LIDAR and SRTM: A Case Study of The Naval Surface Warfare Center, DC

Abstract

Light detection and ranging (LIDAR) has been evolving for over forty years and has become a wide used technology that most people see or utilize almost daily. It was initially used as a ground based system to map particles in our atmosphere. This technology has spread into Archeology, Agriculture, Meteorology and Atmospheric Environment, Biology and Conservation, Law Enforcement, Autonomous driving, and the focus of this thesis is mapping. The main focus of this thesis is the process of mapping areas with LIDAR data and comparing the accuracy with older elevation data; Shuttle Radar Topography Mission, SRTM. For processing data, we go through four separate phases depending on your data and desired final product. Initially, it is recommended to perform quality checks, data preparation, derivative production, and finally editing the LAS files before distribution. The first product was processing raw LIDAR data and covering it with imagery for the Kameni Islands of the Santorini caldera in Greece. The main product was for the Naval Surface warfare Center outside of Washington DC along the Potomac River. I downloaded LIDAR data and cut an area of interest from Open Topography. I then downloaded imagery and SRTM data from United States Geological Survey, USGS, Earth Explorer for comparing the LIDAR data to Imagery and SRTM. Next, I was able to find survey control points in the region from the National Geodetic Survey, NGS, data explorer to compare the LIDAR data to the survey control points. We finally compared the final LIDAR data with SRTM data. SRTM data has larger point spacing and an accuracy of ~20 meter horizontal and ~10 meter vertical accuracy compared to the LIDAR data that is ~3 meter and between centimeter and decimeter vertical accuracy. There was also some data processing for terrestrial LIDAR survey for an area near Prescott, Arizona. Introduction This paper first explains what LIDAR is, how it is used, and the advancement of this technology towards better accuracy and efficiency of modern day mapping. First, the paper will explain what LIDAR is and how it has progressed to its current modern day technology. Then we will look at the different factors that make up LIDAR and how it factors in the final finished product. Finally, we will look at the products that are utilized and created to solve problems. Problem There are numerous elevation datasets available depending on the desired final product and location. LIDAR data is more accurate and denser than SRTM, DTED, etc. After finding the LIDAR data, depending on the data and final product, numerous different processes will need to be performed.