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Pakistan, India And The Indus River Basin, Muquadas Ilyas

Dissertations and Theses

Water is a fundamental need of all living things. The right to clean water is classified as a human right under United Nations Resolution 64/292.As such it is the responsibility of governments to ensure its citizens are not deprived of this essential resource. In doing so, effective water management is crucial to provide clean water that is accessible to everyone regardless of any challenges such as geographical constraints or political disputes. This thesis explores the water management efforts of Pakistan and India. These countries are facing a water crisis, whereby numerous citizens have died due to dehydration and diseases contracted …

Advancing The Accuracy Of Watershed Analysis Across Diverse Hydrometeorological And Geologic Regimes Via Classification And Analysis Of Gpm-Imerg Products, Jake M. Longenecker

Dissertations and Theses

The analysis and protection of watersheds, along with spring water resources, depend on the accurate identification of catchments. Building on previous research that correlated spring hydrographs with high-resolution, satellite-based Global Precipitation Measurement – Integrated Multi-satellitE Retrievals for GPM (GPM-IMERG) data, I improve the speed and accuracy of catchment identification and hydrodynamic characterization via an enhanced Empirically Constrained Hydrologic Operation (ECHO) algorithm. This research (1) establishes optimal parameter inputs for the algorithm to enable reliable identification of source point-locations, (2) removes human in-the-loop processing, and thus reduce potential operator bias, and (3) explores the potential for using a limited dataset of …

Sea Surface Temperatures And Vertical Wind Shear As Precursors To Tropical Cyclone Activity In The Caribbean And An Expanding Main Developing Region, Keneshia Hibbert

Dissertations and Theses

Sea surface temperatures and vertical wind shear are essential to tropical cyclone formation. TCs need warm SSTs and low shear for genesis. Increasing SSTs and VWS changes influence storm development. This work analyzes SST and VWS trends for the Caribbean, surrounding region, and the Atlantic hurricane main developing region from 1982 to 2020. Storm intensity increases significantly during this period. Annual and seasonal trends show regional SSTs in the MDR are warming annually (0.0219°C yr^-1) and per season (0.0280°C yr^-1). Simultaneously, VWS decreases during the late rainfall season at 0.0556m/s yr^-1 in the MDR and …

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …

A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir

Dissertations and Theses

Street flooding is problematic in urban areas, where impervious surfaces, such as concrete, brick, and asphalt prevail, impeding the infiltration of water into the ground. During rain events, water ponds and rise to levels that cause considerable economic damage and physical harm. The main goal of this dissertation is to develop novel approaches toward the comprehension of urban flood risk using data science techniques on crowd-sourced data. This is accomplished by developing a series of data-driven models to identify flood factors of significance and localized areas of flood vulnerability in New York City (NYC). First, the infrastructural (catch basin clogs, …

Investigating The Effect Of Electrolyte Concentration And Charging Protocol On Materials Utilization In Rechargeable Zinc Manganese Dioxide Batteries, Snehal H. Kolhekar

Dissertations and Theses

Achieving a highly cyclable, high energy density battery with MnO₂ cathodes encounters many obstacles. Chief among these is the inability of the widely-used γ-MnO₂ polymorph to retain its structural integrity when cycled to near full one-electron discharge capacity, which is about 280mAh/g for commercially available electrolytic manganese dioxide (EMD). In this one-electron range, discharge occurs by proton insertion producing Mn⁺³ which then reverts to γ-MnO₂ on charging. In the first part of the thesis, we investigate the root cause of failure of MnO₂ cathodes under deep cycling in the one-electron discharge range and establish a …

Analysis Of Uncertainty In Hydrometeorological Ensemble Forecasts, Carolien N. Mossel

Dissertations and Theses

Ensemble hydrometeorological forecasting has great potential for improving flood predictions and use in water management systems, however, the amount of data used and created with an ensemble forecast requires a careful and intentional approach to understand how useful and skillful the forecast is. The NOAA National Water Model (NWM) was run using downscaled NOAA Global Ensemble Forecast System (GEFS) meteorological forcings for the 2016-2017 wet season (October-March) in California to create an 11-member hydrologic forecast ensemble. To evaluate the performance of these ensemble forecasts, we chose to study streamflow sites within Sonoma County, California, a rain-dominated region which includes the …

Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang

Dissertations and Theses

The contemporary hydrosystems of the United States involve a complex combination of natural and modified basins in the presence of changing climate and anthropogenic impacts. An enhanced understanding of the interdependence between climate forcings, human-induced interventions, and water balance in both natural and modified basins are essential for developing reliable and resilient hydrosystems and for better water resources management. In response, this dissertation focuses on investigating the hydroclimatology of natural and modified basins across the contiguous United States. It has three research objectives: (1) to explain flow alterations due to anthropogenic activities, especially dam operations, in modified basins and understand …

Long Term Nutrient And Chlorophyll A Dynamics Across Long Island Sound And Impacts On Dissolved Oxygen Conditions Within The Western Sound (1991-2019), Sherry Perreira

Dissertations and Theses

Nitrogen overload, eutrophication, and hypoxia have been challenging and persistent water quality problems in Long Island Sound (LIS) over the past decades with major impacts on commercial industries, ecology, and recreational activities in the region. Recognizing these problems, the EPA enforced three phases of the Clean Water Act (CWA) to reduce nitrogen loads in an effort to improve this important estuary. This study examines how nitrogen (NH₃, NO_x & TDN), chlorophyll a (CHLA), and dissolved oxygen (DO) concentrations changed in LIS over the past 30 years, in response to water quality regulations as well as changes in …

On The Improvements Of Boundary-Layer Representation For High Resolution Weather Forecasting In Costal-Urban Environments, David Melecio-Vazquez

Dissertations and Theses

As large urban centers around the world become more densely populated, the global conversion from natural to man-made land surfaces will only increase. These land-use changes affect the urban surface energy budget which in turn changes the structure of the planetary boundary layer (PBL) above. With current high-performance computing systems, meteorological and built environment information can be better utilized to quantify the anthropogenic effects of these modifications. Although these systems have improved forecasting near-surface weather conditions, a comprehensive approach to represent urban impacts on the PBL is still limited. Improved PBL representation can lead to better weather and climate forecasts, …

Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro

Dissertations and Theses

Extreme heat events are becoming more frequent and intense in most large cities. Built-up surfaces also limit cooling mechanisms, leading to warmer conditions in cities, a phenomenon called the Urban Heat Island (UHI). This presents major challenges to reduce adverse health effects of hot weather, particularly in vulnerable populations like the elderly and low-income communities. Here we explore the overall impacts of increasing air conditioning (AC) system adoption in residences as an adaptive measure to reduce human health risks under heat waves, with New York City (NYC) as a case study. This study uses AC adoption data from the 2017 …

Ecosystem Health In Guánica Bay And La Parguera, Puerto Rico: Remote Sensing Of Ocean Color And Metal Analysis Of Coral Tissue And Surficial Sediments, Jahnelle Howe

Dissertations and Theses

Guánica Bay is an estuary located in southwest Puerto Rico, with a coral reef ecosystem at its periphery. This ecosystem is affected by sediments, nutrients, and contaminants from the watershed through the Bay and into the offshore water. This project evaluates Guánica Bay and La Parguera coastal areas through remote sensing and chemical analysis to assess coastal ecosystem health. The concentration of metals in two coral species and their associated surface sediments was were analyzed by X-ray fluorescence (XRF) and Direct Mercury Analyzer (DMA- 80). Ocean color remote sensing was used to estimate nutrient inputs and phytoplankton biomass through chlorophyll- …

Macro - And Microstructure Evaluation And Field Applications Of Concrete With Recycled Glass Pozzolan, Marija Krstic

Dissertations and Theses

Concrete is the most used material in the world, second only to water. Conventional concrete is produced with Portland cement (PC). The production of cement is an energy intensive operation that has raised significant environmental concerns, since one ton of cement generates an equal ton of CO₂. In the USA about 90 million tons of cement are used annually, with 3 million tons used in New York. Most contemporary concrete applications for buildings and infrastructure use high-performance concrete (HPC) mixtures which are produced by replacing a percentage of cement with supplementary cementitious materials (SCMs), consisting mainly of fly-ash …

Toward Closing The Urban Surface Energy Balance Using Satellite Remote Sensing, Joshua Hrisko

Dissertations and Theses

The energy exchanges at the Earth’s surface are responsible for many of the processes that govern weather, climate, human health, and energy use. This exchange, commonly known as the surface energy balance (SEB), determines the near-surface thermodynamic state by partitioning the available energy into surface fluxes. The net all-wave radiation is often the primary energy source, while the heat storage and sensible and latent heat fluxes account for the majority of energy distributed elsewhere. While the SEB of various natural environments(trees, crops, soils) has been well-observed and modeled, the urban surface energy balance remains elusive. This is due to the …

Comparison Of Gold Extraction Yields By Cyanide Treatment Vs. Bioleaching Procedure, Yilman Steven Pineda

Dissertations and Theses

Samples from the tailings of the Picacho mine in California were leached using NaCN and native bacteria, Alcaligenes faecalis, in column experiments to compare the gold recovery yields in the effluents. Four columns were treated with a different liquid: water, bacteria, NaCN and a mixture of cyanide and bacteria. After they were leached the effluents were analyzed to determine gold yields. During experiment I the total Au recovered in the effluent in the column treated with bacteria was only 10.09% less than those treated with cyanide (C2) and 81.7% more than the control. In experiment II, Au values measured were …

Towards Improving Accuracy And Interpretability Of Deep Learning Based On Satellite Image Classification, Yamile Patino Vargas

Dissertations and Theses

ABSTRACT

The study of satellite images provides a way to monitor changes in the surface of the Earth and the atmosphere. Convolutional Neural Networks (CNN) have shown accurate results in solving practical problems in multiple fields. Some of the more recognized fields using CNNs are satellite imagery processing, medicine, communication, transportation, and computer vision. Despite the success of CNNs, there remains a need to explain the network predictions further and understand what the network is determining as valuable information.

There are several frameworks and methodologies developed to explain how CNNs predict outputs and what their internal representations are [1, 4, …

Hydroclimate Drivers And Atmospheric Dynamics Of Floods, Nasser Najibi

Dissertations and Theses

Our preliminary survey showed that most of the recent flood-related studies did not formally explain the physical mechanisms of long-duration and large-peak flood events that can evoke substantial damages to properties and infrastructure systems. These studies also fell short of fully assessing the interactions of coupled ocean-atmosphere and land dynamics which are capable of forcing substantial changes to the flood attributes by governing the exceeding surface flow regimes and moisture source-sink relationships at the spatiotemporal scales important for risk management. This dissertation advances the understanding of the variability in flood duration, peak, volume, and timing at the regional to the …

Convective Transport Of Tropical Marine Boundary Layer Species Into The Upper Troposphere And Relation To Species Lifetime: In Situ Measurements And Global Model Simulation, Sofia M. Chelpon

Dissertations and Theses

This study investigates the influence of tropical deep convection on distribution of trace gasses in the tropical upper troposphere (UT) using data from the Convective Transport of Active Species in the Tropics (CONTRAST) Experiment conducted over the tropical western Pacific during January and February of 2014. Fifty-five chemical species measured during the CONTRAST campaign are analyzed with lifetimes ranging from less than a day to several years. The vertical profiles of these species suggest that they fall into three main groups delineated by their lifetime: 1) very long-lived trace gases demonstrating a nearly constant vertical structure, 2) intermediate lifetime species …

Revised Distributional Estimates For The Recently Discovered Olinguito (Bassaricyon Neblina), Using Museum And Science Records, Beth E. Gerstner

Dissertations and Theses

In the context of global change, a necessary first step for the conservation of species is gaining a good understanding of their distributional limits. This is especially important for biodiversity hotspots with high endemism such as the Northern Andes. The olinguito (Procyonidae: Bassaricyon neblina) is a recently described, medium-sized carnivoran found in Northern Andean cloud forests. A preliminary distributional model was published along with the original description, and I here provide revised distributional estimates using updated locality records and more current ENM methods. I build ecological niche models in Maxent using occurrence data (georeferenced museum records and citizen science-derived photo-vouchers) …

Adsorption Of Antibiotics By Vermiculite, Mosa J. Ferdous

Dissertations and Theses

The occurrence of residual antibiotics in the environment has been a worldwide issue and warrants the development of inexpensive yet effective methods for antibiotics removal from contaminated water. In this thesis work, the adsorption of four antibiotics, namely chlorotetracycline (CTC), oxytetracycline (OTC), ofloxacin (OFL), and enrofloxacin (ENR), onto natural vermiculite has been studied using batch (static) and column (dynamic) adsorption techniques. The Langmuir and Freundlich isotherm models were initially used to explain the adsorption processes. The separation factor (RL) values derived from the Langmuir model and the 1/n values derived from Freundlich model in the present investigation were less than …

Integrated Hydrologic Land Surface State Climate Indicators, Brian Lamb

Dissertations and Theses

No abstract provided.

Intra- And Inter-Seasonal Variability Of Supra-Glacial 1 Streams And Lakes Over The West Greenland Ice Sheet 2 From High-Resolution Satellite Optical Data, Michael Gregory Brown

Dissertations and Theses

The Greenland ice sheet (GrIS) is one of the largest glacial ice masses on Earth, second only to the Antarctic ice sheet. The surface hydrology of the GrIS plays a crucial role on the surface energy and mass balance budgets of the ice sheet as a whole. Surface water, known as supra-glacial water, is seasonally found in the ablation zone and feeds the en-glacial and sub-glacial hydrological environments of the ice sheet. The spatial distribution of surface streams is poorly understood and their temporal variability is (to our knowledge) unknown. One of the reasons for the lack of knowledge on …

Comparative Phylogeography Of Glassfrogs (Vitreorama) Endemic To The Brazilian Altantic Rainforest, Zoe Spanos

Dissertations and Theses

The Brazilian Atlantic Forest harbors one of the most diverse faunas of the world, including 2-3% of all known vertebrate species. Understanding the role of both climate and landscape in shaping current biodiversity patterns has been the focus of many recent phylogeographic studies. Here I explore multiple factors thought to have impacted the generation of local diversity in the Brazilian Atlantic Forest (AF) using two montane, stream-associated species of glassfrogs – V. eurygnatha and V. uranoscopa. I integrate species distribution modeling, path analysis, and molecular data to test the role of climatic stability, rivers, mountain chains, and geographic distance in …