Hydrology Commons^™

Pre-Calibration Of Δ18O For Paleoclimatic Interpretations Using Stalagmites In Cueva Ensueño, Puerto Rico, Gabriel Enrique López Borobia, Ny Riavo G. Voarintsoa, Ricardo Sánchez-Murillo, Pablo Antonio Llerandi Román

International Journal of Speleology

Stalagmites are invaluable archivers of past climate conditions, as their oxygen isotopic composition (δ¹⁸O_c) closely mirrors the isotopic signature of the drip water (δ¹⁸O_w) from which they precipitate. This isotopic relationship is governed by the fractionation factor (1000ln¹⁸α), which is temperature dependent. In this research, we studied 1000ln¹⁸α within Cueva Ensueño, a cave situated in Puerto Rico’s northern karst region, as a step toward calibrating δ¹⁸O_c for paleoclimate interpretations using stalagmites. We collected drip waters, measured their temperature in situ, and sampled carbonates from ten selected stations within the cave. Sampling was conducted in December …

A Better Great Plains: Bridging The Implementation Gap For A Better Future, David W. Sandahl

School of Natural Resources: Dissertations, Theses, and Student Research

The Northern Great Plains is experiencing extensive native grassland loss and landscape degradation, jeopardizing both ecological integrity and the socio-economic systems that rely upon these ecosystems. In an early effort to lessen degradation, the United States Department of Agriculture (USDA) introduced the Conservation Reserve Program (CRP) which generated ecosystem services benefits such as reduced soil erosion, improved water quality, and increased species diversity through the retirement of cropland and rangeland for 10- or 15-year contracts. However, CRP has not fully modernized alongside today’s agriculturalists and adoption remains shaped by an historically fraught socio-political context characterized by deep-seated mistrust between ranchers, …

Stream Temperature Responses To Summer Urban Rain Events Along The Savannah River, Joseph E. Wermter, Vivian L. Turner, Max K. Appelbaum, James M. Shepherd, Jacob Z. Lott

Journal of South Carolina Water Resources

The hydrological urban heat island (HUHI) is a recent facet of the urban heat island (UHI), describing thermal enhancement of bodies of water in response to urbanization. Although the forefront of this work has been studied for large Metropolitan areas, this effect on developing cities is currently unknown. To locally measure and quantify HUHI effects in a developing city, we utilized Multi-Radar Multi Sensor (MRMS) radar-derived rainfall data to estimate rainfall in the Augusta Metropolitan Area (AMA) and the Savannah Metropolitan Area (SMA), two developing communities adjacent to the Savannah River. We analyzed mean temperature trends of two stream gauges …

New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As precipitation infiltrates into soils, it can recharge them, displace previously stored waters, or bypass already-filled pores. Using 3,697 δ2H and δ18O measurements of water collected nearly monthly over >3 years in 47 forest plots across Switzerland, we present a systematic investigation of the controls on mobile soil water transport. We quantified the lags and damping of water as it percolates downward using young water fraction analysis (Fyw), and the fractions of soil water composed by precipitation that fell within the previous month (new water fractions, Fnew). The Fnew of water sampled in surface soils ranged …

The Future Intensification Of Hydrological Extremes And Whiplashes In The Contiguous United States Increase Community Vulnerability, Surendra Maharjan, Wenzhao Li, John D. Bolten, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydroclimatic whiplash rapid shifts between drought and flood poses growing risks to U.S. communities. Here, we assess historical extremes and future projections using a normalized streamflow metric: the annual mean flow’s deviation from the 1981–2020 average, expressed as a fraction of that average. This metric is applied to United States Geological Survey records and Localized Constructed Analogs downscaled projections under Representative Concentration Pathways 4.5 and 8.5. Results reveal sharp regional disparities, with drought deficits exceeding 300% of normal flow during multi-year droughts. By linking hydrologic outcomes with the Federal Emergency Management Agency’s National Risk Index, we find that counties facing …

Performance Mapping And Weighting For The Evapotranspiration Models Of The Openet Ensemble, M. Reitz, J. M. Volk, T. Ott, M. Anderson, G. B. Senay, F. Melton, A. Kilic, R. Allen, Joshua B. Fisher, A. Ruhoff, A. J. Purdy, J. Huntington

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Evapotranspiration (ET) accounts for the majority of water available from precipitation in the terrestrial water cycle, and improvements to the accuracy, resolution, and coverage of ET data can enhance hydrologic models and assessments. The OpenET collaboration of six remotely sensed ET modeling teams has demonstrated that an ensemble approach to ET estimation generally provides improved accuracy relative to individual ensemble members. The performance of individual models has been shown to vary by land cover type and climate zone, but a thorough study of the variables that influence model performance differences has not yet been conducted. In this paper, we model …

Surveys And Modeling: Using An Existing Survey To Describe And Compare Populations To Better Inform On Groundwater Model Inputs, M. Austin Wise

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Mississippi River Valley “Alluvial Aquifer” is among the most agriculturally significant aquifers in the United States. However, parts of the aquifer are exceeding sustainable yield as development of the water source continues. Survey research in other aquifers, such as the High Plains (Ogallala) Aquifer, has helped to understand the perceptions and attitudes of irrigators withdrawing from their aquifers. This led to numerous questions: What are the attitudes of irrigators in the Alluvial Aquifer region? How do they compare to irrigators in other regions of the country? Can their intentions be used to generate more accurate inputs when modeling adoption …

Exploring The Application Of Repeated Microgravity Surveys To Monitor Groundwater Level Variations In Nebraska, Kaitlin M. Steinauer

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Groundwater is an important resource in the state of Nebraska for supporting industries and ecosystems. Monitoring this vast resource ensures its continued availability for generations to come. However, monitoring utilizes well data, and if a well is not present in a desired location, geophysical methods can be explored. This project tests the capability of repeated gravity surveys over Nebraska’s aquifers to monitor groundwater levels throughout 2024.

Two study areas were selected in Eastern Nebraska. The first is in Oakland, Nebraska, over a confined aquifer system. The second is in Plymouth, Nebraska, and exhibits unconfined conditions. Four sites were chosen to …

Multiscale Drivers Of Water Level Fluctuations And Nutrient Availability In Small Intermittent Reservoirs In The Us Midwest, Uchechukwu Vitus Chinatu Ogbenna

School of Natural Resources: Dissertations, Theses, and Student Research

Reservoir dynamics are often captured by fluctuations in water surface elevation, which reflect a complex interplay of hydrologic inputs, climatic conditions, land use influences, and management operations. While water level fluctuations (WLFs) in large regulated systems have been widely studied, the drivers and implications of WLFs in small reservoirs, particularly those fed by intermittent streams, remain poorly understood. Here, we examined the temporal dynamics of WLFs and their relationship with nutrient availability in nine small reservoirs in the U.S. Midwest using daily records from 1985 to 2022. We used water level classification from modified Zscore and transition matrices to assess …

Heat Storage Using High Temperature Borehole Heat Exchangers, Jack Horvath

All Theses

The use of renewable energy sources such as wind and solar power is growing, and with it comes an increased need to store excess energy when it is generated and release it on demand. Moderate temperature thermal energy storage in the subsurface is widely used to heat buildings, but high temperatures, greater than 120℃, are required to power generators that convert stored heat to electricity. High temperature heat can be generated from solar collectors or other means and then transferred to the subsurface using borehole heat exchangers (BHE). A BHE consists of a closed-loop pipe system used to circulate a …

Assessing Meteorological Impacts On Hydrological Switches In The Conus, Surendra Maharjan, Wenzhao Li, Sujan Shrestha, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydrological switches, defined as rapid transitions between extreme meteorological events such as droughts and floods, are becoming increasingly frequent across the contiguous United States (CONUS) due to climate variability. This study analyzes the spatial and temporal patterns of these hydrological switches and their correlation with large-scale meteorological indices, such as the Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI). Streamflow data from the US Geological Survey (USGS) is analyzed to investigate the impact of meteorological drivers on hydrological variability. Results indicate that regions dependent on snowmelt exhibit delayed hydrological responses to climatic conditions, while areas in the Eastern …

Quantifying The Impacts Of Land Use And Land Cover Change On Urbanizing Agricultural Systems, Carli Beisel

Boise State University Theses and Dissertations

Western water supplies are increasingly stressed by the compounding impacts of population growth, urbanization, and climate change. Rising temperatures in Idaho are shifting precipitation patterns, with more falling as rain rather than snow. This reduces snowpack and the resulting snowmelt, which serves as the predominant water source for agriculture. At the same time, urbanization of agricultural land decreases surface permeability, replaces irrigated fields, and amplifies the impacts of climate change. The Treasure Valley, located in southwestern Idaho, has been rapidly urbanizing; urban land cover has grown by 52% from 1985 to 2021. Understanding how land use and land cover changes …

Groundwater-Dependent Ecosystems In Southeastern Utah: An Integrated Analysis Of Hydrology, Ecology, And Landscape Change, Colten Lay

All Graduate Reports and Creative Projects, Fall 2023 to Present

In Southeastern Utah, springs play a critical role in sustaining groundwater-dependent ecosystems (GDEs) in a semi-arid environment. However, they remain understudied and face growing threats from climate change, land use modifications, and hydrologic alterations. This study addresses knowledge gaps in spring occurrence, hydrologic function, and ecological condition by integrating field surveys, remote sensing, and geospatial analysis across multiple spatial scales. It provides a comprehensive assessment of spring hydrology, water quality, and ecological conditions using field surveys, remote sensing, and GIS analysis to establish a foundational baseline of GDE resources in the region. I applied a multi-scale monitoring approach across the …

Dream Pilot Project: Analysis Of Groundwater Development At Six Villages In Ethiopia, Lindsay K. Gordon

All Graduate Reports and Creative Projects, Fall 2023 to Present

This study presents a hydrogeologic assessment of the Distributed Renewable Energy Agriculture Modalities (DREAM) pilot project, an ongoing groundwater development initiative in rural Ethiopia. This project integrates solar-powered groundwater infrastructure across six villages to improve water access, agricultural productivity, and economic stability.

Fourteen production wells were installed at Murche, four at Dalle, and additional test wells at Murche, Dalle, Chefe Kora, and Huluku. Transmissivity values and the number of wells at Murche suggest that local water needs are currently being met. In contrast, fewer wells were drilled at Dalle. This reflects the high cost of well construction relative to yield, …

Unraveling Snow And Rain Contributions To Streamflow Through A Methodological Investigation On Cold And Warm Season End-Members, Rachel Grena

Boise State University Theses and Dissertations

Water supply and demand are encountering unique challenges in the western United States as climate change impacts the availability of water resources. Much of the west relies on high mountain snowpack to maintain consistent streamflow throughout the dry, warm season months. Temperatures often rise above freezing in the cold season, diminishing the snowpack size, and altering the timing of snowmelt. As droughts become more frequent, water managers are increasingly concerned about the risk of reduced summer streamflow. To understand changing hydrologic patterns, this study utilizes phase changes in precipitation, specifically the distinction between cold and warm season precipitation, and their …

Decoding Teleconnection Impacts On Hydrological Switches In The Conus Using Wavelet Analysis, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Hesham Morgan, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydrometeorological teleconnections are key drivers of hydrological processes, representing the influence of large-scale atmospheric circulation patterns on regional climates. Understanding these teleconnections provides crucial insights into the mechanisms underlying hydrometeorological phenomena, particularly hydrological switches—rapid transitions between extreme events such as droughts and floods. These switches have become increasingly prevalent across the contiguous United States (CONUS), fueled by climate variability and evolving atmospheric patterns. This study utilizes cross-wavelet transform analysis to examine the spatial and temporal dynamics of hydrological switches and their correlations with major teleconnection indices, including NAO, ONI, WP, PDO, PNA, and QBO. The findings indicate significant coherence between …

Insights From Swot Data On Transboundary Upstream-Downstream Impacts In The Nile Basin, Hesham Morgan, Wenzhao Li, Ali Elgendy, Surendra Maharjan, Rejoice Thomas, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study utilizes high-resolution data from NASA's Surface Water and Ocean Topography (SWOT) mission to investigate water dynamics and upstream-downstream impacts across key reservoirs in the Nile Basin. Focusing on the Grand Ethiopian Renaissance Dam (GERD), Rosaries Dam, Merowe Dam, and the Aswan High Dam, the analysis spans 15 months (August 2023 to October 2024). By systematically selecting 30 points across each reservoir, monthly boxplots of surface water elevation were generated, revealing significant temporal and spatial variability. The results show that GERD’s filling phase led to a steady increase in water levels (peaking at ~615 meters from June to October …

Analysis Of The Impact And Adaptation Of Tidal Floods From Coastal Landscape Area Communities In Poasia District, Kendari City, Indonesia, La Ode Hadini, La Aba, Noor Husna Khairisa, Nikita Jasmine Almira

Jurnal Pendidikan Geografi: Kajian, Teori, dan Praktek dalam Bidang Pendidikan dan Ilmu Geografi

Poasia District is located in the coastal area of the southern part of Kendari City, which is highly susceptible to tidal flooding. However, the extent of the community's exposure to these events and their subsequent adaptation measures remain to be fully delineated. This study examines the impacts of tidal flooding and the adaptation patterns of the Poasia Coastal Community to the tidal flood disaster. This research employed a descriptive qualitative method, which was carried out through document review, interviews involving 34 respondents, and field observations. The results of this study indicate that tidal flooding exerts a negative impact on the …

Limited Soil Water Recharge In Summer Affects Seasonal Isotopic Signatures Of Tree Xylem Water, Marius G. Floriancic, Gregory R. Goldsmith, Harsh Beria, Scott T. Allen, James W. Kirchner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent studies have reported that xylem waters in forest trees during the summer growing season are often isotopically similar to winter, rather than summer, precipitation. Several hypotheses have been proposed to explain this observation, which can be viewed as a form of ecohydrological separation, but empirical tests spanning space and time remain limited. We hypothesise that variations in the seasonal origin of precipitation found in tree xylem waters can be explained by seasonal differences in soil water recharge. We test this hypothesis by evaluating to what extent climatic aridity can explain seasonal signals in extensive surveys of the isotope ratios …

One Year Of Analysis Of Pfas Contamination In Surface Waters Of The West Plains Region Of Spokane County, Jerusha R. Hampson

2025 Symposium

The West Plains has been significantly impacted by PFAS contamination due to the decades-long use of aqueous film-forming foam (AFFF) for firefighting training at both Fairchild Air Force Base (FAFB) and the Spokane International Airport (SIA). Groundwater contamination is significant, but less work had been done to understand contamination in surface waters. We now have over a year of data with most locations were sampled seasonally. Though FAFB and SIA are likely sources for some of the contamination, other, smaller sources exist. Surface waters are important to study as they form the boundaries of the West Plains and often function …

Remote Sensing-Based Assessment Of Evapotranspiration Patterns In A Unesco World Heritage Site Under Increasing Water Competition, Maria C. Moyano, Monica Garcia, Luis Juana, Laura Recuero, Lucia Tornos, Joshua B. Fisher, Néstor Fernández, Alicia Palacias-Orueta

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In water-scarce regions, natural ecosystems and agriculture increasingly compete for limited water resources, intensifying stress during periods of drought. To assess these competing demands, we applied a modified PT-JPL model that incorporates the thermal inertial approach as a substitute for relative humidity (RH) in estimating soil evaporation—a method that significantly outperforms the original PT-JPL formulation in Mediterranean semi-arid irrigated areas. This remote sensing framework enabled us to quantify spatial and temporal variations in water use across both natural and agricultural systems within the UNESCO World Heritage site of Doñana. Our analysis revealed an increasing evapotranspiration (ET) trend in intensified agricultural …

A Novel Approach To Increase Accuracy In Remotely Sensed Evapotranspiration Through Basin Water Balance And Flux Tower Constraints, Kul Khand, Gabriel B. Senay, Mackenzie Friedrichs, Koong Yi, Joshua B. Fisher, Lixin Wang, Kosana Suvočarev, Arman Ahmadi, Housen Chu, Stephen Good, Kanishka Mallick, Justine Missik, Jacob A. Nelson, David E. Reed, Tianxin Wang, Xiangming Xiao

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Remote sensing-derived evapotranspiration (RSET) products capture the spatiotemporal variations of evapotranspiration (ET) from field to basin scales with unprecedented details. However, their accuracy varies across RSET estimation methods and diverse hydroclimate regions. While ET modeling efforts to account for biophysical processes and controlling parameters have made good progress in recent years, a parallel approach of integrating in-situ ET with RSET could reduce biases in RSET products. Basin water balance ET (WBET) and flux tower ET are widely applied to evaluate RSET accuracy, yet such ET measurements are rarely used for RSET bias corrections, especially for large area applications. To address …

Catching A Fever: A Comparison Of Vachellia Xanthophloea Populations In The Limpopo And Luvuvhu River Floodplains Of The Makuleke Contractual Park, Kianie B. David

School of Natural Resources: Dissertations, Theses, and Student Research

This study investigates patterns of stand structure regeneration, growth characteristics, and coarse woody debris (CWD) patterns in Vachellia xanthophloea (fever tree) stands within the Makuleke Contractual Park (MCP), a semi-arid savanna system in northern Kruger National Park (KNP), South Africa. Fieldwork was conducted across two stand types: a monospecific fever tree stand in Rietbok Vlei and a mixed-species stand in the Western Nhlangaluwe Floodplain where fever tree is established with Faidherbia albida (ana tree). Data were collected from 20 total 1/4-acre (1,011 m²) circular plots between both stands in 2024 and 2025, including seedling root collar diameter (RCD), …

Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

What is groundwater? Groundwater is water that fills and moves between spaces in underground rocks, gravel, sand, or other materials.

The Surface Water And Ocean Topography (Swot) Mission For River And Lake Ice Application, Sunwoo Yoon

Earth Sciences Theses and Dissertations

The Surface Water and Ocean Topography (SWOT) mission, launched in December 2022, is designed for global survey of Earth’s surface water. However, the seasonal freezing of lakes and rivers combined with SWOT’s unique interferometric radar characteristics presents a valuable opportunity to assess its potential for river and lake ice applications. In this dissertation, I first compare backscatter characteristics over open water and frozen lakes and rivers. I demonstrate strong contrast in backscatter between water and ice while accounting for incidence angle, highlighting SWOT’s capability to discriminate between surface cover types. However, overlapping backscatter signatures suggest further investigation of drivers of …

Atmospheric Teleconnection Patterns And Hydrological Whiplashes In The Western U.S., Wenzhao Li, Surendra Maharjan, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Western U.S. is undergoing notable transformations in its hydrological patterns, distinguished by rising variability and recurrent “whiplash” shifts between extreme wet and dry phases. Our comprehensive analysis of 469 streamflow stations from 1981 to 2023 reveals a substantial increase in hydrological whiplash events, with a peak of 206 stations experiencing dry-to-wet whiplash in the early 1990s. We establish strong links between these streamflow extremes and sub-seasonal to seasonal teleconnection factors, particularly the Western Pacific Oscillation (WP) and Eastern Pacific/North Pacific Oscillation (EPO). Additionally, we demonstrate the combined impacts of the El Niño-Southern Oscillation (ENSO) and the Madden-Julian Oscillation (MJO), …

Using Radium Isotopes To Compare Nutrient Inputs Via Submarine Groundwater Discharge To Offshore Export On The West Florida Shelf, Andrew L. Lindgren

OES Theses and Dissertations

Radium isotopes have been used to trace submarine groundwater discharge (SGD) and associated nutrient and metal inputs into the coastal ocean. They have also been used to estimate rates of diffusive mixing and export fluxes of dissolved constituents offshore. However, use of both approaches in tandem to determine the fate of groundwater inputs after they enter the coastal ocean is still relatively unexplored. Radium isotopes and nutrients were measured in two cross-shelf cruises on the West Florida Shelf in different seasons and in quarterly sampling of offshore wells. Through 226Ra mass balance and 223Ra-derived diffusive mixing rates, inputs of nutrients …

Investing Hysteresis In Floodplain Dynamics Of Lakes In The Middle St. Johns River Using Sentinel-1 Sar Imagery, Keenan Hubbard

Doctoral Dissertations and Master's Theses

Floodplain dynamics are often complex, with hysteresis potentially affecting the temporal relationship between flood stage and flood extent during subsequent inundation phases. This study leverages Sentinel-1 synthetic aperture radar (SAR) imagery to map flood extent in the Middle St. Johns River Lake floodplains and examine the presence of hysteresis during flood events. SAR scenes corresponding to river gauge readings were analyzed from the rising and falling limbs of a flood hydrograph. By comparing these flood maps, we assess differences in inundated areas at equivalent water levels during each stage of the flood event. The findings aim to enhance flood monitoring …

Evaluation Of Ecostress Collection 2 Evapotranspiration Products: Strengths And Uncertainties For Evapotranspiration Modeling, Zoe Amie Pierrat, Adam J. Purdy, Gregory Halverson, Joshua B. Fisher, Kanishka Mallick, Madeleine Pascolini-Campbell, Youngryel Rye, Martha C. Anderson, Claire Villanueva-Weeks, Margaret C. Johnson, Brenna Hatch, Evan Davis, Yun Yang, Kerry Cawse-Nicholson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) collects thermal observations from the International Space Station to support evapotranspiration (ET) research at fine spatial resolutions (70 m × 70 m). Initial ET from ECOSTRESS Collection 1 was used in scientific research and applications, though subsequent analyses identified areas for improvement. This study outlines updates to ECOSTRESS Collection 2 ET and presents an accuracy assessment of ET and auxiliary variables validated against in situ data from AmeriFlux. Key updates in Collection 2 include use of four independent model estimates of instantaneous latent energy (LE) and improved auxiliary forcing data. …

Enhancing Water Scarcity Resilience In Egypt Through Machine Learning-Driven Phenological Crop Mapping And Water Use Efficiency Analysis, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Aqil Tariq, Rejoice Thomas, Cyril Rakovski, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Agriculture forms the backbone of Egypt’s economy, with the Nile Valley and Delta serving as key production zones for crops like wheat, rice, and clover. However, the sector faces mounting pressure from water scarcity, as it depends almost entirely on the Nile for irrigation, making it necessary to map major crops for assessing Water Use Efficiency (WUE) and informing agricultural planning. In this study, we used machine learning (ML) techniques—specifically Support Vector Machine (SVM) to time-series phenological data and optical indices (Enhanced Vegetation Index (EVI), Bare Soil Index (BSI), Land Surface Water Index (LSWI), Normalized Difference Vegetation Index (NDVI), and …