A CYBERINFRASTRUCTURE-BASED PORTAL FOR TOPOGRAPHIC DATA ACCESS, PROCESSING AND COMMUNITY INTERACTION

Over the past decade, there has been dramatic growth in the acquisition of publicly funded high-resolution topographic and bathymetric data for scientific, environmental, engineering and planning purposes. Because of the richness of these datasets, they are often extremely valuable beyond the initial application that drove their acquisition and thus are of interest to a large and varied user community. However, because of the massive volumes of data produced by high-resolution mapping technologies such as LiDAR, it is often difficult to manage and distribute these datasets via the Internet. Furthermore, the datasets can be technically challenging to work with, requiring specific software and computing resources that are not readily available to many users. Through a variety of cyberinfrastructure tools, we have launched an initiative to build an online portal (the Open Topography Portal – OpenToPo – www.opentopography.org) that provides integrated access to high-resolution topographic data, web-based processing tools, and enables the community of users to share knowledge, experiences and resources. The Open Topography Portal builds upon the cyberinfrastructure-based system developed in the GEON LiDAR Workflow (GLW) project during four years of collaboration between earth scientists at Arizona State University and computer scientists at San Diego Supercomputer Center.

The Open Topography Portal will use the GEON LiDAR Workflow as its core cyberinfrastructure-based system to provide online access to multi-billion point, high-resolution, LiDAR topography datasets. To address the distribution of both LiDAR point data as well as standard, high-resolution digital elevation models (DEMs) produced from LiDAR and provided by the data vendor, we have developed multiple pathways for users to access data. We employ a Google Maps and/or Google Earth-based interface to allow users to browse and download standard tiled digital elevation data. For users who wish to explore the full potential of the LiDAR data, we provide access to the raw LiDAR point data as well as a suite of DEM generation tools to enable users to generate custom DEMs to best fit their science applications. Through these multiple pathways, we are able to service various user communities and thereby democratize access to these challenging community datasets.

Given the diverse applications of these datasets, the relative inexperience of the user community and technical difficulty of working with the data, the Open Topography Portal aims to offer not only access to data and processing tools, but also to provide an environment for users to learn about the datasets, processing, and to network and interact with fellow users. The OpenToPo portal will utilize blogs, discussion forums and wikis to encourage communication and interaction between users. We also hope to leverage the collective knowledge of the user community to build a system that provides processing recommendations and guidance based on what other users have done.

Currently, the Open Topography Portal serves five datasets totaling over seven billion data points and approximately 2.5 TB. This system has been selected as the primary distribution pathway for LiDAR data acquired by the GeoEarthScope component of the NSF-funded EarthScope project (which will entail more than 20 billion additional points and a significantly larger user community). The Open Topography Portal's predecessor, the GEON LiDAR Workflow, has over 180 users who have processed over 49 billion LiDAR returns and downloaded more than 6000 DEM tiles. Future Open Topography Portal development includes expanding the dataset distribution and processing approach to develop a more generic workflow that will permit users to query, process, and calculate common derivatives for DEMs of various resolutions and origins. We are currently actively seeking collaborations to host additional datasets in the system.