The National Map: Elevation

Elevation

Service Announcement: Changes with the delivery of NED 1- and 1/3-arc-second data, effective December 18, 2012.

Data: documentation and downloads
Status & highlights
Publications
Applications and examples
Other resources and activities

The National Elevation Dataset (NED) is a seamless raster product primarily derived from USGS 10- and 30-meter Digital Elevation Models (DEMs), and, increasingly, from higher resolution data sources such as light detection and ranging (lidar), interferometric synthetic aperture radar (ifsar), and high-resolution imagery. NED data are available from The National Map Viewer as 1 arc-second (approximately 30 meters) for the CONUS, and at 1/3 and 1/9 arc-seconds (approximately 10 and 3 meters, respectively) for parts of the United States. NED resolution for Alaska is primarily 2 arc-seconds (approximately 60 meters) but is rapidly being replaced with 5-meter resolution ifsar data State-wide and lidar over select areas. Lidar point cloud data is available for download from Earth Explorer.

In response to growing needs for high-quality topographic data and for a wide range of other three-dimensional representations of the Nation's natural and constructed features, the National Geospatial Program has introduced the 3D Elevation Program (3DEP) initiative, the goal of which is to systematically collect enhanced elevation data in the form of high-quality lidar data over the conterminous United States (CONUS), Hawaii, and the U.S. territories. Ifsar data will be collected over Alaska, where cloud cover and remote locations preclude the use of lidar over much of the State. The 3DEP initiative will result in higher resolution and more accurate data as well as new products in the future.

Data: documentation and downloads

National Elevation Dataset - Spatial Metadata
NED Data Dictionary, Release Notes, and ESRI shapefiles...

The National Map Viewer - download elevation data
Select the 'Elevation' theme within the 'Download Data' tool....see detailed instructions...

EarthExplorer - lidar point cloud data
An extensive user guide is available (PDF)...

USGS Center for Lidar Information Coordination and Knowledge (CLICK)
Locate and view publically available elevation data in your area of interest...see instructions...

Image of an 'all-return lidar point cloud' featuring the USGS Earth Resources Observation and Science (EROS) Center in Sioux Falls, SD.

Status & highlights

Latest National Elevation Dataset Update
The February, 2013 update of the National Elevation Dataset (NED) 1-, 1/3- and 1/9-arc-second collections were released on February 5, 2013. This marks the 70th update of the 1-arc-second layer since bi-monthly revisions began in June, 2000. This release incorporates 22,996 square miles of new light detection and ranging (lidar) data into the NED 1/9-arc-second layer. The NED 1- and 1/3-arc-second layers were updated with 18,613 square miles of migrated high-resolution source data.

The status graphic on the left (click for larger version) is one of several contained in the NED Release Notes for February, 2013 (PDF), which is published on a bi-monthly basis.
Elevation data for Rock County, Minnesota (and Blue Mounds State Park, featured below) is among the 9 Minnesota counties included in the latest update of the NED.

Blue Mounds State Park
Rock County, Minnesota
Blue Mounds State Park rises more than 30 meters (~100 feet) above the flat landscape of farms and the small community of Luverne, Minnesota. This cornucopia-shaped bluff consists of Sioux Quartzite, a dark-pink to dark-red, metamorphic rock of Precambrian age. This rock unit is also interbedded with a red to purple shale and catlinite, a metamorphic mudstone (argillite), also known as pipestone.
Pipestone has been used by Native Americans for centuries to make sacred pipes. A small quarry of catlinite is located just over 35 kilometers (~23 miles) to the north of Blue Mounds State Park, in Pipestone County, at the Pipestone National Monument.

References:

Matsch, C.L., et al. Minnesota. Minnesota Geological Survey. Field Trip Guidebook for Geomorphology and Quaternary Stratigraphy of Western Minnesota and Western South Dakota. Guidebook Series No. 7. St. Paul: Minnesota Geological Survey, University of Minnesota, 1972.
Page 6.

Publications

The 3D Elevation Program - Summary of Program Direction
USGS Fact Sheet 2012-3089

National Enhanced Elevation Assessment at a Glance
USGS Fact Sheet 2012-3088

Lidar Base Specification Version 1.0
USGS Techniques and Methods 11-B4; August 2012

The National Map - Elevation
USGS Fact Sheet 2009-3053

The National Map - Elevation
USGS Multimedia Gallery (video); May 1, 2012

Creation of Digital Contours That Approach the Characteristics of Cartographic Contours
USGS Scientific Investigations Report 2012-5167

Mount St. Helens lidar (cover: ····>)
USGS General Information Product 116; November 2010

High-resolution lidar image of Mount St. Helens, Washington

Graphic representation of topo-bathymetric data for Mobile Bay, Alabama

Frame from lidar imagery video identifying the Mt. Tallac Fault, California.

Applications and examples

TopoBathy—merging topography (elevation) and bathymetry (water depth) into a seamless elevation product: The initial dataset (left) is centered over Mobile Bay, Alabama and was constructed using a combination of 71 disparate topographic and bathymetric datasets from the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), and the U.S. Army Corps of Engineers (USACE)
The National Atlas: Topographic Maps Illustrating Physiographic Features: Demonstrates how many map features are recreated on topographic maps using contours
Treatment of Hydrographic Features in lidar data (PPT; 5.6MB): Interactively (see slide 8) displays techniques used to adjust lidar data anomalies over surface water areas
USGS Topographic Science: Research and applications that facilitate the development and use of integrated national and global topographic datasets
Using bare-earth lidar imagery to reveal the Tahoe-Sierra frontal fault zone, Lake Tahoe, California: A video demonstrating how airborne lidar imagery can penetrate dense forest cover to reveal an active fault line not detectable with conventional aerial photography.

Other elevation data resources and activities

National Enhanced Elevation Assessment

United States Interagency Elevation Inventory

NOAA Digital Coast

USACE National Coastal Mapping Program

National Resources Conservation Service (NRCS) Data Gateway

Hydrography treatments of lidar-dem data (links to ppt; 5.6mb)