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Sediment And Debris Flows Resulting From The 2020 El Dorado Wildfire, San Bernardino Mountains, California, Andrew Suarez

Electronic Theses, Projects, and Dissertations

The Yucaipa Ridge is a section of the San Bernardino Mountains within the Transverse Ranges of Southern California. During the summer and early fall of 2020, Yucaipa Ridge experienced severe vegetation damage from both the Apple and El Dorado wildfires. Burned slopes exhibit a higher susceptibility to geomorphic change within several years of burning from the introduction of meteoric water onto the slope. Yucaipa, Oak Glen, and other nearby communities are currently at risk of damage by hyperconcentrated flows and debris flows during the seasonal rainy season.

Debris flows and hyperconcentrated flows (a.k.a. mudflows; are grouped and referred to in …

Post-Fire Debris Flow Initiation Potential Based On Forensic Analysis Of Debris Flow Occurrence From The 2020 El Dorado Wildfire On Yucaipa Ridge, San Bernardino County California, Seth Clemen D. Saludez

Electronic Theses, Projects, and Dissertations

This study focuses on the potential debris flow initiation and effect in areas affected by the El Dorado Fire in the Southern San Bernardino Mountains. It uses novel technology combining drone-based photography and LiDAR imaging to create surface models of areas where potential debris flows could initiate, flow, and be deposited. The scans were repeated as geomorphic change occurred through the wet season to document spatial and volumetric changes resulted from the flows. These measurements were combined with traditional fire assessment and observational methods to characterize pertinent conditions.

As we investigated potential debris flow risk in this study area, we …

The Human Legacy: Agriculture, Civilizations, Strife, And Pandemics Changing Our Climate, Jacalyn M. Wittmer Malinowski

Climate Change and the Individual, 2025-26

For most of human history, climate has shaped our lives, while our influence on it remained minimal. However, the notion that early humans had no measurable impact on the climate before industrialization is inaccurate. Early in human history, activities – such as the rise of agriculture, the growth of civilizations, periods of conflict, and pandemics – altered greenhouse gas levels in the atmosphere. These changes contributed to significant periods of climate change long before the burning of fossil fuels set us on the path to today’s global climate crisis.

From The Ground Up: Community-Based Participatory Research Reclaiming The Science Of Lead, Juan Manuel Rubio, Bavisha Kaylan, Anthony Diaz, Patricia Flores, Maya Cheav, David C. Bañuelas, Ashley Green, Annika Hjelmstad, Ariane Jong-Levinger, Tim Schütz, Maya Carrasquillo, Alana M. W. Lebron, Jun Wu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

For decades, the dominant approach to lead poisoning has been to focus on homes affected by lead paint and to treat children who are already suffering from lead poisoning. This individualizing approach developed in the context of the defunding and deregulation of government agencies in the 1980s. In recent years, however, community–academic partnerships have reframed lead as an environmental issue produced by the development of the lead industry in the twentieth century and connected to overlapping histories of exploitation, discrimination, and inaction. These community-based projects have contributed to shifting research agendas (by emphasizing historical analysis and the study of the …

Inferences Of Source Lithologies For Chicxulub Microtektites Using A Bayesian Approach, Jack Carter, Paolo Sanchez, Anthony J. Fuentes, Paul R. Renne, Dale H. Burns, Hermann D. Bermúdez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Chicxulub impact on the Yucatán Peninsula at the Cretaceous-Paleogene boundary (KPB) was a likely contributor to the end-Cretaceous mass extinction. Glassy objects produced by quenched melt from the impact were distributed over a large region centered on the Caribbean basin and have long been known to preserve compositional information that could allow for more robust constraints on the pre-impact target lithologies. The Chicxulub-derived glasses are generally altered in most localities, but a recently discovered deposit at Gorgonilla Island, Colombia, yields a large percentage of unaltered glassy microtektites up to ∼2 mm (There is inconsistent usage of these terms in …

Meeting Carbon Dioxide Removal Demand In 2030: The Potential Of Macroalgae Cultivation And Harvest, Lotta Siebert, Jiajun Wu, Lena-Katharina Bednarz, David Keller, Felix Meier, Christine Merk, Sonja Peterson, Wilfried Rickels

Journal of Ocean and Coastal Economics

A growing number of countries have announced net-zero and net-negative emissions targets, but only a few countries provide incentives for carbon dioxide removal (CDR). We derive estimates of countries' hypothetical demand for CDR in 2030 based on their emissions reduction targets under the Paris Agreement. The aggregated average global demand for CDR in the compliance year 2030 is 1064 MtCO₂, 353 MtCO₂, and 124 MtCO₂ for the low, medium, and high-cost CDR scenarios, respectively. This demand comes exclusively from countries and regions with relatively high GDP per capita, relatively high abatement costs and a limited …

The Sedimentological Signature Of Impact Spherules And Its Relation To Ejecta Transport Mechanisms During The Chicxulub Asteroid Impact (Cretaceous/Paleogene Boundary), Hermann D. Bermúdez, Liliana Bolívar, José A. Arz, Ignacio Arenillas, Vicente Gilabert, Robert Depalma, George Phillips, Daniela Bermúdez, Maurizia De Palma, Clemencia Gómez, Ying Cui

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Chicxulub impact is the most likely cause of the Cretaceous/Paleogene boundary (KPB) mass extinction and the only impact event in Earth's history with a globally traceable ejecta bed. Although the impact spherules are thought to represent molten or vaporized material, precise genesis and transport mechanisms remain underconstrained. Here, we show that the morphology, size, internal structure, and distribution of the spherules within the KPB deposits are related to origin and transport processes. The study of thousands of spherules from KPB deposits in Colombia, the USA, and Spain has revealed the presence of three fractions related to three different distribution …

Caves, Calculus, And Climate Change: Measuring And Modeling The Discharge Of Biz Falls In Mammoth Cave National Park, Ava Lich

Mahurin Honors College Capstone Experience/Thesis Projects

Climate change poses a significant global challenge, with increasing levels of atmospheric carbon dioxide as a primary driver of rising temperatures and environmental disruptions. Karst systems, such as those in South-Central Kentucky, play a role in sequestering atmospheric CO₂ through the dissolution of limestone, a process that forms unique landscapes while mitigating climate impacts. This study investigates the discharge dynamics of Cascade River in Great Onyx Cave to enhance understanding of the relationship between hydrology and carbon sequestration in karst environments. A barrel weir equipped with pressure transducers was employed to collect and measure water flow, and Torricelli’s law was …

Data For Research Collaboration And Co-Authorship In The Gulf Of Mexico, 2000–2018, Owen Temby, Dongkyu Kim, Juliet Vallejo

Datasets

This dataset documents research collaboration and co-authorship among organizations engaged in environmental science in the Gulf of Mexico from 2000 to 2018. The data were compiled through bibliometric analysis of scientific articles, with each record containing publication-level and author affiliation information, as well as institutional and country codes. The dataset provides the basis for network analysis of collaborative patterns among institutions in the United States, Mexico, and Cuba. Variable definitions and data structure are described in the accompanying README file.

Geological And Environmental Sciences - 2025, Dept. Of Geological And Environmental Sciences

Geological and Environmental Sciences News

• Greetings from the Department Chair
• Faculty Updates
• 2025 Geological and Environmental Sciences Department Alumni Achievement Awardee Mr. Thomas Hanna
• 60 Years - Telling Our Story
• Empowering the next generation of geoscientists

Applying Transfer Learning For Street-Scale Nuisance Flood Forecasting In Coastal-Urban Cities, Binata Roy, Jonathan L. Goodall, Diana Mcspadden, Chetan Kumar, Steven Goldenberg, Yidi Wang, Malachi Schram

VMASC Publications

An important challenge with Machine Learning (ML) is its transferability; i.e., whether a ML model trained on one set of data can be applied to a second set of data without requiring full re-training of the model. Transfer Learning (TL) addresses this challenge by transferring knowledge learned in the source domain (the data it was trained on) to the target domain (a second set of data that is statistically different but related, which the model was not trained on). This study investigates the use of TL for street-scale nuisance flood forecasting by exploring whether a ML model trained for one …

A Unionid Mussel Biodiversity Hotspot Experiencing Unexplained Declines: Evaluating The Influence Of Chemical Stressors Using Caged Juveniles, W. Aaron Wilson, Christine Bergeron, Jennifer Archambault, Jason M. Unrine, Jess Jones, Braven Beaty, Damian Shea, Peter R. Lazaro, Jody L. Callihan, Jennifer J. Rogers

Plant and Soil Sciences Faculty Publications

Unionid mussel populations in a section of the Clinch River in Virginia, USA, has declined substantially, but the causes of the decline remain unknown. To investigate this zone of decline (ZOD), we deployed juvenile freshwater mussels (Villosa iris in 2012 and Lampsilis fasciola in 2013) in both cages and silos at sites within the Clinch River System. We analyzed mussel tissues for trace element and organic contaminant concentrations, shells for trace elements, and environmental media (total water, dissolved water, particulate sediment, and bedload sediment) for both inorganic and organic contaminants. We found a few differences between mussels deployed in cages …

Integrating Satellite-Based Precipitation Analysis: A Case Study In Norfolk, Virginia, Imiya M. Chathuranika, Dalya Ismael

Engineering Technology Faculty Publications

In many developing cities, the scarcity of adequate observed precipitation stations, due to constraints such as limited space, urban growth, and maintenance challenges, compromises data reliability. This study explores the use of satellite-based precipitation products (SbPPs) as a solution to supplement missing data over the long term, thereby enabling more accurate environmental analysis and decision-making. Specifically, the effectiveness of SbPPs in Norfolk, Virginia, is assessed by comparing them with observed precipitation data from Norfolk International Airport (NIA) using common bias adjustment methods. The study applies three different methods to correct biases caused by sensor limitations and calibration discrepancies and then …

The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming

Antioch University Dissertations & Theses

Wood turtles occupy cold, low-gradient riverine habitat throughout the northeastern United State and southeastern Canada. Stream alterations, such as dams, channel straightening, and floodplain development have diminished the natural hydrologic and sedimentation regimes that result in complex channel and floodplain geomorphology. Studies throughout the species’ range have quantified many aspects of their habitat, but none have quantified components of geomorphology of wood turtle sites. The goal of this study was to explore the role of stream channel and floodplain geomorphology in wood turtle habitat use, with specific objectives to (1) quantify components of stream channel and floodplain geomorphic complexity, (2) …

When Emotions Flare: Solar Rhythms, Emotions And Cycles Of Political Revolution, Andreas Hernandez, Carolina Zilli Vieira, Alexandra Smith, Rebecca Olson

Geography and Environmental Studies Faculty Publications

Revolutions are among the most transformative events in human history. Analyzing 395 revolutionary episodes from 1900 to 2014, we find that major waves cluster around solar maxima - periods of intensified geomagnetic activity. Drawing on biomedical research linking geomagnetic disturbances to cardiovascular and stress regulation, and thus to emotional states, we propose that solar cycles modulate the affective ecologies within which revolutions arise. Solar activity may accelerate, shape, and amplify revolutionary cycles by heightening emotional climates and tipping fragile systems toward mass mobilization. This reframes revolutions as planetary events - entanglements of political conflict, embodied emotion, and cosmic …

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Controls Of Wetland Hydrology In The Zone Of Discontinuous Permafrost, Northwest Territories, Canada, Iain Thomson

Theses and Dissertations (Comprehensive)

Mean annual air temperatures are increasing rapidly in northwestern Canada, which is among the most rapidly warming regions on Earth (Box et al., 2019). Consequently, permafrost thaw within northwestern Canada is proceeding at a rate not found in the historical record (Pelletier et al., 2017), with areal thaw rates especially high in the peatland-dominated southern margin of discontinuous permafrost (Quinton et al., 2019). Permafrost thaw has caused vast land cover changes and transformed the permafrost underlain forest into permafrost free wetlands over much of Taiga Plains (Carpino et al., 2018; Jorgenson & Osterkamp, 2005). This land cover change has …

Unfolding Cascading Impacts Of Changing South Asia Monsoon On A Hindu Kush Himalayas Basin, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Arshad Ansari, Suraj Tiwari, Roma Thakurathi, Rejoice Thomas, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Study region

Study focus

New hydrological insights for the region

Predicted Water Yield Of Open-Pit Metal Mines Based On A Bi-Rnn And Gms Coupling Model, Zhao Yuxing, Li Xiangwen

Coal Geology & Exploration

Objective Accurately predicting water yield of mine before mining can provide directive guidance for preventing potential water hazards and ensuring safe production. Methods To enhance the prediction accuracy and stability of water yield of open-pit metal mines, for which atmospheric precipitation acts as the primary recharge source of water, this study developed a prediction model that coupled a bidirectional recurrent neural network (Bi-RNN) and the Groundwater Modeling System (GMS) software. Specifically, based on historical forecasted precipitation data provided by the Global Forecast System (GFS), the fluctuation pattern of differences between predicted forecasted and actual precipitation was analyzed. After being corrected …

Estimating Medium-Term Regional Monthly Economic Activity Reductions During The Covid-19 Pandemic Using Nighttime Light Data, Ma Flordeliza P. Del Castillo, Toshio Fujimi, Hirokazu Tatano

SOSE Affiliate: Manila Observatory

Economic impact estimates of the initial lockdowns due to the COVID-19 pandemic showed a significant reduction in economic activities globally. However, the succeeding impacts and their spatiotemporal distribution within countries remain unknown. Studies showed that nighttime light data (NTL) has effectively revealed the spatiotemporal dimensions of the economic effects of COVID-19. Thus, this study used NTL data to determine the medium-term regional monthly economic impacts of the pandemic in the Philippines in terms of the Economic Activity Reduction (EAR) index. We generated a spatial error model, regressing pre-pandemic NTL on mean temperature, maximum rainfall, and built-up area. This model explained …

Net Evaporation-Induced Mangrove Area Loss Across Low-Lying Caribbean Islands, Isamar M. Cortés, Jorge Lorenzo-Trueba, Andre S. Rovai, Robert R. Twilley, Mark Chopping, Temilola Fatoyinbo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Although mangroves provide many beneficial ecosystem services, such as blue carbon storage and coastal protection, they are currently under threat due to changes in climate conditions, such as prolonged drought exposure. Under drought conditions, evaporation exceeds precipitation and high soil salinities can lead to stunted growth and die-back. To quantify this interplay, we developed a database for low-lying and uninhabited mangrove islands in the Caribbean under various evaporation and precipitation regimes. We extracted physical and biological information from each island using remote sensing techniques and coupled it with a process-based model. We used this database to develop a model that …

State Of The Art And Future Directions In Groundwater Contamination Risk Assessment, Xu Beiyi, Wang Ce, Zhou Guangyang, Zhou Pengpeng

Coal Geology & Exploration

Background Rapid global socio-economic development has intensified the resource crisis and contamination of groundwater, rendering groundwater contamination risk assessments critical to contamination prevention, control, and remediation. Advances Through a systematic summary of domestic and international studies, this study reviews the development of theories on groundwater contamination risk assessments and the formation of the theoretical system. Based on the source-pathway-receptor assessment system, this study presents a summary of the research methods for the assessments of contamination source load risks, groundwater vulnerability, and contamination hazards. Groundwater contamination risk assessments have evolved from unidimensional qualitative assessments to quantitative process models highlighting contamination mechanisms …

Emerging Consensus On Net Energy Paves The Way For Improved Integrated Assessment Modeling, Louis Delannoy, Matthieu Auzanneau, Baptiste Andrieu, Olivier Vidal, Pierre -Yves Longaretti, Emmanuel Prados, David J. Murphy, Roger W. Bentley, Michael Carbajales- Dale, Marco Raugei, Mikael Ho¨O¨K, Victor Court, Carey W. King, Florian Fizaine, Pierre Jacques, Matthew Kuperus Heun, Andrew Jackson, Charles Guay- Boutet, Emmanuel Aramendia, Jianliang Wang, Hugo Le Boulzec, Charles A.S. Hal

University Faculty Publications and Creative Works

Extracting, processing, and delivering energy requires energy itself, which reduces the net energy available to society and yields considerable socioeconomic implications. Yet, most mitigation pathways and transition models overlook net energy feedbacks, specifically related to the decline in the quality of fossil fuel deposits, as well as energy requirements of the energy transition. Here, we summarize our position across 8 key points that converge to form a prevailing understanding regarding EROI (Energy Return on Investment), identify areas of investigation for the Net Energy Analysis community, discuss the consequences of net energy in the context of the energy transition, and underline …

Sea Surface Temperatures, The Gulf Of Mexico Loop Current, Hurricane Ian, And Their Junction, Alexander K. Nickerson

USF Tampa Graduate Theses and Dissertations

In the first chapter, a climatology was created for the deep Gulf of Mexico, West Florida Shelf, and Tampa Bay. These climatologies were compared to each other and to global temperatures. Seasonal variability is shown to be a product of bathymetry as well as latitude. In Chapter Two, using the self-organizing map neural network, patterns of the Gulf of Mexico Loop Current were analyzed to establish phases with necessary and sufficient conditions for translation from one phase to the next. Two separate patterns of evolution were established from these analyses, and empirical arguments are used to confirm the findings from …

Scientific History, Sampling Approach, And Physical Characterization Of The Camp Century Subglacial Material, A Rare Archive From Beneath The Greenland Ice Sheet, Paul R. Bierman, Andrew J. Christ, Catherine M. Collins, Halley M. Mastro, Juliana Souza, Pierre Henri Blard, Stefanie Brachfeld, Zoe R. Courville, Tammy M. Rittenour, Elizabeth K. Thomas, Jean Louis Tison, François Fripiat

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Basal materials in ice cores hold information about paleoclimate conditions, glacial processes, and the timing of past ice-free intervals, all of which aid understanding of ice sheet stability and its contribution to sea level rise in a warming climate. Only a few cores have been drilled through ice sheets into the underlying sediment and bedrock, producing limited material for analysis. The last of three Camp Century ice cores, which the U.S. Army collected in northwestern Greenland from 1963-1966 CE, recovered about 3.5 m of subglacial material, including ice and sediment. Here, we document the scientific history of the Camp Century …

Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …

Groundwater Modeling Of The Ogallala Aquifer: Use Of Machine Learning For Model Parameterization And Sustainability Assessment, Tewodros Aboret Tilahun

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Addressing groundwater depletion problems in heterogeneous aquifer systems is a challenge. The heterogeneous Ogallala Aquifer, a critical source of groundwater in the central United States, has undergone decades of decline in water levels due to pumping. This project aims to build a robust groundwater model to evaluate optimal scenarios for sustainable use of the groundwater resource within a section of the Ogallala aquifer located in the Middle Republican Natural Resources District (MRNRD). This study follows a comprehensive approach involving parameterization, construction, and optimization. The model is parametrized using hydraulic conductivity and recharge values obtained from a random forest-based machine learning …

Transferred Benefits In Inter-Community Beach Nourishment: A Field Study On Efficiency, Owen Thomas

Theses, Dissertations and Culminating Projects

To combat the effects of relative sea level rise and the natural erosional processes affecting the sandy, diffusive beaches of New Jersey, most communities utilize beach nourishment to stabilize their beaches. Beach nourishment, the practice of artificially widening the beach berm with sand from other areas, not only stabilizes beaches but also protects oceanfront homes from storm surges, while adding recreational space and tourism value. These benefits are reflected in increased property values, most notably in oceanfront properties. The diffusive nature of these beaches, however, means that individual nourishment events are inherently shared with neighboring communities as sand is readily …

Onset Of Antarctic Glaciation At The Eocene-Oligocene Transition In The Weddell Sea And Its Impact On Ocean Circulation, Victoria Hojnacki

Theses, Dissertations and Culminating Projects

The Eocene – Oligocene Transition (EOT) (34 Ma) represents a greenhouse to icehouse climate transition that is marked by the appearance of permanent ice sheets in Antarctica. Studying this period of climate change allows us to understand how different Earth systems reacted under changing atmospheric CO₂ conditions. Though the timing of the development of the East Antarctic Ice Sheet is well supported, the development of the West Antarctic Ice Sheet is still up for debate. Ocean Drilling Program Site 696 is the only paleoarchive of the EOT in the Weddell Sea region and offers an opportunity to better constrain the …

A Geochemical Mechanism For >10 M Apparent Downward Offsets Of Magnetic Reversals Inferred From Comparison Of Two Scotia Sea Drill Sites, Brendan T. Reilly, Lisa Tauxe, Stefanie A. Brachfeld, Bridget Kenlee, Marcus Gutjahr, Andrew W. Dale, Iván Hernández-Almeida, Sidney Hemming, Ian Bailey, Xufeng Zheng, Daven Cheu, Reece Taglienti, Michael E. Weber, Maureen E. Raymo, Trevor Williams

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

We document an apparent downward displacement of the Matuyama-Brunhes magnetic reversal by ∼20 m at Scotia Sea International Ocean Discovery Program Site U1538 (Pirie Basin) by comparison with the well-defined paleomagnetic record at nearby Site U1537 (Dove Basin). Detailed stratigraphic correlation between the two sites is possible due to similar lithologic variations. However, the two sites have distinctly different porewater geochemistry. Notably, Site U1538 indicates a greater demand for electron acceptors to oxidize organic carbon and Fe²⁺ enrichment below the depth of SO4²⁻ depletion. Magnetic parameters indicate enrichment of an authigenic magnetic mineral with strong remanence properties around …