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Full catalog/SPL2SMP_E
SPL2SMP_E·v006·dataset

How wet the soil is (SMAP, 9 km)

SMAP Enhanced L2 Radiometer Half-Orbit 9 km EASE-Grid Soil Moisture V006
land NASA NSIDC_CPRD Level 2 active HDF5
In plain English

What it measures. How wet the top layer of soil is, mapped at about 9-kilometer detail, along with the underlying microwave brightness temperature readings used to derive it.

How it's made. Derived from the SMAP satellite's microwave radiometer during its morning and evening passes, using a sharpening technique to squeeze maximum detail out of the raw signals before converting them to soil moisture.

How & where you'd use it. Supports drought and flood forecasting, agriculture and irrigation planning, and weather and climate prediction that depends on knowing how moist the land is.

What's measured

SPECTRAL/ENGINEERING › MICROWAVE › BRIGHTNESS TEMPERATURELAND SURFACE › SOILS › SOIL MOISTURE/WATER CONTENT › SURFACE SOIL MOISTURE

Coverage & cadence

  • Time span2015-03-31 → ongoing
  • Measured bySMAP (SMAP L-BAND RADIOMETER)
  • Processing levelLevel 2
  • Spatial extent-180, -85.044, 180, 90
  • FormatsHDF5
  • 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

This enhanced Level-2 (L2) product contains calibrated, geolocated, brightness temperatures acquired by the Soil Moisture Active Passive (SMAP) radiometer during 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. This product is derived from SMAP Level-1B (L1B) interpolated antenna temperatures. Backus-Gilbert optimal interpolation techniques are used to extract maximum information from SMAP antenna temperatures and convert them to brightness temperatures, which are posted to the 9 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) in a global cylindrical projection [available as the SPl1CTB_E product]. As of 2021, the data are also posted to the Northern Hemisphere EASE-Grid 2.0, an azimuthal equal-area projection. These 9-km brightness temperatures are then used to retrieve surface soil moisture posted on the 9-km grid [this SPL2SMP_E product].

Get the data

spl2smp_e_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SPL2SMP_E",
    version="006",
    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 NSIDC_CPRD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.