Name: SMAP L2 Radiometer Half-Orbit 36 km EASE-Grid Soil Moisture, Version 8
Creator: National Snow and Ice Data Center
Keywords: BRIGHTNESS TEMPERATURE,SURFACE SOIL MOISTURE

SMAP L2 Radiometer Half-Orbit 36 km EASE-Grid Soil Moisture, Version 8

Data set id:

SPL2SMP

DOI: 10.5067/LPJ8F0TAK6E0

Data Citation and Acknowledgment
As a condition of using these data, you must cite the use of this data set. Such a practice gives credit to data set producers and advances principles of transparency and reproducibility.

O'Neill, P. E., Chan, S., Njoku, E. G., Jackson, T., Bindlish, R. & Chaubell, J. (2021). SMAP L2 Radiometer Half-Orbit 36 km EASE-Grid Soil Moisture. (SPL2SMP, Version 8). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/LPJ8F0TAK6E0. [describe subset used if applicable]. Date Accessed 11-15-2026.

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Literature references: Please include the following literature citations in addition to the data citation above:

Chan, S., Bindlish, R., O'Neill, P. E., Njoku, E. G., Jackson, T., Colliander, A., Chen, F., Burgin, M., Dunbar, S., Piepmeier, J. R., Yueh, S., Entekhabi, D., Cosh, M., Caldwell, T., Walker, J., Berg, A., Rowlandson, T., Pacheco, A., McNairn, H., Thibeault, M., Martinez-Fernandez, J., González-Zamora, A., Bosch, D., Starks, P., Goodrich, D., Prueger, J., Palecki, M., Small, E. E., Zreda, M., Calvet, J., Crow, W. T. & Kerr, Y.. 2016. Assessment of the SMAP passive soil moisture product. IEEE Transactions on Geoscience and Remote Sensing. 54. DOI: 10.1109/TGRS.2016.2561938.

There is a more recent version of these data.
Version Summary

Changes to this version include:
- Dual Channel Algorithm (DCA) replaces Single Channel Algorithm – Vertical (SCA-V) as baseline algorithm
- Addition of two soil texture data elements, organic_content and sand_fraction. These represent the aggregated organic content and sand fraction within the 36 km grid cell, respectively.
- Bulk_density maximum value changed from 1.0 to 2.65.

Overview

This Level-2 (L2) soil moisture product provides estimates of global land surface conditions retrieved by the Soil Moisture Active Passive (SMAP) passive microwave radiometer during 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. SMAP L-band brightness temperatures are resampled to an Earth-fixed, global, cylindrical 36 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) [and made available as the SPL1CTB product], and the gridded brightness temperatures are then used to derive gridded soil moisture data.

Parameter(s):

BRIGHTNESS TEMPERATURE

SURFACE SOIL MOISTURE

Platform(s):

SMAP

Sensor(s):

SMAP L-BAND RADIOMETER

Data Format(s):

HDF5

Temporal Coverage:

31 March 2015 to 4 December 2023

Temporal Resolution:

49 minute

Spatial Resolution:

36 km

36 km

Spatial Reference System(s):

WGS 84 / NSIDC EASE-Grid 2.0 Global
EPSG:6933

Spatial Coverage:

Northern latitude
85.044
Southern latitude
-85.044
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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This data set has been retired. There is a more recent version of these data.

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