Oceanography and Atmospheric Sciences and Meteorology Commons^™

Bonnet Carré Spillway Freshwater Transport And Corresponding Biochemical Properties In The Mississippi Bight, Sabrina M. Parra, Virginie Sanial, Adam D. Boyette, M. Kemal Cambazoglu, Inia M. Soto, Adam T. Greer, Luciano M. Chiaverano, Angie Hoover, Michael S. Dinniman

CCPO Publications

Large freshwater pulses to coastal ecosystems change local hydrologic regimes and alter biogeochemical processes. The Mississippi Bight coastal ecosystem, located in the northern Gulf of Mexico shelf, is influenced by extensive freshwater inputs: the Mississippi River (MSR) and several smaller rivers to the east. Under river flood conditions, MSR waters flow through the Bonnet Carré Spillway (BCS) to relieve pressure on levees in New Orleans, Louisiana. In 2015, mild wintertime temperatures and heavy rainfall throughout the MSR watershed led to extreme flooding and prompted an unusually early BCS opening on January 10, 2016 for 23 days. This study examines the ...

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning ...

What Is The U.S. Drought Monitor?, National Drought Mitigation Center

Publications of the National Drought Mitigation Center

The USDA uses the map as a trigger for programs that help agricultural producers recover from drought and other natural disasters:

Livestock Forage Disaster Program (LFP)

Emergency Assistance for Livestock, Honeybees, and Farm Raised Fish Program (ELAP)

Fast-Track Secretarial Disaster Declarations

Emergency Loans Program

The U.S. Drought Monitor Network: Improving Drought Early Warning, The U.S. Drought Monitor Network

Publications of the National Drought Mitigation Center

WHAT IS THE U.S. DROUGHT MONITOR NETWORK?

WHO ARE THE OBSERVERS?

WHAT BENEFITS?

The network in action

HOW DOES IT WORK?

WHO CREATES THE MAP?

What Is The Limiting Nutrient In Winter In Urban Reservoirs? A Case Study., Precious Nyabami

Dissertations & Theses in Earth and Atmospheric Sciences

The importance of reservoirs in widely acknowledged by urban population, yet little is understood scientifically about their ability to process nutrients deposited into them in winter. Nutrients in waste water, lawns and construction runoff are deposited into reservoirs and several ecosystem services are lost which leads to what several researchers call “the urban syndrome”. Some studies have been done on the winter limnology of lakes, yet little is understood about the same process in reservoirs. To fill this missing knowledge gap, a study on one of Nebraska’s lakes (Holmes’ lake) was done. In this study, we simulated how phosphorus ...

Massive Peatland Carbon Banks Vulnerable To Rising Temperatures, A. M. Hopple, R. M. Wilson, M. Kolton, Cassandra A. Zalman, J. P. Chanton, J. Kostka, P. J. Hanson, Jason K. Keller, S. D. Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatlands contain one-third of the world’s soil carbon (C). If destabilized, decomposition of this vast C bank could accelerate climate warming; however, the likelihood of this outcome remains unknown. Here, we examine peatland C stability through five years of whole-ecosystem warming and two years of elevated atmospheric carbon dioxide concentrations (eCO₂). Warming exponentially increased methane (CH₄) emissions and enhanced CH₄ production rates throughout the entire soil profile; although surface CH₄ production rates remain much greater than those at depth. Additionally, older deeper C sources played a larger role in decomposition following prolonged warming. Most troubling ...

Iron-Mediated Organic Matter Decomposition In Humid Soils Can Counteract Protection, Chunmei Chen, Steven J. Hall, Elizabeth Coward, Aaron Thompson

Ecology, Evolution and Organismal Biology Publications

Soil organic matter (SOM) is correlated with reactive iron (Fe) in humid soils, but Fe also promotes SOM decomposition when oxygen (O2) becomes limited. Here we quantify Fe-mediated OM protection vs. decomposition by adding 13C dissolved organic matter (DOM) and 57FeII to soil slurries incubated under static or fluctuating O2. We find Fe uniformly protects OM only under static oxic conditions, and only when Fe and DOM are added together: de novo reactive FeIII phases suppress DOM and SOM mineralization by 35 and 47%, respectively. Conversely, adding 57FeII alone increases SOM mineralization by 8% following oxidation to 57FeIII. Under O2 ...

Building Adaptive Capacity In Tribal Communities Of The Missouri River Basin To Manage Drought And Climate Extremes: A Case Study From The Wind River Indian Reservation, Crystal J. Stiles, Natalie Umphlett, Mitch Cottenoir

HPRCC Personnel Publications

Native American peoples of the Northern and Central Plains have long endured harsh climate conditions, such as floods and droughts, and they possess valuable traditional knowledges that have enhanced their resilience to these extreme events. However, in recent times, limited capacity to adapt to a rapidly changing climate combined with a lack of resources have increased tribes’ vulnerability to climate extremes and their associated impacts. In response, a number of projects have been developed to assist tribes with their self-identified climate- and drought-related needs, particularly in the context of on-reservation decision-making. In this case study, we present an engagement strategy ...

Examining Terrain Effects On Upstate New York Tornado Events Utilizing High-Resolution Model Simulations, Luke Lebel

Atmospheric & Environmental Sciences

The region at the intersection of the Mohawk and Hudson valleys of New York is characterized by complex terrain. It has been hypothesized that this complex terrain may have an impact on the development and evolution of severe convection in the region. Specifically, previous research has hypothesized that terrain-channeled flow in the Hudson and Mohawk valleys contributed to increased low-level wind shear and instability in the valleys during past severe weather outbreaks. However, a lack of observations in the region prevented this hypothesis from being robustly tested.

The goal of this study is to further examine this hypothesis and complement ...

High-Resolution Simulation Of A Tornado In Bangladesh On 13 May 1996, Katherine Hollinger

Atmospheric & Environmental Sciences

The country of Bangladesh has been known to experience some of the deadliest tornado outbreaks in the world. The severe weather season in this region only spans from late March to early May, but can produce significant severe weather outbreaks in that short time. Even with these outbreaks occurring, there has not been extensive analysis completed to evaluate the environmental parameters on these tornado event days in this region.

The goal of this project is to use a Weather Research and Forecasting (WRF) model simulation to evaluate a significant tornado that occurred in the Tangail and Jamalpur districts in Bangladesh ...

Ragweed And Sagebrush Pollen Can Distinguish Between Vegetation Types At Broad Spatial Scales, Hannah M. Carroll, Alan D. Wanamaker, Lynn G. Clark, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Patterns of vegetation distribution at regional to subcontinental scales can inform understanding of climate. Delineating ecoregion boundaries over geologic time is complicated by the difficulty of distinguishing between prairie types at broad spatial scales using the pollen record. Pollen ratios are sometimes employed to distinguish between vegetation types, although their applicability is often limited to a geographic range. The Neotoma Paleoecology Database offers an unparalleled opportunity to synthesize a large number of pollen datasets. Ambrosia (ragweed) is a genus of mesic‐adapted species sensitive to summer moisture. Artemisia (sagebrush, wormwood, mugwort) is a genus of dry‐mesic‐adapted species resilient ...

The Rapid Weakening Of Hurricane Fred (2009), Christina Talamo

Atmospheric & Environmental Sciences

This research project discusses the rapid weakening of Hurricane Fred, a major Category 3 hurricane that occurred in the Atlantic basin during the 2009 Atlantic hurricane season. Between the days of 9 September and 13 September, Fred remained stationary off the coast of Africa in the Atlantic Ocean and never made landfall, all the while consistently weakening over open ocean from a major Category 3 hurricane to a tropical storm. In the Atlantic basin, I will define the rapid weakening, or RW, of a tropical cyclone as a decrease in the storm’s maximum sustained winds by 10.3 m ...

Vims 2019 York River Estuary Data In Support Of: Improved Penetrometer Performance In Stratified Sediment For Cost-Effective Characterization, Monitoring And Management Of Submerged Munitions Sites (Serdp Project: Mr18-1233), Grace M. Massey, Cristin L. Wright, Carl T. Friedrichs

Data

This work complements the efforts by the Virginia Tech Department of Civil & Environmental Engineering in SERDP MR18-1233, as described in the project’s final report (Stark et al, 2020) and in the Master’s thesis by Dennis Kiptoo (Kiptoo, 2020). One of the objectives of the project was to improve calibration of the Bluedrop free fall penetrometer (FFP) with high resolution sampling of a variety of sediment types. To accomplish this, a series of 9 stations over 12 cruises were visited along the York River, an estuary in the Virginia portion of the Chesapeake Bay, and in the Pamunkey River ...

Vims 2019 Potomac River Estuary Data In Support Of: Improved Penetrometer Performance In Stratified Sediment For Cost-Effective Characterization, Monitoring And Management Of Submerged Munitions Sites (Serdp Project: Mr18-1233), Grace M. Massey, Cristin L. Wright, Carl T. Friedrichs

Data

This work complements the efforts by the Virginia Tech Department of Civil & Environmental Engineering in SERDP MR18-1233, as described in the project’s final report (Stark et al, 2020) and in the Master’s thesis by Dennis Kiptoo (Kiptoo, 2020). Previous work on this project, conducted in the York River during 2018-2918 worked to improve calibration of the Bluedrop free fall penetrometer (FFP) with high resolution sampling of a variety of sediment types (Massey et al, 2020a). Calibration methods developed (Kiptoo, 2020) were used to rapidly identify different sediment types from a grid of 59 Bluedrop PPF stations sampled on ...

The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty

Theses and Dissertations

Eutrophication of surface waters not only impacts the environment but also water treatment processes, the most significant of which is from the effects of algae. During peak algal growth in many southern U.S. reservoirs, inflows that bring nutrients are at an annual minimum, and phosphorus released from bed-sediments is trapped in the hypolimnion. Littoral areas, described as the most productive zone of the lake, may be a possible source of phosphorus that fuels algal growth in the reservoir. I studied an isolated shallow cove in the War Eagle Creek arm of Beaver Lake in Northwest Arkansas to measure, quantify ...

Fish Assemblages Associated With A Newly Deployed Eco-Engineered Artificial Seawall In The Intercoastal Waters Of Port Everglades, Olmo Cinti

HCNSO Student Theses and Dissertations

As the demand for urbanization of coastal areas increases, there is a strong interest to create new infrastructures that would replace natural habitats (Airoldi & Beck, 2007; Dugan et al., 2011). These infrastructures, due to their differences in composition and structure, are often associated with decreasing biodiversity, and proliferation of invasive species (Firth et al., 2014; Moschella et al., 2005). To minimize or attenuate these negative effects of hardening shorelines eco-engineering can be implemented. This kind of approach focuses on the modification of artificial habitats to enhance services that would not be otherwise obtained (Barbier et al., 2011; Mayer-Pinto et al., 2017; Strain ...

Arcgis Analysis Of Riparian Zone Restoration Potential In The Middle Creek – Penns Creek Huc-12 Watershed, Julie Benco

Senior Scholars Day

The Middle Creek – Penns Creek HUC-12 watershed contains 48.9 miles of impaired streams out of the greater 73.1 miles of waterways within its capacity. The known impaired streams fail, by the water quality standards set by the Department of Environmental Protection, to meet the qualifications necessary to obtain their regulated attainments. In order to restore the waterways, best management practices (BMPs) can be installed to reduce nutrients, such as nitrogen and phosphorous, and sediment loads. ArcGIS and Model my Watershed are utilized to produce a spatial analysis of the watershed and model how the best management practices will ...

Competitive Interactions Between Creek Chub (Semotilus Atromaculatus) And Brook Trout (Salvelinus Fontinalis) Under The Influence Of Rising Temperatures, Bryan Colby, Jonathan Niles Dr, Matt Wilson, Matthew Persons Dr.

Senior Scholars Day

The natural distribution of many freshwater fish species are limited by their thermal tolerances, both because a species cannot inhabit an area outside its tolerance range and because of increased stress when in environments approaching the limits of its tolerance range. Many species may mediate temperature change physiologically, behaviorally, or both but these changes often may change or compromise interspecific dynamics through the effects on feeding behavior, growth rate, immune responses, and social behavior. In the Appalachian Mountains, creek chub (Semotilus atromaculatus) are found in warm-water and cold-water streams, the latter of which are also inhabited by brook trout (Salvelinus ...

Sea Level Rise Vulnerability Analysis Of Mangrove Ecosystems Using Gis, Kayla Caldwell

HCNSO Student Theses and Dissertations

Climate change is accelerating beyond what is natural due to excessive emissions from human activities. The sea level has been rising for many years and is currently at a rate of 3.6 mm/yr. Mangroves are known to only keep pace with a sea level rate of less than 1.2 mm/yr. Mangroves are particularly vulnerable to rising sea levels if they are not able to keep pace through vertical sediment accretion or inland migration. To test the vulnerability of the south Florida mangrove ecosystems to sea level rise, this study analyzed changes in the mangrove forest coverage ...

Comparative Study Of The Effects Of Light On Photophore Ultrastructure From Two Families Of Deep-Sea Decapod Crustaceans: Oplophoridae And Sergestidae, Jamie E. Sickles

HCNSO Student Theses and Dissertations

Counterillumination, the mechanism by which pelagic species produce bioluminescence to replace the light blocked by their bodies to hide their silhouettes, has been known for over 100 years. However, little is known about how these animals are able to so precisely replicate the intensity of downwelling light. The recent discovery of opsins in photophores (Bracken-Grissom et al. 2020) suggests that these autogenic organs (i.e. non-bacterial) may be sensitive to light, in addition to their function of emitting visible light. The study presented here is 1) the first ultrastructural assessment of photophores in species Systellaspis debilis, Janicella spinicauda, Parasergestes armatus ...

Case Studies Of Colorado Lows And The Impacts On Winter Weather Maintenance, Nathan Rick

Dissertations & Theses in Earth and Atmospheric Sciences

Winter storms of varying degrees plague the Plains each year, bringing with them ice, snow, wind, and cold temperatures which adversely affect public, commercial, and private transportation alike. The Nebraska Department of Transportation (NDOT) adopted a Maintenance Decision Support System (NDOT-MDSS) to aid in their winter weather maintenance practices. NDOT-MDSS ingests data from a variety of numerical weather models as well as real time surface and pavement observations to output both a weather forecast and winter road maintenance recommendation that can be taken into account by NDOT to finalize their maintenance decisions for a specific storm system or road segment ...

Spatial And Temporal Distribution Of Essential And Non-Essential Elements Recorded In Western Arctic Bowhead Whales (Balaena Mysticetus), Samantha L. Shore

HCNSO Student Theses and Dissertations

Western Arctic bowhead whales, Balaena mysticetus, migrate annually among the Bering, Chukchi, and Beaufort seas. Foraging along their route, they use keratinous baleen to filter microscopic zooplankton from the water column. A single baleen plate from an adult bowhead whale grows continuously and stores 20+ years of dietary and environmental data. This study utilized induced coupled plasma-mass spectrometry (ICP-MS) to evaluate concentrations of 14 essential and non-essential elements in baleen samples from nine subsistence-harvested whales, yielding continuous data from 1958–1999 (n=148). Stable isotope data previously reported on these samples provided information on location (Beaufort Sea; Bering/Chukchi seas ...

Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy

Senior Honors Theses

Aquatic organisms often mistake microplastic particulates (MP) as food and inadvertently ingest the particulates, which can biomagnify through the food chain. While MP ingestion is well-researched in the marine environment, little is known about microplastics in freshwater  ecosystems. This project explores MP occurrence in an ecologically significant freshwater invertebrate: crayfish. Crayfish from two Central Virginia streams are collected to identify MP in the digestive tracts and gill filaments, and characterize the MP using analytical chemistry techniques. It was determined that MP were present in the digestive tracts and gill filaments of crayfish collected from both streams, and that MP frequency ...

Reconstructing Deep-Ocean Circulation During Cenozoic Climate Transitions From The Marine Sediment Record, Brian Romans

Sustainability Seminar Series

Ocean circulation plays a critical role in the Earth’s climate system through the storage and transfer of heat and carbon dioxide. The North Atlantic and Southern Ocean are of particular interest because these are regions where deep-water components of global circulation develop. Dr. Romans uses the deep-sea sedimentary record to reconstruct past ocean circulation and its relationship to past climatic and tectonic conditions. He integrates information from a broad range of spatial and temporal scales, from seismic-reflection data that reveals regional sedimentation patterns to high resolution records based on quantitative grain-size analysis from cores. Dr. Romans will present research ...

Sediment Controls Dynamic Behavior Of A Cordilleran Ice Stream At The Last Glacial Maximum, Ellen A. Cowan, Sarah D. Zellers, Juliane Müller, Maureen H. Walczak, Lindsay L. Worthington, Beth E. Caissie, Wesley A. Clary, John M. Jaeger, Sean P. S. Gulick, Jacob W. Pratt, Alan C. Mix, Stewart J. Fallon

Geological and Atmospheric Sciences Publications

The uncertain response of marine terminating outlet glaciers to climate change at time scales beyond short-term observation limits models of future sea level rise. At temperate tidewater margins, abundant subglacial meltwater forms morainal banks (marine shoals) or ice-contact deltas that reduce water depth, stabilizing grounding lines and slowing or reversing glacial retreat. Here we present a radiocarbon-dated record from Integrated Ocean Drilling Program (IODP) Site U1421 that tracks the terminus of the largest Alaskan Cordilleran Ice Sheet outlet glacier during Last Glacial Maximum climate transitions. Sedimentation rates, ice-rafted debris, and microfossil and biogeochemical proxies, show repeated abrupt collapses and slow ...

Learning Set Representations For Lwir In-Scene Atmospheric Compensation, Nicholas M. Westing, Kevin C. Gross, Brett J. Borghetti, Jacob A. Martin, Joseph Meola

Faculty Publications

Atmospheric compensation of long-wave infrared (LWIR) hyperspectral imagery is investigated in this article using set representations learned by a neural network. This approach relies on synthetic at-sensor radiance data derived from collected radiosondes and a diverse database of measured emissivity spectra sampled at a range of surface temperatures. The network loss function relies on LWIR radiative transfer equations to update model parameters. Atmospheric predictions are made on a set of diverse pixels extracted from the scene, without knowledge of blackbody pixels or pixel temperatures. The network architecture utilizes permutation-invariant layers to predict a set representation, similar to the work performed ...

Cave Airflow Mechanism Of A Crevice-Type Cave: A Case Study From Czechia, Martin Kašing, Jan Lenart

International Journal of Speleology

At present, crevice-type caves are investigated mainly by means of geomorphic and geophysical methods. Microclimatic research of this type of caves is underrepresented and is often limited to temperature and humidity measurement only. Yet, microclimatic research of such caves can significantly help in the management and conservation of caves, speleological exploration or analysis of speleothems. Being the first ever research of ventilation within a crevice-type cave, a complex analysis of cave ventilation was performed within the Velká Ondrášova Cave, a crevice-type cave in the Outer Western Carpathians, Czechia. Long-term temperature recording, airflow tracing within the cave, and a total of ...

Sulfur Dioxide From The Atmospheric Chemistry Experiment Satellite, Doug Cameron

College of Sciences Posters

The version 4.0 dataset from the Atmospheric Chemistry Experiment – Fourier Transform Spectrometer (ACE-FTS) on SCISAT, released in March of 2019, has sulfur dioxide (SO₂) volume mixing ratio (VMR) profiles as a routine data product. From this dataset, global SO₂ distributions between the altitudes of 10.5 km and 23.5 km are analyzed. The global distribution of all SO₂ VMR data by altitude is broken down into 30° and 5° latitude zones. Seasonality of the global SO₂ distribution is explored. Volcanic SO₂ plumes are isolated in the dataset and compared with extinction data from ...

Geochemical Tracers Of Arctic Ocean Processes: A Study Of Gallium, Barium, And Vanadium, Laura M. Whitmore

Dissertations

The Arctic Ocean is linked to the global oceans and climate through its connectivity with the North Atlantic Ocean and the regional thermohaline deep water formation sites. It’s also a region undergoing rapid environmental change. To inform the community of potential changes in geochemical and biogeochemical cycles, this dissertation addresses three dissolved geochemical tracers (gallium, barium, and vanadium) as indicators of Arctic Ocean processes. Gallium is tested as a replacement for nutrient-type tracers in an effort to deconvolve Pacific and Atlantic derived waters in the Arctic Ocean basins. These water masses carry different heat and salt content and can ...

Atmospheric Contrail Detection With A Deep Learning Algorithm, Nasir Siddiqui

Student Research, Papers, and Creative Works

Aircraft contrail emission is widely believed to be a contributing factor to global climate change. We have used machine learning techniques on images containing contrails in hopes of being able to identify those which contain contrails and those that do not. The developed algorithm processes data on contrail characteristics as captured by long-term image records. Images collected by the United States Deparment of Energy’s Atmospheric Radiation Management user facility(ARM) were used to train a deep convolutional neural network for the purpose of this contrail classification. The neural network model was trained with 1600 images taken by the Total ...