Earth Sciences Commons^™

Gravity And Passive Seismic Methods Used Jointly For Understanding The Subsurface In A Glaciated Terrain: Dowling And Maple Grove Quadrangles, Barry County, Michigan, Scott A. Feldpausch

Masters Theses

The Horizontal to Vertical Spectral Ratio (HVSR) passive, single sensor seismic technique has been used together with gravimetry to study the topography hidden below the glacial drift of two 7.5’ quadrangles in Barry Co., MI. 265 stations were observed with both instruments along roads at nominal spacings of about 0.4 to 0.8 km. Occasional water wells and oil wells with documented penetrations of the base of glacial were used to calibrate the local power law regression calibration. This was also compared with the statewide calibration curve previously established. Results are presented as maps of Simple Bouguer Anomaly, Residual Bouguer Anomaly, …

Stable Isotope Chemistry In Titan Haze Aerosol, Allison Wold, Thomas Gautier, Jennifer Stern, Joshua Sebree, Melissa Trainer

Research in the Capitol

Titan, a moon of Saturn, has a thick atmosphere made up of nitrogen and a few percent methane, with a surface pressure of 1.5x that of Earth. Titan’s atmosphere is believed to be that similar to that of early Earth before the rise of O2. One significant source of information on the history and evolution of the atmosphere is the measurement of stable isotopes of elements in the molecules of major gases such as nitrogen, methane, and higher order hydrocarbons. The fractionation associated with the formation of Titan aerosol analogs are explored in the laboratory as a function of environmental …

Influence Of Internal Variability On Population Exposure To Hydroclimatic Changes, Justin S. Mankin, Daniel Viviroli, Mesfin Mekonnen, Arjen Y. Hoekstra, Radley M. Horton, Jason E. Smerdon, Noah S. Diffenbaugh

Daugherty Water for Food Global Institute: Faculty Publications

Future freshwater supply, human water demand, and people’s exposure to water stress are subject to multiple sources of uncertainty, including unknown future pathways of fossil fuel and water consumption, and ‘irreducible’ uncertainty arising from internal climate system variability. Such internal variability can conceal forced hydroclimatic changes on multi-decadal timescales and near-continental spatial-scales. Using three projections of population growth, a large ensemble from a single Earth system model, and assuming stationary per capita water consumption, we quantify the likelihoods of future population exposure to increased hydroclimatic deficits, which we define as the average duration and magnitude by which evapotranspiration exceeds precipitation …

Uwrl Students Sweep Awwa 2017 Scholarships, Utah Water Research Laboratory

News

USU Civil Engineering and UWRL Students win scholarships from American Water Works Association. The scholarships support students studying water quality, supply, and treatment in the West. The scholarship is awarded to both graduate and undergraduate students, with USU taking them all this year.

Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger

USF Tampa Graduate Theses and Dissertations

The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study uses …

Modeling The Movement Of Septic Water Chloride Through A Soil Profile, Shawkat Kochary, Tom Byl, Bahzad Noori

Civil and Architectural Engineering Faculty Research

The purpose of this study was to investigate the movement of chloride through a vadose zone located under failed and non-regulated septic tanks of Duhok city, Kurdistan of Iraq, potentially contaminating its groundwater. A physical vadose model (PVM) of a vertical flow direction was built in the laboratory to represent the city soil profile. The size of the PVM was 210 × 122 × 9.7 cm (height, width, and depth). Preliminary soil tests were conducted to better represent the lithology of study area. The PVM was then packed with regional silt clay soil, after modifying its texture, using an innovative …

Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan

Earth, Environment & Sustainability: Faculty Publications

Studies of dissolved organic matter (DOM) transport through terrestrial aquatic systems usually start at the stream. However, the interception of rainwater by vegetation marks the beginning of the terrestrial hydrological cycle making trees the headwaters of aquatic carbon cycling. Rainwater interacts with trees picking up tree-DOM, which is then exported from the tree in stemflow and throughfall. Stemflow denotes water flowing down the tree trunk, while throughfall is the water that drips through the leaves of the canopy. We report the concentrations, optical properties (light absorbance) and molecular signatures (ultrahigh resolution mass spectrometry) of tree-DOM in throughfall and stemflow from …

Student, Mahyar Aboutalebi, Wins J. Paul Riley Awra Paper Competition, Utah Water Research Laboratory

News

Mahyar Aboutalebi was selected as a winner and scholarship recipient in the J. Paul Riley AWRA Utah Section Student Paper Competition. The paper, Satellite-based Prediction of Internal Migratory Movement under the Lack of Sufficient water for the Entire U.S.” will go on to compete in the oral presentation contest during the 2017 Spring Runoff Conference.

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder

USF Tampa Graduate Theses and Dissertations

In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …

3d Cave And Ice Block Morphology From Integrated Geophysical Methods: A Case Study At Scărişoara Ice Cave, Romania, Jackson Durain Hubbard

USF Tampa Graduate Theses and Dissertations

Scărişoara Ice Cave has been a catalyst of scientific intrigue and effort for over 150 years. These efforts have revealed and described countless natural phenomena – and in the process have made it one of the most studied caves in the world.

Of especial interest is the massive ice block located within its Great Hall and scientific reservations. The ice block, which is the oldest and largest known to exist in a cave, has been the focus of multiple surveying and mapping efforts, typically ones utilizing traditional equipment. In this study, the goals were to reconstruct the ice block/cave floor …

Regional Greenland Accumulation Variability From Operation Icebridge Airborne Accumulation Radar, Gabriel Lewis, Erich Osterberg, Robert Hawley, Brian Whitmore, Hans Peter Marshall, Jason Box

CGISS Publications and Presentations

The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. An improved understanding of temporal and spatial variability of snow accumulation will reduce uncertainties in GrIS mass balance models and improve projections of Greenland's contribution to sea-level rise, currently estimated at 0.089 ± 0.03 m by 2100. Here we analyze 25 NASA Operation IceBridge accumulation radar flights totaling > 17 700 km from 2013 to 2014 to determine snow accumulation in the GrIS dry snow and percolation zones over the past …

Regional Greenland Accumulation Variability From Operation Icebridge Airborne Accumulation Rradar, Gabriel Lewis, Erich Osterberg, Robert Hawley, Brian Whitmore

Dartmouth Scholarship

The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. An improved understanding of temporal and spatial variability of snow accumulation will reduce uncertainties in GrIS mass balance models and improve projections of Greenland's contribution to sea-level rise, currently estimated at 0.089 ± 0.03 m by 2100. Here we analyze 25 NASA Operation IceBridge accumulation radar flights totaling  >  17 700 km from 2013 to 2014 to determine snow accumulation in the GrIS dry snow and percolation zones over the past …

Characterizing The Evolution Of Slab Inputs In The Earliest Stages Of Subduction: Preliminary Evidence From The Fluid-Mobile Element (B, Cs, As, Li) Systematics Of Izu-Bonin Boninitic Glasses Recovered During Iodp Expedition 352, Keir Aavon Sanatan

USF Tampa Graduate Theses and Dissertations

Fluid-mobile elements (FMEs) such as B, Cs, As, Li and Tl can mobilize readily under low P-T conditions (0.2-0.5 GPa). This makes them effective geochemical tracers that can be used as a way of tracking fluid-rock exchanges at the shallow depths encountered in the earliest stages of subduction.

The Izu-Bonin-Mariana (IBM) subduction system is unique in that it preserves a record of the sequences produced from the onset of subduction through the development of arc magmatism. International Ocean Discovery Program (IODP) Expedition 352 recovered >800m of boninite core material from the earliest IBM magmatic events.

Select boninitic glasses from these …

Spatio-Temporal Dynamics Of Soil Composition And Accumulation Rates In Mangrove Wetlands, Joshua L. Breithaupt

USF Tampa Graduate Theses and Dissertations

Coastal wetlands are globally important environments for biogeochemical cycling and are the object of intensive research related to the sequestration and exchange of carbon with oceans, continents, and the atmosphere. Wetland soil core records of organic carbon (OC) provide insights about future ecosystem responses to global change by identifying temporal variability in the context of environmental changes including sea level rise (SLR), anthropogenic reductions in freshwater flow, and landscape-scale disturbance events. My studies of Gulf of Mexico mangroves involved the use of radiometrically-dated soil cores to identify spatial and temporal accumulation trends of various constituents including organic and carbonate carbon, …

Exploration Of The Northern Illinois Bedrock Surface, Matthew Rhoads

Theses and Dissertations

The purpose of this study is to deconstruct the relationship between the Leaf River anticline and the preglacial bedrock paleo topography at the eastern terminus of the Plum River Fault Zone in Ogle County, Illinois. A geostatistical approach was used to model the subsurface elevation of the bedrock paleo topography and the Leaf River anticline. The contour maps derived from the elevation models provided detailed depictions of the ancient bedrock landscape and subsurface structure in the study area. The Leaf River anticline is interpreted to be a component of hanging wall anticline at the terminus of the Plum River Fault …

Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver

United States Environmental Protection Agency: Publications

As saltmarsh habitat continues to disappear, understanding the factors that influence the population dynamics of saltmarsh breeding birds is an important step in the conservation of these declining species. Using 5 yrs (2011–2015) of demographic data, we evaluated and compared apparent adult survival and nest survival of Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrows at the Edwin B. Forsythe National Wildlife Refuge in New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marshes) on adult and nest survival to aid in prioritizing future management or restoration actions. Apparent adult …

A Numerical Model Investigation Of The Role Of The Glacier Bed In Regulating Grounding Line Retreat Of Thwaites Glacier, West Antarctica, Michael Scott Waibel

Dissertations and Theses

I examine how two different realizations of bed morphology affect Thwaites Glacier response to ocean warming through the initiation of marine ice sheet instability and associated grounding line retreat. A state of the art numerical ice sheet model is used for this purpose. The bed configurations used are the 1-km resolution interpolated BEDMAP2 bed and a higher-resolution conditional simulation produced by John Goff at the University of Texas using the same underlying data. The model is forced using a slow ramp approach, where melt of ice on the floating side of the grounding line is increased over time, which gently …

Impact Of Icebergs On Net Primary Productivity In The Southern Ocean, Shuang-Ye Wu, Shugui Hou

Department of Earth, Environment and Sustainability Faculty Publications

Productivity in the Southern Ocean (SO) is iron-limited, and supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine environment. However, recent studies show that icebergs could provide a comparable amount of bioavailable iron to the SO as aeolian dust. In addition, small-scale areal studies suggest increased concentrations of chlorophyll, krill, and seabirds surrounding icebergs. Based on previous research, this study aims to examine whether iceberg occurrence has a significant impact on marine productivity at the scale of the SO, using remote sensing data of iceberg occurrences and ocean net primary productivity …

Timing Of Mid-Crustal Ductile Extension In The Northern Snake Range Metamorphic Core Complex, Nevada: Evidence From U/Pb Zircon Ages, Jeffrey Lee, Terrence Blackburn, Scott Johnston

All Faculty Scholarship for the College of the Sciences

Metamorphic core complexes within the western U.S. record a history of Cenozoic ductile and brittle extensional deformation, metamorphism, magmatism, and exhumation within the footwalls of high-angle Basin and Range normal faults. In models proposed for the formation of metamorphic core complexes there is a close temporal and spatial link between upper crustal normal faulting, lower crustal ductile extension and flow, and detachment faulting. To provide constraints on the timing of ductile extension in the northern Snake Range metamorphic core complex (Nevada) and thereby test these models, we present new 238U-206Pb dates on zircons from both deformed and undeformed rhyolite dikes …

Analyzing Glacier Surface Motion Using Lidar Data, Jennifer W. Tellig, Craig Glennie, Andrew G. Fountain, David C. Finnegan

Geology Faculty Publications and Presentations

Understanding glacier motion is key to understanding how glaciers are growing, shrinking, and responding to changing environmental conditions. In situ observations are often difficult to collect and offer an analysis of glacier surface motion only at a few discrete points. Using light detection and ranging (LiDAR) data collected from surveys over six glaciers in Greenland and Antarctica, particle image velocimetry (PIV) was applied to temporally-spaced point clouds to detect and measure surface motion. The type and distribution of surface features, surface roughness, and spatial and temporal resolution of the data were all found to be important factors, which limited the …

Evidence Of Erosional Self-Channelization Of Pyroclastic Density Currents Revealed By Ground-Penetrating Radar Imaging At Mount St. Helens, Washington (Usa), Andrew C. Gase, Brittany D. Brand, John H. Bradford

Geosciences Faculty Publications and Presentations

The causes and effects of erosion are among the least understood aspects of pyroclastic density current (PDC) dynamics. Evidence is especially limited for erosional self-channelization, a process whereby PDCs erode a channel that confines the body of the eroding flow or subsequent flows. We use ground-penetrating radar imaging to trace a large PDC scour and fill from outcrop to its point of inception and discover a second, larger PDC scour and fill. The scours are among the largest PDC erosional features on record, at >200 m wide and at least 500 m long; estimated eroded volumes are on the order …

Responses Of Terrestrial Ecosystem Phosphorus Cycling To Nitrogen Addition: A Meta-Analysis, Qi Deng, Dafeng Hui, Samuel Dennis, Chandra Reddy

Agricultural and Environmental Sciences Faculty Research

Aim

Anthropogenic additions of nitrogen (N) are expected to drive terrestrial ecosystems toward greater phosphorus (P) limitation. However, a comprehensive understanding of how an ecosystem's P cycle responds to external N inputs remains elusive, making model predictions of the anthropogenic P limitation and its impacts largely uncertain.

Location

Global.

Time period

1986-2015.

Major taxa studied

Terrestrial ecosystems.

Methods

We conducted a meta-analysis including 288 independent study sites from 192 articles to evaluate global patterns and controls of 10 variables associated with ecosystem P cycling under N addition.

Results

Overall, N addition increased biomass in plants (+34%) and litter (+15%) as …

On The Relationship Between Spring Nao And Snowmelt In The Upper Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study examines the relationship between the North Atlantic Oscillation (NAO) and snowmelt in spring in the upper southwestern states of the United States (UP_SW) including California, Nevada, Utah, and Colorado, using SNOTEL datasets for 34 yr (1980–2014). Statistically significant negative correlations are found between NAO averages in the snowmelt period and timings of snowmelt (i.e., positive NAO phases in spring enhance snowmelt, and vice versa). It is also found that correlations between El Niño–Southern Oscillation and snowmelt are negligible in the region. The NAO–snowmelt relationship is most pronounced below the 2800-m level; above this level, the relationship becomes weaker. …

Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo

Theses and Dissertations

Nutrients such as nitrate and phosphorus are necessary for life, but excessive amounts can be detrimental. Large amounts of nutrients entering bodies of water can lead to hypoxic zones such as the one in the Gulf of Mexico. Nutrients are also problematic in drinking water reservoirs, as high concentrations of nitrate in drinking water can cause health conditions such as blue baby syndrome and high phosphorus concentrations can lead to algal blooms. Suspended sediment leads to reservoir sedimentation, habitat degradation, and is able to transport particulate nutrients. High nutrient and sediment concentrations are a recurring problem in the drinking water …

A Multi-Proxy Stalagmite Reconstruction Of The Climate Of Southwestern North America From The Middle To Late Holocene, Christine Allen

Earth and Planetary Sciences ETDs

The seasonal balance of moisture has a significant effect on natural ecosystems and culture in southwestern North America (SWNA), and it thus is necessary to understand the cause of this moisture variability in order to better predict the scope of potential future changes. Studies of modern SWNA climate indicate that most of the annual moisture at this site comes from monsoonal summer precipitation and a lesser amount of Pacific winter moisture. The climate of the Holocene is of particular interest for constraining natural variability of interglacial climates prior to any anthropogenic influence. An overall transition to a wetter Late Holocene …

The Future Of Evapotranspiration: Global Requirements For Ecosystem Functioning, Carbon And Climate Feedbacks, Agricultural Management, And Water Resources, Joshua B. Fisher, Forrest S. Melton, Elizabeth M. Middleton, Christopher Hain, Martha C. Anderson, Richard G. Allen, Matthew Mccabe, Simon Hook, Dennis Baldocchi, Philip A. Townsend, Ayse Kilic, Kevin Tu, Diego Miralles, Johan Perret, Jean-Pierre Lagouarde, Duane Waliser, Adam J. Purdy, Andrew French, David Schimel, James S. Famiglietti, Graeme Stephens, Eric F. Wood

Department of Earth and Atmospheric Sciences: Faculty Publications

The fate of the terrestrial biosphere is highly uncertain given recent and projected changes in climate. This is especially acute for impacts associated with changes in drought frequency and intensity on the distribution and timing of water availability. The development of effective adaptation strategies for these emerging threats to food and water security are compromised by limitations in our understanding of how natural and managed ecosystems are responding to changing hydrological and climatological regimes. This information gap is exacerbated by insufficient monitoring capabilities from local to global scales. Here, we describe how evapotranspiration (ET) represents the key variable in linking …

Carbon Sequestration By Australian Tidal Marshes, Peter I. Macreadie, Q. R. Oliver, J. J. Kelleway, Oscar Serrano, P. E. Carnell, C. J. Ewers Lewis, T. B. Atwood, J. Sanderman, J. Baldock, R. M. Connolly, C. M. Duarte, Paul Lavery, A. Steven, C. E, Lovelock

Research outputs 2014 to 2021

Australia’s tidal marshes have suffered significant losses but their recently recognised importance in CO2 sequestration is creating opportunities for their protection and restoration. We compiled all available data on soil organic carbon (OC) storage in Australia’s tidal marshes (323 cores). OC stocks in the surface 1 m averaged 165.41 (SE 6.96) Mg OC ha − 1 (range 14 – 963 Mg OC ha − 1). The mean OC accumulation rate was 0.55 ± 0.02 Mg OC ha − 1 yr − 1. Geomorphology was the most important predictor of OC stocks, with fluvial sites having twice the stock of OC …

Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

The High Plains Aquifer underlies much of Nebraska (Figure 1). It is the primary source of groundwater within the Upper Loup Natural Resources District (ULNRD) of central Nebraska (Figure 2). Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. A general lack of water level observations in the region (Figure 3), recently developed groundwater irrigated acres along the upper Calamus River (Figure 4), falling spring water levels measured in existing irrigation wells (Figure 5), and a stable to falling stream …

Quantifying The Short-Term Dynamics Of Soil Organic Carbon Decomposition Using A Power Function Model, Weiping Zhou, Jinhong He, Dafeng Hui, Weijun Shen

Biology Faculty Research

Introduction

Soil heterotrophic respiration (R _h, an indicator of soil organic carbon decomposition) is an important carbon efflux of terrestrial ecosystems. However, the dynamics of soil R _h and its empirical relations with climatic factors have not been well understood.

Methods

We incubated soils of three subtropical forests at five temperatures (10, 17, 24, 31, and 38 °C) and five moistures (20, 40, 60, 80, and 100% water holding capacity (WHC)) over 90 days. R _h was measured throughout the course of the incubation. Three types of models (log-linear, exponential, and power model) were fitted to the measurements …

Assessment Of Nasa Airborne Laser Altimetry Data Using Ground-Based Gps Data Near Summit Station, Greenland, Kelly M. Brunt, Robert L. Hawley, Eric R. Lutz, Michael Studinger

Dartmouth Scholarship

A series of NASA airborne lidars have been used in support of satellite laser altimetry missions. These airborne laser altimeters have been deployed for satellite instrument development, for spaceborne data validation, and to bridge the data gap between satellite missions. We used data from ground-based Global Positioning System (GPS) surveys of an 11 km long track near Summit Station, Greenland, to assess the surface–elevation bias and measurement precision of three airborne laser altimeters including the Airborne Topographic Mapper (ATM), the Land, Vegetation, and Ice Sensor (LVIS), and the Multiple Altimeter Beam Experimental Lidar (MABEL). Ground-based GPS data from the monthly …