This dissertation adds to ongoing research efforts that seek a better understanding of the complex relationships between human beings and their environment. Specifically, the impact of natural disasters on coastal communities from the sudden occurrences of such disasters and their potentially devastating consequences - e g., earthquakes and tsunamis - requires communities to be prepared, by planning specific land-use polices and by developing evacuation plans. Through identifying the locations of populations at risk of a tsunami, determining their behavioral responses during an evacuation, and utilizing a GIS evacuation tool - Capacity-Aware Shortest Path Evacuation Routing (CASPER), the research reported in this dissertation proposes a means to predict the number of evacuating vehicles from various tsunami scenarios and calculate evacuation clearance time for these scenarios. Motivated by the need to provide new ways to use the results of the behavioral analysis in evacuation modeling, this study developed a methodology to predict the number of evacuating vehicles based on the result of the behavioral analysis to estimate the evacuation clearance time using evacuation modeling. In order to estimate the evacuation clearance time, a framework was utilized and is described in four analytical chapters of this dissertation - chapters 4 - 7: Chapter 4 identifies the population at risk of tsunami. Chapter 5 explores the characteristics of the sample population; Chapter 6 offers predictions on the number of evacuating vehicles, and, Chapter 7 models the evacuation process to estimate the evacuation clearance time with and without congestion. Each of these chapters interconnects with the succeeding chapter as they together complete the framework used to model evacuation clearance time. The ability to assess the preparedness for a natural hazard will broaden the understanding of the relationship between behavioral responses and evacuation transportation options, which in turn will provide planners, government officials, and geographers the required knowledge to address related planning issues such as evacuation planning and sustainable development.