Isabel Garcia-Williams successfully defends dissertation

Congratulations to MANTIS and CMSS Ph.D. student Isabel Garcia-Willaims for successfully defending her dissertation, titled “Evaluation and Application of Mapping-Grade Mobile Lidar Scanning (MLS) for Coastal Zone Monitoring” on June 26, 2025.

During her time at MANTIS, Isabel’s research focused on assessing and utilizing a mapping-grade Mobile Lidar Scanning (MLS) system for monitoring sandy beach coastal corridor environments. Before her doctoral journey, Isabel received a Bachelor’s degree in Surveying Engineering with a minor in Mathematics from New Mexico State University and a Master’s degree in Geospatial Surveying Engineering from Texas A&M University-Corpus Christi.

PRESENTATION ABSTRACT

Vehicle-based mapping-grade mobile lidar scanning (MLS) systems collect high-resolution, three-dimensional point cloud data and allow for rapid deployment and flexible operation. They typically integrate a lidar scanner, mobile platform, position and orientation system (POS), camera, control system, and rigid mount. Unlike survey-grade MLS systems, which prioritize high precision, accuracy, and long-range scanning, mapping-grade systems generally integrate less capable lidar sensors and lower-grade POS components, resulting in relatively lower cost and a smaller form factor. These characteristics make mapping-grade MLS particularly useful for rapid deployment in coastal mapping and monitoring applications, where ease of use and mobility are important, and conditions are conducive to vehicle-based scanning. However, these benefits come with potential limitations, including reduced scanning range and lower positional accuracy and precision. Despite these limitations, mapping-grade MLS systems can provide accurate, detailed point cloud data of the beach and lower foredune, enabling the generation of high-resolution digital elevation models (DEMs) to support analysis of beach geomorphology, shoreline dynamics, sediment transport, coastal engineering projects, and post-storm impacts.

This study evaluates the application of a mapping-grade MLS system in sandy beach environments to support mapping and monitoring aimed at informing coastal management decisions. It is structured around three core objectives: (1) development of an optimized survey workflow for MLS system data collection and processing tailored to sandy beach corridors; (2) application of the workflow to assess shoreline position and geomorphic changes on a seawall-adjacent beach at North Padre Island, Texas, to guide bollard placement for vehicle access control and evaluate nourishment performance, including a comparative analysis of MLS and uncrewed aircraft system (UAS) photogrammetry for beach monitoring; (3) application of the workflow to assess seasonal vulnerability of Kemp’s ridley sea turtle (Lepidochelys kempii) nesting beaches along Padre Island National Seashore (PAIS) using an adapted Coastal Engineering Resiliency Index (CERI), supplemented by airborne lidar scanning (ALS) datasets for historical analysis. Overall, this work demonstrates the practical utility of mapping-grade MLS scanning in capturing coastal change and highlights its advantages, limitations, and potential for supporting coastal policy, resiliency planning, and resource management.