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Full catalog/JASON_3_L2_OST_OGDR_GPS
JASON_3_L2_OST_OGDR_GPS·vG·dataset

Sea surface height from orbit, live (Jason-3)

Jason-3 GPS based orbit and SSHA OGDR
ocean NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. Reports sea surface height anomalies, meaning how much the ocean surface is higher or lower than its usual level, along with the satellite's precisely calculated orbit position.

How it's made. Generated from NASA/partner Jason-3 altimeter measurements in a near-real-time mode, with the satellite's position pinned down using GPS for extra accuracy; it reaches users about five hours after observation.

How & where you'd use it. Used to watch ocean conditions like currents, eddies, and sea level changes close to real time, where the more accurate GPS-based orbit gives better height estimates.

What's measured

OCEANS › SEA SURFACE TOPOGRAPHY › SEA SURFACE HEIGHT › NONEOCEANS › OCEAN WAVES › SIGNIFICANT WAVE HEIGHT › NONE

Coverage & cadence

  • Time span2020-10-29 → ongoing
  • Measured byJASON-3 (AMR, GPSP, POSEIDON-3)
  • Processing levelLevel 2
  • Spatial extent-180, -66, 180, 66
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

This is a near real time dataset that provides a GPS based orbit and Sea Surface Height Anomalies (SSHA) from that orbit. It is similar to the Jason-3 Operation Geophysical Data Record (OGDR) that is distributed at NOAA (http://www.nodc.noaa.gov/sog/jason/), but includes the GPS orbit and SSHA as two additional variables. It has a 5 hour time lag due to the time needed to calculate the GPS orbit and SSHA. The GPS orbits have been shown to be more accurate than the DORIS orbits on a near real time scale and therefore produces a more accurate SSHA. Forward stream transitioned from processing baseline/version "F" to "G" in January 2025. The change is reflected in the product filename: JA3_GPSOPR_2P<b>f</b>S* -> JA3_GPSOPR_2P<b>g</b>S*

Get the data

jason_3_l2_ost_ogdr_gps_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="JASON_3_L2_OST_OGDR_GPS",
    version="G",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from POCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.