While tropical cyclone (TC) track forecasting has improved noticeably over the last twenty years, intensity forecasting has remained somewhat of an enigma to forecasters. Despite increased computing capabilities and more sophisticated dynamical models, statistical models, such as the Statistical Hurricane Intensity Prediction Scheme (SHIPS), still often outperform their dynamical counterparts. There has been a great deal of research focused on improving intensity forecasts of TCs during the past two decades. However, the overwhelming majority of this statistical research has focused on the impacts of the storm environment rather than the effects of the TC structure itself or inner-core measurements. More focus has been placed recently on using some of these measurements from within the TC core, such as the structure of the storm and reconnaissance flight data. Still, much work remains to be done to fully utilize the available data from the inner core of TCs. To this end, flight data from Hurricane Hunter reconnaissance missions will be exploited to the fullest extent in this study. This research seeks to develop a new statistical-climatological forecasting scheme to improve short-term intensity forecasts for well-developed TCs in the Atlantic basin. Well-developed TCs are classified in this study as having a defined eye. Using Vortex Data Messages (VDMs) gathered from the aforementioned reconnaissance flights and stored in the National Hurricane Center's (NHC) Automated Tropical Cyclone Forecast (ATCF) archives, a VDM climatology from 1991-2008 is developed. These VDMs are collected from dropsondes and include various structural and thermodynamic parameters. This climatology includes storm-scale thermodynamic parameters to aid in TC prediction. A new climatological forecast tool is produced which gives the expected rate of intensity change for 12-48 hour periods based on an initial eye diameter and wind speed. This climatological tool also provides insight into the dynamics involved in hurricane intensity change. Other implications based on the climatological forecast tool, such as the ability to produce probabilistic intensity range forecasts, are also discussed. Finally, stepwise multiple linear regression is performed to create a SHIPS-style intensity forecast model (Atlantic-based Statistical Prediction of Hurricane Intensity using Recon, or ASPIRE). Examination of the regression equations and the change in predictors selected with varying intensity and forecast length offers additional insight into the science of TC intensity forecasting. Cross-validation results show that the ASPIRE technique outperforms SHIPS at nearly every forecast time and initial intensity, indicating that a new benchmark for TC intensity forecasting may have been attained. Two dependent case studies of Hurricane Ivan and Hurricane Katrina are presented for further analysis of the ASPIRE technique. Further work involving the utilization of satellite data to create proxy VDMs may lead to an expanded climatological database of inner-core data for TCs in the Atlantic basin as well as the capability to create similar regression schemes in the East Pacific and West Pacific basins. / A Thesis Submitted to the Department of Meteorology in Partial Fulfillment of the Requirements for the Degree of Master of Science. / Fall Semester, 2009. / November 6, 2009. / Tropical Cyclone Intensity Forecasting, Intensity Prediction, Aircraft Observations, Forecast Model, Eye Structure Forecast Tool, Statistics, Hurricanes, Regression Model / Includes bibliographical references. / Robert Hart, Professor Directing Thesis; Carol Anne Clayson, Committee Member; Philip Sura, Committee Member.

This study investigates data assimilation impacts of near-term satellite-derived nowcasted rainfall information (i.e., 3-hourly independently forecasted rainrates) in the initialization phase of a nonhydrostatic mesoscale model used for predicting severe convective rainfall events over the Korean peninsula. Infrared (IR) window measurements from the Japanese Geostationary Meteorological Satellite (GMS) are used to specify downstream rainrates during a spinup period of the model -- but in a future time framework since the independently acquired forecasted rainrates are used as assimilation control after the pre-forecast period has expired. This is tantamount to initializing in advance of real time in the context of operational forecasting. The main scientific objective of the study is to investigate the strengths and weaknesses of this data assimilation scheme insofar as its influence on quantitative precipitation forecasting (QPF) during the summertime Korean rainy season. Although there have been various recent improvements in formulating the dynamics, thermodynamics, and microphysics of mesoscale models, as well as computer advances which allow the use of high resolution cloud-resolving grids and explicit latent heating over regional domains, spinup remains at the forefront of unresolved mesoscale modeling problems. In general, non-realistic spinup limits the skill in predicting the spatial-temporal distribution of convection and precipitation, primarily in the early hours of a forecast, stemming from the inability of standard synoptic plus sub-synoptic observations to represent the initial diabatic heating field being produced by the ambient convection and cloudiness. The long-term goal of the research is to improve short-range (12-hour) QPF over the Korean peninsula through the use of innovative data assimilation methods based on geosynchronous (GEO) and/or low earth orbit (LEO) satellite precipitation information, either IR or preferably time lapse microwave (MW) measurements, once the latter are introduced by the forthcoming Global Precipitation Measurement (GPM) Mission. As a step in this direction, a new type of data assimilation experiment is performed in conjunction with high-frequency GMS-retrieved nowcasted rainfall information introduced to a mesoscale model. The 3-hourly "future time" precipitation forecast information is assimilated through nudging the associated moisture field (and thus the latent heating) during the early stages of a forecast period. This procedure enhances details in the moisture field during model integration, and thus improves spinup performance, as long as the error statistics of the future time precipitation estimates are superior to those intrinsic to background error statistics of the model. To incorporate the nowcasted rainrates, a nudging-based rainfall data initialization scheme using accumulated mean rainfall based on the future time rainrate information is applied during the first three hours of each 12-hour forecast period. To invoke this scheme more effectively, Newtonian relaxation is applied on the model's dynamic and thermodynamic variables during the preforecast period and before invoking the future time rainrate assimilation, which is a process referred as dynamic nudging. This procedure limits large–scale error growth and allows development of large-scale balance in the model's prognostic variables by guiding the relaxation toward the ambient large-scale analysis. The following numerical experiments are then performed: (1) control (CTL) – without any data assimilation, (2) rain assimilation (RAIN) – rainrate nudging only during the initial forecast period with three hours of nowcasted rainrates, and (3) rain assimilation with dynamic nudging (DYNRAIN) – nudging of winds and temperatures to the large-scale analysis for six hours during the preforecast period, and then nudging the model-forecasted rainrates with three hours of nowcasted rainrates. The integration cycle of the experiments consists of a 12-hour preforecast period prefacing a 12-hour forecast period, thus defining a complete 24-hour model integration period. The above methods are tested on three flood-producing storm cases that took place over South Korea during the summer seasons of 1998, 1999, and 2000. For purpose of validating the GMS precipitation nowcasts, one-minute sampled raingauge measurements are used. These data were acquired from the dense operational Automatic Weather Station (AWS) network (i.e., some 530 raingauges distributed over South Korea) maintained by the Korean Meteorological Administration (KMA). These experiments help shed light on how operational precipitation forecasts made during the Korean rainy season could possibly be improved by applying a GEO satellite-based (or possibly a ground-radar network-based) data assimilation scheme in which "future time" rainrate conditions would be represented at a prediction model's initialization time. It is found that assimilation of nowcasted rainrates alone during the early hours of a forecast period, produces better precipitation forecasts for low to medium rainrates, as well as better organized vertical velocity fields, than generated in the CTL experiments. Application of the dynamic nudging procedure during the preforecast period produces even better precipitation forecasts vis-à-vis rain location and intensity, especially for medium to heavy rainrates. Thus, combined use of dynamic nudging during the preforecast period and future time rain assimilation during the forecast period produces superior forecasts relative to CTL, RAIN only, or dynamic nudging only (i.e., DYNRAIN assimilation without follow-on RAIN assimilation). Forecast skill, quantified by threat and skill scores for heavy rainrates, are improved in the DYNRAIN experiments, although the bias scores for the DYNRAIN experiments are only slightly larger than for the RAIN experiments. The impact of the assimilation scheme depends to some degree on the characteristics of the precipitation events. The 2000 case study undergoes a greater combined impact of dynamic nudging during the preforecast period and rain assimilation during the forecast period, relative to associated impacts for the 1998 and 1999 case studies. Overall, the analysis suggests that the combined nudging procedure, as embodied in the DYNRAIN scheme, would lead to measurable improvements in mesoscale model-based QPF from convective storms over the Korean Peninsula. / A Dissertation Submitted to the Department of Meteorology in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy. / Fall Semester, 2003. / October 23, 2003. / Future Time Data Assimilation, Short-Range QPF, Nowcasting / Includes bibliographical references. / Eric A. Smith, Professor Co-Directing Dissertation; Henry E. Fuelberg, Professor Co-Directing Dissertation; James B. Elsner, Outside Committee Member; T. N. Krishnamurti, Committee Member; Xiaolei Zou, Committee Member.

Traditional surface and upper-air observations are often absent over the tropical oceans. This lack of routine in-situ measurement, outside of special field programs, has limited the observational study of tropical cyclogenesis. Remote sensing from satellites, however, can provide information in regions where surface-based observing networks are not present. This study utilizes infrared satellite imagery and QuikSCAT-derived near-surface vorticity from the 2005 hurricane season in the North Atlantic to examine the relationship between deep convection and low-level vorticity during tropical cyclogenesis. QuikSCAT-derived cyclonic relative vorticity is identified in association with developing easterly wave disturbances tracked using NHC products and 3-hourly infrared satellite imagery. Area-averaged vorticity near mesoscale regions of convection within the easterly wave envelope is then computed. In most of the 19 cases examined, the low-level vorticity followed the convective evolution, decreasing or remaining nearly constant during periods of inactive convection and increasing as convective activity increased. A composite of North Atlantic easterly wave disturbances was constructed to characterize the average evolution of near-surface vorticity during tropical cyclogenesis. 48 hours prior to genesis, the average tropical disturbance has a region of cyclonic relative vorticity about 125 km in diameter with peak magnitude of approximately 1x10-4 s-1. During its subsequent evolution, the vorticity of the composite disturbance increases as convection increases until a tropical cyclone forms. These results are considered in the context of prior and future numerical simulations of tropical cyclogenesis. / A Thesis Submitted to the Department of Meteorology in Partial Fulfillment of the Requirements for the Degree of Master of Science. / Spring Semester, 2007. / December 8, 2006. / Quikscat, Seawinds, Tropical Disturbance, Tropical Cyclogenesis, Vorticity / Includes bibliographical references. / Paul D. Reasor, Professor Directing Thesis; Mark A. Bourassa, Committee Member; Philip Cunningham, Committee Member.

In this study, a scale interactions and energetics formulation is utilized to examine the kinetic (KE) and available potential energy (APE) maintenance of the Madden Julian Oscillation (MJO). An analysis that computes the energy exchange among frequencies of atmospheric phenomena, with the MJO as the centerpiece, is the primary focus of this study. The rotational and divergent components of the wind have been examined here, as these components have been found to elicit significant information regarding the overall atmospheric circulation, globally, in the tropics and in both hemispheric middle-latitude regions. The interactions among frequencies can occur both in-scale (quasi-nonlinear quadratic) and between scales (nonlinear triad interactions). A third examined component of the energy equations is the APE to KE, baroclinic exchange over specified frequencies. This is also of the in-scale type of exchanges. An analysis of 22 years of global, full-atmosphere (ECMWF) Re-Analysis data is undertaken, where the energetics of the MJO are computed for the global, tropics and hemispheric middle-latitudes. Specified frequencies with the time period of 3-7 days (synoptic), 30-60 days (MJO), 180 days (Semi-Annual), 365 days (Annual), 3-7 years (El Nino) and decadal (10 years and beyond) were the primary indices of MJO maintenance used within this study. These energetics were computed for the 300 hPa and 850 hPa levels of the atmosphere, for the entire 22 years, the 30 hPa maximum amplitude region of the Quasi-Biennial Oscillation, and for selected time periods during the ENSO episode lasting from 1997 to early 2001. The salient findings of this research are that the MJO is maintained within the upper and lower troposphere primarily by the baroclinic conversion of APE to KE through in-scale exchanges. The MJO is secondarily perpetuated, by the nonlinear scale interactions occurring among a triad of scales, that act to contribute positively to the MJO time-scale. Finally, the time mean-time transient buildup of KE on the MJO time-scale ranks third in the overall maintenance of the MJO. In the context of the KE exchanges, the rotational components have been illustrated to dominate those of the divergent form, which agrees with previous research indicating that the rotational component of the wind accounts for nearly 95 percent of the total horizontal wind. For the APE exchanges, the converse to the KE exchanges has been found, where the divergent components of the transfers typically is the prominent component among it and the rotational component. This is explained to occur as the divergent component of the wind typically has a stronger meridional component than the rotational wind, thus an increase in the horizontal temperature advection that comprises the APE equations is larger for the divergent component. Results in this study indicate that at 30 hPa, the QBO does not transfer KE to the MJO time-scale via triad interactions. Among the ENSO energetics computations, the maintenance of the MJO within the tropics during the neutral phase is dominated by the high frequency rotational component, whereas in the El Nino phase, the weak MJOs are losing energy most prominently in the tropics through the semi-annual time-scale. This result indicates that the nonlinear interactions of a triad of scales can offer one scale as the primary contributor of the MJO maintenance, while in a weak MJO phase, another unique scale can be leading the removal of KE from the MJO. For the ENSO event, geographic distributions of the triad exchanges of KE and APE components displayed strong positive contributions in latitudes poleward of 10 degrees, largely due to the stronger wind-speeds in these regions advecting the vorticity (rotational) and divergence (divergent) at comparatively larger magnitudes. The geographic distributions of KE and APE also made clear the strong spatial variability occurring among all time-scales. / A Dissertation Submitted to the Department of Meteorology in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy. / Spring Semester, 2005. / March 18, 2005. / Madden Julian Energetics Low Frequency / Includes bibliographical references. / T. N. Krishnamurti, Professor Directing Dissertation; Ruby Krishamurti, Outside Committee Member; Carol Anne Clayson, Committee Member; Robert Hart, Committee Member; James J. O'Brien, Committee Member.

The hurricane boundary layer thickness as determined through the uniform constant BL depth model and varying prescribed BL depth model presented by Smith and Vogl (2008) is compared to the Troen and Mahrt (1986) method. Smith and Vogl presented the uniform constant BL depth approach from Emanual (1986) and a spatially varying prescribed BL depth based on inertial stability from the gradient wind. The Troen and Mahrt method of diagnosing the boundary layer thickness using the Richardson number is a basis for the Hong and Pan or MRF boundary layer schemes available in many hurricane models including WRF and MM5. .Hurricane Isabel (2003) is analyzed from dropwindsondes and GFDL model output. An additional hurricane, developed in the CM1 without a specified boundary layer formulation, is analyzed for comparing methods in determining the boundary layer thickness. The in situ observations did not lead to any conclusive results, however the modeled environments did show patterns in the boundary layer depth which support a spatially varying depth. The inertial stability method and the Troen and Mahrt method of determining the boundary layer thickness differed with depths increasing with increasing radius away from the radius of maximum wind for the inertial stability method and depths decreasing with increasing radius away from the radius of maximum wind with the Troen and Mahrt method. / A Thesis Submitted to the Department of Meteorology in Partial Fulfillment of the Requirements for the Degree of Master of Science. / Fall Semester, 2009. / October 30, 2009. / Richardson Number, Isabel, CM1, GFDL, Boundary Layer, Hurricane / Includes bibliographical references. / Paul Ruscher, Professor Directing Thesis; T. N. Krishnamurti, Committee Member; Carol Anne Clayson, Committee Member.

As understanding of tropical cyclone (TC) evolution both during and beyond the tropical phase improves, forecasting and analysis techniques are adjusted accordingly. While these changes hopefully lead to more accurate forecasts, they introduce inconsistencies into best track datasets. The tropical cyclone reanalysis project was started in an attempt to remove such inconsistencies and biases (Landsea et al. 2004). It is important to understand biases within best track datasets before studies of long term trends can be meaningfully completed. Here, the strengths and limitations of the ECMWF reanalysis data (ERA40; Uppala 2005) are examined within the cyclone phase space (CPS; Hart 2003). This process included using the CPS to quantify biases and evolving trends in North Atlantic TC representation within the ERA40. It is found that TCs are poorly resolved even beyond what is expected given the ERA40's grid size. By binning data into three temporal groups it is found that the introduction of satellite data results in a drastic improvement in the representation of ERA40 TCs. Not surprisingly, TC size seems to have the most profound effect since the ERA40 grid size is 1.125° (Uppala 2005). It is also found that location (specifically longitude) also has a marked effect on TC representation within the ERA40, but it should be noted that location is linked to data density. Despite these inconsistencies, the ERA40 CPS can be used to scrutinize historical structural classification of some TCs, provided that the TCs are represented much better than the mean (usually by more than one standard deviation). Within this study, it is found that some TCs may require refined timing of extratropical transition. Others may need refined structural classification at the beginning or in the middle of their HURDAT tracks. Finally, there are some for which the ERA40 and HURDAT classifications agree throughout the duration of the TC's lifecycle. Within the study, cases from each of these subsets of TCs are presented and three potential additions to the best track dataset are examined. It should be noted that no potential revisions are suggested only when evidence outside of the ERA40 CPS can be obtained since no singular source should be the basis of revisions to the best track dataset. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester, 2007. / July 5, 2007. / Tropical Cyclone Structure, Climatology / Includes bibliographical references. / Robert Hart, Professor Directing Thesis; Paul Ruscher, Committee Member; Paul Reasor, Committee Member.

The tropical cyclone superensemble has provided skillful forecasts for Atlantic tropical cyclone activity for several years. Until very recently, the tropical cyclone superensemble had only been run using a suite of large scale models. Using large scale models within the Florida State Superensemble produced noticeable improvement over each of the respective member models with respect to track and intensity forecasting. The more recent development of operational tropical cyclone mesoscale models led to the development of the mesoscale tropical cyclone Florida State Superensemble, which is utilized for this study. This study uses a combination of four different mesoscale models. One model is currently being run operationally for the National Hurricane Center and the other three models are in-house models run at Florida State University. This research includes most of the tropical cyclones that occurred during the 2004, 2005, and 2006 Atlantic hurricane seasons. There are twenty six storms available for study during that period and most storms have a 0000 UTC and 1200 UTC initialization. This provides the Florida State Superensemble with fifty-seven forecast cases. For each storm the Florida State Superensemble issues track, minimum sea level pressure, and maximum wind forecasts out to seventy-two hours at six hourly intervals. These tracks and intensities are compared to the "best track" analysis as determined by the National Hurricane Center. The results show that the tropical cyclone Florida State Superensemble can provide accurate forecasts when using a suite of mesoscale models, though increased work needs to go into improving the accuracy of the member models, which on average have slightly higher errors than the similarly run Florida State Superensemble with large scale member models. This study quantifies the errors of the Florida State Superensemble, ensemble mean, and the respective mesoscale models, compares them to the large scale models, and examines several ways that the mesoscale tropical cyclone Florida State Superensemble can be enhanced for future work. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester, 2008. / May 23, 2008. / Tropical Cyclone Forecasting, Model Verification, Tropical Cyclone Intensity, Tropical Cyclone Track, Tropical Cyclone Model Limitations / Includes bibliographical references. / T. N. Krishnamurti, Professor Directing Thesis; Robert Hart, Committee Member; Paul Ruscher, Committee Member.

Two emerging datasets, QuikSCAT surface winds and Global Positioning System (GPS) radio occultation (RO) vertical soundings, have the potential to improve tropical cyclone (TC) initialization and, in turn, improve TC prediction. QuikSCAT surface wind with high horizontal resolution and GPS RO temperature and moisture profiles with high vertical resolution can observe TC environments where conventional observations are lacking or non-existent, substantially enhancing the current observation network. These data may be beneficial in the initialization of structures of weak TCs into NWP models, which currently is a major challenge of the present bogus data assimilation (BDA) schemes. This work explores the potential utility of these data in TC observations by selecting a large number of cases for the North Atlantic (NATL) basin for the 1999-2004 hurricane seasons for QuikSCAT and 2001-2003 hurricane seasons for GPS RO. Data coverage, close proximity to the TC center, and observations within +/-3 h of comparison data times were criteria for case selections. QuikSCAT-derived parameters important in BDA (i.e., maximum wind, radius of maximum wind, and the 34-kt radius) were compared with those from the National Hurricane Center (NHC) and the Hurricane Research Division (HRD). GPS RO vertical soundings of bending angle and refractivity were compared with soundings derived from the National Centers for Environmental Prediction (NCEP) dataset and dropsondes. Results from this study show that both datasets have great promise for improving TC initialization and prediction. These comparisons revealed some quality issues in the data that are exasperated in TC environments because of high incidence of rainfall (QuikSCAT) and high ambient water vapor content in the lower troposphere (GPS RO). These data quality concerns need to be addressed before assimilation of these data can be undertaken. Noticeable errors and biases in these observations are found to be weather-dependent. In future work, adjoint sensitivity and four-dimensional variational (4D-Var) minimization studies will be used to assess the impact these datasets will have in hurricane prediction. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester, 2005. / July 8, 2005. / Refractivity, NHC Parameters / Includes bibliographical references. / Xiaolei Zou, Professor Directing Thesis; Robert Hart, Committee Member; Mark Bourassa, Committee Member.

El Nino-Southern Oscillation (ENSO) is a widely known phenomenon that affects many areas including the southeast United States. Over the southeast U.S. the Japan Meteorological Agency (JMA) ENSO index was modified to establish better classifications. In order to properly understand the effects of ENSO on this location a new approach was needed. Spatial resolution was improved by utilization of the PRISM dataset. PRISM provided monthly precipitation and temperature data over the contiguous US at 4 km resolution. Temporal resolution was improved by disregarding the traditional JMA definition of an ENSO year. The new definition requires six consecutive months of 0.5°C anomalies or larger to be listed as an ENSO event. By utilization of this definition, the ENSO index was modified to a monthly index from a yearly index. Many ENSO events begin in the summer months and end before the preceding September, therefore, an adoption of a monthly index is justified. Although several of the effects vary widely over the domain, there are a few prevalent patterns of ENSO effects. During warm phase, from November-April, wet conditions are seen in the coastal areas. July and August are both dry. From fall to spring, Florida and the Atlantic Coast are basically dry, however; the Mississippi River Valley doesn't appear wet as previous studies have indicted. Patterns of temperatures across the southeast are less variable than the precipitation. Differences between the ModJMA and JMA can be seen in several months, especially during late spring and early autumn. This result is not surprising based on the rigid definition of the JMA index. An interesting result presented itself throughout the study. Individual tropical storms can be identified with the increased resolution PRISM data provides. A state by state breakdown of the ModJMA conclusions provides regional summaries. The ModJMA better classifies ENSO periods and leads to a more precise impact of ENSO over the southeast United States. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2009. / October 30, 2008. / HCN, Southeastern US, JMA, PRISM, ENSO, COOP, Regional Scale, Tropical Activity, Spring, Summer, ENSO Period, ModJMA / Includes bibliographical references. / James J. O’Brien, Professor Directing Thesis; Philip Cunningham, Committee Member; Ming Cai, Committee Member.

One of the goals of NASA's Intercontinental Chemical Transport Experiment Phase B (INTEX-B) was to perform quasi-Lagrangian (q-L) sampling of air pollution as it is transported across the Pacific Ocean from Asia toward North America. We define q-L as air pollution sampled by one aircraft that is later sampled at another location. Iterative procedures are required to determine q-L segments along aircraft flight paths during the INTEX-B sampling. We set meteorological criteria and ran backward trajectories from the C-130 aircraft to determine if q-L connections were made with the DC-8 flights. National Centers for Environmental Prediction (NCEP) reanalyses and GOES satellite imagery help provide a meteorological overview for each case and verify air flow calculations from the trajectory model. In-situ chemical data are used to adjust and confirm the q-L segments. Four case studies are examined. Backward trajectories from the DC-8 q-L segments show that the polluted air masses mostly have Asian origins. Between aircraft sampling, chemical aging rates calculated from a photochemical model show some differences between in-situ-derived aging and model-derived aging. These differences can be attributed to factors such as mixing, dilution, and surface deposition. Carbon Monoxide (CO) from the Atmospheric InfraRed Sounder (AIRS) and from the Goddard Earth Observatory System (GEOS) chemical model shows the spatial extent and locations of the plume features being sampled. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2009. / March 5, 2009. / Quasi Lagrangian, Air Pollution / Includes bibliographical references. / Henry E. Fuelberg, Professor Directing Thesis; Robert Hart, Committee Member; Paul Ruscher, Committee Member.