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Full catalog/CYGNSS_L3_SOIL_MOISTURE_V3.2
CYGNSS_L3_SOIL_MOISTURE_V3.2·v3.2·dataset

How wet the soil is, from GPS bounce signals (CYGNSS)

CYGNSS Level 3 Soil Moisture Version 3.2
land NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. How wet the top few centimeters of soil are (volumetric water content) across much of the subtropics, updated roughly every six hours.

How it's made. Estimated by the CYGNSS satellites, which read GPS signals reflecting off the land; the wetness algorithm was calibrated against NASA's SMAP soil-moisture data.

How & where you'd use it. Supports drought tracking, flood and agriculture monitoring, and water-cycle research, especially in tropical and subtropical regions with frequent revisits.

What's measured

LAND SURFACE › SOILS › SOIL MOISTURE/WATER CONTENT

Coverage & cadence

  • Time span2018-08-01 → ongoing
  • Measured byCYGNSS (DDMI)
  • Processing levelLevel 3
  • Spatial extent-135, -38.15, 164, 38.15
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The CYGNSS Level 3 Soil Moisture V3.2 dataset is provided by the CYGNSS Science Team of the University of Michigan. It estimates volumetric water content for soils between 0-5 cm depth at a 6-hour discretization for most of the subtropics from the V3.2 reflectivity measurements provided in the CYGNSS L1 SDR dataset (https://doi.org/10.5067/CYGNS-L1X32). 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 Originally made up of a constellation of eight micro-satellites, the observatories provide nearly gap-free Earth coverage using an orbital inclination of approximately 35°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. The soil moisture retrieval algorithm is an update of the previous version developed by UCAR-CU using a linear regression of CYGNSS angle-normalized effective surface reflectivity trained against collocated SMAP soil moisture during the calibration period 8/1/2018 to 11/15/2023. The data are archived in daily files in netCDF-4 format. Volumetric soil moisture water content in units of cm3/cm3 is provided with two gridding resolutions, 9x9 km and 36x36 km. The variable SM_subdaily contains data reported in six hour intervals. The variable SM_daily provides a daily average. The time series covers the period from August 2018 to present.

Get the data

cygnss_l3_soil_moisture_v3.2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CYGNSS_L3_SOIL_MOISTURE_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.