Doctor of Philosophy, The Ohio State University, 2009, Atmospheric Sciences

The Odden event is a dominant mode of the Arctic sea ice variability, which is very important for the Arctic climate. The Odden sea ice feature extends northeastward from the Arctic pack ice of the east Greenland Sea during winter and spring, typically covering an area between 8°W and 5°E, and between 73° and 77°N. The key causes and forcing of Odden sea ice variability in the atmosphere and ocean is examined using the Community Sea Ice Model5.0 (CSIM5) within a Slab Ocean Model (SOM) called the M configuration of Community Climate System Model3.0 (CCSM3) provided by the National Center for Atmospheric Research (NCAR). A 26 year control run is made with the T62 NCEP/NCAR Reanalysis (NNR) atmospheric data from 1979 – 2004, and the simulated northern Atlantic sea ice is compared with that from the Hadley Center Sea ice and Sea Surface Temperature (HadISST) observational dataset in order to evaluate the model's capabilities. The control run sea ice data were subjected to a rotated principal component analysis (RPCA) that revealed a component (#3) mode of variability that exhibited Odden-like variability similar to that obtained in observational data. To further investigate the single or multiple effects from the atmospheric and oceanic parameters associating with the Odden sea ice, 18 experiments are conducted with the NNR and a 1° x 1° Simple Ocean Data Assimilation (SODA) for the atmospheric and oceanic forcing, respectively. In one set of experiments the atmosphere and ocean model are run simultaneously in efforts to simulate the Odden while other experiments evaluate Odden forcing of individual atmospheric parameters with other parameter forcing being held in a non-Odden state. Model forcing data for Odden ice conditions are from 1997 (January – December) while those from 1994 are used as the forcing for non-Odden conditions, in keeping with observational studies. Results show that the model sea ice concentration (SIC) and ice thickness exhibit large variability i (open full item for complete abstract)

Master of Science (MS), Ohio University, 2021, Geography (Arts and Sciences)

Due to the global impacts of Antarctic sea ice and the changing climate, it is important to understand what is influencing Antarctic sea ice variability in a historical context. This is especially true since observations of Antarctic sea ice only begin around 1979. To investigate what is influencing Antarctic sea ice in a longer context, this study generated, evaluated, and analyzed new reconstructions of Antarctic sea ice extent (SIE) through statistical relationships with other long-term datasets available throughout the 20th century. A principal component regression technique that has been proven successful in other Antarctic climate reconstructions was employed in this study, using pressure and temperature observations across the Southern Hemisphere in conjunction with indices of large-scale climate variability known to influence Antarctic SIE. Ultimately, this study was conducted to determine if Antarctic SIE reconstructions are a skillful measure for understanding historical Antarctic sea ice trends and variability throughout the 20th century. The newly generated reconstructions demonstrate that skillful seasonal (extending back to 1905) and monthly (extending back to 1957) sea ice reconstructions can be produced. In comparison, the monthly reconstructions outperformed the seasonal reconstructions based on various assessments (including an independent validation approach), although both sets of reconstructions improved historical sea ice extent knowledge well beyond the use climatological mean. Although shorter in duration due to the inclusion of nearby Antarctic temperature and pressure (which begin near 1957), the monthly reconstructions also allowed for a broader analysis on sea ice extent for month-to-month variations and were useful for monitoring changes in the reconstruction skill performance that could not be seen on a seasonal level. While these new reconstructions unlock new information previously unknown about early 20th century Antarctic sea ice e (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2024, Geodetic Science

Present-day sea-level change under an increasingly warmer Earth is a significant and consequential problem adversely impacting humankind in our generation and beyond. In 2020, an estimated 896 million people, or 11% of the global population, reside in the world's coastal regions, which are already at risk of land losses from rapid sea-level rise. By 2050, over a billion people will be exposed to risks from coastal climate hazards (Glavovic et al., 2022). With the advent of satellite altimetry, continuous global sea-level measurements have been available since 1991. However, the measurements remain too short to accurately determine rapid sea-level rise in light of the detecting oceanic signals with periodicities up to decadal or longer. For estimating longer-term, global spatiotemporal sea-level change at regional scales, empirical sea-level reconstruction is known to be such a methodology. By combining shorter-term (30 years) satellite altimetry sea-level and sparsely distributed but long-term (>50 years) tide gauges records, the reconstruction method is aimed at modeling adequate long-period signals globally and at regional scales. However, contemporary reconstruction methods plausibly have considerable temporal mismatches between the satellite altimetry and the tide gauge sea-level records, resulting in errors in separation and quantification of climate episode patterns at multi-decadal or longer time scales, and rapid sea-level rise (trends and potential accelerated sea-level rise) regionally over the global oceans. Our scientific objective is to quantify the respective roles of identified climate episode patterns induced present-day sea-level changes towards understanding the internal oceanic variability forcing mechanisms under an increasingly warmer Earth. First, we processed global tide gauge sea-level records using statistical methods to minimize the impact of time series data gaps. This resulted in 263 out of 287 selected long-term tide gauge reco (open full item for complete abstract)

Master of Science (MS), Ohio University, 2023, Geography (Arts and Sciences)

Changes in Earth's cryosphere, including sea ice in both polar regions, often result in amplified climate-related impacts through positive feedback loops, making it crucial to understand how and why the cryosphere is evolving now and into the future. Observations of Antarctic sea ice are comparably short as the records have only been reliably observed since the satellite era began in 1979. Prior to the satellite era, limited data sources on Antarctic sea ice are available, including various reconstructions and discrete information in ship logbooks from expeditions and commercial vessels written in the remarks sections. This research aims to further understand how independent early sources of information can be used to evaluate the skill of seasonal Antarctic sea ice extent reconstructions (Fogt et al. 2022). Ship logbook observations of sea ice are extremely valuable because they are able to give insight into where the ice edge was prior to satellite measurement in 1979. As this is a new area of research, little is yet known on what potential data have been recovered. Not only is it important to know what data are available, but also if the ship logbooks are reliable enough to be used to evaluate Antarctic sea ice extent reconstructions. This research compiled a list of available ship logbooks at Ohio University, only a handful of which were able to be digitized in time for this project. The latitudes from the ship logbooks of the ice edge show to be within an acceptable range of the latitudes of the sea ice from reconstructions (on average within 3°), indicating the skill of the sea ice extent reconstructions, spatially and temporally, is good prior to 1979. The Antarctic sea ice extent reconstructions were also compared with estimates of early twentieth century sea ice extent from coupled climate models in terms of the ranges of variability and linear trends. Overall, the variability in the sea ice, both temporally and spatially, are sim (open full item for complete abstract)

Master of Science (MS), Wright State University, 2022, Earth and Environmental Sciences

Methylmercury (MeHg) is a neurotoxin that bioaccumulates to potentially harmful concentrations in Arctic marine wildlife and in those that consume them. Monitoring and modeling MeHg bioaccumulation and biogeochemical cycling in the ocean requires understanding of the mechanisms behind net mercury (Hg) methylation. The key functional gene for Hg methylation, hgcAB, is widely distributed throughout ocean basins and spans multiple microbial phyla. While multiple microbially-mediated anaerobic pathways for Hg methylation are known, in the ocean, the majority of hgcA homologs have been found in oxic subsurface waters, in contrast to other ecosystems. In particular, microaerophilic Nitrospina, a genera of nitrite-oxidizing bacteria containing a hgcA-like sequence, has been proposed as a potentially important Hg methylator in upper ocean waters. The objective of this work was therefore to examine the potential of nitrifiers as Hg methylators and quantify total Hg and MeHg across three Arctic Seas (the Gulf of Alaska, the Bering Sea and the Chukchi Sea) in regions where Nitrospina are likely present. In Spring 2021, samples for Hg analysis were obtained from all sites with a trace metal clean rosette. Hg methylation rates were quantified in concert with nitrification rates using on-board incubation experiments with Hg and 15NH4+ stable isotope additions. A significant correlation between Hg methylation and nitrification was observed across all sites, with the strongest correlation in the Chukchi Sea. Nitrospina-specific hgcA-like genes were detected at all sites. This study, linking Hg methylation and nitrification in oxic seawater, furthers understanding of MeHg cycling in these high latitude waters and the ocean in general. Furthermore, these studies inform predictions of how climate and human interactions could influence MeHg concentrations in the Arctic region in the future.

Doctor of Philosophy, The Ohio State University, 2021, Chemistry

Marine aqueous interfaces constitute one of the most prevalent surfaces in the biosphere and the atmosphere, and understanding the physicochemical processes at these interfaces is of significant importance for informing Earth system models. In the following chapters, surfactant organization and morphology on aqueous solutions of high ionic strength are explored as a proxy for the organic films coating sea spray aerosol (SSA) surfaces and the sea surface microlayer (SSML). First, a proxy film mixture comprised of the saturated fatty acids myristic acid (C14), palmitic acid (C16), and stearic acid (C18) was selected to study sea spray aerosol film morphology as a function of atmospheric acidification. The nascent SSA proxy film is fluid and flexible, whereas the acidified film is more rigid; as a result, the nascent SSA proxy film folds upon collapse, and the acidified film fractionates into three-dimensional structures with compression. Next, the influence of surfactant organization on one-dimensional surface-sensitive infrared spectroscopy was examined. Decreasing intermolecular distances between a soluble perfluorooctanoic acid film and an insoluble arachidic acid (C20) monolayer cause vibrational exciton delocalization across the surfactants, manifesting in alkyl and fluoroalkyl signal reduction and deviations from the Beer-Lambert law. The aqueous electrolyte composition in part modulates surfactant intermolecular spacing, affecting the extent of vibrational delocalization. Consequently, quantitative analyses involving alkyl and fluoroalkyl one dimensional vibrational peak intensities must be approached with caution. Lastly, surfactant-mediated cooperative adsorption of a soluble polysaccharide to a proxy sea surface microlayer is studied. Seawater divalent cations facilitate ionic bridges between the marine-relevant, anionic polysaccharide alginate and a partially deprotonated palmitic acid monolayer. Calcium promotes the strongest bridging interactions, and pal (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2019, Earth Sciences

Tide gauges record relative sea level (RSL), i.e. the vertical position of the sea surface relative to the adjacent land mass or relative to the seafloor under the gauge. A tide gauge cannot distinguish between a rise in sea level or subsidence of the land or seawall or pier that supports the gauge. Absolute sea level (ASL) refers to the level or height of the sea surface stated in some standard geodetic reference frame, e.g. ITRF2008. Since satellite altimeters make a geometrical measurement of sea level, this constitutes a determination of ASL. Satellite altimeters suffer from instrumental drift and thus need to be calibrated using tide gauges. This requires us to estimate the rate of RSL change at each tide gauge and convert this into an estimate of the rate of ASL change. This is done using a GPS station located at or near the tide gauge, since it can measure the vertical velocity of the lithosphere – often referred to as vertical land motion, VLM – which allows us to exploit the relationship ASL = RSL + VLM. This goal has motivated geodesists to build dozens of continuous GPS (or CGPS) stations near tide gauges – an agenda sometimes referred to as the CGPS@TG agenda. Unfortunately, a significant fraction of all long-lived tide gauges – especially those in the Pacific - have also recorded non-steady land motion caused by earthquakes. Rather than simply delete such datasets from the agenda, this thesis explores a new analytical method, based on the concept of a geodetic station trajectory model, that allows us to compute RSL and ASL rates even at tide gauges affected by regional earthquakes. We illustrate this method using two tide gauges (PAGO and UPOL) and three GPS stations (ASPA, SAMO and FALE) located in the Samoan islands of the Southwest Pacific. In addition to managing the impact of large regional earthquakes, we also seek new approaches to reducing noise in RSL rate estimates by suppressing the higher frequency sea level changes associated with ocean (open full item for complete abstract)

BA, Oberlin College, 2017, Politics

This thesis analyzes the different relationships between cities and states in sea level rise adaptation. To determine the most effective governing structure, I compare my own categorical framework to an evaluative framework from the Georgetown Climate Center. I find that my category of limited-constraint autonomy is most effective for sea level rise adaptation.

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Doctor of Philosophy, The Ohio State University, 1977, Graduate School

Doctor of Philosophy, The Ohio State University, 2012, Electrical and Computer Engineering

Range-resolved interferometric phase and Doppler spectra are two subjects of interest with regard to the retrieval of sea surface height profiles from coherent marine radar measurements. The studies of this dissertation attempt to improve understanding of the properties and associated measurement errors of these quantities through the use of numerically simulated low-grazing-angle backscatter data. In the first part of the dissertation, studies of the interferometric phase are described. Backscattered fields computed using the method of moments for one dimensional ocean-like surface profiles are used to examine statistical properties of the single-look interferometric phase estimator, in order to investigate the applicability of standard expectations for height retrieval accuracy in this problem. The results show that shadowing and multipath propagation effects cause errors in interferometric phase estimation beyond those caused by speckle effects alone. In addition, the decorrelation between the fields received at two antennas is found to be impacted by shadowing and multipath propagation effects, making standard models for this quantity less applicable as well. These results show that modeling the expected performance of interferometric sea surface height retrieval approaches at low grazing angles is difficult. The second part of the dissertation involves studies of the range-resolved Doppler spectra at low-grazing-angles. Backscattered fields are computed for a single realization of a one-dimensional ocean-like surface profile as the realization evolves in time. Transformation into the range-Doppler domain enables examination of properties of the resulting Doppler spectra (for both HH and VV polarizations) and their relationship to properties of the surface profile. In general, a strong correspondence between the long wave orbital velocity of the surface and the Doppler centroid frequency is observed for visible portions of the surface, as well as some evidence (open full item for complete abstract)

Master of Science, The Ohio State University, 2011, Civil Engineering

There is a large uncertainty around the rates of evaporation from desert enclosed seas, and in particular the Red Sea. The Gulf of Aqaba is long and narrow and is partially isolated from the Red Sea and the Indian Ocean by shallow and narrow straits. The long fringing reef of the Red Sea has a large economic importance to the region's tourism. In the northern part of the Red Sea, vertical mixing of the water column, which is driven by evaporation, supplies nutrients to the shallow water and, at high levels, results in favorable conditions for algae over corals, and thus, will lead to the destruction of corals. The local weather and sea surface temperature are also affected by the rates of evaporation. There are two compounding phenomena that complicate the estimation of evaporation rate in this region: (1) Although the wind is mostly oriented along the long axis of the narrow Gulf, advection of water vapor towards the dry desert surrounding the Red Sea may account for large amounts of water. (2) In the summer, the mean sea surface temperature is colder than the warm, dry desert air, leading to a thin stable boundary layer above the sea that may suppress evaporation. Atmospheric and oceanic models of the Red Sea area have run into difficulties in estimating the evaporation rates. There are very few locations where the temperature and humidity are measured routinely. Direct measurements of evaporation or on-shore advection of water vapor were not previously conducted in this region. In March 2009 we set up two eddy flux towers at the Inter-University Institute for Marine Science in Eilat, Israel, at the north western shore of the Gulf of Aqaba. We conducted measurements of water vapor wind and other meteorological conditions. We used the eddy-covariance technique to calculate the mass balance of water in the atmosphere above the coral lagoon near the shore. Our measurements show that a combination of advection toward land and stability conditions of the boundary laye (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2006, Atmospheric Sciences

The upper ocean significantly influences tropical cyclone structure and intensity. These effects, however, are not well understood mostly due to a lack of oceanic and atmospheric boundary layer observations within the inner-core region. This study relates ocean-atmosphere energy exchange processes to mid-to-upper tropospheric latent heating using mesoscale inner-core convective burst events. A global survey of convective burst events in tropical cyclones from the year 1999 – 2001 was constructed. This study shows that 80% of tropical cyclones have at least one convective burst event and that convective burst events usually occur during the intensification phase of the storm life cycle. Latent and sensible heat flux estimates and a measure of upper-ocean energy utilization were calculated for the inner-core (<.5° radius) and the near-core (.5° - 1° radius). This study found that tropical cyclones generally utilize only about 8% of the total enthalpy flux available from the ocean/atmosphere boundary layer. Storms with convective bursts utilize more energy from the ocean (11%) than storms with no convective burst (2%). Sea-air fluxes are greatly enhanced (doubled) during convective burst time periods. These along-track ocean-atmosphere analyses was compared to vertical profiles of atmospheric latent heating calculated using a combined active and passive TRMM PR and TMI retrieval algorithm. Results show strong positive space and time correlations between ocean-air fluxes and mid-upper tropospheric latent heating. Additionally, the 30 storms analyzed were categorized by the presence or absence of convective burst events during the storm lifecycle. Composite atmospheric latent heating profiles constructed for each group show a two-fold release in energy for the storms with convective burst events compared to storms with no convective burst event. Finally, seven case studies are presented which attempt to resolve the upscale energy cascade of the tropical cyclone with a co (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2005, Geodetic Science and Surveying

Sea level rise has been widely recognized as a measurable signal and as one of the consequences of possible anthropogenic (human-induced) effect of global climate change. The small rate of sea level rise signal, at 1-2 mm/yr during the last century [Church et al., 2001], could only be partially explained by a number of competing geophysical processes, each of which is a complex process within the Earth-atmosphere-ocean-cryosphere-hydrosphere system. In particular, the observed 20th Century sea level rise rate of 1.84±0.35 mm/yr [Douglas, 2001; Peltier, 2001] could not explain up to one half of the predicted 20th Century global sea level rise based on the IPCC TAR estimate of 1.1 mm/yr (0.6 mm/yr from melt water from ice sheets and glaciers, and 0.5 mm/yr from steric effect in the ocean) [Church et al., 2001] and remains an enigma [Munk, 2002]. The quest to resolve the controversy [Meier and Wahr, 2002] and to further understanding sea level change [Chao et al., 2002] is well underway during the current IPCC Fourth Assessment Report (FAR), 2003–2007. In this study, we provide a determination of the 20th Century global sea level rise, the associated error budgets, and the quantifications of the various geophysical sources of the observed sea level rise, using data and physical models. We analyzed significant geographical variations of the global sea level including those caused by steric component (heat and salinity) in the ocean, and the self-gravitational signal as a result of ice sheet melt including effect of glacial isostatic adjustment (GIA) since the Pleistocene. Altimeter and selected tide gauge sea level data have been used for the 20th Century sea level determination, accounting for relative biases between the altimeters, effects of sea level corresponding to oceanic thermal expansion, vertical motions affecting tide gauge measurements, self gravitations, and barotropic ocean response. This study is also characterized by the roles of the polar ocean in the g (open full item for complete abstract)

Master of Arts (MA), Ohio University, 2012, Political Science (Arts and Sciences)

China has over the past several years begun to implement a new Maritime Law Enforcement (MLE) strategy in the South China Sea. This new MLE strategy utilizes vessels from China's rapidly expanding MLE agencies, reinforced by PLA naval and other military assets, to assert the country's claims against other Southeast Asian claimants, particularly Vietnam and the Philippines. A noticeably dramatic increase in the number of incidents at sea in disputed areas has occurred alongside the implementation of this new strategy, escalating tensions to dangerous levels. China's MLE strategy is an evolution in thinking from previous PLA doctrine, and is in many ways the operationalized extension of concepts such as 'legal warfare'. The employment of the strategy not only risks upsetting China's relations with its neighbouring countries, but may also be suggestive of an emerging contest between China and the US over international norms at sea.

Ph.D., Antioch University, 2024, Antioch New England: Environmental Studies

There is no quiet way to churn water. Noise pollution caused by ships is increasing in the Arctic Ocean as sea ice melts, creating more open channels for vessels. This study provides a glimpse into the sources and balance of sounds in a portion of the Arctic Ocean soundscape surrounding the Norwegian archipelago of Svalbard. Characterization of the soundscape provides essential data as the region quickly transforms. This study also considers human perceptions of underwater ocean noise and its impacts in the region, and it reviews current ocean policy, suggesting mitigation strategies and ways forward. Before the rapid development of industry, prominent sounds in this underwater soundscape came from geological and biological sources. As vessel traffic increases, primary sound sources may be shifting from wind to ship noise. Sea ice extent has decreased in all months and in almost all regions of the Arctic, impacting Arctic marine mammals (AMMs) as their rapidly contracting habitat fills with unfamiliar anthropogenic noise. Noise in the ocean's underwater soundscape degrades acoustic habitat. This study helps fill a gap in knowledge that has limited our understanding of how much underwater noise the eleven AMMs are exposed to and its effects, especially in consideration of the unique hearing and communication capabilities of each species. AMMs spend much of their lives in deep darkness and have evolved to depend on sound as their principal sense. They rely on sensory cues to learn and thrive in their environments. Hydrophones were deployed at 44 locations between 13 °E and 19 °E and 69 °N and 79 °N in April 2023. Wind, waves, and ice (geophony) dominated the soundscape's acoustic signature in remote locations, while human-caused sounds (anthrophony) were significant near Arctic shipping routes, fishing areas, and in fjords. Marine mammal vocalizations were detected near the ice edge, at fjord mouths, and in fjords. Collecting and interpreting data that help explain th (open full item for complete abstract)

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2024, American Culture Studies

Monstrous animals occupied a prominent role in the imaginations of the 18th and early 19th century European settlers in what would become the United States of America. This preoccupation with monsters among early Americans is clearly reflected in the life and career of Thomas Jefferson. A close examination of Jefferson's Notes on the State of Virginia (1785), scientific papers prepared for the American Philosophical Society, documentation relating to the Louisiana Purchase, financing of the Louis and Clark Expedition, and personal correspondence all reveal a persistent obsession with living mastodons, giant moose, and colossal lions among other curious creatures. As a key American representative of the western intellectual tradition known as the Enlightenment, Jefferson's conviction that the North American interior harbored such monstrous forms of undiscovered animal life may seem counterintuitive as one would presume Jefferson would be nothing but skeptical of the reality of fantastic beasts. However, Jefferson saw evidence for the reality of such hitherto unclassified species of megafauna in an amalgamation of fragmentary fossil remains, euhemerist interpretations of Indigenous American legends, and tall tales told by early pioneers; the same type of ephemeral evidence marshaled by today's cryptozoologists to prove the existence of such creatures as Bigfoot and the Loch Ness Monster. It is with this later observation in mind that this dissertation seeks to reframe Jefferson as a pioneering cryptozoologist while also considering the important role which cryptozoological monster lore has played in the formation of American culture.

Doctor of Philosophy, The Ohio State University, 2023, Materials Science and Engineering

Rising concerns related to fuel consumption and greenhouse emissions are being addressed by the automotive industry through vehicle lightweighting. Hence to meet the stringent requirements for lightweighting, conventional steel body parts are being replaced with Al alloys, Mg alloys and composite materials. However, the use of dissimilar materials together poses a serious threat of galvanic corrosion leading to accelerated degradation of galvanically coupled body parts. Aiming to develop the automotive closure panels using carbon fiber reinforced plastics (CFRP) inner and an outer aluminum alloy sheet to replace what is now an all-steel design, corrosion studies are performed to determine effective qualification of materials. In the first part of this project, CFRP materials of two types, named as twill and random, coupled with aluminum alloys (AA) 6111 and 6022 in all combinations, are subjected to a Ford laboratory accelerated cyclic corrosion test (CETP: 00.00-L-467) and on-road testing with the help of OSU campus buses for a year. The ability of the laboratory accelerated test to predict the on-road corrosion behavior is assessed by comparing the material volume loss determined using optical profilometer, microscopic images of corroded regions, and measurements of galvanic currents of the coupons exposed to the cyclic test. Analysis of the test results indicated that the coupon combination AA6111 and CFRP-random exhibits the highest corrosion susceptibility whereas AA6022 coupled with CFRP-twill is least susceptible to galvanic corrosion among the combinations used in this study. In the second part of the study, electrochemical behavioral differences between CFRP-twill and -random contributing to the differences in activities when coupled to AA6xxx are evaluated. For this, a copper deposition technique was developed to quantify the extent of electrochemical activity and identify the exact location of electrochemically active sites on the CFRP. Optimization (open full item for complete abstract)

Master of Science (MS), Ohio University, 2023, Geography (Arts and Sciences)

As climate change continues unabated, understanding Earth's complex climate system remains critical. The Antarctic climate system is a crucial part of this system, and the sea ice surrounding the continent is an incredibly important element. With the largest change in albedo on Earth, Antarctic sea ice is responsible for reflecting solar radiation from the region. As seen in the Arctic as a result of climate change, without sea ice this solar radiation is absorbed by the low albedo ocean causing warming and further melt of sea ice in a positive feedback loop. Antarctic sea has not responded in the same way as the Arctic. Observations of Antarctic sea ice date back to October 1978 and have shown an overall increase in sea ice. A sudden decline in sea ice extent in 2016 was an unexpected turn of events, and a new record low extent in February 2023 has further complicated this. Due to the short records of Antarctic sea ice extent and the complex nature of the regional climate system, it is difficult to isolate the impacts of climate change in the region. To expand these short records, reconstructions have been utilized. Monthly reconstructions, based on observational temperature and pressure data, were created in order to extend this record to 1957. These reconstructions were analyzed in this study in order to determine their skill and understand how Antarctic sea ice extent has changed through the 1957-2020 period. This was done for the total sea ice extent around the Antarctic continent as well as the Bellingshausen-Amundsen, East Antarctic, King Hakon, Ross, and Weddell regions. The reconstructions were analyzed using correlation, regression, and comparison of means statistical methods in order to evaluate relationships between Antarctic climate data and sea ice extent, relationships between modes of climate variability and sea ice extent, changes in the seasonal cycle of sea ice extent, and trends in sea ice extent. It was of interest to det (open full item for complete abstract)

Bachelor of Science (BS), Ohio University, 2023, Geography

Comprehensive planning is a tool commonly used by municipalities in the United States for to express long term goals regarding climate change adaptation. As climate change is a politically polarizing topic in our country, this study aimed to look at the ways in which conservative leaning and liberal leaning cities address climate change in these plans. To do this, I rely on a policy evaluation framework and a key word count. By using both of these strategies, I am able to see how well cities planned for climate adaptation based on their political affiliation, and also how often they used climate related terms.