SMAP/SMOS L3 Radiometer 9 km EASE-Grid Soil Moisture, Version 2
Data set id:
NSIDC-0800
DOI: 10.5067/T94XZ6D4SFBF
This is the most recent version of these data.
Version Summary
Changes to this version include algorithm updates and the addition of the following new
fields: albedo, surface_temperature, ndvi_vegetation_opacity, clay_fraction, and roughness_coefficient.

Overview

The Soil Moisture Active Passive (SMAP, launched in 2015) and the Soil Moisture and Ocean Salinity (SMOS, launched in 2009) missions are each L-band satellites that provide brightness temperature and soil moisture estimates and vegetation optical depth approximately every 2-3 days with a spatial resolution of ~40 km. By integrating brightness temperature observations from both satellites, these data products reduce the revisit time to about one day, improving the ability to monitor fast-response processes such as groundwater drainage and recharge, early dry-down after storms, and pre-storm soil moisture conditions for runoff determination. The Integrated SMAP and SMOS Soil Moisture Data is available in two products. The SMOS-Based SMAP L2 Radiometer Half-Orbit 9 km EASE-Grid Soil Moisture (NSIDC-0799) product is generated by processing half-orbit granules (either 6 AM ascending or 6 PM descending) from the pre-processed SMOS product. The L2 product consists solely of SMOS-based data, incorporating information after SMOS brightness temperatures (TBs) at a 40° incidence angle were inter-calibrated and the soil moisture (SM) and vegetation optical depth (VOD) were retrieved using the SMAP Dual Channel Algorithm (DCA). The SMAP/SMOS L3 Radiometer 9 km EASE-Grid Soil Moisture (NSIDC-0800) product is generated by the processing software ingesting one day’s worth of granules from both the SMAP SPL2SMP_E product and the SMOS-derived L2 data. The L3 product contains both SMAP and SMOS descending (6:00 AM/PM) and ascending (6:00 PM/AM) data stored in separate arrays.
Parameter(s):
BRIGHTNESS TEMPERATURE
SURFACE SOIL MOISTURE
VEGETATION OPTICAL DEPTH
Platform(s):
SMAP
SMOS
Sensor(s):
SMAP L-BAND RADIOMETER
SMOS L-BAND RADIOMETER
Data Format(s):
HDF5
Temporal Coverage:
  • 31 March 2015 to 30 June 2026
Temporal Resolution:
  • 1 day
Spatial Resolution:
  • 9 km
  • 9 km
Spatial Reference System(s):
  • WGS 84 / NSIDC EASE-Grid 2.0 Global
    EPSG:6933
Spatial Coverage:
  • Northern latitude
    90
    Southern latitude
    -90
    Eastern longitude
    180
    Western longitude
    -180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

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