Comparing Maps a New Way
The positional accuracy of geospatial technologies has improved dramatically in the past few decades, and digital maps have replaced paper maps, making old ways of comparing maps obsolete.
Satellite and inertial positioning, aerial triangulation, lidar sensors and mobile mapping systems, interferometric synthetic aperture radar (IFSAR), unmanned aerial systems, and other key geospatial technologies have come a long way since the American Society for Photogrammetry and Remote Sensing (ASPRS) last revised its geospatial accuracy standards, more than 30 years ago. To catch up with the technology and fill a critical need for both map users and map makers, ASPRS recently released its new Positional Accuracy Standards for Digital Geospatial Data, available at asprs.org.
Traditionally, map users have relied on a map’s scale and contour interval as an indication of its accuracy, while map makers have relied on them to make diffi cult tradeoffs between accuracy and cost and to reliably and consistently describe their products.