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Full catalog/CYGNSS_L3_CDR_V1.2
CYGNSS_L3_CDR_V1.2·v1.2·dataset

Long-term ocean wind from GPS signals (CYGNSS)

CYGNSS Level 3 Climate Data Record Version 1.2
ocean NASA POCLOUD Level 3 active netCDF-4
In plain English

What it measures. A long-term, consistent record of average wind speed over the ocean, plus a measure of how rough the sea surface is, mapped on a grid covering the tropics and subtropics.

How it's made. The CYGNSS satellite constellation senses how GPS signals reflect off the sea surface, and those reflections were carefully reprocessed and averaged into a stable climate-quality record.

How & where you'd use it. Because it is tuned for long-term stability, it is well suited to studying how ocean winds change over years and to research on storms and ocean-atmosphere interaction.

What's measured

OCEANS › OCEAN WINDS › SURFACE WINDS › OCEAN SURFACE WIND SPEEDOCEANS › OCEAN WINDS › SURFACE WINDS

Coverage & cadence

  • Time span2018-08-01 → ongoing
  • Measured byCYGNSS (DDMI)
  • Processing levelLevel 3
  • Spatial extent-180, -40, 180, 40
  • 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 dataset contains the Version 1.2 CYGNSS Level 3 Climate Data Record which provides the average wind speed and mean square slope (MSS) on a 0.2x0.2 degree latitude by longitude equirectangular grid obtained from the Delay Doppler Mapping Instrument aboard the CYGNSS satellite constellation. The Level 2 Delay Doppler Map (DDM) data are used in the direct processing of the average wind speed and MSS data that are binned on the Level 3 grid. A subset of DDM data used in the direct processing of the average wind speed and MSS is co-located inside of the Level 2 data files. A single netCDF-4 data file is produced for each day of operation with an approximate 5 days latency. The reported sample locations are determined by the specular points corresponding to the Delay Doppler Maps (DDMs). The Version 1.2 CDR is a collection of reanalysis products derived from the SDR v3.1 Level 1 data (https://doi.org/10.5067/CYGNS-L1X31 ). Calibration accuracy and long term stability are improved relative to SDR v3.1 (https://doi.org/10.5067/CYGNS-L3X31 ) using the same trackwise correction algorithm as was used by CDR v1.1 (https://doi.org/10.5067/CYGNS-L3C11 ), which was derived from SDR v3.0 Level 1 data (https://doi.org/10.5067/CYGNS-L1X30 ). Details of the algorithm are provided in the Trackwise Corrected CDR Algorithm Theoretical Basis Document. CDR Level 2 and 3 products (ocean surface wind speed, mean square slope, and latent and sensible heat flux) are generated from the CDR L1 data using the v3.1 SDR data processing algorithms. These products also exhibit improved calibration accuracy and stability over SDR v3.1. Trackwise correction is applied to the two primary CYGNSS L1 science data products, the normalized bistatic radar cross section (NBRCS) and the leading edge slope of the Doppler-integrated delay waveform (LES). The correction compensates for small errors in the Level 1 calibration, due e.g. to uncertainties in the GPS transmitting antenna gain patterns and the CYGNSS receiving antenna gain patterns. It should be noted that the trackwise correction algorithm cannot be successfully applied to all SDR v3.1 L1 data so there is also some loss of samples that were present in SDR v3.1.

Get the data

cygnss_l3_cdr_v1.2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CYGNSS_L3_CDR_V1.2",
    version="1.2",
    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.