Synthetic Aperture Radar Observations At Salar De Pajonales, Chile,
2023
The University Of Montana
Synthetic Aperture Radar Observations At Salar De Pajonales, Chile, Michael A. A. Mcinenly
Graduate Student Theses, Dissertations, & Professional Papers
Remotely sensed microwave radars provide the spatial and temporal coverage needed to improve our understanding of the relationship between moisture content and salt pan mineralogy and, ultimately, climate variability. Moisture content in the surface and near-surface crusts found in salt pan environments, such as salt pan, has a significant impact on the backscatter values recorded by synthetic aperture radar (SAR) systems. This is because moisture affects the dielectric constant and surface roughness of the saline surface, which in turn influences the amount of electromagnetic energy reflected back to the SAR sensor. Changes in backscatter values are attributed to seasonal and …
Climatological, Hydrological, And Economic Analysis Of Agriculture In Montana And The Western U.S.A.,
2023
University of Montana, Missoula
Climatological, Hydrological, And Economic Analysis Of Agriculture In Montana And The Western U.S.A., Zachary H. Lauffenburger
Graduate Student Theses, Dissertations, & Professional Papers
Many studies have addressed the impact of climate on agriculture; however, fewer studies addressed how farmers adapt to climate change, to what extent implementation of adaptation strategies mitigates economic losses or alters the hydrologic system. Analyses of how historical climate affected not only farmer decision making, but also the economic and hydrological consequences of farmers’ adaptations to climate variations, and projections of the spatiotemporal climatic regimes at finer regional scales are critical for aiding in actionable climate change adaptations. This dissertation helps fill knowledge gaps on the impacts of climate change in rural regions of the agricultural western U.S.A. and …
Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed,
2023
University of Montana, Missoula
Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver
Graduate Student Theses, Dissertations, & Professional Papers
We evaluate the sensitivity of Earth's elastic deformation to groundwater hydraulic diffusivity using coupled groundwater and elastic deformation models. Seasonal changes in terrestrial water storage cause deformation to the Earth’s crust and deeper interior that is within the observational capacity of GPS instruments. We couple finite difference groundwater simulations with geodetic forward models of crustal displacement to investigate the ability of geodetic deformation to constrain bedrock hydrologic properties. We use MODFLOW-2005 to simulate seasonal changes in groundwater flow and storage, and then use the LoadDef elastic deformation model to forward model surface displacement caused by the change in terrestrial water …
The Dynamic Relationship Between Permafrost And Landcover In Northwestern Canada’S Discontinuous Permafrost Zone,
2023
Wilfrid Laurier University
The Dynamic Relationship Between Permafrost And Landcover In Northwestern Canada’S Discontinuous Permafrost Zone, Olivia Carpino
Theses and Dissertations (Comprehensive)
Northwestern Canada’s subarctic is among the most impacted regions in the world as it is experiencing rapid climatic and environmental change. As a result, northwestern Canada has been experiencing region-wide permafrost thaw and disappearance, both of which are also occurring at unprecedented rates. Permafrost temperatures in the Taiga Plains have been warming steadily over the last several decades, which has been particularly detrimental across its lower latitudes of the discontinuous permafrost zone where the permafrost is already relatively thin and warm. These factors indicate that permafrost in the southern Taiga Plains may be in a state of disequilibrium with the …
Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China,
2023
China University of Geosciences Beijing
Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang
Civil & Environmental Engineering Faculty Publications
Study region: The semiarid Mu Us Sandy Land (MUSL) was selected for this study. It is in the farming-pastoral ecotone of north China and functions as an eco-environmental barrier.
Study focus: Afforestation can mitigate desertification and soil erosion by improving hydrologic condition, which is particularly true for semiarid and arid regions. However, little is known about the quantitative response of hydrologic improvement to afforestation level that can be measured by leaf area index (LAI). The objective was to setup and use a physically-based model to quantitatively assess the dynamics of water fluxes from Salix psammophila afforestation in the MUSL.
New …
Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage,
2023
Old Dominion University
Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
A seawater reverse osmosis (RO) plant layout based on multistage RO with stages located at different elevations above sea level is described. The plant uses the weight of a seawater column from pumped storage as head pressure for RO (gravity-driven multistage RO) or to supplement high-pressure pumps used in RO (gravity-assisted multistage RO). The use of gravitational force reduces the specific energy for RO compared to using high-pressure pumps. By locating the RO stages at different elevations based on demand sites, the total specific energy consumption for RO and permeate transport to different elevations above sea level is reduced from …
Comparison Of Permafrost Thaw-Related Changes To Hydrological Response And Land Cover In Subarctic Peatland-Dominated Landscapes,
2023
Wilfrid Laurier University
Comparison Of Permafrost Thaw-Related Changes To Hydrological Response And Land Cover In Subarctic Peatland-Dominated Landscapes, Mikhail Mack
Theses and Dissertations (Comprehensive)
The hydrological implications of discontinuous permafrost thaw in peatland-dominated basins are not well understood. While there is evidence suggesting that permafrost-thaw-driven land cover change increases annual runoff and the runoff ratio in the Taiga Plains of northwestern Canada, few studies have evaluated the impact on small to medium-sized basins (< 105 km2) outside this ecoregion. Here, we assess runoff, runoff ratio, and precipitation trends for 34 peatland-dominated basins, of which 28 are in the discontinuous and sporadic permafrost zones and 6 in adjacent permafrost-free environments. We calculated annual and monthly trends between 1970 and 2016 using the Mann-Kendall …
Spatial And Temporal Characteristics Of Historical Surface Climate Over The Northwest Territories, Canada,
2023
Wilfrid Laurier University
Spatial And Temporal Characteristics Of Historical Surface Climate Over The Northwest Territories, Canada, Bhaleka D. Persaud
Theses and Dissertations (Comprehensive)
Climate change is putting many of the Northwest Territories (NWT) ecosystems, its people and animal populations at risk due to accelerated warming, permafrost thaw, and changing precipitation regimes. As the NWT continues to warm, at disproportionately higher rates when compared to the rest of Canada, threats to the stability of NWT’s ecosystems are expected to increase. Consequently, understanding how climate warming has changed historically and its implications on natural ecosystems requires point-to-region-specific, long-term climatic data to elucidate important drivers of observed changes relevant to decision makers at community, Indigenous, Territorial and Federal government levels. However, in situ climate data are …
Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species,
2023
Wilfrid Laurier University
Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species, Patrick Strzalkowski
Theses and Dissertations (Comprehensive)
The vast majority of the research into the performance of stormwater management ponds (SWMPs) has been performed in warm regions or during the warmer seasons in temperate regions. It is presumed that SWMPs are inactive in the winter as any potential stormwater is trapped in snow and ice. The main goal of this thesis was to test this presumption and to study the dynamics and performance of three SWMPs during the winter. Remote water level loggers were installed into the three SWMPs and daily grab samples from the influents and effluents were taken and analyzed for total phosphorus (TP), chloride, …
Controls On Thermokarst Lake Water Balances In The Inuvik - Tuktoyaktuk Region,
2023
Wilfrid Laurier University
Controls On Thermokarst Lake Water Balances In The Inuvik - Tuktoyaktuk Region, Evan J. Wilcox
Theses and Dissertations (Comprehensive)
There are tens of thousands of thermokarst lakes in the Inuvik-Tuktoyaktuk region, located in the northwest corner of the Northwest Territories, Canada. These lakes formed following the last glacial period in areas where ice-rich permafrost thawed and created depressions in the landscape. The Inuvik-Tuktoyaktuk region is one of the fastest warming regions in the world, leading to changing precipitation patterns, permafrost thaw and deciduous shrub expansion, all of which are affecting the water balance of thermokarst lakes. During the past several decades, lake expansion and contraction have been observed in response to fluctuations in precipitation. While these changes in lake …
Nitrite Cycling In The Primary Nitrite Maxima Of The Eastern Tropical North Pacific,
2023
Old Dominion University
Nitrite Cycling In The Primary Nitrite Maxima Of The Eastern Tropical North Pacific, Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, Karen L. Casciotti
OES Faculty Publications
The primary nitrite maximum (PNM) is a ubiquitous feature of the upper ocean, where nitrite accumulates in a sharp peak at the base of the euphotic zone. This feature is situated where many chemical and hydrographic properties have strong gradients and the activities of several microbial processes overlap. Near the PNM, four major microbial processes are active in nitrite cycling: ammonia oxidation, nitrite oxidation, nitrate reduction and nitrite uptake. The first two processes are mediated by the nitrifying archaeal/bacterial community, while the second two processes are primarily conducted by phytoplankton. The overlapping spatial habitats and substrate requirements for these microbes …
Spatial Analysis Of Groundwater Potential: A Firsthand Approach Towards Groundwater Development In Moroto District, Uganda,
2022
Water Offices, Moroto District Local Government, Moroto, Uganda
Spatial Analysis Of Groundwater Potential: A Firsthand Approach Towards Groundwater Development In Moroto District, Uganda, Musa W. Lowot, Augustina C. Alexander
Tanzania Journal of Science
Groundwater is a vital resource that helps mankind and development. However, in Moroto District challenges of groundwater development has increased arising from changes in rainfall patterns coupled with high abstraction from population increase. In this study, the spatial variability of groundwater potential was assessed to develop a tool that will aid decision on groundwater potential sites selection for groundwater development/exploration. The study utilized an integrated technique and tools such as Remote Sensing (RS), Geographic Information System (GIS) and Multi Criteria Decision Analysis (MCDA) in analysis and delineation of potential areas for successful groundwater development. The generated map through weighted overlay …
Historical Tsunami Observability For Izu–Bonin–Mariana Sources,
2022
Central Washington University
Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes
Geological Sciences Faculty Scholarship
The Izu–Bonin–Mariana Subduction System (IBM) is one of the longest subduction zones in the world with no instrumental history of shallow focus, great earthquakes (Mw > 8). Over the last 50 years, researchers have speculated on the reason for the absence of large magnitude, shallow seismicity on this plate interface, exploring factors from plate age to convergence rate. We approach the question from a different point of view: what if the IBM has hosted great earthquakes and no documentable evidence was left? To address the question of observability, we model expected tsunami wave heights from nine great earthquake scenarios on the …
Relative Importance Of Radar Variables For Nowcasting Heavy Rainfall: A Machine Learning Approach,
2022
Chapman University
Relative Importance Of Radar Variables For Nowcasting Heavy Rainfall: A Machine Learning Approach, Yi Victor Wang, Seung Hee Kim, Geunsu Lyu, Choeng-Lyong Lee, Gyuwon Lee, Ki-Hong Min, Menas C. Kafatos
Institute for ECHO Articles and Research
Highly short-term forecasting, or nowcasting, of heavy rainfall due to rapidly evolving mesoscale convective systems (MCSs) is particularly challenging for traditional numerical weather prediction models. To overcome such a challenge, a growing number of studies have shown significant advantages of using machine learning (ML) modeling techniques with remote sensing data, especially weather radar data, for high-resolution rainfall nowcasting. To improve ML model performance, it is essential first and foremost to quantify the importance of radar variables and identify pertinent predictors of rainfall that can also be associated with domain knowledge. In this study, a set of MCS types consisting of …
Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa,
2022
Duquesne University
Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar
Electronic Theses and Dissertations
The Sand River Catchment is an important tributary of the transboundary Limpopo River in South Africa, which spans Botswana, Mozambique, South Africa, and Mozambique. Groundwater is a critical resource in the region, especially in the context of population growth and climate change. Data are needed for proper management of these water resources. In regions where groundwater data are sparse in time, space, or both, the most promising solutions come from satellites and hydrologic models. Regional literature suggests that the Soutpansberg Mountains, located within the Sand Catchment, are high-elevation water towers with uncertain groundwater resources. Improved understanding of groundwater resources in …
Future Colorado River Basin Drought And Surplus,
2022
Chapman University
Future Colorado River Basin Drought And Surplus, Rama Bedri, Thomas Piechota
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Historical and future drought and surplus periods in the Colorado River basin are evaluated based on eight climate scenarios. Unimpaired streamflow from 17 stations in the Colorado River are evaluated based on U.S. Geological Survey, Bureau of Reclamation, and Coupled Modeled Intercomparison Projection 5 downscaled data from 1950–2099. Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios are considered for four climate models (HadGEM2-ES, CNRM-CM5, CanESM2, MI-ROC5). Drought (surplus) quantities, magnitudes, severities, and water year flows are compared for the historical and future periods. Results indicate that there is a significant difference between the historical record and future projections. The …
Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota,
2022
University of Nebraska-Lincoln
Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota, Mitchell R. Magruder
School of Natural Resources: Dissertations, Theses, and Student Research
Native species of the Missouri River drainage inhabiting benthic habitats dominate state and federal lists of species at risk. Sicklefin Chub Macrhybopsis meeki and Sturgeon Chub Macrhybopsis gelida are two native Missouri River benthic minnows that are currently under review for federal listing under the Endangered Species Act (ESA) due to extensive population declines and local extirpations within their native range. Substantial alterations to the Missouri River threaten Macrhybopsis spp. and other benthic fishes; however, large, less impacted tributaries in South Dakota may act as refugia for native species. The extent of Sicklefin Chub and Sturgeon Chub populations is largely …
Earlier Snowmelt May Lead To Late Season Declines In Plant Productivity And Carbon Sequestration In Arctic Tundra Ecosystems,
2022
San Diego State University
Earlier Snowmelt May Lead To Late Season Declines In Plant Productivity And Carbon Sequestration In Arctic Tundra Ecosystems, Donatella Zona, Peter M. Lafleur, Koen Hufkens, Barbara Bailey, Beniamino Gioli, George Burba, Jordan P. Goodrich, Anna K. Liljedahl, Eugénie S. Euskirchen, Jennifer D. Watts, Mary Farina, John S. Kimball, Martin Heimann, Mathias Göckede, Martijn Pallandt, Torben R. Christensen, Mikhail Mastepanov, Efrén López-Blanco, Marcin Jackowicz-Korczynski, Albertus J. Dolman, Luca Belelli Marchesini, Roisin Commane, Steven C. Wofsy, Charles E. Miller, David A. Lipson, Josh Hashemi, Kyle A. Arndt, Lars Kutzbach, David Holl, Julia Boike, Christian Wille, Torsten Sachs, Aram Kalhori, Xia Song
Daugherty Water for Food Global Institute: Faculty Publications
Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June …
Statistical Analysis Of Aquifer Hydraulic Properties By A Continuous Pumping Tomography Test: Application To The Boise Hydrogeophysical Research Site,
2022
Tel-Aviv University
Statistical Analysis Of Aquifer Hydraulic Properties By A Continuous Pumping Tomography Test: Application To The Boise Hydrogeophysical Research Site, Kan Bun Cheng, Gedeon Dagan, Warren Barrash, Michael Cardiff, Avinoam Rabinovich
Geosciences Faculty Publications and Presentations
Characterizing aquifer heterogeneity is paramount for accurate flow and transport modeling. In this work, we present a new approach for statistical analysis of hydraulic properties in continuous pumping tomography tests of a phreatic aquifer. The method entails determining equivalent hydraulic conductivity (Keq), specific storage (Ss,eq), and specific yield (Sy,eq) at many locations in the field and then calculating statistical moments of the equivalent properties, assuming they are random space variables. Equivalent properties are defined as the ones pertinent to a homogeneous aquifer for which the head time …
The North Platte River Valley: The Intersectionality Between Water Quality And People,
2022
University of Nebraska-Lincoln
The North Platte River Valley: The Intersectionality Between Water Quality And People, Anni Poetzl
School of Natural Resources: Dissertations, Theses, and Student Research
The North Platte River (NPR) Valley of western Nebraska is a semi-arid watershed with row crop production, livestock production, and urban land use activity and has a population of diverse stakeholders. These land use activities contribute to the enrichment of surface waters, such as streams, which can affect human and ecosystem health, as well as economic development and recreational activities. The project objectives are to: (1) quantify the movement of dissolved inorganic nutrients from the land within the NPR Valley to the NPR via tributaries and canals, (2) identify spatiotemporal variability of nutrient limitation of periphyton growth within the NPR, …
