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Global Navigation Satellite System (GNSS) IGS Predicted Ionosphere Vertical Total Electron Content (VTEC) Grid Product from NASA CDDIS

Metadata Updated: September 19, 2025

This derived product set consists of Global Navigation Satellite System Predicted Ionosphere Vertical Total Electron Content (VTEC) product (daily files) from the NASA Crustal Dynamics Data Information System (CDDIS). The VTEC product files also include Delay Code Bias (DCB) values for GNSS satellites and ground receivers derived during the analysis. GNSS provide autonomous geo-spatial positioning with global coverage. GNSS data sets from ground receivers at the CDDIS consist primarily of the data from the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS). Since 2011, the CDDIS GNSS archive includes data from other GNSS (Europe’s Galileo, China’s Beidou, Japan’s Quasi-Zenith Satellite System/QZSS, the Indian Regional Navigation Satellite System/IRNSS, and worldwide Satellite Based Augmentation Systems/SBASs), which are similar to the U.S. GPS in terms of the satellite constellation, orbits, and signal structure. GNSS observations from a global network can be utilized for atmospheric measurements. Analysis Centers (ACs) of the International GNSS Service (IGS) retrieve GNSS data on regular schedules to produce independently computed VTEC maps. The IGS Ionosphere Analysis Center Coordinator (ACC) uses these individual AC solutions to generate the official IGS VTEC maps. The predicted VTEC maps are computed with a resolution of 2 hours in UT, 5 degrees in longitude and 2.5 degrees in latitude; they are available in a one and a two day predicted product set.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher CDDIS
Maintainer
Identifier 10.5067/GNSS/GNSS_IGSIONOPTEC_001
Data Last Modified 2025-09-11
Category Earth Science
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 8f7883c3-bb93-4ff6-b2bd-82c97c24bcca
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://cddis.nasa.gov/archive/gnss/products
Old Spatial "CARTESIAN",{"WestBoundingCoordinate":-180,"NorthBoundingCoordinate":90,"EastBoundingCoordinate":180,"SouthBoundingCoordinate":-90}
Program Code 026:000
Source Datajson Identifier True
Source Hash a9883b4392c940a6678fb7903869e76a72d7eea6c3fbdcaad94fb827bd6affe3
Source Schema Version 1.1
Spatial
Temporal 1998-01-01/1998-01-01

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