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Full catalog/CYGNSS_L2_SURFACE_FLUX_V2.0
CYGNSS_L2_SURFACE_FLUX_V2.0·v2.0·dataset

Heat moving between ocean and air (CYGNSS)

CYGNSS Level 2 Ocean Surface Heat Flux Science Data Record Version 2.0
ocean NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. How much heat and moisture pass between the sea surface and the air, mapped in about 25 km patches across the ocean.

How it's made. Produced from CYGNSS satellite wind-speed data combined with weather-reanalysis air and sea conditions (ERA5), run through the COARE ocean-atmosphere exchange model.

How & where you'd use it. Understanding how oceans give heat to the atmosphere, including in tropical storms; helps researchers study weather and climate over the sea.

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, -38, 180, 38
  • FormatsnetCDF-4
  • 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

This dataset contains the Version 2.0 CYGNSS Level 2 Ocean Surface Heat Flux Science Data Record, which 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 2.0 represents the second release of this product, which now uses CYGNSS Level 2 (L2) Science Data Record (SDR) Version 3.1 surface wind speeds and ECMWF Reanalysis, Version 5 (ERA5). Version 1.0 used CYGNSS L2 SDR Version 2.1 surface wind speeds and NASA Modern-Era Retrospective Analysis for Research and Applications Version 2 (MERRA-2). 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. The Cyclone Global Navigation Satellite System (CYGNSS), launched on 15 December 2016, is a NASA Earth System Science Pathfinder Mission that was launched with the purpose to collect the first frequent space-based measurements of surface wind speeds in the inner core of tropical cyclones. Made up of a constellation of eight micro-satellites, the CYGNSS observatories provide nearly gap-free Earth coverage with a mean (i.e., average) revisit time of seven hours and a median revisit time of three hours. As a result of the CYGNSS constellation coverage, this data 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_v2.0_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CYGNSS_L2_SURFACE_FLUX_V2.0",
    version="2.0",
    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.