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Publicly Available Enhanced Elevation Data Map Sept 2011

2011 (approx.)

Detailed Description

Publicly Available Enhanced Elevation Data

Map showing results of the National Enhanced Elevation Assessment (NEEA) Elevation Data Inventory. The inventory was produced in partnership by the U.S. Geological Survey, National Oceanic and Atmospheric Administration, and Federal Emergency Management Agency in September 2011.

Enhanced elevation data includes light detection and ranging (lidar), interferometric synthetic aperture radar (ifsar), and photogrammetric elevation data. These data can be used to produce the 1/9 arc-second National Elevation Dataset (NED).

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Map Legend

Quality level—NPS, Nominal post spacing (in meters); RMSE, Root mean square error (in centimeters); <, less than

Dark Orange: 1—High accuracy (0.35 NPS, 9.25 RMSE)

Light Orange: 2—High to medium accuracy (0.7 NPS, 9.25 RMSE)

Yellow: 3 - Medium accuracy (1–2 NPS, <18.5 RMSE)

Light Grey: 4 - Medium to Low accuracy (5 NPS, 46–139 RMSE)

Light Olive: 5 - Low accuracy (5 NPS, 93–185 RMSE)

Dark Grey: Quality Unknown