Investigations of airborne laser scanning signal intensity on glacial surfaces – Utilizing comprehensive laser geometry modelling and orthophoto surface modelling (A case study: Svartisheibreen

• Main Authors: E. Lutz, Th. Geist, J. Stötter
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2003
• Subjects: KEY WORDS; Laser Scanning; Glaciology; Geometry; LIDAR; Snow Ice; GIS Modelling; Infrared; Intensity; Norway; Svartisen; glacier
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.154.9652; http://www.isprs.org/commission3/wg3/workshop_laserscanning/papers/Lutz_ALSDD2003.pdf

A comprehensive Geographic Information System (GIS) was developed to determine how the laser intensity of an Airborne Laser Scanning (ALS) system was affected by 1) geometry and 2) surface type. The study area contained the Svartisheibreen glacier (Svartisen, Norway) and its immediate surroundings. A model was created which contained laser intensity, surface type, surface elevation, and the scan geometry. The model utilized flight data, laser point-generated Digital Elevation Models (DEMs), and orthophotos as input. The main results include: 1) the primary cause of peripheral decreases in intensity values (i.e. cross-path fading) is geometry-dependent; this variation was effectively eliminated by developing Composite Laser Intensity Models (CLIMs); 2) By means of geographical and statistical analysis, the remaining primary variables influencing the signal intensity were identified as the range, the surface elevation and the surface type. Through this investigation it has been determined that laser intensity modelling can be effectively employed to identify surface characteristics and surface classes of glacial regions. These findings suggest that laser intensity imaging is a cost-effective alternative or addition to other optical devices such as digital cameras. 1.1 Primary Objective 1.