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Title: Separation and Characterization of Copper Binding Ligands in Dissolved Organic Matter in Lake Bradford.
Creator: Prugue, Rodrigo, Earth, Ocean & Atmospheric Science
Abstract/Description: Trace metals are important compounds in aquatic environments. In low concentrations, they can be very beneficial to aquatic life. However, they can be toxic if present in moderate to high concentrations. A growing interest has occurred involving ligands. Trace metals like copper are most commonly found complexed with ligands in fresh and marine waters. Many organisms also produce compounds to help mitigate increases in dissolved copper and prevent toxic environments. However, very little is...
Show moreTrace metals are important compounds in aquatic environments. In low concentrations, they can be very beneficial to aquatic life. However, they can be toxic if present in moderate to high concentrations. A growing interest has occurred involving ligands. Trace metals like copper are most commonly found complexed with ligands in fresh and marine waters. Many organisms also produce compounds to help mitigate increases in dissolved copper and prevent toxic environments. However, very little is known on how these ligands behave and what causes them to complex with trace metals. This project aims to separate and characterize copper binding ligands from a local lake in Tallahassee, FL. The motivation is to improve understanding of this complex process and mitigate future environmental issues dealing with elevated issues of metals in aquatic environments. UV/Vis spectrometry data did not yield any conclusive results since the peaks seen were very similar to what copper and the chelating agent used, EDTA, looked like. However, the data produced by the electrospray ionization mass spectrometer does indicate the presence of specific compounds which were affected by the pH of the solution. Although the data did not yield any characteristic data, we concluded that the IMAC process is capable of fractionating copper binding ligands.
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Date Issued: 2012
Identifier: FSU_migr_uhm-0064
Format: Thesis

Title: Remotely Sensed Validation of Numerical Weather Prediction Estimates of Wind Speed Near Tropical Cyclones.
Creator: Dacey, Connor, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: This study examined the tendencies of the European Center for Medium-Range Weather Forecasting Ensemble Prediction System (ECMWF-EPS) control forecast of wind speeds near two rapidly intensifying tropical cyclones (TCs) in the Indian Ocean. The ECMWF-EPS control forecasts were compared with the Advanced Scatterometer (ASCAT) wind speed measurements, which were considered comparison and "truth" data for this study. In total, 6 days of model forecast and ASCAT data were collected and analyzed...
Show moreThis study examined the tendencies of the European Center for Medium-Range Weather Forecasting Ensemble Prediction System (ECMWF-EPS) control forecast of wind speeds near two rapidly intensifying tropical cyclones (TCs) in the Indian Ocean. The ECMWF-EPS control forecasts were compared with the Advanced Scatterometer (ASCAT) wind speed measurements, which were considered comparison and "truth" data for this study. In total, 6 days of model forecast and ASCAT data were collected and analyzed for severe tropical cyclones Phet and Giri. Differences in the magnitudes of the wind speeds near the TCs were calculated. From these, areas can be seen in which the ECMWF-EPS control over-forecasted and under-forecasted the wind speeds. These results also help explain how the model tendencies changed throughout the lifespan of the TCs. Overall, wind speed errors were greatly associated with errors in storm location, storm shape, and storm size. No exact conclusion about the tendencies of the ECMWF-EPS control forecasts could be made due to a lack of patterns or clear biases associated with the wind speed difference results. A more in-depth study must be completed to further comment on specific tendencies of the model. Nevertheless, this study could begin the investigation into how to improve wind speed forecasts for TCs in the Indian Ocean in an effort to better save life and property in the future.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0548
Format: Thesis

Title: Multi-Decadal Variations of Durations of Extreme Temperatures in the Southeastern United States.
Creator: Worsnop, Rochelle, Earth, Ocean & Atmospheric Science
Abstract/Description: The number of extreme temperature occurrences and their durations in the southeast United States varies during three periods: the Warm Regime subset (WRs), the Cold Regime subset (CRs), and the Modern Record (MR). Multidecadal variations in the regional patterns of the counts and durations of summer-day and winter-day extremes reveal that during the MR, the extreme temperature counts and durations in Florida are more consistent with a WRs setup whereas these parameters for the inland states ...
Show moreThe number of extreme temperature occurrences and their durations in the southeast United States varies during three periods: the Warm Regime subset (WRs), the Cold Regime subset (CRs), and the Modern Record (MR). Multidecadal variations in the regional patterns of the counts and durations of summer-day and winter-day extremes reveal that during the MR, the extreme temperature counts and durations in Florida are more consistent with a WRs setup whereas these parameters for the inland states (Alabama, Georgia, North Carolina, and South Carolina) are more consistent with a CRs setup. We also found that during the CRs (WRs), the majority of stations show a statistically significant increase in the likelihood of exactly one winter-day (summer-day) extreme occurrence. During the MR, both inland and coastal stations show a statistically significant increase in the likelihood of exactly one winter-day occurrence. This increased likelihood is not seen during the MR for a summer-day extreme occurrence. Patterns in the behavior of summer-day and winter-day extremes during the CRs and WRs may provide insight about how extreme temperatures will behave in future periods, if the period is forecasted to have similar setups to that of the CRs or WRs. Insight about the duration and counts of extreme temperatures is useful to the agricultural community, power industries, and health officials.
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Date Issued: 2012
Identifier: FSU_migr_uhm-0050
Format: Thesis

Title: Investigating Relationships Between Rising Temperatures and Heavy Rainfall Events in the Southeastern U.S. Using Analog Methods.
Creator: Zuromski, Lauren, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: This study examines how extreme precipitation influences temperatures, and how temperature extremes influence precipitation in the Southeastern U.S., seasonally, using observational data. For the precipitation influencing temperature approach, three precipitation regimes are created (wet, dry, and neutral) to observe possible shifts in the distributions of seasonal average daily maximum and minimum temperatures based on precipitation extremes. Similarly, for the temperature influencing...
Show moreThis study examines how extreme precipitation influences temperatures, and how temperature extremes influence precipitation in the Southeastern U.S., seasonally, using observational data. For the precipitation influencing temperature approach, three precipitation regimes are created (wet, dry, and neutral) to observe possible shifts in the distributions of seasonal average daily maximum and minimum temperatures based on precipitation extremes. Similarly, for the temperature influencing precipitation, three temperature regimes are created (warm, cool, and neutral), to observe how the frequency of rainfall events of 1.00" or more shifts in each temperature regime. For the precipitation influencing temperature approach, most notably, it is found that in summer, spring, and fall, in a wet precipitation regime, the maximum temperatures are typically warmer (cooler) than the average maximum temperatures in a neutral regime; the opposite pattern is observed for winter. It is also found that these temperature distributions do not shift in a uniform way across the Southeast, though several regional continuities exist. For the temperature influencing precipitation approach, it is found that spring, summer, and winter show the largest differences in the frequency of rainfall events of 1.00" or more between the cool and warm temperature regimes. This study also examines five case study stations in the Southeast to observe regional nuances in temperature and precipitation patterns.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0511
Format: Thesis

Title: The Influence of Atmospheric Cold Air Outbreaks on the Upper Ocean Thermal Variability of the Florida Straits.
Creator: Rudzin, Johna, Earth, Ocean & Atmospheric Science
Abstract/Description: The purpose of this study is to investigate the impacts of cold air outbreaks (CAOs) on the sea surface temperature (SST) in the Florida Straits (FS) during different configurations (mature or immature) of the Loop Current (LC). A satellite-derived SST data set is used to calculate the difference in SST anomalies between the FS and the Yucatan Channel (YC). The SST anomaly time series is analyzed during the winter season for times of mature and immature LC configurations determined from a...
Show moreThe purpose of this study is to investigate the impacts of cold air outbreaks (CAOs) on the sea surface temperature (SST) in the Florida Straits (FS) during different configurations (mature or immature) of the Loop Current (LC). A satellite-derived SST data set is used to calculate the difference in SST anomalies between the FS and the Yucatan Channel (YC). The SST anomaly time series is analyzed during the winter season for times of mature and immature LC configurations determined from a satellite altimetry-derived time series of LC position. This analysis shows a greater likelihood of anomalous cooling of SSTs in the FS compared to the SSTs in the YC during times of an extended, or mature, LC. This result leads to the hypothesis that surface water is subject to greater cooling during a mature LC (due to the greater residence time of the water under cold air masses) than an immature LC, and this cooler water is advected into the FS. This hypothesis is investigated by computing an approximate heat budget for the Yucatan-Loop-Florida Current (YLFC) under identical atmospheric forcing using twin ocean model simulations with mature and immature LC configurations.
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Date Issued: 2012
Identifier: FSU_migr_uhm-0056
Format: Thesis

Title: The Increasing Intensity and Frequency of ENSO and its Impacts to the Southeast U.S.
Creator: McNaught, Carlysle, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: The El Niño Southern Oscillation (ENSO) is an important natural climate variation that affects large portions of the world. The changing magnitude and frequency of ENSO reveals that it is getting stronger as measured by the maximum anomaly in sea surface temperature (SST). Principal component analysis of the ENSO is conducted to estimate the spectrum of the SST of the time series. The intensity of the ENSO events during the period 1970—2010 is statistically significantly higher when compared...
Show moreThe El Niño Southern Oscillation (ENSO) is an important natural climate variation that affects large portions of the world. The changing magnitude and frequency of ENSO reveals that it is getting stronger as measured by the maximum anomaly in sea surface temperature (SST). Principal component analysis of the ENSO is conducted to estimate the spectrum of the SST of the time series. The intensity of the ENSO events during the period 1970—2010 is statistically significantly higher when compared to the period 1930—1970, with a broad spectral peak centered around 4 years. When we compare the SST spectrum for the period 1930—1970 with the spectrum for 1970—2010, we find the latter period to be much stronger in power. The resultant impact of more powerful and frequent ENSO events on the Southeast United States is examined through a spatial and temporal statistical analysis of precipitation and temperatures between the two time periods. Our analysis reveals statistically significant changes in precipitation during El Niño where the rainfall is much more widespread across the Southeast during the 1970—2010 period than the 1930—1970 period. The La Niña rainfall deficit is mainly confined to Florida in the latter period than the former. Finally, the temperature distribution, through an analysis of the first four statistical moments, showed conventional responses to the changes in ENSO precipitation such as an anomalous decrease in maximum temperatures during El Niño and an overall anomalous increase in temperatures during La Niña.
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Date Issued: 2014
Identifier: FSU_migr_uhm-0356
Format: Thesis

Title: IC to CG Lightning Relationships over the Tallahassee CWA.
Creator: Jackson, Karly M., Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: The formation of and the relationship between intra-cloud (IC) and cloud-to-ground (CG) lightning flashes have not been thoroughly studied. Understanding how these flash types interact in different types of thunderstorms can lead to a better understanding of lightning characteristics and how these characteristics can be applied to operational forecasting practices. Results of this study show that the IC:CG ratio varies greatly each day throughout the summer season over the County Warning Area...
Show moreThe formation of and the relationship between intra-cloud (IC) and cloud-to-ground (CG) lightning flashes have not been thoroughly studied. Understanding how these flash types interact in different types of thunderstorms can lead to a better understanding of lightning characteristics and how these characteristics can be applied to operational forecasting practices. Results of this study show that the IC:CG ratio varies greatly each day throughout the summer season over the County Warning Area (CWA) of the Tallahassee National Weather Service Forecast Office. The summer season is dominated by daily thunderstorms that form due to sea breeze fronts and their resulting outflow boundaries. Eleven case study storms reveal how IC and CG flash counts and rates in non-severe thunderstorms differ from those of severe storms such as those examined by Williams et al. (1999). Results of the present study reveal that the timing of CG lightning and the frequency of its strikes differ from those of severe storms. This is most likely due to severe storms producing stronger updrafts for longer periods of time than those of non-severe storms. The IC:CG ratios varied greatly among these case studies indicating that further studies must be done to determine a statistically significant understanding of how flash rates change and how the relationship between IC and CG flashes relate to the ratios they produce.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0552
Format: Thesis

Title: Hurricane Sandy and New Jersey: The Nature of a Natural Disaster.
Creator: Blaskiewicz, Claire S., Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: While natural disasters can often be catalysts for change, understanding where to begin changing can be discovered by looking at the science and history of the affected area. Hurricane Sandy's unprecedented landfall in October 2012 began this progression for the state of New Jersey. This study examines the processes affecting the ocean and beaches of New Jersey, looks at the effects of Hurricane Sandy on the state and discusses the changing standards that have been and continue to be enacted...
Show moreWhile natural disasters can often be catalysts for change, understanding where to begin changing can be discovered by looking at the science and history of the affected area. Hurricane Sandy's unprecedented landfall in October 2012 began this progression for the state of New Jersey. This study examines the processes affecting the ocean and beaches of New Jersey, looks at the effects of Hurricane Sandy on the state and discusses the changing standards that have been and continue to be enacted since storm recovery began. Specifically highlighted are the engineering practices of flood mitigation, the effects of the storm on the state's economy and the new policies and standards that have come about in the aftermath.
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Date Issued: 2014
Identifier: FSU_migr_uhm-0564
Format: Thesis

Title: A High Resolution Atmospheric Chemistry Simulation of Hurricane Sandy (2012).
Creator: Freeman, Sean, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: Hurricane Sandy (2012) had one of the greatest economic impacts of any hurricane in United States history. However, its broader scientific impacts, especially its impacts on the chemistry of the upper troposphere and lower stratosphere, have not been documented. This study uses the Weather Research and Forecasting with Chemistry model (WRF-Chem), run at a convective-permitting resolution, to examine the transport of pollutants inside Hurricane Sandy as it made landfall along the Eastern...
Show moreHurricane Sandy (2012) had one of the greatest economic impacts of any hurricane in United States history. However, its broader scientific impacts, especially its impacts on the chemistry of the upper troposphere and lower stratosphere, have not been documented. This study uses the Weather Research and Forecasting with Chemistry model (WRF-Chem), run at a convective-permitting resolution, to examine the transport of pollutants inside Hurricane Sandy as it made landfall along the Eastern Seaboard. Although several pollutants were examined, the concentrations of CO throughout the atmosphere and the transport of CO from sources along the coast in Hurricane Sandy's convective region were primary focus. A forward-trajectory analysis also was performed using the high-resolution WRF-Chem data as input to the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT). The results of this high-resolution chemical and meteorological simulation will be presented with a focus on transport to the upper troposphere and lower stratosphere. To our knowledge, such high-resolution chemical and meteorological simulations of tropical cyclones have not been reported in the previous literature.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0477
Format: Thesis

Title: Examining Shifts in Warm-Season Near-Surface Moisture Trends in Florida.
Creator: Swearingen, Aaron D., Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: Warm-season (1 June–31 August) near-surface moisture trends have been examined across Florida. Data was used from 86 National Weather Service cooperative stations, 24 NWS first-order stations, and the European Centre for Medium-Range Weather Forecasts' ERA-Interim satellite reanalysis. Seventy-five out of eighty-six NWS cooperative stations depicted high counts of maximum low temperature records being set or broken since 1990. Twenty-four NWS hourly stations were used in conjunction with the...
Show moreWarm-season (1 June–31 August) near-surface moisture trends have been examined across Florida. Data was used from 86 National Weather Service cooperative stations, 24 NWS first-order stations, and the European Centre for Medium-Range Weather Forecasts' ERA-Interim satellite reanalysis. Seventy-five out of eighty-six NWS cooperative stations depicted high counts of maximum low temperature records being set or broken since 1990. Twenty-four NWS hourly stations were used in conjunction with the Pettitt test to calculate a change point of 1990 over a 40-year period (1973–2012). Using the Pettitt results, a significant amount of NWS first-order stations depicted a rise in both early morning temperatures and dew points (Td) since 1990. A rise in total column water vapor (TCWV) was detected through the ERA-Interim reanalysis, indicating a possible increase in mid-level moisture in addition to that near the surface. A reversal in 850 hPa wind patterns and a potential shift in the Azores High were present in the reanalysis as well. An increase in atmospheric moisture levels is present and may be driven by synoptic-scale changes in wind patterns due to a shift in the Azores High.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0528
Format: Thesis

Title: An Examination of the Differences in Tropical Cyclone Pressure-Wind Relationships Among Observations, Model Analyses, and Model Forecasts.
Creator: Visin, Lauren, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: Despite significant advances in tropical cyclone (TC) track forecasting over the past few decades, intensity forecasts remain problematic, even for high-resolution computer models uniquely developed and tailored to TC prediction. This study examines the ability of two of these models, the Geophysical Fluid Dynamics Laboratory (GFDL) model and the Hurricane Weather Research and Forecasting (HWRF) model, to analyze and predict one measure of TC structure in the Atlantic Basin. Instead of more...
Show moreDespite significant advances in tropical cyclone (TC) track forecasting over the past few decades, intensity forecasts remain problematic, even for high-resolution computer models uniquely developed and tailored to TC prediction. This study examines the ability of two of these models, the Geophysical Fluid Dynamics Laboratory (GFDL) model and the Hurricane Weather Research and Forecasting (HWRF) model, to analyze and predict one measure of TC structure in the Atlantic Basin. Instead of more conventional evaluations based solely on a TC's maximum wind speed or minimum sea level pressure (MSLP), the relationship between these two variables is used: a TC's pressure-wind relationship (PWR), which gives a more detailed look at how well each model analyzes and forecasts TC structure. The analysis begins in 2007, the year the GFDL was initially "frozen" (development and improvements were ceased) and also the first year that the HWRF was used for operational forecasting. Comparison of both GFDL and HWRF analyses and forecasts to the National Hurricane Center's (NHC) "best track" (database of 6-hourly observations of vital statistics such as maximum wind speed and MSLP for all TCs) revealed that, while both models produced errors in their analyses and forecasts, the GFDL outperformed the HWRF in both analysis and forecasting of TC PWR's for Atlantic Basin hurricanes from 2007-2013.. There was a subsection of particularly strong TCs (maximum winds above 120kt, MSLP lower than 950mb) whose structure was forecast especially poorly. The forecast PWR's produced by the HWRF fell largely outside the "best track" for this set of intense TCs, suggesting that the structures produced by the HWRF are inconsistent with our best estimates of observations in the Atlantic Basin and given current climate conditions. The PWR distribution evolved considerably for the HWRF over time, presumably as model improvements were made (including a decrease in model gridspacing). This has led to the model analysis PWR becoming more consistent with the model forecast PWR envelope. Nonetheless, both often fall outside the best-track estimates of PWR and potential explanations for this disparity are presented.
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Date Issued: 2014
Identifier: FSU_migr_uhm-0386
Format: Thesis

Title: Determinig the Effects of Stokes Drift on the Movement of Oil in the Gulf of Mexico.
Creator: Heath, Nicolas, Earth, Ocean & Atmospheric Science
Abstract/Description: The impact of Stokes drift, a wave-driven mechanism of mass transport, is investigated for surface oil movement in the Gulf of Mexico. Stokes drift was neglected in trajectory forecasts in the Gulf during the Deepwater Horizon oil spill. The key considerations used in Gulf of Mexico trajectory forecasts were surface currents and wind drift. This study presents a physical argument for the importance of Stokes drift and questions the significance of wind drift over an oil slick. Furthermore,...
Show moreThe impact of Stokes drift, a wave-driven mechanism of mass transport, is investigated for surface oil movement in the Gulf of Mexico. Stokes drift was neglected in trajectory forecasts in the Gulf during the Deepwater Horizon oil spill. The key considerations used in Gulf of Mexico trajectory forecasts were surface currents and wind drift. This study presents a physical argument for the importance of Stokes drift and questions the significance of wind drift over an oil slick. Furthermore, the magnitude and direction of the wind drift (2–5% of the wind speed and 20° to the right in the Northern Hemisphere) is very similar to that of the Stokes drift. For this reason, the differences between Stokes drift and the wind drift are examined using a vector comparison. The directional components of Stokes drift and the wind drift are found to be very similar although the magnitudes of the wind drift are found to be larger. When swell not associated with the local wind is present, however, the two drifts have significantly different directional components. Horizontal surface trajectories are computed for different atmospheric and oceanic conditions. Trajectory results are compared to satellite-derived oil locations using a center of mass comparison method. Analysis of trajectory forecasts and observed oil locations suggests that Stokes drift might play an important role in the movement of oil at the surface and that the magnitude of the wind drift may not be as large as most models presume. Key
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Date Issued: 2011
Identifier: FSU_migr_uhm-0017
Format: Thesis

Title: Characteristics of WTLN-Derived Lightning.
Creator: Saunders, Matthew, Earth, Ocean & Atmospheric Science
Abstract/Description: Many studies have used cloud-to-ground (CG), intracloud (IC), and total (CG + IC) lightning to investigate relationships between lightning and severe weather. Although the National Lightning Detection Network (NLDN) is the most common system used to detect lightning, it is limited to reporting only CG lightning over the continental United States. The WeatherBug Total Lightning Network (WTLN) is a global data set recently established by Earth Networks, Inc. that reports both CG and IC...
Show moreMany studies have used cloud-to-ground (CG), intracloud (IC), and total (CG + IC) lightning to investigate relationships between lightning and severe weather. Although the National Lightning Detection Network (NLDN) is the most common system used to detect lightning, it is limited to reporting only CG lightning over the continental United States. The WeatherBug Total Lightning Network (WTLN) is a global data set recently established by Earth Networks, Inc. that reports both CG and IC lightning. WTLN has the potential to offer superior lightning data, although little research has compared WTLN information to other data sets like the NLDN. Using WTLN and NLDN data, distributions of stroke counts by polarity and peak current were plotted during a16-month study period near Cape Canaveral, FL. The WTLN data set showed an over detection of weak peak current strokes and under detection of strong peak current strokes. The WTLN data also exhibited higher overall stroke counts compared to NLDN. A case study of the Tuscaloosa-Birmingham tornado showed an opposite relation between WTLN and NLDN stroke counts. Compared to NLDN, the WTLN continually undercounted strokes during the lifecycle of the storm. While the number of counts was dissimilar, the two data sets correlated strongly (0.79) during the storm period. When the lightning was divided by polarity, WTLN showed a much greater detection of positive CG lightning than NLDN.
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Date Issued: 2012
Identifier: FSU_migr_uhm-0055
Format: Thesis

Title: A Case Study of a Hybrid Cyclone: 6-9 September 2009.
Creator: Sliwinski, Timothy, Earth, Ocean & Atmospheric Science
Abstract/Description: Hybrid cyclones, such as subtropical storms and warm seclusions, are generally defined by the fact that they contain characteristics of the main types of cyclones: tropical and extratropical. This case study examines whether a cyclone can be considered hybrid without experiencing a transition from either of these two main types. The case in question occurred between 6 and 9 September 2009 before becoming frontal. The cyclone formed independently of other cyclones and was shallow warm-core at...
Show moreHybrid cyclones, such as subtropical storms and warm seclusions, are generally defined by the fact that they contain characteristics of the main types of cyclones: tropical and extratropical. This case study examines whether a cyclone can be considered hybrid without experiencing a transition from either of these two main types. The case in question occurred between 6 and 9 September 2009 before becoming frontal. The cyclone formed independently of other cyclones and was shallow warm-core at its start. It would go on to exhibit properties of tropical cyclones such as a stacked surface warm-core and even convection occurring at the center. It would also go on to exhibit properties of extratropical cyclones by strengthening whenever an upper-level shortwave came near, increasing baroclinicity. This study looks at the large-scale patterns of development and utilizes the diagnostic properties of the terms of the quasi-geostrophic omega equation to understand the forcings in the area of the cyclone as depicted in the North American Regional Reanalysis. In addition, cyclone phase diagrams were generated for other analyses to determine whether the characteristics depict hybrid, extratropical, tropical, or subtropical development based on the parameters of thermal wind and thermal symmetry. It was found that the system was a hybrid system in that a warm-core surface cyclone did exist from the surface to 500 hPa; however upper-level short waves about an upper-level trough were responsible for providing forcing for the genesis and strengthening of this storm.
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Date Issued: 2011
Identifier: FSU_migr_uhm-0038
Format: Thesis

Title: A Case Study of 2010 Hurricane Karl to Evaluate the Precipitation Forecasts of the Post Updated 2010 Global Ensemble Forecast System.
Creator: Day, Lindsey, Earth, Ocean & Atmospheric Science
Abstract/Description: This research project seeks to evaluate the rainfall forecast accuracy of the GEFS (Global Ensemble Forecast System) following the 2010 model update, analyzing the Atlantic September 2010 Hurricane Karl as a case study. Archived forecasted accumulated precipitation amounts from the GEFS are compared with archived CMORPH (CPC Morphing Technique) precipitation estimates. A sequence of 15 six hour forecasts from 1200 UTC 14 September 2010 to 1200 UTC 18 September 2010 are graphically displayed...
Show moreThis research project seeks to evaluate the rainfall forecast accuracy of the GEFS (Global Ensemble Forecast System) following the 2010 model update, analyzing the Atlantic September 2010 Hurricane Karl as a case study. Archived forecasted accumulated precipitation amounts from the GEFS are compared with archived CMORPH (CPC Morphing Technique) precipitation estimates. A sequence of 15 six hour forecasts from 1200 UTC 14 September 2010 to 1200 UTC 18 September 2010 are graphically displayed using GrADS (Grid Analysis and Display System). Four images were produced for each of the 15 six-hour time frames: A) CMORPH 6-hour accumulated precipitation, B) GEFS 6-hour accumulated precipitation, C) Difference in GEFS and CMORPH 6-hour accumulated precipitation (GEFS-CMORPH), and D) Overlay of outlined areas of medium (≥0.25 inches) and heavy (≥1.0 inches) precipitation for the GEFS and CMORPH. Several errors in the precipitation forecast of the GEFS model post-update were consistent with errors found in the GEFS model prior to its 2010 update from previous studies. For example, the GEFS forecasted the size of the hurricane to be too large for all evaluated times. Although the six hour GEFS track forecast was closely aligned with that of the verified track, major differences between the forecast and verification occurred as the storm approached its second landfall in Mexico. This study highlights that although the model may accurately depict the storm track, other model biases such as a lower resolution, difficulty depicting the atmosphere near land/sea boundaries and over complex terrain—may significantly impact the precipitation forecast.
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Date Issued: 2011
Identifier: FSU_migr_uhm-0011
Format: Thesis

Title: An Analysis of the Extratropical Flow Response to Recurving Atlantic Tropical Cyclones.
Creator: Brannan, Allison, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: There is a significant frequency of Atlantic tropical cyclones that complete extratropical transition and recurve in the mid-latitudes. Using a climatological approach, this study will analyze the extratropical flow response to recurving Atlantic tropical cyclones and compare the results to those from the Western North Pacific, as examined by Archambault et al. (2013). This investigation includes 54 recurving Atlantic tropical cyclones occurring between 2007 and 2013. The extratropical flow...
Show moreThere is a significant frequency of Atlantic tropical cyclones that complete extratropical transition and recurve in the mid-latitudes. Using a climatological approach, this study will analyze the extratropical flow response to recurving Atlantic tropical cyclones and compare the results to those from the Western North Pacific, as examined by Archambault et al. (2013). This investigation includes 54 recurving Atlantic tropical cyclones occurring between 2007 and 2013. The extratropical flow response will be quantified using potential vorticity. Characteristics of tropical cyclones, the extratropical jet stream, and the dynamical "phasing" of their interaction will be examined to determine the features that lead to significantly amplified extratropical flow. Results show the extratropical flow to be insensitive to the wind speed, latitude, and month of recurvature. However, there is an association between low mean sea level pressure and a larger amplification of flow. Finally, tropical cyclones recurving on the east side of the nearest trough are shown to have "favorable phasing," which yields amplification of the extratropical flow.
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Date Issued: 2015
Identifier: FSU_migr_uhm-0538
Format: Thesis

Title: Analysis of GFDL Intensity Forecasting Performance for Gulf/Caribbean Major Hurricanes from 1998-2008.
Creator: Hazelton, Andrew, Earth, Ocean & Atmospheric Science
Abstract/Description: While both computer model and official track forecasts of Atlantic Basin hurricanes have improved significantly over the past several decades, forecasts of intensity continue to prove difficult. Even specialized hurricane models struggle with predicting intensity. This study analyzes the intensity errors of the Geophysical Fluid Dynamics Laboratory (GFDL) Hurricane Model for 19 major hurricanes over the Gulf of Mexico and Caribbean Sea from 1998 to 2008. Using the measure of skill relative to...
Show moreWhile both computer model and official track forecasts of Atlantic Basin hurricanes have improved significantly over the past several decades, forecasts of intensity continue to prove difficult. Even specialized hurricane models struggle with predicting intensity. This study analyzes the intensity errors of the Geophysical Fluid Dynamics Laboratory (GFDL) Hurricane Model for 19 major hurricanes over the Gulf of Mexico and Caribbean Sea from 1998 to 2008. Using the measure of skill relative to the Statistical Hurricane Intensity Forecast (SHIFOR), the GFDL forecasts generally improved throughout most of the 11-year period, although there were some exceptions to this increase in skill. Comparing the GFDL to the Statistical Hurricane Intensity Prediction Scheme (SHIPS), it is found that the GFDL was slightly outperformed by SHIPS on most of the forecast categories and times. It seems that there is a correlation between higher intensity storms and higher errors (R = 0.53), and there is also a clear relationship between large negative errors and rapid intensification (R = 0.62). This relationship is explored for some of the ―higher-error‖ cases by comparing the GFDL forecast intensity progression with the actual intensity change. Hurricanes Dean (2007) and Felix (2007) are also analyzed in more detail, since both of these storms were exceptions to the general trend in increased skill from 2000-2008. It is hoped that this and further analysis will illuminate reasons for the model's difficulty with the intensity forecasts, and provide a basis for improving model forecasts and official forecasts of tropical cyclone intensity.
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Date Issued: 2011
Identifier: FSU_migr_uhm-0014
Format: Thesis

Title: Analysis of Convective Transport of Biomass Burning Emissions in Southeast Asia.
Creator: Ahern, Kyle, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: Biomass burning and anthropogenic emissions affect the composition of the atmosphere, thereby impacting global climate and health. Deep convective processes can loft emissions from the boundary layer into the upper troposphere or lower stratosphere (UTLS). Strong upper-level winds can potentially transport the emissions over long distances. This study focused on the deep convective transport of biomass burning emissions near the Strait of Malacca during summer. The Weather Research and...
Show moreBiomass burning and anthropogenic emissions affect the composition of the atmosphere, thereby impacting global climate and health. Deep convective processes can loft emissions from the boundary layer into the upper troposphere or lower stratosphere (UTLS). Strong upper-level winds can potentially transport the emissions over long distances. This study focused on the deep convective transport of biomass burning emissions near the Strait of Malacca during summer. The Weather Research and Forecasting (WRF) and Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT_4) models were used to investigate deep convection and the transport of emissions from fires in the region. Fire data from the Moderate-resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua and Terra satellites provided locations of fire emissions. These fire datasets were obtained from the University of Maryland's Fire Information for Resource Management System (FIRMS). To investigate the deep convective processes thoroughly, this study used high resolution modeling (4 km grid spacing) to resolve the convection explicitly. Explicit resolution allows the thunderstorms to be simulated more realistically than would parameterization, thus making it ideal for this research. Results showed that deep convection occurring in the Strait of Malacca is driven primarily by diurnal heating patterns and the region's topography. Convection in the region is frequent and scattered, but follows a cyclic diurnal pattern: convection over land during daytime and over the Strait during nighttime. When emissions from fires encounter areas of deep convection, they are quickly lofted to the UTLS where winds then transport them elsewhere.
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Date Issued: 2013
Identifier: FSU_migr_uhm-0216
Format: Thesis

Title: The Accuracy of the National Hurricane Center's United States Tropical Cyclone Landfall Forecasts in the Atlantic Basin (2004–2012).
Creator: Keclik, Alexandra, Department of Earth, Ocean and Atmospheric Sciences
Abstract/Description: This study examined the position, timing, and intensity of each National Hurricane Center's (NHC) Official Forecasts (OFCL) for Atlantic tropical storms and hurricanes that made landfall in the United States from 2004 to 2012. During that time period, one hundred and fifty tropical cyclones developed in the Atlantic basin. Thirty-two of the cyclones made landfall in the United States as tropical storms or hurricanes. Accurate predictions of the location, timing, and intensity of tropical...
Show moreThis study examined the position, timing, and intensity of each National Hurricane Center's (NHC) Official Forecasts (OFCL) for Atlantic tropical storms and hurricanes that made landfall in the United States from 2004 to 2012. During that time period, one hundred and fifty tropical cyclones developed in the Atlantic basin. Thirty-two of the cyclones made landfall in the United States as tropical storms or hurricanes. Accurate predictions of the location, timing, and intensity of tropical cyclone landfalls are important, so that people in a storm's track can prepare adequately for heavy to catastrophic wind, rain, and storm surge. The errors of each of the OFCL for Atlantic tropical storms and hurricanes that made landfall in the United States during 2004–2012 are acquired from the Best Track data set. The ELTOPO1 landmask is used to find the forecasted landfall point using sequential locations from the OFCL offshore and onshore points of each forecast. The great circle distance between the forecasted and actual landfall constitutes the location error. The official landfall time is subtracted from the forecasted landfall time to find the timing error, and the official landfall wind speed is subtracted from the closest to onshore wind speed to find intensity error. There is a trend of decreasing error in location, timing, and intensity forecasting with decreasing lead time. An improvement in tropical cyclone landfall forecasting is found from comparing the 2004–2012 Atlantic landfall forecast errors to those in a study of 1976-2000 forecasts.
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Date Issued: 2014
Identifier: FSU_migr_uhm-0324
Format: Thesis

Meteorology (19)	+ -
Atmospheric physics (13)	+ -
Oceanography (9)	+ -
Earth sciences (8)	+ -
Climate (3)	+ -

Data processing (1)	+ -
Fresh water (1)	+ -
Longitudinal method (1)	+ -
Probabilities (1)	+ -
Time-series analysis (1)	+ -

Department of Earth, Ocean and Atmospheric Sciences (11)	+ -
Earth, Ocean & Atmospheric Science (8)	+ -
Ahern, Kyle (1)	+ -
Blaskiewicz, Claire S. (1)	+ -
Brannan, Allison (1)	+ -

Dacey, Connor (1)	+ -
Day, Lindsey (1)	+ -
Freeman, Sean (1)	+ -
Hazelton, Andrew (1)	+ -
Heath, Nicolas (1)	+ -
Jackson, Karly M. (1)	+ -
Keclik, Alexandra (1)	+ -
McNaught, Carlysle (1)	+ -
Prugue, Rodrigo (1)	+ -
Rudzin, Johna (1)	+ -
Saunders, Matthew (1)	+ -
Sliwinski, Timothy (1)	+ -
Swearingen, Aaron D. (1)	+ -
Visin, Lauren (1)	+ -
Worsnop, Rochelle (1)	+ -
Zuromski, Lauren (1)	+ -

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