Global Navigation Satellite System (GNSS) Troposphere Zenith Path Delay (ZPD) product from NASA CDDIS

Metadata Updated: November 5, 2019

This derived product set consists of Global Navigation Satellite System Final Troposphere Zenith Path Delay (ZPD) Product (daily files by station) from the NASA Crustal Dynamics Data Information System (CDDIS). 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. Analysis Centers (ACs) of the International GNSS Service (IGS) retrieve GNSS data on regular schedules to produce troposphere ZPD estimates for stations of the IGS network. The primary troposphere products generated from ground-based GNSS data are estimates of total zenith path delay and north/east troposphere gradient. Ancillary measurements of surface pressure and temperature allow the extraction of precipitable water vapor from the total zenith path delay. The IGS Troposphere Analysis Center Coordinator (ACC) uses these individual AC solutions to generate the official IGS troposphere ZPD estimates for many of the stations in the IGS network. The final products consist of daily files containing data from each observing station. All ZPD solution files utilize the Solution INdependent EXchange format for combination of TROpospheric estimates (SINEX_TRO) and span 24 hours from 00:00 to 23:45 UTC.

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.

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Metadata Created Date February 28, 2019
Metadata Updated Date November 5, 2019

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date February 28, 2019
Metadata Updated Date November 5, 2019
Unique Identifier C1511696548-CDDIS
Maintainer Email
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Citation Archived by National Aeronautics and Space Administration, U.S. Government, NASA/GSFC/SED/ESD/GGL/CDDIS.
Harvest Object Id 4aa2e64d-0355-4b8b-8132-9072ad9cebe1
Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 2000-01-01
Homepage URL
Language en-US
Metadata Type geospatial
Data Last Modified 2018-04-09
Program Code 026:001
Source Datajson Identifier True
Source Hash 3b4d7c4355fd2ab71ce4b1583af08942eaa49962
Source Schema Version 1.1
Spatial -180.0 -90.0 180.0 90.0
Temporal 2000-01-01T00:00:00Z/2019-11-04T00:00:00Z
Category IGS, geospatial

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