Earth Sciences Commons^™

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 …

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 …

Silting Dynamics And Metal Contaminants In The Georgetown Inner Harbor, Ezekiel Wil Meyers

Electronic Theses and Dissertations

The Georgetown inner harbor is an abandoned oxbow-like river loop and a vital historic site with a wealth of traditional businesses and heavy local industry located within Winyah Bay. Since the modification of the Sampit River in 1949, chronic rapid silting has plagued the inner harbor. With these substantial amounts of fine-grained material accumulating inside the inner harbor, business operations along the waterfront, navigational and maritime operations, and contamination within the harbor are of major concern. The goals of this study were to (a) understand the silting dynamics inside the inner harbor, (b) identify heavy metals which might be of …

Larval Ecology Of Atlantic Bluefin Tuna (Thunnus Thynnus): New Insights From Otolith Microstructure, Biotic, And Abiotic Analyses From The Gulf Of Mexico And Mediterranean Sea, Estrella Malca

All HCAS Student Capstones, Theses, and Dissertations

Atlantic bluefin tuna (ABT), Thunnus thynnus, spawn in the Gulf of Mexico (GoM) and the Mediterranean Sea (MED). Spawning occurs within narrow temporal and environmental parameters. Efforts to characterize growth of ABT in wild conditions revealed a wide range of growth variability during the early life stages. This series of studies examined potential biotic and abiotic influences of larval growth from seven ABT cohorts, and identified several key drivers of growth for this commercially valuable species. A detailed investigation of larval dynamics using otolith microstructure was conducted as follows. First, companion growth curves and stable isotope analysis from the same …

One Health In Action: Flea Control And Interpretative Education At Badlands National Park, David Eads, Lindsey Buehler, Anne Esbenshade, Jason Fly, Evan Miller, Holly Redmond, Emily Ritter, National Park Service, Sasha Wittmann, Paul Roghair, Eddie Childers

United States Geological Survey: Staff Publications

No abstract provided.

Storm Intensity And Forward Speed Controls On Back-Barrier And Shoreface Sediment Dynamics Along The Louisiana Coast, Md Mohiuddin Sakib

LSU New Orleans Theses and Dissertations

High energetic storms import sediment to back-barrier bays and marshes and produce a perennial footprint that contributes to the long-term evolution of the inner shelf, bays, and marsh platform. The magnitude of sedimentation in back-barrier bays and marshes varies with storm characteristics (e.g., storm intensity, forward speed, size, and track). However, quantifying the impacts of storm characteristics on the sediment exchange between the inner shelf, bays, and marshes and documenting the resulting net sediment import and export patterns across these interfaces remains largely unexplored. Here we applied a calibrated Delft3D hydrodynamics and sediment transport model to a microtidal bay-marsh complex …

Conjunctive Management For Groundwater-Surface Water Resources: Numerical Modeling And Potential Assessment Of Managed Aquifer Recharge (Mar) At Lower Rio Grande Valley In South Texas, Dwight Zedric Q. Capus

Theses and Dissertations

Texas is well known to frequent floods and droughts, and yet has mounting concerns in very imbalanced water availability and water demands from growth in population and economical activities. Capturing and storing water is essential to long-term and climate-smart management of the “already-scarce” water resources. This study aimed to apply numerical modeling to evaluate potentials and impacts of Managed Aquifer Recharge (MAR) to regional groundwater systems in the Lower Rio Grande Valley. Using Visual MODFLOW Flex 3D package, different scenarios were simulated for groundwater flow patterns and storage capacities. Water injections tested ranged between 7.30x105 ft3 to 3.65x109 ft3 , …

Increased Aerosols Can Reverse Twomey Effect In Water Clouds Through Radiative Pathway, Pradeep Khatri, Tadahiro Hayasaka, Brent N. Holben, Ramesh P. Singh, Husi Letu, Sachchida N. Tripathi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aerosols play important roles in modulations of cloud properties and hydrological cycle by decreasing the size of cloud droplets with the increase of aerosols under the condition of fixed liquid water path, which is known as the first aerosol indirect effect or Twomey-effect or microphysical effect. Using high-quality aerosol data from surface observations and statistically decoupling the influence of meteorological factors, we show that highly loaded aerosols can counter this microphysical effect through the radiative effect to result both the decrease and increase of cloud droplet size depending on liquid water path in water clouds. The radiative effect due to …

Comparing Past And Future Drought And Surplus Periods In The Colorado River Basin, Rama Bedri

Student Scholar Symposium Abstracts and Posters

The Colorado River Basin is crucial to the Western United States, providing water for seven states and Mexico. Historical and future periods of drought and surplus are analyzed in 17 Colorado River stations. Unimpaired streamflow data are evaluated from the U.S. Geological Survey, Bureau of Reclamation, and Coupled Modeled Intercomparison Projection 5 from 1950-2099. Future projections are based on eight climate scenarios. Four climate models (HadGEM2-ES, CNRM-CM5, CanESM2, MI-ROC5) are observed at Representative Concentration Pathways (RCP) 4.5 and 8.5 emission scenarios. Furthermore, the ensemble water year means of the four models are analyzed. The durations of drought or surplus, magnitudes, …

Drought‑Stricken U.S. States Have More Comprehensive Water‑Related Hazard Planning, Theresa Jedd, Kelly Smith

National Drought Mitigation Center: Faculty Publications

Despite the devastating impacts of droughts, the United States lacks a national drought plan. This leaves states to address droughts in water, hazard, and stand-alone plans which are designed to reduce drought vulnerability and to prepare government, industry, and society to cope with the impacts. Yet, there is limited empirical research that evaluates the comprehensiveness of these plans, specifically in terms of whether they include preparedness and mitigation measures or triggers for action and response. To fill this gap, this study’s first aim was to establish an evaluation framework based on principles from the drought mitigation literature. The study then …

The Sensitivity Of Meteorological Dynamics To The Variability In Catchment Characteristics, Shimelash Molla Kassaye, Tsegaye Tadesse, Getachew Tegegne, Kindie Engdaw Tadesse

National Drought Mitigation Center: Faculty Publications

Evaluating meteorological dynamics is a challenging task due to the variability in hydroclimatic settings. This study is designed to assess the sensitivity of precipitation and temperature dynamics to catchment variability. The effects of catchment size, land use/cover change, and elevation differences on precipitation and temperature variability were considered to achieve the study objective. The variability in meteorological parameters to the catchment characteristics was determined using the coefficient of variation on the climate data tool (CDT). A land use/cover change and terrain analysis was performed on Google Earth Engine (GEE) and ArcGIS. In addition, a correlation analysis was performed to identify …

Do Pharmaceuticals In The Environment Pose A Risk To Wildlife?, Thomas G. Bean, Elizabeth A. Chadwick, Marta Herrero‐Villar, Rafael Mateo, Vinny Naidoo, Barnett A. Rattner

United States Geological Survey: Staff Publications

The vast majority of knowledge related to the question “To what extent do pharmaceuticals in the environment pose a risk to wildlife?” stems from the Asian vulture crisis (>99% decline of some species of Old World vultures on the Indian subcontinent related to the veterinary use of the nonsteroidal anti‐inflammatory drug [NSAID] diclofenac). The hazard of diclofenac and other NSAIDs (carprofen, flunixin, ketoprofen, nimesulide, phenylbutazone) to vultures and other avian species has since been demonstrated; indeed, only meloxicam and tolfenamic acid have been found to be vulture‐safe. Since diclofenac was approved for veterinary use in Spain and Italy in …

A 14,100 Cal B. P. Rocky Mountain Locust Cache From Winnemucca Lake, Pershing County, Nevada, Evan J. Pellegrini, Eugene M. Hattori, Larry Benson, John Southon, Hojun Song, Derek A. Woller

United States Geological Survey: Staff Publications

The remains of approximately 1000 (MNI) Rocky Mountain locusts (Melanoplus spretus) from an archaeological cache pit in Crypt Cave, Winnemucca (dry) Lake, Nevada, date to between 14,305–14,067 calendar years before present (95.4 % confidence; 12,238 ± 18 ¹⁴C yrs. B.P.). The age of this western Great Basin occupation along the shoreline of Lake Lahontan is consistent with occupation of several other Western North American terminal Pleistocene sites dating prior to 14,000 cal. B.P., including distinctive petroglyphs on the western shore of Winnemucca Lake dating as early as 14,800–13,200 cal. B.P.

Comparative Behavioral Ecotoxicology Of Inland Silverside Larvae Exposed To Pyrethroids Across A Salinity Gradient, Sara J. Hutton, Samreen Siddiqui, Emily I. Pedersen, Christopher Y. Markgraf, Amelie Segarra, Michelle L. Hladik, Richard E. Connon, Susanne M. Brander

United States Geological Survey: Staff Publications

Pyrethroids, a class of commonly used insecticides, are frequently detected in aquatic environments, including estuaries. The influence that salinity has on organism physiology and the partitioning of hydrophobic chemicals, such as pyrethroids, has driven interest in how toxicity changes in saltwater compared to freshwater. Early life exposures in fish to pyrethroids cause toxicity at environmentally relevant concentrations, which can alter behavior. Behavior is a highly sensitive endpoint that influences overall organism fitness and can be used to detect toxicity of environmentally relevant concentrations of aquatic pollutants. Inland Silversides (Menidia beryllina), a commonly used euryhaline model fish species, were exposed …

Population Health Metrics During The Early Stages Of The Covid-19 Pandemic: Correlative Pilot Study, Marie A. Severson, David A. Cassada, Victor C. Huber, Daniel D. Snow, Lisa M. Mcfadden

Nebraska Water Center: Faculty Publications

Background: COVID-19 has caused nearly 1 million deaths in the United States, not to mention job losses, business and school closures, stay-at-home orders, and mask mandates. Many people have suffered increased anxiety and depression since the pandemic began. Not only have mental health symptoms become more prevalent, but alcohol consumption has also increased during this time. Helplines offer important insight into both physical and mental wellness of a population by offering immediate, anonymous, cheap, and accessible resources for health and substance use disorders (SUD) that was unobstructed by many of the mandates of the pandemic. Further, the pandemic also …

Using Active Source Seismology To Image The Palos Verdes Fault Damage Zone As A Function Of Distance, Depth, And Geology, Travis Alongi, Emily E. Brodsky, Jared Kluesner, Daniel Brothers

United States Geological Survey: Staff Publications

Fault damage zones provide a window into the non-elastic processes of an earthquake. Geological and seismic tomography methods have been unable to measure damage zones at depth with sufficient spatial sampling to evaluate the relative influence of depth, distance, and lithological variations. Here, we identify and analyze the damage zone of the Palos Verdes Fault offshore southern California using two 3D seismic reflection datasets. We apply a novel algorithm to identify discontinuities attributed to faults and fractures in large seismic volumes and examine the spatial distribution of fault damage in sedimentary rock surrounding the Palos Verdes Fault. Our results show …

Coastal Wetland Area Change For Two Freshwater Diversions In The Mississippi River Delta, John R. White, Brady Couvillion, John W. Day

United States Geological Survey: Staff Publications

Coastal systems around the globe are being re-integrated with adjacent river systems to restore the natural hydrologic connection to riparian wetlands. The Mississippi River sediment diversions or river reconnections are one such tool to combat high rates of wetland loss in coastal Louisiana, USA by providing freshwater, sediment, and nutrients. There has been some disagreement in the published literature whether re-establishing river reconnection is slowing or contributing to coastal wetland loss. This issue is due to the difficulties in the application of remote sensing in low-relief environments where water level changes could indicate either land loss or simply temporary submergence. …

Evidence For The ~ 1.4 Ga Picuris Orogeny In The Central Colorado Front Range, Asha A. Mahatma, Yvette D. Kuiper, Christopher S. Holm-Denoma

United States Geological Survey: Staff Publications

We present the first evidence for sedimentation and new evidence for penetrative deformation and metamorphism in the central Colorado Front Range associated with the ~ 1.48–1.35 Ga Picuris orogeny. This orogeny has recently been recognized in New Mexico, Arizona and southern Colorado and may be part of a larger active accretionary margin that includes the ~ 1.51–1.46 Ga Pinware and Baraboo events, in eastern Canada and central US respectively, that preceded the amalgamation of the Rodinian supercontinent. We demonstrate that in addition to ~ 1.4 Ga reactivation of northeast-trending Paleoproterozoic shear zones, regional folding occurred in an area south of …

Level And Pattern Of Overstory Retention Shape The Abundance And Long-Term Dynamics Of Natural And Created Snags, Charles B. Halpern, Allison K. Rossman, Joan C. Hagar

United States Geological Survey: Staff Publications

Standing dead trees, or snags, serve myriad functions in natural forests, but are often scarce in forests managed for timber production. Variable retention (VR), the retention of live and dead trees through harvest, has been adopted globally as a less intensive form of regeneration harvest. In this study, we explore how two key elements of VR systems — level (amount) and spatial pattern of live-tree retention — affect the carryover and post-harvest dynamics of natural and artificially created snags. We present nearly two decades of data from the DEMO Study, a regional-scale experiment in VR harvests of Douglas-fir-dominated forests in …

Airflow Dynamics In Wind Cave And Jewel Cave: How Do Barometric Caves Breathe?, Annika K. Gomell, Andreas Pflitsch

International Journal of Speleology

Recent research on air pressure propagation through barometric caves has revealed various speleoclimatological processes, which cause a more complex relationship between surface air pressure changes and resulting pressure gradients between cave and surface air than previously assumed. So far, however, studies on barometric cave airflow have only been based on surface air pressure measurements. Thus, this study investigates and compares airflow at the openings of Wind Cave and Jewel Cave – two major barometric cave systems in South Dakota, USA – as a response to surface air pressure changes and air pressure gradients. Based on high-resolution long-term air pressure measurements …

Hydrogen Isotope Behavior During Rhyolite Glass Hydration Under Hydrothermal Conditions, Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern

United States Geological Survey: Staff Publications

The diffusion of molecular water (H₂O_m) from the environment into volcanic glass can hydrate the glass up to several wt% at low temperature over long timescales. During this process, the water imprints its hydrogen isotope composition (δD_H2O) to the glass (δD_gl) offset by a glass-H₂O fractionation factor (ΔD_gl-H2O = δD_gl – δD_H2O) which is approximately -33‰ at Earth surface temperatures. Glasses hydrate much more rapidly at higher, sub-magmatic temperatures as they interact with H₂O during eruption, transport, and emplacement. To aid in the interpretation …

Droughtscape, Fall 2022, National Drought Mitigation Center

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

DroughtScape, Fall 2022

Evaluating The Impact Of Submarine Groundwater Discharge On Nutrients And Trace Elements In Coastal Systems: The Examples Of The Tuckean Swamp (Australia) And The Mississippi Sound (Usa), Amy Moody

Dissertations

Submarine groundwater discharge (SGD) is the advective flow of both fresh terrestrial groundwater and recirculating seawater through aquifer sediments, which is released into the coastal ocean. In this dissertation, I evaluated the impact of SGD on the distributions and input of trace metals and nutrients. In the Tuckean Swamp, an estuary in Australia dominated by coastal acid sulfate soils, I determined the impact of groundwater on Ba and U during the flood season, when the local aquifer is flushed out after a rapid increase in water table elevation. For Ba and U, groundwater contributed up to 18 and 66 % …

Getting Ahead Of Flash Drought: From Early Warning To Early Action, Jason A. Otkin, Molly Woloszyn, Hailan Wang, Mark D. Svoboda, Marina Skumanich, Roger Pulwarty, Joel Lisonbee, Andrew Hoell, Mike Hobbins, Tonya Haigh, Amanda E. Cravens

National Drought Mitigation Center: Faculty Publications

Flash droughts, characterized by their unusually rapid intensification, have garnered increasing attention within the weather, climate, agriculture, and ecological communities in recent years due to their large environmental and socioeconomic impacts. Because flash droughts intensify quickly, they require different early warning capabilities and management approaches than are typically used for slower-developing “conventional” droughts. In this essay, we describe an integrated research-and-applications agenda that emphasizes the need to reconceptualize our understanding of flash drought within existing drought early warning systems by focusing on opportunities to improve monitoring and prediction. We illustrate the need for engagement among physical scientists, social scientists, operational …

Regenerative Agriculture Framework For Island Ecosystems Using São Miguel As A Case Study, Mya Hunter

Independent Study Project (ISP) Collection

Context: Regenerative agriculture is a farming approach that uses soil health as the entry point to contribute to multiple objectives, such as improved nutrient cycling and climate regulation. Farmers can apply different practices to reach these objectives. The objectives and practices, however, are not equally relevant or applicable for farming systems on island ecosystems and the local context.

Objectives: The main objective of this paper, therefore, is to find out how solutions towards regenerative agriculture can be identified and evaluated as such that they result in meaningful advice for farmers on island ecosystems in order to mitigate the …

Investigating Primary Succession Following The Retreat Of The Breiðamerkurjökull Glacier, Iceland, Ella Roelofs

Independent Study Project (ISP) Collection

The accelerating rates of glacier retreat around the world as a result of climate change make the study of primary succession in expanding forefields increasingly important. While this is a well studied topic in many parts of the world, little data exists specific to Iceland. This study investigated vegetation development along a chronosequence of eight time periods in the Breiðamerkurjökull outwash plain. Data was collected on percent vegetation cover, dominant species, the number of unique plant groups, and percent cover of five substrate types at 10 plots (0.55 x 0.55 m quadrats) per time period. Important findings include the fact …

Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening

Independent Study Project (ISP) Collection

As mangrove forests are destroyed by human factors across the earth, many crucial ecological processes that take place in these systems of trees are obstructed. One of the most important roles played by mangroves is their ability to sequester carbon in the sediment, as this storage of carbon helps diminish atmospheric warming. Many sediment microorganisms help in this process of carbon sequestration and play various other vital roles in mangrove ecosystems. Microorganisms in marine sediments can be used to assess the health of the surrounding environment. Past research has found significant differences in sediment microorganism composition, abundance, and diversity in …

Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner

United States Geological Survey: Staff Publications

In many countries the use of lead-based ammunition is prevalent, and results in exposure and poisoning of waterfowl and other species of birds. In waterfowl hunting areas large quantities of spent shot may be deposited in wetland and terrestrial habitats. These pellets can undergo transformations, which are influenced by various abiotic and biotic factors. In addition to lead (Pb), other elements like antimony (Sb) and arsenic (As) can be leached from Pb shot into the environment. In vitro simulations that included organic matter and microorganisms were utilized to examine elemental leaching from gunshot. We found that leaching efficiency was the …

Limits To Coseismic Landslides Triggered By Cascadia Subduction Zone Earthquakes, Alex R.R. Grant, William T. Struble, Sean R. Lahusen

United States Geological Survey: Staff Publications

Landslides are a significant hazard and dominant feature throughout the landscape of the Pacific Northwest. However, the hazard and risk posed by coseismic landslides triggered by great Cascadia Subduction Zone (CSZ) earthquakes is highly uncertain due to a lack of local and global data. Despite a wealth of other geologic evidence for past earthquakes on the Cascadia Subduction Zone, no landslides have been definitively linked to such earthquakes, even in areas otherwise highly susceptible to failure. While shallow landslides may not leave a lasting topographical signature in the landscape, there are thousands of deep-seated landslides in Cascadia, and these deposits …

Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V. V. Vesselinov, B. Ahmmed, M. K. Mudunuru, J. D. Pepin, E. R. Burns, D. L. Siler, S. Karra, R. S. Middleton

United States Geological Survey: Staff Publications

Discovery of hidden geothermal resources is challenging. It requires the mining of large datasets with diverse data attributes representing subsurface hydrogeological and geothermal conditions. The commonly used play fairway analysis approach typically incorporates subject-matter expertise to analyze regional data to estimate geothermal characteristics and favorability. We demonstrate an alternative approach based on machine learning (ML) to process a geothermal dataset from southwest New Mexico (SWNM). The study region includes low- and medium-temperature hydrothermal systems. Several of these systems are not well characterized because of insufficient existing data and limited past explorative work. This study discovers hidden patterns and relations in …