What are Authoritative Topographical Maps?
Authoritative maps refer to high definition maps produced through a combination of hyper-accurate imaging, nuanced post-processing and color matching, exacting georeferencing, and assured curation. The W.E. Upjohn Center for the Study of Geographical Change has invented the authoritative digital topographic map.
Although at nominal 1:24,000 (1 in. = 2,000 ft.) scale, these maps can be used
with digital ortho-images (such as NAIP) and retain their geometric accuracy to at least 1:6,000 (1 in. = 500 ft.) scale. Our authoritative topographic maps tile together seamlessly, are produced in several map projections, and can be used easily with Google Earth (or other earth viewers), or integrated into Geographic Information Systems.
For illustration, please see the accompanying downloadable jumbo postcard showing Flint, Michigan's "Buicktown" on a 2009 NAIP image, a "current" USGS 24k map, and a 60 percent transparency overlay of the map on the image.