---

Product and Service Descriptions

• Aerial Photos

  Aerial photographs are used for a variety of positioning applications, including delineating the shoreline, and determining the precise locations of obstructions to, as well as aids to, air travel. Read more details about the availability, history and format of these photos.

• Aeronautical Data

  This data includes runway, navigational aid, obstruction, and other aeronautical data needed to operate the National Airspace System.

• Calibration Base Lines for EDMI

  Highly accurate base lines that provide a locally accessible standard for length measurement. NGS assists local organizations in establishing these base lines, which provide a means to detect and correct errors in Electronic Distance Measuring Instruments (EDMI)

• CARIB97

  Modeled geoid height values with a 2-minute by 2-minute spacing in latitude and longitude, covering the Caribbean Sea and surrounding regions. CARIB97 includes software program GEOID for extracting and interpolating values from the model to discrete points.

• Contracted Projects

  Provides summaries of the surveying and mapping work NGS is contracting out. These include aerial photography over airports, aerial photography over U.S. shoreline, geodetic control at airports, shoreline mapping, and height moderniztion projects.

• CORS: GPS Continuously Operating Reference Stations

  A nationwide network providing GPS data for a variety of postprocessing uses (after-the-fact positioning of fixed points and moving platforms).

• Data Sheets

  NGS' principal information product, the data sheet, combines control-point position and height information in a single format. Datasheets are retrieved directly from the NGS database by specifying a PID (Permanent Identifier), control point name, area, or survey project identifier. Control point information may be formatted in the traditional NGS Data Sheet Format, DSDATA (samples), or in the Spatial Data Transfer Format, Part 6: Point Profile.

  NGSmap provides a map interface for data sheet retrieval.

• DCAR97

  A model of surface deflection of the vertical values, with a 2-minute by 2-minute spacing, covering the Caribbean Sea and surrounding regions. DCAR97 includes software program DEFLEC for extracting and interpolating values from the model to discrete points.

• DEFLEC99

  A model of surface deflection of the vertical values, with a 1-minute by 1-minute spacing. DEFLEC99 was derived from the GEOID99 geoid model. DEFLEC99 includes software programs XNTD and INTD for extracting and interpolating values from the model to discrete

• DMEX97

  A model of surface deflection of the vertical values, with a 2-minute by 2-minute spacing, covering Mexico and surrounding regions. DMEX97 includes software program DEFLEC for extracting and interpolating values from the model to discrete points.

• Geodetic PC Software

  Free PC software developed by NGS and available for download

• GeodeticTool Kit

  On-line interactive computation of geodetic values, including: DEFLEC99, G99SSS, GEOID99, GEOID03, HTDP, NADCON, OPUS, State Plane Coordinate, Surface Gravity Prediction, Tidal and Orthometric Elevations, VERTCON

• Geodetic and Charting Publications booklet

  This booklet lists publications offered by the National Geodetic Survey and their prices. Listed publications may be ordered from the NGS Information Center.

• GEOID99

  Modeled geoid height values with a 1-minute by 1-minute spacing in latitude and longitude suitable for the conversion of NAD 83 ellipsoid heights into NAVD 88 orthometric heights. GEOID99 includes software programs XNTG and INTG for extracting and interpolating values from the model to discrete points. INTD is also available on line for interactive computations over the web. GEOID99 replaces the existing GEOID96 product.

• GEOID03

  GEOID03 is an update of the GEOID99 model. GEOID03 covers the coterminous U.S., Alaska, Hawaii, and Puerto Rico/Virgin Islands

• GEOID06

  GEOID06 is an update of the GEOID99 model. GEOID06 currently covers only Alaska

• GEOID09

  GEOID09 is an update of the GEOID99 model. GEOID09 currently covers the United States and other territories, and supersedes the previous models GEOID06, GEOID03, GEOID99, GEOID96, GEOID93, and GEOID90.

• G99SSS Gravimetric Geoid Model

  A geocentric gravimetric geoid model for the conterminous United States incorporating the latest data and geoid theory. G99SSS replaces the existing G96SSS model.

• Geoid, Gravity, Deflections, and Data Coverage Grids

  ASCII data grids in compressed format for researchers.

• GPS Antenna Calibration

  GPS antenna offsets and phase variations required for precise GPS surveys.

• GPS Orbital Data

  Orbital data for the Global Positioning System (GPS) satellite constellation

• Guide to Products and Services

  A brochure providing an overview of the Products and Services available from the National Geodetic Survey. [in pdf format]

• Metadata

  Geospatial metadata elements for geodetic data

• MEXICO97

  Modeled geoid height values with a 2-minute by 2-minute spacing in latitude and longitude, covering Mexico and surrounding regions. MEXICO97 includes software program GEOID for extracting and interpolating values from the model to discrete points.

• NOAA Shoreline Data Explorer

  The NOAA Shoreline Data Explorer is part of NGS's Coastal Mapping program. NGS is building a database of its digital shoreline holdings. Functions accessible through this location will support geographic browsing of the data base, and downloading of selected adata to the user's computer.

• NOS Data Explorer

  The NOS Data Explorer provides a map interface that retrieves a subset of NGS's control point datasheets and aerial photography in addition to many other National Ocean Services (NOS) products.

• Mark Recovery Entry Form

  Users of geodetic control data can now submit information on the condition of NSRS survey markers through this web site. See announcement for further information.

• Submitting Data for Inclusion into NSRS

  The National Geodetic Survey accepts other organization's survey data for inclusion into the National Spatial Reference System. Such data must meet stringent collection and format requirements.
  
  The article Data Processing in the National Geodetic Survey deals with the general format, computations and checking of control data which is submitted for inclusion in the National Spatial Reference System.
  

• Tidal and Orthometric Elevations

  The tidal information and orthometric elevations of a specific survey control mark can be viewed graphically. Displayed will be the differences between the published NAVD88 and NGVD29 and Mean Lower Low Water (MLLW) datums.

For more information contact NGS Information Services:
by email or call (301) 713-3242, Monday - Friday, 7:00 AM - 4:30 PM eastern time.