SMAP L1A Radiometer Time-Ordered Parsed Telemetry, Version 2
Data set id:
DOI: 10.5067/JGV8EY3FGAH1
This is the most recent version of these data.
Version Summary

Changes to this version include:

  • Transitioned to Validated-Stage 2

  • Calibration parameters were adjusted to reduce calibration jumps and drift previously present in the Beta-release; as a result, calibration now meets its less than 0.4 K/month stability back to 31 March 2015

  • Additional bit-error checking was performed on Level-0 instrument telemetry

For the full major and minor version history, go to


Each Level-1A (L1A) granule incorporates all radiometer data downlinked from the Soil Moisture Active Passive (SMAP) spacecraft for one specific half orbit. The data are scaled instrument counts of the following:

  • The first four raw moments of the fullband channel for both vertical and horizontal polarizations
  • The complex cross-correlations of the fullband channel
  • The 16 subband channels for both vertical and horizontal polarizations
Data Format(s):
Temporal Coverage:
31 March 2015 to present
Temporal Resolution:
  • 49 minute
Spatial Resolution:
  • 40 km
  • 40 km
Spatial Coverage:
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

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Help Articles

General Questions & FAQs

SMAP Ancillary data sets are used to produce SMAP Level-1, -2, -3, and -4 standard data products.
The following table describes both the required and actual latencies for the different SMAP radiometer data sets. Latency is defined as the time (# days, hh:mm:ss) from data acquisition to product generation.

How to Articles

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