Proceed to GeoCommunity Home Page


SpatialNewsGIS Data DepotGeoImaging ChannelGIS and MappingSoftwareGIS JobsGeoBids-RFPsGeoCommunity MarketplaceGIS Event Listings
HomeLoginAccountsAboutContactAdvertiseSearchFAQsForumsCartFree Newsletter

Sponsored by:


TOPICS
Download Data

Accounts

USGS DRGs

USGS DEMs

USGS DOQQs

FEMA Flood Data

VMAP

NWI

Gazetteer

Census/TIGER

Index Grids

About Data

Contact


SpatialNews Daily Newswire!
Subscribe now!

Latest Industry Headlines
Esri Challenge Winners Tell Visual Stories of Poland Elections, Global Terrorism, and More
Major California Water Utility Experiences Significant Savings Using Technology Solution from Trimble and Badger Meter
A New Final Version of i3Geo Has Been released: i3Geo 6.0
Arithmetica Simplifies Scan to CAD Workflow with Latest Release of Pointfuse
Louisiana Quads Add Trails and Survey Data

Latest GeoBids-RFPs
Spatial Data Report*Canada
LiDAR and Aerial Orthoimagery -NY
Spatial Data Synthesis
Mapping Software*Estonia
GPS System Install

Recent Job Opportunities
Senior GIS Programmer Analyst
Specialist, Enterprise Support (GIS)

Recent Discussions
Drawing GIS District Boundaries
How to draw farm boundaries on google maps?
Phone replacement for SQLServer Geometrybuilder?
What we CANT map?
Global Mapper vs. ESRI
USGS National Elevation Dataset (NED)

Coverage: Complete Coverage of Contintental US, AK, and HI
Size: 40 GB (Compressed) 56GB Uncompressed
Format: ArcGrid

The data is grouped in 2 degree latitude by 6 degree longitude blocks. The blocks are named in the following format xxxyy, where xxx is the longitude (may only be 2 characters) and yy is the latitude (always 2 characters).
Click Here for the Block Coverage Graphic (Continental US Only)


Product Description:
The NED is a new raster product assembled by the U.S. Geological Survey. NED is designed to provide National elevation data in a seamless form with a consistent datum, elevation unit, and projection. Data corrections were made in the NED assembly process to minimize artifacts, perform edge matching, and fill sliver areas of missing data. NED has a resolution of one arc-second (approximately 30 meters) for the conterminous United States, Hawaii, and a resolution of two arc-seconds for Alaska.

NED data sources have a variety of elevation units, horizontal datums, and map projections. In the NED assembly process the elevation values are converted to decimal meters as a consistent unit of measure, NAD83 is consistently used as horizontal datum, and all the data are recast in a geographic projection. Older DEM's produced by methods that are now obsolete have been filtered during the NED assembly process to minimize artifacts that are commonly found in data produced by these methods. Artifact removal greatly improves the quality of the slope, shaded-relief, and synthetic drainage information that can be derived from the elevation data.


Sponsored by:

For information
regarding
advertising rates
Click Here!

Copyright© 1995-2014 MindSites Group / Privacy Policy

GeoCommunity™, Wireless Developer Network™, GIS Data Depot®, and Spatial News™
including all logos and other service marks
are registered trademarks and trade communities of
MindSites Group