Climate Commons^™

Tree Ring Dating Of The Ficklin-Imboden Log Structures, Powhatan Historic State Park, Arkansas, Kaylee R. Mcadoo, David W. Stahle

Journal of the Arkansas Academy of Science

Powhatan Historic State Park in Powhatan, Arkansas preserves and interprets five historical structures from 19^th century Arkansas, including the Ficklin-Imboden Log House. This structure, which is actually two separate log buildings with uncertain construction dates and functions, is believed to be the earliest surviving structure at Powhatan State Park and is on the National Register of Historic Places. Powhatan State Park contracted with the University of Arkansas Tree-Ring Laboratory to develop a more accurate dating and interpretation of the log structures.

Dendrochronology (tree-ring dating) was used to determine the true felling dates of logs in both buildings. Core specimens …

Observation-Driven Estimation Of The Spatial Variability Of 20th Century Sea Level Rise, B. D. Hamlington, A. Burgos, P. R. Thompson, F. W. Landerer, C. G. Piecuch, S. Adhikari, L. Caron, J. T. Reager, E. R. Ivins

OES Faculty Publications

Over the past two decades, sea level measurements made by satellites have given clear indications of both global and regional sea level rise. Numerous studies have sought to leverage the modern satellite record and available historic sea level data provided by tide gauges to estimate past sea level rise, leading to several estimates for the 20^th century trend in global mean sea level in the range between 1 and 2 mm/yr. On regional scales, few attempts have been made to estimate trends over the same time period. This is due largely to the inhomogeneity and quality of the tide …

Expected Limits On The Ocean Acidification Buffering Potential Of A Temperate Seagrass Meadow, David A. Koweek, R. C. Zimmerman, Kathryn M. Hewett, Brian Gaylord, Sarah N. Giddings, Kerry J. Nickols, Jennifer L. Ruesink, John J. Stachowicz, Yuichiro Takeshita, Ken Caldeira

OES Faculty Publications

Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global‐scale solution to ocean acidification remains rapid reduction in CO₂ emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of seagrass meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from seagrasses. We developed a biogeochemical box model to …

Future Nuisance Flooding In Norfolk, Va, From Astronomical Tides And Annual To Decadal Internal Climate Variability, A. G. Burgos, B. D. Hamlington, P. R. Thompson, R. D. Ray

OES Faculty Publications

Increasing sea level rise will lead to more instances of nuisance flooding along the Virginia coastline in the coming decades, causing road closures and deteriorating infrastructure. These minor flood events can be caused by astronomical tides alone, in addition to internal climate variability on annual to decadal timescales. An assessment of nuisance flooding from these two effects is presented up until the year 2050 for Norfolk, Virginia. The analysis of water levels indicates that nuisance flooding from tides alone in conjunction with a medium-high sea level scenario will result in flooding beginning in 2030 with frequency increasing thereafter. The addition …

Climate-Change-Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters, G. T. Mitchum

CCPO Publications

Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change-driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y². Coupled with the average climate-change-driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections.

Stratospheric And Tropospheric Contributions To The Poleward Energy Flux Across 70°N And 65°S In The Merra-2 And Cesm, Christopher Cardinale

Legacy Theses & Dissertations (2009 - 2024)

The flux of moist static energy (MSE) across 70°N and 65°S plays a key role in the energy budget and climate of the polar regions. This flux, which provides respectively 98 W m⁻² and 91 W m⁻² heating of the northern and southern polar caps, is usually studied from a vertically integrated perspective. Its vertical structure is examined using the NASA-MERRA-2 reanalysis to compute monthly fluxes of sensible, latent and potential energy across 70°N and 65°S for the period 1980-2016. The flux is bimodal, with peaks in the lower troposphere and in the middle stratosphere, and is near zero at …

Understanding The Relationship Between Winter Hawaii Precipitation And North Pacific Climate Variability For Past And Present Climate Conditions, Siyu Li

Legacy Theses & Dissertations (2009 - 2024)

Kona lows (KLs) are a type of seasonal cut-off cyclones in the North Pacific around the Hawaiian Islands during the cold season month (Oct.-Apr.). KLs are important for the annual rainfall budget of the Hawaiian Islands. This study investigates what controls the winter precipitation variability over the Hawaiian Islands in the present-day climate and within a long-term paleoclimate simulation. ERA-interim data from 1979-2014 are used for the present-day analysis of the large-scale circulation. The potential vorticity is used as a measure of extratropical synoptic activity. The Hawaii Rainfall Index is from the Rainfall Atlas of Hawaii (seasonal means, 1920-2012). For …

Projected Changes In Climate, Elevation-Dependent Warming, And Extreme Events Over Continental Ecuador For The Period 2041-2070, Oscar Chimborazo

Legacy Theses & Dissertations (2009 - 2024)

The climate over Ecuador is complex due to several interacting factors, such as its location at the equator, the Andean topography, and several modes of internal variability, including the El Niño–Southern Oscillation (ENSO), affecting the region. In addition, the rapid increase in greenhouse gas concentrations will continue to affect both the mean state and climate variability in Ecuador over the coming decades. Hence, a thorough understanding of both natural and anthropogenic forcings and how they combine to influence Ecuadorian climate is a necessity for decision-making and implementation of adequate adaptation measures. However, the lack of observational data, both in space …

Urban Areas In Coastal Zones, Richard C. Dawson, M. Shah Alam Khan, Vivien Gornitz, Maria Fernanda Lemos, Larry Atkinson, Julie Pullen, Juan Camilo Osorio, Lindsay Usher, Cynthia Rosenzweig (Ed.), William Solecki (Ed.), Patricia Romero-Lankao (Ed.), Shagun Mehrotra (Ed.), Shobhakar Dhakal (Ed.), Somayya Ali Ibrahim (Ed.)

CCPO Publications

[First Paragraph] Coastal cities have been subjected to extreme weather events since the onset of urbanization. Climatic change, in particular sea level rise, coupled with rapid urban development are amplifying the challenge of managing risks to coastal cities. Moreover, urban expansion and changes and intensification in land use further pressure sensitive coastal environments through pollution and habitat loss.

Long-Term Changes In Extreme Air Pollution Meteorology And Implications For Air Quality, Pei Hou

Dissertations, Master's Theses and Master's Reports

Extreme air pollution meteorology, such as heat waves, temperature inversions, and atmospheric stagnation episodes, can significantly affect air quality. In this study, we analyze their long-term trends and the potential impacts on air quality. The significant increasing trends for the occurrences of extreme meteorological events in 1951-2010 are identified with the reanalysis data, especially over the continental regions. A statistical analysis combining air quality data and meteorological data indicates strong sensitivities of air quality, including both average air pollutant concentrations and high pollution episodes, to extreme meteorological events. Results also show significant seasonal and spatial variations in the sensitivity of …

Investigation Of Microphysical Properties Of Laboratory And Atmospheric Clouds Using Digital In-Line Holography, Neel Desai

Dissertations, Master's Theses and Master's Reports

In this study, we attempt to perform in-cloud measurements, both in the laboratory using the Michigan Tech $\Pi$-chamber and in the atmosphere via the CSET field campaign. Atmospheric turbulence is believed to play a critical role in the growth, development and dissipation of clouds and it is important to study its effect in order to better understand and predict cloud properties such as albedo and lifetime. We use digital in-line holography to measure the effect of turbulence on cloud microphysical properties such as variations in droplet number concentration and droplet or ice particle size. In the first half, we study …

Wildfire Emissions In The Context Of Global Change And The Implications For Mercury Pollution, Aditya Kumar

Dissertations, Master's Theses and Master's Reports

Wildfires are episodic disturbances that exert a significant influence on the Earth system. They emit substantial amounts of atmospheric pollutants, which can impact atmospheric chemistry/composition and the Earth’s climate at the global and regional scales. This work presents a collection of studies aimed at better estimating wildfire emissions of atmospheric pollutants, quantifying their impacts on remote ecosystems and determining the implications of 2000s-2050s global environmental change (land use/land cover, climate) for wildfire emissions following the Intergovernmental Panel on Climate Change (IPCC) A1B socioeconomic scenario.

A global fire emissions model is developed to compile global wildfire emission inventories for major atmospheric …

Ocean Circulation Causes Strong Variability In The Mid-Atlantic Bight Nitrogen Budget, Marjorie A.M. Friedrichs, Pierre St-Laurent, Yongjin Xiao, Eileen Hofmann, Kimberly Hyde, Antonio Mannino, Raymond G. Najjar, Diego A. Narváez, Sergio R. Signorini, Hanqin Tian, John Wilkin, Yuanzhi Yao, Jianhong Xue

CCPO Publications

Understanding of nitrogen cycling on continental shelves, a critical component of global nutrient cycling, is hampered by limited observations compared to the strong variability on a wide range of time and space scales. Numerical models have the potential to partially alleviate this issue by filling spatiotemporal data gaps and hence resolving annual area-integrated nutrient fluxes. In this study, a three-dimensional biogeochemical-circulation model was implemented to simulate the Mid-Atlantic Bight (MAB) nitrogen budget. Model results demonstrate that, on average, MAB net community production (NCP) was positive (+0.27 Tg N/year), indicating net autotrophy. Interannual variability in NCP was strong, with annual values …

Comparison Of Various Mean Field Formulations For Retrieving Refractive Indices Of Aerosol Particles Containing Inclusions, Kristin S. Dooley, Jessica Deyoung

Journal of the Arkansas Academy of Science

Application of effective medium approximation (EMA) methods to two-component systems are presented. Systems studied are composed of water, sulfate, soot, and dust as these are commonly encountered atmospheric aerosol components. Atmospheric models often employ EMAs to include internally mixed aerosols without the computational burden of exact theory. In the current work, several types of mixing rules (Maxwell-Garnet, Bruggeman, and coherent potential approximation) have been applied to various two-component internally mixed particles at 550 nm using volume fractions of the minor component below 0.1. As expected, results show that the formulations tested produce very similar effective refractive indices indicating that electric …

Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle

All Master's Theses

Low summer river base flow places a strain on natural and economic resources of the Eastern Cascades. A major contributor to stream flow in this region is snow pack which has declined over the past few decades because of a warming climate. In addition, glacial runoff, which contributes significantly to base flow in summer dry periods, will diminish from glacial recession. However, rock glaciers, because their internal ice (i.e., permafrost) is insulated by an outer debris layer, react slowly to climate change, thus acting as sinks for ice and liquid water storage in mountain environments. This study utilized ground penetrating …

Global Sea-Level Budget 1993-Present, Wcrp Global Sea Level Budget Group, Benjamin Hamlington

CCPO Publications

Global mean sea level is an integral of changes occurring in the climate system in response to unforced climate variability as well as natural and anthropogenic forcing factors. Its temporal evolution allows changes (e.g.,acceleration) to be detected in one or more components. Study of the sea-level budget provides constraints on missing or poorly known contributions, such as the unsurveyed deep ocean or the still uncertain land water component. In the context of the World Climate Research Programme Grand Challenge entitled "Regional Sea Level and Coastal Impacts", an international effort involving the sea-level community worldwide has been recently initiated with the …

The Increased Risk Of Flooding In Hampton Roads: On The Roles Of Sea Level Rise, Storm Surges, Hurricanes, And The Gulf Stream, Tal Ezer

CCPO Publications

The impact of sea level rise on increased tidal flooding and storm surges in the Hampton Roads region is demonstrated, using ~90 years of water level measurements in Norfolk, Virginia. Impacts from offshore storms and variations in the Gulf Stream (GS) are discussed as well, in view of recent studies that show that weakening in the flow of the GS (daily, interannually, or decadal) is often related to elevated water levels along the U.S. East Coast. Two types of impacts from hurricanes on flooding in Hampton Roads are demonstrated here. One type is when a hurricane like Isabel (2003) makes …

Public Participation During Reactive, Crisis-Driven Drought Planning Versus Proactive, Preparedness Planning, C. Anna Ulaszewski

Walden Dissertations and Doctoral Studies

Droughts are occurring globally and should be recognized as a global issue and drought planning should use a proactive approach on the part of the world community. However, much drought planning, even in developed and highly developed countries, is reactive and programs are often poorly coordinated sometimes with unforeseen negative consequences for marginalized and disenfranchised populations. Literature pertaining to planning strategy for existing, drought crises is nominal and often contributes to patterns of reactiveness and resulting inequity. To gain a better understanding of crisis-driven planning and the participatory process, this gap was viewed through the lenses of institutional analysis and …

Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D’Amato, Tiphaine Després, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Álvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Thomas Kitzberger, Dominik Kulakowski, David Lindenmayer, Akira S. Mori, Jörg Müller, Juan Paritsis, George L.W. Perry, Scott L. Stephens, Miroslav Svoboda, Monica G. Turner, Thomas T. Veblen, Rupert Seidl

Geography

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and …

Unraveling Phytoplankton Community Dynamics In The Northern Chukchi Sea Under Sea-Ice-Covered And Sea-Ice-Free Conditions, A. R. Neeley, L. A. Harris, K. E. Frey

Geography

The timing of sea ice retreat, light availability, and sea surface stratification largely control the phytoplankton community composition in the Chukchi Sea. This region is experiencing a significant warming trend, an overall decrease in sea ice cover, and a documented decline in annual sea ice persistence and thickness over the past several decades. The consequences of earlier seasonal sea ice retreat and a longer sea-ice-free season on phytoplankton community composition warrant investigation. We applied multivariate statistical techniques to elucidate the mechanisms that relate environmental variables to phytoplankton community composition in the Chukchi Sea using data collected during a single field …

(Un)Frozen Spaces: Exploring The Role Of Sea Ice In The Marine Socio-Legal Spaces Of The Bering And Beaufort Seas, Kristen L. Shake, Karen E. Frey, Deborah G. Martin, Philip E. Steinberg

Geography

Sea ice is a dynamic physical element of the greater Arctic marine system, one that has myriad connections to human systems on a variety of spatial and temporal scales. Changes to the spatial extent of sea ice simultaneously permits and endangers maritime operations, as well as impacts current debates over maritime boundaries, presenting an interesting challenge for international law. Sea ice is not a stationary object; it moves through time and space in response to the physical forces of wind, ocean currents, and heating. It has a tangible, material and substantive role in contestations over territory, resources and marine boundaries …

Collaborative Strategies For Sea Level Rise Adaptation In Hampton Roads, Virginia, Carol Considine, Emily Steinhilber

Engineering Technology Faculty Publications

[Introduction] The Hampton Roads region is located in southeastern Virginia where the Chesapeake Bay meets the Atlantic Ocean. The region includes seventeen municipal governments and has a large federal government presence with 26 federal agencies represented (See Figure 1). The region has a population that exceeds 1.7 million and is home to the deepest water harbor on the U.S. East Coast. Hampton Roads' economy is dependent on the local waterways and houses the world's largest naval facility, the sixth largest containerized cargo complex and supports a thriving shipbuilding and repair industry as well as a tourism industry. However, the region's …

Temporal Trends In Human Vulnerability To Excessive Heat, Scott C. Sheridan, Michael J. Allen

Political Science & Geography Faculty Publications

Over recent decades, studies have examined various morbidity and mortality outcomes associated with heat exposure. This review explores the collective knowledge of the temporal trends of heat on human health, with regard to the hypothesis that humans are less vulnerable to heat events presently than in the past. Using Web of Science and Scopus, the authors identified all peer-reviewed articles that contained keywords on human impact (e.g. mortality, morbidity) and meteorological component (e.g. heat, heatwave). After sorting, a total of 71 articles, both case studies and epidemiological studies, contained explicit assessments of temporal trends in human vulnerability, and thus were …

Climate Change And Eutrophication: A Short Review, Mohammad Nazari-Sharabian, Sajjad Ahmad, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

Water resources are vital not only for human beings but essentially all ecosystems. Human health is at risk if clean drinking water becomes contaminated. Water is also essential for agriculture, manufacturing, energy production and other diverse uses. Therefore, a changing climate and its potential effects put more pressure on water resources. Climate change may cause increased water demand as a result of rising temperatures and evaporation while decreasing water availability. On the other hand, extreme events as a result of climate change can increase surface runoff and flooding, deteriorating water quality as well. One effect is water eutrophication, which occurs …

Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Climate variability at global and regional scales is escalating with increased atmospheric carbon and is expected to magnify the intensity and duration of meteorological extremes, especially droughts. From the many environmental stresses that diminish crop production (e.g., soil salinity, frost, soil erosion) drought is one of the most prevalent. This study focuses on the sensitivity of three key crops produced in the northwestern United States to climatological anomalies, while controlling for attribution using anomalies in price. The study differs from similar studies in that we focus on variability in production which captures both yield (tonnes/ha) and cropping area (ha), as …

High Frequency Temperature Variability Reduces The Risk Of Coral Bleaching, Aryan Safaie, Nyssa J. Silbiger, Timothy R. Mcclanahan, Geno Pawlak, Daniel J. Barshis, James L. Hench, Gareth J. Williams, Kristen A. Davis

Biological Sciences Faculty Publications

Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in …

Going Negative: The Next Horizon In Climate Engineering Law, Tracy Hester, Michael B. Gerrard

Faculty Scholarship

As the global community struggles to turn the Paris Agreement’s commitments into meaningful emission reductions and the United States turbulently reverses its climate policies, the potential role of “negative emissions technologies” and other climate engineering approaches is drawing increasingly serious attention. These technologies are engineering on the grandest scale: climate engineering seeks to offset the effects of anthropogenic climate change by either altering the solar radiation reaching the earth’s surface or changing the composition of the atmosphere itself. Specifically, negative emissions technologies would directly remove greenhouse gases (GHGs) from the ambient air and help to remove accumulated atmospheric carbon dioxide …

Evaluation Of A Climate Change Training Program For Local Government Employees, Clara Kashar

Theses and Dissertations

A local government in South Florida launched a training program to improve employee engagement on climate change using best practices in adult learning and climate communication to bridge the gap between climate science and action in government operations. The purpose of this program evaluation was to determine whether that climate change development and training program for local government employees met its stated goals and objectives. This evaluation blended a component of Stufflebeam’s Context, Input, Process, Product (CIPP) model with Kirpatrick’s Four Levels model. To conduct the evaluation, the researcher used a mixed methods approach for analyzing both quantitative and qualitative …

Trends In Benthic Macrofaunal Populations, Seasonal Sea Ice Persistence, And Bottom Water Temperatures In The Bering Strait Region, Jacqueline M. Grebmeier, Karen E. Frey, Lee W. Cooper, Monika Kędra

Geography

Recent declines in sea ice extent and warming seawater temperatures in the Arctic have the potential to impact regional and pan-Arctic marine ecosystems. To investigate marine biological response to these key drivers and other environmental factors, we undertook a robust trend analysis of benthic macrofaunal populations and environmental drivers in the Bering Strait region. Our focus was on the waters of the northern Bering and southern Chukchi Seas, which are shallow (m) and seasonally productive, with strong pelagic-benthic coupling between water-column-derived organic matter and the seafloor. Studies indicate that both in situ production and advection of upstream phytodetritus support persistent …

Data Descriptor: Compilation Of Climate Data From Heterogeneous Networks Across The Hawaiian Islands, Ryan J. Longman, Thomas W. Giambelluca, Michael A. Nullet, Abby G. Frazier, Kevin Kodama, Shelley D. Crausbay, Paul D. Krushelnycky, Susan Cordell, Martyn P. Clark, Andy J. Newman, Jeffrey R. Arnold

Geography

Long-term, accurate observations of atmospheric phenomena are essential for a myriad of applications, including historic and future climate assessments, resource management, and infrastructure planning. In Hawai'i, climate data are available from individual researchers, local, State, and Federal agencies, and from large electronic repositories such as the National Centers for Environmental Information (NCEI). Researchers attempting to make use of available data are faced with a series of challenges that include: (1) identifying potential data sources; (2) acquiring data; (3) establishing data quality assurance and quality control (QA/QC) protocols; and (4) implementing robust gap filling techniques. This paper addresses these challenges by …