U.S. Map Template

Explanation of our Standard U.S. Map Template

Coverage scales, text sizes and line widths for the standard U.S. map template have been set primarily with page size (8 1/2 by 11 inch) map products in mind. Coverages were set to scales that would make maximum use of the available space while still allowing sufficient room for titles, legends and other descriptive information. All coverages are in ALBERS EQUAL AREA projection using a NAD27 datum, a CLARKE1866 spheroid and map units in meters. The following coverages appear in the U.S. national standard template:

Coverage Map Scale Map Position (x/y page coordinates. in inches) Latitude Origin Central Meridian Standard Parallels
U.S. Contiguous 48 States 1:20,000,000 x=-0.1 y=1.0 23ºN 96ºW 29º0'N 45º0'N
Hawaii 1:20,000,000 x=0.05 y=2.75 20º3'45"N 157º3'45"W 19º6'15"N 21º4'15"N
Alaska 1:40,000,000 x=-0.1 y=0.40 50ºN 154ºW 55ºN, 65ºN
Puerto Rico and the U.S. Virgin Islands 1:10,000,000* x=8.17 y=0.47 18ºN 66º5'W 17º2'30"N 18º0'N
Guam and the Northern Marianas 1:10,000,000 x=0.12 y=1.60 0ºN 155ºE 12ºN, 15ºN
American Samoa 1:10,000,000 x=0.12 y=1.22 0ºN 170ºW 12ºS, 15ºS

*Some of our maps use an earlier version of the standard U.S. map template which shows Puerto Rico and the Virgin Islands at a 1:20,000,000 scale.

Since the scales of Puerto Rico, the U.S. Virgin Islands, and the Pacific Basin (Guam, Northern Marianas, American Samoa) are set to 1:10,000,000, their areal extents are exaggerated four times relative to that of the U.S. 48 contiguous States and Hawaii at 1:20,000,000. Conversely, Alaska at 1:40,000,000 scale has an areal extent that is understated by four times relative to the U.S. 48 contiguous States and Hawaii. These compromises were made to keep polygon boundaries and internal polygon shading clearly discernable for the smallest polygons we typically use (counties, 8-digit hydrologic units, and Major Land Resource Areas) without unnecessarily exaggerating or understating the areal extent relative to the other coverages (beyond what is required to promote discernability). One ought keep in mind that, if Alaska were to be scaled the same as Puerto Rico or the Pacific Basin, it would appear 16 times larger than it now does.

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