LiDAR (Light Distance And Ranging, a.k.a. ALSM (Airborne Laser Swath Mapping)) data is quickly becoming one of the hottest tools in the Geosciences for studying the earth’s surface. Capable of generating digital elevation models (DEMs) more than an order of magnitude more accurate than those currently available, LiDAR data offers geologists the opportunity to study the processes the shape the earth’s surface at resolutions not previously possible.

Unfortunately, access to these datasets for the average geoscience user is currently difficult because of the massive volumes of data generated by LiDAR. Distribution, interpolation and analysis of large LiDAR datasets, which frequently exceed a billion data-points, present significant computational challenges. We are using a geoinformatics approach to the distribution, interpolation and analysis of LiDAR data that capitalizes on cyberinfrastructure being developed as part of the GEON project. We utilize a comprehensive workflow-based solution that begins with user-defined selection of a subset of point cloud data and ends with download and visualization of interpolated surfaces and derived products.

In this GEON-based workflow, the billions of points within a LiDAR point cloud are hosted in an IBM DB2 spatial database running on the DataStar terascale computer at San Diego Supercomputer Center; a machine designed specifically for data intensive computations. Data selection is performed via an interactive-map interface that allows users to execute spatial and attribute subset queries on the larger dataset. The subset of data is then passed to a GRASS Open Source GIS-based web service that handles interpolation to grid and analysis of the data. Users may choose to download their results in ESRI or ascii grid formats as well as geo tiff. The workflow also feeds into GEON web services in development that will allow visualization of workflow outputs in either a web browser window or in 3D.

To use the GEON LiDAR workflow, go to the GEON Portal, log in (or register), then select the "GEON tools" tab.

For more information about ALSM and ALSM processing, visit the LIDAR/ALSM research pages from the Active Tectonics Group at Arizona State University.