Of Additional Groundwater Withdrawals On Future Stream Base Flow In The Elkhorn And Loup River Basins, Central Nebraska—Phase Three, Amanda T. Flynn, Jennifer S. Stanton Oct 2018

Simulation Of Groundwater Flow, 1895–2010, And Effects Of Additional Groundwater Withdrawals On Future Stream Base Flow In The Elkhorn And Loup River Basins, Central Nebraska—Phase Three, Amanda T. Flynn, Jennifer S. Stanton

United States Geological Survey: Water Reports and Publications

Document abstract

The United States Geological Survey (USGS), in cooperation with the Lewis and Clark, Lower Elkhorn, Lower Loup, Lower Platte North, Lower Niobrara, Middle Niobrara, Upper Elkhorn, and the Upper Loup Natural Resources Districts, designed a study to refine the spatial and temporal discretization of a previously modeled area. This updated study focused on a 30,000-square-mile area of the High Plains aquifer and constructed regional groundwater-flow models to evaluate the effects of groundwater withdrawal on stream base flow in the Elkhorn and Loup River Basins, Nebraska. The model was calibrated to match groundwater-level and base-flow data from the stream-aquifer …


Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur Oct 2018

Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur

Masters Theses & Specialist Projects

This study investigates Mio-Pliocene mass-transport deposits (MTDs) in an understudied, hydrocarbon-rich region of the northeastern Gulf of Mexico. The research utilizes a high-quality 3D seismic dataset with an area of 635 km2, along with wireline logs and biostratigraphic data. With the help of quantitative seismic geomorphology techniques, detailed mapping of MTDs suggests a complex erosional and depositional history. Deposition of a MTD unit resulted in a 180 m topographic high that substantially influenced the distribution and morphology of subsequent MTDs, specifically the bifurcation of later mass-transport flows. This bifurcation contributed to the generation of a non-shielded erosional remnant with an …


Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden Oct 2018

Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden

Masters Theses & Specialist Projects

The geology of Ethiopia is dominated by the Ethiopian Plateau that is similar in elevation to, but aerially larger than, the Colorado Plateau. Several rivers have incised through the plateau, creating gorges that reach up to 1.5 km in depth. The plateau uplifted to its current elevation and was subsequently incised sometime after the Oligocene flood basalt event that signaled the arrival of the African Superplume below Kenya and Ethiopia. Due to its size and extent, published climate modeling has indicated that Late Cenozoic plateau formation could have been a driving force in the East African Cenozoic climate changes. Although …


Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley Oct 2018

Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley

Masters Theses & Specialist Projects

The response of a karst aquifer to storm events is often faster and more severe than that of a non-karst aquifer. This distinction is often problematic for planners and municipalities, because karst flooding does not typically occur along perennial water courses; thus, traditional flood management strategies are usually ineffective. The City of Bowling Green (CoBG), Kentucky is a representative example of an area plagued by karst flooding. The CoBG, is an urban karst area (UKA), that uses Class V Injection Wells to lessen the severity of flooding. The overall effectiveness, siting, and flooding impact of Injection Wells in UKA’s is …


Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle Oct 2018

Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle

Masters Theses & Specialist Projects

Greenhouse gases (GHGs) are a major global environmental concern, because their concentrations have continuously increased over the past few centuries, due to global population growth, fossil fuel dependency, and the Industrial Revolution. Since these gases are naturally occurring phenomena, they will never be completely eliminated. Efforts to reduce them span numerous scientific attempts, with minimal improvements in reducing their atmospheric concentrations. In agricultural land practices, greenhouse gases are common byproducts that affect the atmosphere and, potentially, the groundwater where livestock and fertilizers are key contributors. Little is known about the fate of such greenhouse gases in dissolved form, known as …


Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment, Hali Steinmann Oct 2018

Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment, Hali Steinmann

Masters Theses & Specialist Projects

Much of the pioneering work on caves of the Cumberland Plateau (province spanning Tennessee, Kentucky, Alabama, and Georgia) has been stratigraphically located within the Mississippian Bangor and Monteagle Limestones, wherein some of the region’s largest and most spectacular caves occur. Of interest to the understanding of this karst landscape, but severely underrepresented in the literature thereof, are caves and karst features in a heterogeneous sequence of clastics and carbonates known collectively as the Pennington Formation (Upper Mississippian). This work consisted of a regional study of Pennington caves on the western Cumberland Plateau escarpment (Alabama and Tennessee), and a case study …


Land-Use Impacts On The Hydrology Of The Hidden River Groundwater Subbasin, Horse Cave, Hart County, Kentucky, Cesalea N. Osborne Oct 2018

Land-Use Impacts On The Hydrology Of The Hidden River Groundwater Subbasin, Horse Cave, Hart County, Kentucky, Cesalea N. Osborne

Masters Theses & Specialist Projects

No abstract provided.


Droughtscape, Fall 2018, National Drought Mitigation Center Oct 2018

Droughtscape, Fall 2018, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the director

Drought greatly improves in Southern Plains and South

Texas, Missouri, and Colorado logged late-summer impacts

Memory, remote sensing and a new research methodology

Navigating the U.S. Drought Monitor

Planners discuss the barriers to effective drought mitigation planning

Exploring climate issues from a county management perspective

Strategic Framework for Drought Risk Management and Enhancing Resilience in Africa

Mena global policy forum looks from data to mitigation

About us

State-by-state drought classification table developed by NDMC graduate student


Iac Gene Expression In The Indole-3-Acetic Acid-Degrading Soil Bacterium Enterobacter Soli Lf7, Isaac V. Greenhut, Beryl L. Slezak, Johan H. J. Leveau Oct 2018

Iac Gene Expression In The Indole-3-Acetic Acid-Degrading Soil Bacterium Enterobacter Soli Lf7, Isaac V. Greenhut, Beryl L. Slezak, Johan H. J. Leveau

Plant and Soil Sciences Faculty Publications

We show for soil bacterium Enterobacter soli LF7 that the possession of an indole-3-acetic acid catabolic (iac) gene cluster is causatively linked to the ability to utilize the plant hormone indole-3-acetic acid (IAA) as a carbon and energy source. Genome-wide transcriptional profiling by mRNA sequencing revealed that these iac genes, chromosomally arranged as iacHABICDEFG and coding for the transformation of IAA to catechol, were the most highly induced (>29-fold) among the relatively few (iac cluster were genes for a major facilitator superfamily protein (mfs) and enzymes of the β-ketoadipate pathway (pcaIJD-catBCA), which channels …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- October 2018, Natalie Umphlett, Rezaul Mamood, Jamie Lahowetz, Warren Pettee, Dalton Van Stratten, Crystal J. Stiles Oct 2018

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- October 2018, Natalie Umphlett, Rezaul Mamood, Jamie Lahowetz, Warren Pettee, Dalton Van Stratten, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the interim director........................................1

Staff spotlight...........................1

ACIS GIS portal release..........2

ACIS maps enhancement.....3

Product highlight....................4

Update on regional climate conditions..................................4

Update on tribal engagement............................................. 5

Recent and upcoming travel and activities.............................6


Direct Insertion Of Nasa Airborne Snow Observatory-Derived Snow Depth Time Series Into The Isnobal Energy Balance Snow Model, Andrew R. Hedrick, Hans-Peter Marshall Oct 2018

Direct Insertion Of Nasa Airborne Snow Observatory-Derived Snow Depth Time Series Into The Isnobal Energy Balance Snow Model, Andrew R. Hedrick, Hans-Peter Marshall

CGISS Publications and Presentations

Accurately simulating the spatiotemporal distribution of mountain snow water equivalent improves estimates of available meltwater and benefits the water resource management community. In this paper we present the first integration of lidar-derived distributed snow depth data into a physics-based snow model using direct insertion. Over four winter seasons (2013–2016) the National Aeronautics and Space Administration/Jet Propulsion Laboratory (NASA/JPL) Airborne Snow Observatory (ASO) performed near-weekly lidar surveys throughout the snowmelt season to measure snow depth at high resolution over the Tuolumne River Basin above Hetch Hetchy Reservoir in the Sierra Nevada Mountains of California. The modeling component of the ASO program …


Climate Change And Curtailment: Evaluating Water Management Practices In The Context Of Changing Runoff Regimes In A Snowmelt-Dominated Basin, Amy L. Steimke, Bangshuai Han, Jodi S. Brandt, Alejandro N. Flores Oct 2018

Climate Change And Curtailment: Evaluating Water Management Practices In The Context Of Changing Runoff Regimes In A Snowmelt-Dominated Basin, Amy L. Steimke, Bangshuai Han, Jodi S. Brandt, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Hydrologic scientists and water resource managers often focus on different facets of flow regimes in changing climates. The objective of this work is to examine potential hydrological changes in the Upper Boise River Basin, Idaho, USA in the context of biophysical variables and their impacts a key variable governing administration of water resources in the region in an integrated way. This snowmelt-dominated, mountainous watershed supplies water to a semi-arid, agriculturally intensive, but rapidly urbanizing, region. Using the Envision integrated modeling framework, we created a hydrological model to simulate hydrological response to the year 2100 using six alternative future climate trajectories. …


Imaging Spectroscopic Analysis Of Biochemical Traits For Shrub Species In Great Basin, Usa, Yi Qi, Susan L. Ustin, Nancy F. Glenn Oct 2018

Imaging Spectroscopic Analysis Of Biochemical Traits For Shrub Species In Great Basin, Usa, Yi Qi, Susan L. Ustin, Nancy F. Glenn

Geosciences Faculty Publications and Presentations

The biochemical traits of plant canopies are important predictors of photosynthetic capacity and nutrient cycling. However, remote sensing of biochemical traits in shrub species in dryland ecosystems has been limited mainly due to the sparse vegetation cover, manifold shrub structures, and complex light interaction between the land surface and canopy. In order to examine the performance of airborne imaging spectroscopy for retrieving biochemical traits in shrub species, we collected Airborne Visible Infrared Imaging Spectrometer—Next Generation (AVIRIS-NG) images and surveyed four foliar biochemical traits (leaf mass per area, water content, nitrogen content and carbon) of sagebrush (Artemesia tridentata) and …


New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding Oct 2018

New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding

Conservation and Survey Division: Faculty and Staff Publications

The term “cyclothem” was coined by Wanless & Weller (1932) to describe repetitive stratigraphic successions of Carboniferous age in Illinois. Nonetheless, comparable rhythmicity had been identified in Carboniferous rocks both in the central and eastern USA, and in Europe during the preceding century. Cyclothems were found to comprise repetitive vertical successions of sandstones, heterolithic (thinly interbedded) sandstones and mudrocks, mudrocks, limestones, and coals, in many cases with pedogenic overprinting of these lithologies. As usage of the term “cyclothem” increased, so did the diversity of successions to which the term was applied, to the point where many geologists advocated abandonment of …


Reverse-Time Migration From Rugged Topography To Image Ground-Penetrating Radar Data In Complex Environments, John H. Bradford, Janna Privette, David Wilkins, Richard Ford Oct 2018

Reverse-Time Migration From Rugged Topography To Image Ground-Penetrating Radar Data In Complex Environments, John H. Bradford, Janna Privette, David Wilkins, Richard Ford

Geosciences Faculty Publications and Presentations

In ground-penetrating radar (GPR) imaging, it is common for the depth of investigation to be on the same order as the variability in surface topography. In such cases, migration fails when it is carried out from a datum after the application of elevation statics. We introduce a reverse-time migration (RTM) algorithm based on the second-order decoupled form of Maxwell’s equations, which requires computation of only the electric field. The wavefield extrapolation is computed directly from the acquisition surface without the need for datuming. In a synthetic case study, the algorithm significantly improves image accuracy over a processing sequence in which …