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Climate change

2019

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Full-Text Articles in Physical Sciences and Mathematics

On The Frontlines - The Fishermen Of Ibrahim Hyderi, Muhammad Haris Aslam Khan Dec 2019

On The Frontlines - The Fishermen Of Ibrahim Hyderi, Muhammad Haris Aslam Khan

MSJ Capstone Projects

Climate change has become a matter of recent debate for much of the world. According to a report published by a German watch, a non-governmental organization, in 2019, Pakistan among the five countries at severe risk of climate change disasters.

During the last two decades, Pakistan saw more than 141 extreme climatic catastrophes. Only in 2016, more than 566 people died due to these conditions.

A report published by Asian Development Bank in 2017 indicates Pakistan’s climate change profile. It states that more than 1,600 people have lost their lives in the super flood of 2010 alone. A loss of …


Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell Dec 2019

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …


The Rockaway Project - Townes, Diara Jepris D. Townes Dec 2019

The Rockaway Project - Townes, Diara Jepris D. Townes

Capstones

The Rockaway Project is a story-driven website that provides information on the government response to Superstorm Sandy recovery on the Rockaway peninsula in Queens, New York. Dozens of climate resiliency projects have been delayed or remain unfinished, despite millions of dollars in funding and six years of promises. The website hosts audio, visual and digital content, gathered through interviews and data collection.

Link to capstone project: https://www.youtube.com/watch?v=fAq2BeR4bS0&t=1s


Modeling Lake Temperature Response To Climate Change In The Alaskan Arctic, Thomas Balkcom Dec 2019

Modeling Lake Temperature Response To Climate Change In The Alaskan Arctic, Thomas Balkcom

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This thesis study focuses on simulating lake temperature and ice duration for four lakes at the Arctic Long-Term Ecological Research site, near the Toolik Field Station in Alaska. Model projections were driven by the representative global climate model outputs under different carbon emission scenarios. Results show that my simple lake model can reproduce historical lake temperature and ice duration observations, indicating the reliability of the model for future projections. Model projections show that JuneSeptember lake temperatures would increase by 4.3-5.8 °C from the historical period with most progressive carbon emission scenarios, but by 0.7-2.2 °C in the conservative scenarios. Results …


Developing, Adopting, And Executing 100% Net-Renewable Electricity Resolutions At The Local Level, Emily E. Skill Dec 2019

Developing, Adopting, And Executing 100% Net-Renewable Electricity Resolutions At The Local Level, Emily E. Skill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the absence of national leadership on climate policy, municipalities are adopting resolutions to reduce their carbon footprint and transition to clean energy. However, what leads to successful adoption of these resolutions and how to effectively implement climate goals at the community level needs further exploration. To investigate these questions, this thesis examines the resolutions adopted in Salt Lake City, Park City, and Moab, Utah to transition to 100% renewable electricity by 2032. Data was collected through documents, such as city reports and newspapers, and interviews with government officials, city staff, and community members involved with the resolution process. A …


Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina Nov 2019

Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina

Electronic Theses and Dissertations

Lake Auburn, Maine, USA, is a historically unproductive lake that has experienced multiple algal blooms since 2011. The lake is the water supply source for a population of ~60,000. We modeled past temperature, and concentrations of dissolved oxygen (DO) and phosphorus (P) in Lake Auburn by considering the watershed and internal contributions of P as well as atmospheric factors, and predicted the change in lake water quality in response to future climate and land-use changes. A stream hydrology and P-loading model (SimplyP) was used to generate input from two major tributaries into a lake model (MyLake) to simulate physical mixing, …


A Numerical Investigation Of Sediment Dynamics In The Northern Gulf Of Mexico In Connection With Hurricanes, Fluid Mud, Climate Change, And Biogeochemical Cycling, Zhengchen Zang Oct 2019

A Numerical Investigation Of Sediment Dynamics In The Northern Gulf Of Mexico In Connection With Hurricanes, Fluid Mud, Climate Change, And Biogeochemical Cycling, Zhengchen Zang

LSU Doctoral Dissertations

Sediment transport and deposition in marginal seas is jointly controlled by many factors including hydrodynamics, fluvial inputs, and the characteristics of sediment particles. This dissertation study employs the coupled ocean-atmosphere-wave-and-sediment transport modeling system (COAWST) to investigate the mechanism of sediment transport in the northern Gulf of Mexico (nGoM) on different temporal scales, as well as its interaction with biogeochemical processes.

First of all, a three-way coupled (atmosphere-wave-ocean) hurricane model reproduced the hydro- and sediment dynamics during hurricane Gustav (2008). Intensive alongshore and offshore currents were simulated on the eastern/western sectors of hurricane track, respectively. High suspended sediment concentration (SSC) was …


The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev Sep 2019

The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and using …


An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp Jul 2019

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …


An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp Jul 2019

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …


The Evolution Of The El Niño-Southern Oscillation And Tropical Pacific Climate Across The Last Deglaciation, Ryan Hunter Glaubke Jul 2019

The Evolution Of The El Niño-Southern Oscillation And Tropical Pacific Climate Across The Last Deglaciation, Ryan Hunter Glaubke

OES Theses and Dissertations

The El Niño – Southern Oscillation (ENSO) is the largest interannual component of Earth’s climate system, capable of exerting significant influence over global climate patterns that affect communities around the globe. Nevertheless, a comprehensive understanding of the ENSO system and its relationship to tropical Pacific climate dynamics remains unclear. Although new paleoceanographic proxies have shown promise in in their ability to constrain past ENSO change, little is known about how ENSO varied in response to millennial-scale climate events over the last 25,000 years. Here, I present new records of tropical Pacific mean state and ENSO variability over the last 25,000 …


Probing The Relationship Of Cyanobacterial Toxins And Reactive Oxygen Species Within The Natural World, Meagan Lachelle Smith Jul 2019

Probing The Relationship Of Cyanobacterial Toxins And Reactive Oxygen Species Within The Natural World, Meagan Lachelle Smith

Theses and Dissertations

The occurrence of harmful algal blooms (HABs) and their impacts on human health and the economy are only expected to worsen in the coming years, mainly due to climate change related factors. In Lake Wateree, SC, a HAB of the species Lyngbya wollei, has been persistent for more than 10 years and is estimated to occupy 60 - 90 km of shoreline. This natural laboratory provided and continues to provide a unique window into the chemistry and microbial ecology of HABs. Work in this dissertation was directed at answering a critical question: are biomass-to-toxin ratios constant in HABs? Initial …


The Spectroscopic And Computational Exploration Of Sulfur Hydrogen Bonding, Andrew Yoonkeun Lee Jun 2019

The Spectroscopic And Computational Exploration Of Sulfur Hydrogen Bonding, Andrew Yoonkeun Lee

Honors Projects

Hydrogen bonds are a subset of non-covalent interactions that occur between X-H — Y, in which X and Y are the very electronegative atoms. In our research, we examine the more unconventional hydrogen bond-like interactions of thiol (SH) containing molecules using vapor-phase infrared (IR) spectroscopy and ab initio computational chemistry. When the SH hydrogen bond donor complexes to a hydrogen bond acceptor, a red shift of the SH stretching mode emerges. An anharmonic oscillator local mode model is applied to the ethanethiol-trimethylamine dimer, and we determine that any IR evidence of dimerization in our experiment is likely obscured by the …


Facilitating Greenhouse Gas Reduction And Climate Change Adaptation Within The Coastal Zone: A Policy Analysis For The California Coastal Commission, Nicole Young May 2019

Facilitating Greenhouse Gas Reduction And Climate Change Adaptation Within The Coastal Zone: A Policy Analysis For The California Coastal Commission, Nicole Young

Master's Theses

California is already experiencing impacts to its coastline due to climate change, and more severe impacts are anticipated if greenhouse gas emissions continue to rise. These climate change impacts are especially strong within the California coastal zone, which falls under the jurisdiction of the California Coastal Commission. The Commission has a history of rigorous environmental protection and is committed to protecting California’s coast through proactive planning and regulation, however they will need to initiate coastal policies with ambitious targets to facilitate effective climate change adaptation and mitigation. This study analyzed existing California climate policies and Coastal Commission policies to identify …


Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias May 2019

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …


Ethical Implications Of Population Growth And Reduction, Tiana Sepahpour May 2019

Ethical Implications Of Population Growth And Reduction, Tiana Sepahpour

Student Theses 2015-Present

No abstract provided.


A Conceptual Modeling Framework For Hydrological Ecosystem Services And Its Application To The Impacts Of Climate Change And Urban Expansion, Feng Pan May 2019

A Conceptual Modeling Framework For Hydrological Ecosystem Services And Its Application To The Impacts Of Climate Change And Urban Expansion, Feng Pan

Theses and Dissertations

Ecosystem services (ESs) are used as intermediates for researchers, stakeholders, and the public to understand and deal with the current environmental situation and problems, and ESs-related studies have drawn increasing attention. The quantitative assessments of ESs to calculate how much the ecosystem can benefit human beings and society, are still under development. Hydrological ESs, a subset of ESs that is related to water bodies and the surrounding environment, carry several challenges and opportunities for both hydrological and ESs modeling. Specifically, new quantitative tools with the capability to simulate explicit spatial and temporal scales are desired, and such tools should be …


Ecological And Economic Implications Of Increased Storm Frequency And Severity For Boreal Lakes, Kathryn Warner May 2019

Ecological And Economic Implications Of Increased Storm Frequency And Severity For Boreal Lakes, Kathryn Warner

Electronic Theses and Dissertations

In boreal regions, increased precipitation events have been linked to increased concentrations of dissolved organic carbon (DOC), however less is known about the extent and implications of these events on lakes. We assessed the effects of precipitation events on six drinking water lakes in Maine, USA to better understand how DOC concentration and quality change in response to precipitation events. Our results revealed three types of responses: (1) an initial spike in DOC concentrations and quality metrics; (2) a sustained increase in DOC concentrations and quality metrics and; (3) no change during all sampling periods. Lake residence time was a …


Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys May 2019

Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys

Graduate Theses and Dissertations

A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …


An Examination Of Seasonal Shifts In Climate And Visitation, And Perspectives On Seasonal Shifts And Climate Adaptation Strategies In Tourism And Recreation Businesses For Moab, Utah, Elizabeth Cook May 2019

An Examination Of Seasonal Shifts In Climate And Visitation, And Perspectives On Seasonal Shifts And Climate Adaptation Strategies In Tourism And Recreation Businesses For Moab, Utah, Elizabeth Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The city of Moab, an outdoor recreation hub in eastern Utah, has been encountering both shifts in the seasonality of visitation, and increases in tourist visitation, even with summer temperatures above the normal high. Tourism research describing the effects of climate change on the outdoor recreation industry has focused on winter, snow-dependent activities, while studies in Moab city have focused on the economic value of outdoor recreational activities. Few studies have described the relationship between seasonal tourism and climate change for arid desert locations. The purpose of this study is to describe how the tourism and recreation industry in Moab, …


Future Changes Of Hydroclimatic Extremes In Western North America Using A Large Ensemble: The Role Of Internal Variability, Mohammad Hasan Mahmoudi Apr 2019

Future Changes Of Hydroclimatic Extremes In Western North America Using A Large Ensemble: The Role Of Internal Variability, Mohammad Hasan Mahmoudi

Electronic Thesis and Dissertation Repository

Increases in the intensity and frequency of extreme events in Western North America (WNA) can cause significant socioeconomic problems and threaten existing infrastructure. In this study we analyze the impacts of climate change on hydroclimatic extremes and assess the role of internal variability over WNA, which collectively drain an area of about 1 million km2. We used gridded observations and downscaled precipitation, maximum and minimum temperature from seven General Circulation Models (GCMs) that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and a large ensemble of CanESM2 model simulations (CanESM2-LE; 50 members) for this analysis. Spatial …


Adjudication And The Adaptive Capacity Of Pecan Farmers In The Lower Rio Grande, Daniel R. Beene Apr 2019

Adjudication And The Adaptive Capacity Of Pecan Farmers In The Lower Rio Grande, Daniel R. Beene

Geography ETDs

Despite growing uncertainty of water availability in the future and popular understandings of water conservation in agriculture, a growing number of farmers in the Lower Rio Grande Basin are rapidly transitioning to pecan orchards, a long-term and highly water-dependent crop. Drivers of landscape change can be environmental, historic, socioeconomic, or institutional. Adaptation to change is understood as responses to external stimuli and is limited to a threshold by which an actor can meet their goals. Much of the current scholarship focuses on a given population’s adaptive capacity toward global climate change, however, most water policy in the western United States …


Changes In Spring Arrival Times: Climate Change And The Phenology Of Spring Bird Migration, Aaron Svedlow Apr 2019

Changes In Spring Arrival Times: Climate Change And The Phenology Of Spring Bird Migration, Aaron Svedlow

Student Scholarship

Climate change and weather affect the phenology of bird migration; however, specific climatological factors associated with these observed effects have only recently been described. The relationship between local, regional, and global climate patterns and avian migration are increasingly important to understand due to the widespread, and potentially negative, implications (such as reduced fecundity) of rapid human induced climate change on bird populations. Migratory birds are under selective pressure to arrive at breeding areas at the optimal time to set up nesting territories and exploit seasonally abundant food resources, and because climate change has the potential to occur more rapidly than …


Characterization Of Psychromonas Aquimarina, A New Model Organism For Climate Change, Carrie Carpenter Apr 2019

Characterization Of Psychromonas Aquimarina, A New Model Organism For Climate Change, Carrie Carpenter

Experiential Learning Projects

The current increase of average global temperature puts 25 to 35 percent of plant and animal species at an increased risk of extinction (Climate Change, 2018). Changing any environmental factor, such as increasing growth temperature, can significantly impact any organisms’ ability to survive. Because of the diversity of organisms on the planet, it is not feasible to study how each individually might adapt, but rather it is more efficient to study select organisms. This research focuses on a psychrophilic bacterium, Psychromonas aquimarina, which can survive in colder regions where most bacteria would not. This bacterium was chosen because climate change …


The Ecological Impacts Of Climate Change In Hot Regions – Are Hawksbill Turtles Living Above Their Optimum Temperature In The Uae?, Obaid Ali Alshamsi Apr 2019

The Ecological Impacts Of Climate Change In Hot Regions – Are Hawksbill Turtles Living Above Their Optimum Temperature In The Uae?, Obaid Ali Alshamsi

Theses

It is getting warmer throughout the world but it is not getting warmer by the same amount in all regions, leading to speculations that the biggest impact will be the impact on species living in the hot regions is widely assumed to be slight in comparison to the temperate and higher latitude regions. Temperature changes in hot regions are smaller, but it may be that the species in those regions have reached their optimum temperatures. In which case the effects of even a small temperature increase could be steeply negative. To test this thoroughly in terms of demographic parameters I …


Rising Temperatures In Hot Regions – How Many Species Would Be Able To Survive?, Sounak Ghosh Apr 2019

Rising Temperatures In Hot Regions – How Many Species Would Be Able To Survive?, Sounak Ghosh

Biology Theses

Temperatures are rising throughout the world but not uniformly. Different latitudes have varying degrees of temperature rise and the most rapid changes are happening in the higher northern latitudes while only minor warming is taking place in the hot tropical regions. It has been widely assumed that the biggest ecological impacts will be seen in the cooler northern latitudes and that the impacts in hot tropical regions will be much smaller. However, if species in hot regions are already close to their thermal limits and if species in cold regions are far below them, it may be that small temperature …


Wildfires In The Northeastern United States: Evaluating Fire Occurrence And Risk In The Past, Present, And Future, Daniel R. Miller Mar 2019

Wildfires In The Northeastern United States: Evaluating Fire Occurrence And Risk In The Past, Present, And Future, Daniel R. Miller

Doctoral Dissertations

Climate change is one of the most complex and challenging issues facing the world today. A changing climate will affect humankind in many ways and alter our physical environment, presenting ethical challenges in how we respond. The impact of climate change will likely be exacerbated in heavily populated regions of the planet, such as the Northeastern United States (NEUS). The NEUS is comprised of complex, sprawling urban centers and rural regions, both of which are vital to the economic and cultural character of the region. Furthermore, both urban and rural areas in the NEUS contain communities that have been historically …


Snowmelt Detection On Alpine Glaciers Using Synthetic Aperture Radar Time Series, Corey Scher Jan 2019

Snowmelt Detection On Alpine Glaciers Using Synthetic Aperture Radar Time Series, Corey Scher

Dissertations and Theses

Hindu Kush Himalayan (HKH) glaciers serve as some of the most sensitive indicators of changes in global climate. These glaciers shape the hydrologic dynamics of river systems supplying freshwater to over 2 billion people throughout Asia and regulate the geochemistry of sensitive aquatic alpine ecosystems. As snowmelt onsets sooner, lasts longer, and snowfields retreat due to increases in global temperature, the hydrologic dynamics of catchments draining HKH threaten to change the availability of surface freshwater resources for nearly one fifth of the global population, disturb sensitive aquatic habitat, and precipitate hazards associated with glacier wasting. Informed planning and decision-making around …


Effects Of Halogen Bonding And Nir Tuning Of Dyes For Dye-Sensitized Solar Cells, Alexandra Baumann Jan 2019

Effects Of Halogen Bonding And Nir Tuning Of Dyes For Dye-Sensitized Solar Cells, Alexandra Baumann

Electronic Theses and Dissertations

With current energy demands being met through the utilization of energy sources such as petroleum, natural gas, and coal, the non-renewable nature of these sources will eventually approach depletion as world wide energy consumption increases yearly. As a result the need for a renewable energy alternative has become imminent. One appealing alternative that has gained considerable attention since its development due to a low cost and a high solar to electric conversion efficiency are dye-sensitized solar cells (DSCs). This dissertation describes efforts to design and synthesize improved organic dyes utilizing three analogous methods: first, through decreasing non-productive pathways such as …


Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman Jan 2019

Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman

WWU Graduate School Collection

The Stillaguamish River in northwest Washington State, USA, provides water resources to local agriculture, industry and First Nations Tribes, and provides crucial habitat for several endangered species of salmonids. The watershed experiences a mild maritime climate and high relief, with rain and snowmelt dominating the streamflow. In anticipation of shifts in snowpack, streamflow, and stream temperature, I use projected global climate scenarios and numerical models to examine future climatic variability on streamflow and stream temperatures in the snow-melt dominated North Fork of the Stillaguamish River. I calibrated the physically based Distributed Hydrology Soil Vegetation Model (DHSVM) and River Basin Model …