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Full catalog/CYGNSS_L3_SOIL_MOISTURE_V1.0
CYGNSS_L3_SOIL_MOISTURE_V1.0·v1.0·dataset

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

UCAR-CU CYGNSS Level 3 Soil Moisture Version 1.0
land NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. Estimates of how wet the top few centimeters of soil are, given as the fraction of water in the soil, refreshed several times a day across most of the subtropics.

How it's made. Researchers measured how GPS signals reflect off the land using the CYGNSS satellites, then calibrated those reflections against soil-moisture readings from NASA's SMAP satellite to convert them into soil-wetness values.

How & where you'd use it. Handy for tracking drought, flooding risk, and how soil moisture shifts day to day in regions that other satellites struggle to cover frequently.

What's measured

LAND SURFACE › SOILS › SOIL MOISTURE/WATER CONTENT

Coverage & cadence

  • Time span2017-03-18 → ongoing
  • Measured byCYGNSS (DDMI)
  • Processing levelLevel 3
  • Spatial extent-135, -38, 164, 38
  • 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 Product provides volumetric water content estimates for soils between 0-5 cm depth at a 6-hour discretization for most of the subtropics. The data were produced by CYGNSS investigators at the University Corporation for Atmospheric Research (UCAR) and the University Colorado at Boulder (CU), and derive from version 2.1 of the CYGNSS L1 SDR. The soil moisture algorithm uses collocated soil moisture retrievals from SMAP to calibrate CYGNSS observations from the same day. For a given location, a linear relationship between the SMAP soil moisture and CYGNSS reflectivity is determined and used to transform the CYGNSS observations into soil moisture. The data are archived in daily files in netCDF-4 format. Two soil moisture variables report the volumetric water content in units of cm3/cm3. The variable SM_subdaily includes up to four soil moisture estimates per day. Another variable SM_daily provides a daily average. The time series covers the period from March 2017 to present.

Get the data

cygnss_l3_soil_moisture_v1.0_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CYGNSS_L3_SOIL_MOISTURE_V1.0",
    version="1.0",
    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.