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Full catalog/TOPEX_ALTSDR
TOPEX_ALTSDR·vA·dataset

Raw sea surface height radar data (TOPEX)

TOPEX ALTIMETER SENSOR DATA RECORD
ocean NASA POCLOUD Level 1B RAW
In plain English

What it measures. Raw sea-surface-height radar data from the TOPEX altimeter, including the full radar return 'waveforms' that capture the detailed shape of each echo bouncing off the ocean.

How it's made. A low-level sensor data record, similar to the standard altimetry product but keeping the waveforms needed for fine reprocessing ('retracking').

How & where you'd use it. An expert-level product for those who need the raw waveforms; if you just want sea surface height, the standard GDR product is the better choice.

What's measured

OCEANS › OCEAN WAVES › WAVEFORM

Coverage & cadence

  • Time span1992-09-25 → 2005-10-04
  • Measured byTOPEX/POSEIDON (TMR, ALT (TOPEX))
  • Processing levelLevel 1B
  • Spatial extent-180, -66, 180, 66
  • FormatsRAW
  • StatusCOMPLETE

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

The Sensory Data Record (SDR) is similar to the GDR product except that it also contains waveforms, which are required for retracking. This is an expert level product. If you do not need the waveforms then the GDR should suit your needs.

Get the data

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

results = earthaccess.search_data(
    short_name="TOPEX_ALTSDR",
    version="A",
    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.