Horn and Petit Bois islands are two of five Mississippi (MS) barrier islands that provide physical protection from tropical cyclones threatening the MS Gulf Coast, in addition to critical habitat for the northern Gulf of Mexico (GOM). In September 2004, Hurricane Ivan removed a large volume of sediment from the eastern ends of Horn and Petit Bois islands with its 1-2 m storm surge and ~194 kph wind speeds. Then, in August 2005 Hurricane Katrina severely impacted the two islands again with its 3.5-5.5 m storm surge on Horn and Petit Bois islands, and up to 204 kph wind speeds at landfall. Using topographic light detection and ranging (LIDAR) datasets from 2004 to 2016, spatial and temporal changes of the islands' area, sediment volumes, and shorelines were measured to ascertain their geomorphic responses and recovery rates following the impacts of these devastating tropical cyclones. During the 2004-05 hurricane seasons, Horn Island lost 13.3% of its pre-hurricane Ivan land area, lost 35.9% sediment volume, and had a total average shoreline change rate of-10 m/yr. Petit Bois Island lost 13.3% of its pre-Ivan land area, lost 27% sediment volume, and had a shoreline change rate of-33 m/yr. Between 2005 (post-Katrina) and 2016, Horn Island recouped 6.6% of its pre-Ivan land area and ~4.3% sediment volume, while Petit Bois Island recovered 4% of its pre-Ivan land area and ~22.9% sediment volume. The overall averaged shoreline change rates between 2004 and 2016 were-2 m/yr for Horn Island and-3 m/yr for Petit Bois Island. These changes reflect that Horn Island is no longer stable, as its sediment supply cannot keep pace with the current rate of sediment loss, and that because Petit Bois Island's narrow central shoreline is retreating at a rate of ~9 m/yr, the island is at risk of breaching during the next storm. iv ACKNOWLEDGMENTS The success of this research project was made possible from the support of many individuals. I would first like to thank my advisor and committee chair, Dr. Davin Wallace, and co-advisor, (late) Admiral (ret.) Kenneth Barbor. Their visions of coastal mapping and analyses for maritime, geological, and coastal management purposes have made this research possible. Thank you for providing me guidance and insight on coastal processes, LIDAR applications for coastal management, and pushing me to learn skills I was previously unfamiliar with. Next, I'd like to thank my two committee members, Dr. Stephan Howden and Dr. Maarten Buijsman. They continually provided their expertise on physical processes, wave energy, and wave dynamics in the coastal zone. Their insight was beneficial for my understanding of some of the math that went into calculating wave energy and the impact the magnitude of energy has on barrier island geomorphology. Thank you to the research technicians and students who have assisted me in overcoming various software and physics challenges. Samuel Wright offered his time, patience, and mentorship by teaching me the ins and outs of MATLAB and ArcGIS. He was also kind enough to proofre...

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