Skip to main content

GNSS Product Holdings

Products derived from Global Navigation Satellite System (GNSS) data archived in NASA's Crustal Dynamics Data Information System Distributed Active Archive Center (CDDIS DAAC) are generated and submitted by the International GNSS Service (IGS) analysis and associate analysis centers. IGS products support scientific research in:

- Realization of the International Terrestrial Reference Frame (ITRF)
- Monitoring deformation of the solid Earth
- Monitoring Earth rotation
- Monitoring variations in the hydrosphere (sea level, ice sheets, etc.)
- Scientific satellite orbit determination
- Monitoring the Earth’s ionosphere and troposphere
- Time and frequency transfer

Data Summary

IGS operational products include precise GNSS satellite ephemerides, positions and velocities of stations in the global GNSS network, EOPs (polar motion and rates, length-of-day), and station and satellite clock solutions. Other products derived from the CDDIS GNSS data holdings include troposphere Zenith Path Delay (ZPD) estimates (both dry and wet components) and global ionosphere maps, both in support of IGS Working Groups or Pilot Projects.Spatial Coverage

Product Holdings

Temporal Coverage

  • GNSS orbit, station position, and EOP products since June 1992
  • Troposphere Zenith Path Delay (ZPD) products since January 1997
  • Ionosphere Total Electron Content (TEC) products since June 1998

Data Volume

  • Weekly and daily GNSS orbits, station position, and EOP files: ~1.8 Gbytes/week (compressed)
  • Daily troposphere files: ~3.7 Mbytes/day (compressed)
  • Daily ionosphere files: ~5.5 Mbytes/day (compressed)

Data Formats

Frequently Asked Questions

Earthdata Forum

Our online forum provides a space for users to browse thousands of FAQs about research needs, data, and data applications. You can also submit new questions for our experts to answer.

Submit Questions to Earthdata Forumand View Expert Responses

Earthdata
Forum