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Introduction

This site contains an overview of the NOAA services being provided by the National Oceanographic Data Center (NODC) for the Jason-2 satellite altimetry mission (note: Jason-2 is also known as the Ocean Surface Topography Mission or OSTM) and for Jason-3, which is scheduled for launch in April, 2014.

Background

The Jason-2 satellite launched 20 June 2008 and is the latest in a series of ocean altimeter missions designed to observe ocean circulation, sea level rise, and wave heights. Earlier altimeter missions include Geosat and Geosat Follow-On satellites, which flew in 1985-1989 and 1998-2008, respectively, and the TOPEX/Poseidon (1992-2005) and Jason-1 (2001-present) missions, which were launched into the same orbit now occupied by Jason-2. Jason-2 is currently flying in what is known as the "reference" orbit. Jason-1 continues to operate today in a similar "interleaved" orbit, offset by approximately 5 days and 0.7 degrees longitude at the equator from Jason-2.

Level-2 X-GDR Data Access

• HTTP: http://data.nodc.noaa.gov/jason2/
• FTP: ftp://ftp.nodc.noaa.gov/pub/data.nodc/jason2/
• OPeNDAP: http://data.nodc.noaa.gov/opendap/jason2/
• THREDDS: http://data.nodc.noaa.gov/thredds/catalog/jason2/catalog.html
• OSTM/Jason-2 and Jason-3 Products Handbook

Quality Monitoring of the Science Data

For deriving long-term quality measurements on Jason satellite data, we have developed a climate-oriented quality monitoring system. This system uses the Rich Inventory concept developed at NGDC, providing a searchable database for tracking and discovering data quality, metadata, and data set attributes. A near real time data quality check comprising of 8 statistics calculated on 23 parameters is performed as each Level-2 data file is ingested into NODC's archives.

• Quality Monitoring: Jason-2 GDR and IGDR quality monitoring

Frequently Asked Questions (FAQ)

• What is the difference between the OGDR, IGDR and GDR?

  A. The Operational Geophysical Data Record (OGDR) is produced within 1-2 hours of the satellite overflight. It has the lowest quality data and the most missing data. However, it is useful for time-critical applications. The Interim GDR is produced within 1-2 days of overflight. The orbital quality is far better. The science-quality "final" GDR is produced with a 60-day time lag. Note: A new, experimental OGDR is being produced at JPL within 7-9 hours of overflight. The quality of orbital information is equivalent to that of the IGDR. It is listed below.

Archive Details

1. Requirements
2. Strategy
3. Submission Agreement
4. Services

Related altimeter datasets and products

These links will take you out of NODC and we have no control over the content or whether these sites are kept up-to-date. Note that many of these sites require you to create a username and password in order to access the data.

• RADS (Radar Altimeter Database System) *
• High-quality experimental OGDRs from JPL. Note for RADS users: RADS incorporates these.
• Jason-1
• Jason-2
• Envisat
• CTOH: high-frequency along-track data and coastal products
• PISTACH: experimental coastal products for Jason-2
• CNES Data Center a sister site with the official Jason-2 xGDRs, auxiliary and ancillary data as well as similar records for TOPEX/Poseidon, Jason-1, Envisat, and Cryosat. Hosted by AVISO.
• AVISO (gridded products and improved delayed-mode products)
• LSA CryoSat IGDR: The NOAA/NESDIS Laboratory for Satellite Altimetry has been producing Level-2 IGDR from CryoSat mission and provides anonymous ftp access to the data