<title>Preliminary results of IFSAR/LIDAR analysis in the Lakewood, California area</title>

Abstract

Remotely sensed imagery can be used to assess the results of natural disasters such as floods. The imagery can be used to predict the extent of a flood, to develop methods to control a flood, and to assess the damage caused by a flood. This paper addresses the information derived from two different sources: Interferometric Synthetic Aperture Radar (IFSAR) and Light Detection and Ranging (LIDAR). The study will show how the information differs and how this information can be fused to better analyze flood problems. LIDAR and IFSAR data were collected over the same Lakewood area of Los Angeles, California as part of a Federal Emergency Management Agency (FEMA)-sponsored data collection. Lakewood is located in a floodplain and is of interest for updating the maps of floodplains. IFSAR is an active sensor and can penetrate through clouds and provides three separate digital files for analysis: magnitude, elevation, and correlation files. LIDAR provides elevation and magnitude files. However, for this study only the elevation values were provided. The LIDAR elevation data is more accurate and more densely sampled than the IFSAR data. In this study, the above information is used to produce charts with information relevant to floodplain mapping. To produce relevant information, the data had to be adjusted due to different coordinate systems, different sampling rates, vertical and horizontal post spacing differences, and orientation differences between the IFSAR and LIDAR data sets. This paper will describe the methods and procedures to transform the data sets to a common reference.