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Full catalog/CYGNSS_L2_SURFACE_FLUX_V3.2
CYGNSS_L2_SURFACE_FLUX_V3.2·v3.2·dataset

Heat moving between ocean and air (CYGNSS)

CYGNSS Level 2 Ocean Surface Heat Flux Science Data Record Version 3.2
ocean NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. How much heat is moving between the ocean surface and the air above it, mapped over the tropics and subtropics with about 25 km footprints.

How it's made. Derived from the CYGNSS constellation of small satellites, which sense ocean surface wind speed, combined with a weather reanalysis and a standard ocean-atmosphere algorithm.

How & where you'd use it. Supports research on tropical cyclones and how the ocean and atmosphere exchange energy, with frequent revisits that help capture fast-changing storm conditions.

What's measured

OCEANS › OCEAN HEAT BUDGET › HEAT FLUX › OCEAN SURFACE LATENT AND SENSIBLE HEAT FLUXESOCEANS › OCEAN TEMPERATURE › SEA SURFACE TEMPERATURE

Coverage & cadence

  • Time span2018-08-01 → ongoing
  • Measured byCYGNSS (DDMI)
  • Processing levelLevel 2
  • Spatial extent-180, -39.8, 180, 39.8
  • 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

The CYGNSS level 2 ocean surface heat flux science data record version 3.2 dataset is provided as a service to the oceanographic and meteorological research communities on behalf of the CYGNSS Science Team in direct collaboration with the Cyclone Global Navigation Satellite System (CYGNSS) Mission. CYGNSS was launched on 15 December 2016, it is a NASA Earth System Science Pathfinder Mission that was launched with the purpose of collecting the first frequent space‐based measurements of surface wind speeds in the inner core of tropical cyclones. Originally made up of a constellation of eight micro-satellites, the observatories provide nearly gap-free Earth coverage using an orbital inclination of approximately 35° from the equator, with a mean (i.e., average) revisit time of seven hours and a median revisit time of three hours. This dataset provides time-tagged and geolocated ocean surface heat flux parameters with 25x25 kilometer footprint resolution from the Delay Doppler Mapping Instrument (DDMI) aboard the CYGNSS satellite constellation. The reported sample locations are determined by the specular points corresponding to the Delay Doppler Maps (DDMs). Version 3.2 uses CYGNSS Level 2 (L2) Science Data Record (SDR) Version 3.2 surface wind speeds and ECMWF Reanalysis, Version 5 (ERA5). The Coupled Ocean-Atmosphere Response Experiment (COARE) algorithm is what is used in this dataset to estimate the latent and sensible heat fluxes and their respective transfer coefficients. While COARE's initial intentions were for low to moderate wind speeds, the version used for this product, COARE 3.5, has been verified with direct in situ flux measurements for wind speeds up to 25 m/s. As CYGNSS does not provide air/sea temperature, humidity, surface pressure or density, the producer of this dataset obtains these values from this dataset obtains these values from ERA5. This dataset is made available from 1 August 2018 to present with an approximate 1 week latency in the netCDF-4 formatted data files, where each file contains data within a 24-hour UTC period from a combination of up to 8 unique CYGNSS spacecraft. More information on CYGNSS can be found on the CYGNSS mission page.

Get the data

cygnss_l2_surface_flux_v3.2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CYGNSS_L2_SURFACE_FLUX_V3.2",
    version="3.2",
    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.