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Kuo, Chung-YenDetermination and characterization of 20th century global sea level rise
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 global sea level study, and addressing the question whether there is a detectable sea level rise acceleration during the last decade.

Committee:

C.K. Shum (Advisor)

Keywords:

SEA LEVEL; tide gauge; TOPEX/POSEIDON; thermosteric sea level

Eisendrath, EmmaMultilevel Governance in Sea Level Rise Adaptation: An Analysis of U.S. Cities
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.

Committee:

Swapna Pathak (Advisor); H.N. Hirsch (Committee Member); Ronald Kahn (Committee Member)

Subjects:

Environmental Management

Keywords:

climate change; sea level; sea level rise; policy; environmental policy; municipal governance; cities; federalism

Sun, JianGround-Based GNSS-Reflectometry Sea Level and Lake Ice Thickness Measurements
Doctor of Philosophy, The Ohio State University, 2017, Geodetic Science and Surveying
Rising sea levels, originated from global climate change, lead to increasing number of inhabitants exposed to catastrophe damages. Hence, monitoring and observing sea level and its variation are of great significance, especially for the population living in the coastal regions. Recently, the ground-based Global Navigation Satellite System Reflectometry (GNSS-R) technique has been developed and applied to measure coastal sea level and lake level, to complement contemporary methods such as tide gauges and satellite radar altimetry. Compared with conventional techniques of tide gauge, this GNSS-R altimetry is capable of measuring absolute or geocentric sea level, or lake level height without land vertical motion contaminations. Additionally, it behaves much better in the coastal regions than traditional pulse-limited radar altimetry. As a result, the GNSS-R altimetry technique can potentially mitigate the temporal and spatial deficiency of historical and current sea level records. A list of concisely stated study objectives is as follows: The GNSS-R altimetry operates in a bistatic radar configuration, and its forward-scattering signal that is an electromagnetic (EM) wave is impacted by surface scattering properties, in addition to other error sources such as media delay. As one of the primary error sources, the EM bias resulted from the lesser reflectivity of sea wave crests rather than troughs, results in the underestimation of sea level height. To model the EM bias, a numerical simulation was initially conducted using linear and nonlinear wave models. The modeling results confirmed that GNSS-R altimetry measurement EM bias increases with decreasing incidence angle and increasing wind speed, with a constant GNSS antenna height above the reflected sea surface. We used two realistic GNSS-R sea level measurements from two GPS sites located in the Gulf of Mexico for empirical EM bias modeling, which is a function of wind speed and the elevation angles along which GNSS reflected signals were collected by the GNSS antennae. We used the wind speed data to generate empirical GNSS-R EM bias models, which resulted in the improvement of the GNSS-R sea level accuracy. Also, the empirical EM bias models were shown to be more effective in improving GNSS-R sea level accuracy than the theoretical EM bias model. When the simulated and empirical models were applied to the original GNSS-R sea levels, it demonstrated that the RMS error decreased from ~7.3 cm to ~ 4.8 cm and ~3.4 cm, respectively. To comprehensively assess the accuracy of the in situ GNSS-R sea levels, two adjacent geodetic-quality GPS sites 30 m apart at Robinson Point, and the closest tide gauge 13-km away at Tacoma, Washington, were selected for our validation study. The GNSS-R sea level time series has an 8-year sea level data span. The consistency between two adjacent GNSS-R sea level time series was significantly closer than the cases between either of the GNSS-R sea level and tide gauge time series. The root-mean-squares (RMS) errors between the adjacent 8-year GNSS-R altimetry time series were 4.6 cm and 1.1 cm, for hourly and weekly sampling, respectively, indicated excellent agreement and a robust error estimate. When the GPS-derived sea level was compared with tide gauge sea level 13-km away, the results illustrated that the GPS-derived hourly sea level time series has a consistency of 8.0 cm RMS, while the weekly smoothed sea level time series increased the consistency accuracy to 1.5 cm RMS. To further the detection, the tidal harmonic analysis was performed for the two adjacent GPS sites and the tide gauge. The results showed the largest differences occurred by the underestimation of amplitudes of large tidal constituents in GPS-derived sea levels and the phase difference in smaller tidal constituents. As one of the most populated coastal regions of the world, the annual freezing and thawing of the Great Lakes and its influence on regional severe weather patterns significantly impact the local economy and ecosystems. Thus, accurate knowledge for the extent and thickness variations of lake ice in the Great Lakes, and their roles in the severity of winter storm and lake effect patterns are of importance to mitigate winter weathers for the people and the economies in the region. In this study, a novel method for lake ice thickness retrieval was proposed and developed, which was mainly based on a combination of a single geodetic quality GNSS receiver and a collocated water level lake gauge. For the first time, we estimated a 12-year lake ice thickness time series near the vicinity Harbor Beach on Lake Huron, and its reliability was validated by ice coverage product. The result initiates the opportunity for the potential use of this new measurement type of near shore lake ice thickness variations, in the assimilative modeling of Great Lakes Forecasting System, to improve the predictability of lake effects and severe winter storms.

Committee:

Che-Kwan Shum, Professor (Advisor)

Subjects:

Climate Change; Electrical Engineering; Hydrologic Sciences

Keywords:

GNSS-R, Sea Level, Lake Ice Thickness, Electromagnetic Bias, Tide, Signal-to-Noise Ratio

Klompmaker, Adiël A.Mesozoic Decapod Diversity with an Emphasis on the Early Cretaceous (Albian) of Spain
PHD, Kent State University, 2012, College of Arts and Sciences / Department of Geology
Decapod crustaceans are known to have lived in a variety of sedimentary environments in the geological past including reefs. This dissertation focuses on fossil decapods found mainly in reef environments, specifically coral reefs. For that purpose, the Early Cretaceous (late Albian) reefal carbonates from the Koskobilo quarry of the Albeniz Unit within the Eguino Formation in northern Spain were sampled for decapods during parts of the summers of 2008, 2009, and 2010. In total, 36 decapod species were found in this quarry based on 1100 specimens. Seventeen new species and eight new genera are described herein. The fauna from Koskobilo consists of brachyuran and anomuran decapods; shrimp and lobsters are absent. Based on an overview of decapod-rich localities and formations from the Cretaceous, the Koskobilo locality and the Eguino Formation appear to be the most diverse known thus far, both on the species and genus level. Other Cretaceous localities and formations associated with corals also show high decapod diversities, consistent with high decapod abundances in coral reefs from the Recent. The highest decapod diversity within the Koskobilo quarry is found in association with in situ branching corals. The specimens found at this site are statistically smaller than those from other decapod-rich localities in the quarry, which are not associated with these corals. Decapod diversity throughout the Mesozoic varies significantly with a peak diversity in the Late Jurassic on the species level. Based on the collection of ecological data from all ~1300 Mesozoic decapods, it appears that this peak is in part caused by the explosive radiation of brachyuran and anomuran decapod species in coral and, to a lesser extent, sponge reefs, coincident with a high eustatic sea level. The drop in diversity of anomuran and brachyuran species near the Jurassic/Cretaceous boundary was probably caused by the collapse of reefs due to a lowering of the eustatic sea level. More decapods have been found in the mid-Cretaceous and Late Cretaceous, possibly due to a radiation of Brachyura, coincident with a high eustatic sea level. To highlight the vast development of decapods during the Mesozoic the term 'Mesozoic Decapod Revolution' is proposed.

Committee:

Rodney Feldmann (Advisor); Carrie Schweitzer (Committee Member); Joseph Ortiz (Committee Member); Ferenc de Szalay (Committee Member)

Subjects:

Biology; Geology; Oceanography; Paleoecology; Paleontology; Zoology

Keywords:

Cretaceous; Decapoda; Meszoic; fossil; crab; Spain; diversity; biodiversity; Albian; systematics; paleontology; geology; reef; sea level; decapod; lobster; shrimp; coral; evolution; paleoecology; Mesozoic decapod revolution

Engelis, TheodossiosRadial orbit error reduction and sea surface topography determination using satellite altimetry /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites;Sea level;Altimeter

Huang, ZhenweiThe Role of Glacial Isostatic Adjustment (GIA) Process On the Determination of Present-Day Sea-Level Rise
Doctor of Philosophy, The Ohio State University, 2013, Geodetic Science and Surveying
Global sea-level rise has become one of the major social-economic hazards associated with the consequence of global warming. Geodetic sea-level change measurements, including tide gauge, radar altimetry and GRACE (Gravity Recovery And Climate Experiment), are contaminated by the ongoing glacial isostatic adjustment (GIA) process that is the viscoelastic response of the Earth to the loading of glaciation and deglaciation during a glacial cycle. Traditionally the GIA effect is removed from various geodetic sea-level observations by using a predicted correction from a GIA forward model. In this study, theoretical treatment of how the GIA effect should be specifically addressed for correcting various geodetic sea-level observations is described, and the results of an accuracy assessment study using an ensemble of 15 contemporary GIA models is conducted to estimate the effect of the current GIA model uncertainty on sea-level and ice-sheet mass balance studies. We find that large discrepancies exist in contemporary GIA models and some of the models are not internally consistent with regard to the two theoretically predicted relations. Using the elastic sea-level fingerprint method, recent change in Earth’s dynamic oblateness (or J2), 2003–2012, resulting from present-day ice sheet and mountain glacier/ice cap mass losses is studied. Sensitivity test and result shows that the contribution of mass loss from regions such as the glaciers systems in the Canadian Arctic Archipelago and Alaska are not negligible, although the dominant contributor remains the Antarctic and Greenland ice-sheets. Combining different sea-level change observations (satellite altimetry, GRACE and Argo), published contemporary studies have claimed the ocean mass component of sea-level budget “closure”, meaning that the two independent data types (de-steric satellite altimetry sea-level change and GRACE ocean bottom pressure change) agree with each other during 2004–2012. We argue that the sea-level budget is not closed, or it is a mis-closure depending on the choice of a particular GIA model to correct the GRACE data. The limitation is primarily due to the error in the current GIA models, followed by short or inadequate data span (less than 10 years), and errors in the observations. To mitigate the GIA model error, we develop a method to address the possibility to separate GIA signal and the present-day mass change over the ocean by combining GRACE and steric-corrected radar altimetry observations. For the first time, our result demonstrates a potential separate of the GIA and present-day mass change signals, and thus proving an improved present-day mass component of the sea-level rise. The estimated averaged ocean GIA crustal uplift ranges from –0.49 to –0.65 mm/yr, compared to –0.29±0.08 mm/yr that is averaged using an ensemble of 14 GIA models. The estimated present-day ocean mass change causing sea level to rise between 2.23 and 2.39 mm/yr, as opposed to the steric-corrected sea level change from radar altimetry observations at 1.52 mm/yr. The limitation is the short data span and errors in the observations, including hydrographic data did not adequately sample the full depth of the ocean or in time, errors in the altimeter and GRACE data.

Committee:

C.K. Shum (Advisor); Michael Bevis (Committee Member); Christopher Jekeli (Committee Member)

Subjects:

Climate Change; Earth; Geophysics

Keywords:

Glacial Isostatic Adjustment; Sea-Level Rise; GRACE; Radar Altimetry;

Cohoon, Nikkita DoloresWe Used Clothespins
Master of Fine Arts (MFA), Bowling Green State University, 2011, Creative Writing/Poetry

In We Used Clothespins, a correspondence is built amid echoes of the unsaid. Objects accumulate and amass; transmutation occurs and we shrug off what remains. The poems in this manuscript attempt to scrutinize the tangible, the scuffed surface, and dig holes in the center of worlds below sea level. Process acts as a filter for seeing—through crosshatched lines, the folds of a skirt, or the tenuous stretch of a spider web, both readers and speakers are able to navigate the fields created on the page, in the mind. The poems follow a trajectory of obsession that in the end transcends into an experience that is charged by something intangible but still felt.

Beginning in sections I and II, the reader is invited into an altered space that is just peripheral to our plane of existence, but entered into through a comfortable contract of interaction between the reader and the poems. Sections III and IV explore the potential for a voice to transfix and suspend disbelief; a voice that with its own power can reveal imagery and situations beyond the framework of the everyday.

Drawing upon art processes, words become like materials akin to oil paints, cut paper, or watercolors. The materials are built up in layers, and sometimes examined for their sheer physicality. These processes are enacted as a means toward an acute way of seeing. Throughout, language and syntax are used in a similar way one might build up marks in a drawing to move beyond traditional narrative into an extended moment or experience.

Committee:

Larissa Szporluk (Committee Chair); F. Daniel Rzicznek (Committee Member); Sharona Muir (Committee Member)

Subjects:

Fine Arts; Literature

Keywords:

poetry; process; arts; ekphrasis; sea level

Ranasinghage, Pradeep NalakaHolocene Coastal Development in Southeastern-Eastern Sri Lanka: Paleo-Depositional Environments and Paleo-coastal Hazards
PHD, Kent State University, 2010, College of Arts and Sciences / Department of Geology

Following the 2004 Asian tsunami, worldwide tsunami scientists recognized the need for identifying stratigraphic signatures of paleo-tsunami events in the Indian Ocean and to develop a regional tsunami chronology. This project carried out detailed, fine resolution, sediment profile studies to recognize the signatures of paleo-coastal environmental change in southeastern and eastern Sri Lanka, so that they can be differentiated from the regional record of tsunami deposits.

Sediment cores (~100 m total sediment) were extracted along landward transects from nine lagoons, two swales, and one back barrier marsh along the prograding coastline in southeastern and eastern Sri Lanka. Multiple proxies, including grain size, magnetic susceptibility (MS), visible and near IR reflectance, chemical composition, mineralogy and texture of sediments, micro, and macro fossil contents were used for this study. Measurements of grain size, MS, reflectance, and x-ray florescence were taken at 1-2 cm resolution. AMS 14C dating was used for age determination.

Results indicate a sea level high-stand between 5200-4900 yrs BP followed by sea level stabilization. Gradual filling of the Kirinda paleo-estuary and the Okanda lagoon commenced around 4900 yrs BP as a result of this sea level stabilization. Proxy evidence and a high rate of erosion after 4500 yrs BP suggests a sea level regression after 4500 yrs BP. Beach ridge development started around 4900 yrs BP and intensified after 2500 yrs BP.

Climate proxies suggest a weakened monsoon system until ~3500 yrs BP, when monsoon activity gradually increased. Four drought phases around 5500, 4500-3500, 1500 and 300 yrs BP are recognized. Significant ~6yr, ~20-25 yr and ~128 yr cycles, in monsoon variability can be discerned in wavelet power spectra of climatic proxies. According to previous studies, these Indian monsoon cycles are controlled by ENSO and solar variability.

According to results, the most recent pre-2004 tsunami event likely occurred around 1000 yrs BP with the older events around 4200 yrs BP and 4900 yrs BP. The sedimentary record from these estuaries, lagoons, and beach-ridge plains shows clear localized evidence for several additional flood and storm events, and possibly two other tsunami events around 4500 yrs BP and 7000 yrs BP.

Committee:

Joseph Ortiz, Dr. (Advisor); Alison Smith, Dr. (Committee Member); Elizabeth Griffith, Dr. (Committee Member); Andrew Moore, Dr (Committee Member)

Subjects:

Geology

Keywords:

Paleo-tTsunami; paleo-climate; sea level; Sri Lanka; Indian Ocean