Data Set ID: 
SPL4SMLM

SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Land Model Constants, Version 2

SMAP Level-4 (L4) surface and root zone soil moisture data are provided in three products:

For each product, SMAP L-band brightness temperature data from descending and ascending half-orbit satellite passes (approximately 6:00 a.m. and 6:00 p.m. local solar time, respectively) are assimilated into a land surface model that is gridded using an Earth-fixed, global, cylindrical 9 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) projection.

There is a more recent version of these data.

Version Summary: 

Updated to coincide changes to SPL4SMAU V1 and SPL4SMGP V1.

Parameter(s):
  • Soils > Soil Classification > SOIL CLASSIFICATION
  • Soils > Soil Depth > SOIL DEPTH
  • Soils > Soil Porosity > SOIL POROSITY
  • Soils > Soil Texture > SOIL TEXTURE
  • Topography > Terrain Elevation > TERRAIN ELEVATION
Data Format(s):
  • HDF5
Spatial Coverage:
N: 85.044, 
S: -85.044, 
E: 180, 
W: -180
Platform(s):SMAP Observatory
Spatial Resolution:
  • 9 km x 9 km
Sensor(s):SMAP L-BAND RADIOMETER
Temporal Coverage:
  • 31 March 2015
Version(s):V2
Temporal Resolution3 hourMetadata XML:View Metadata Record
Data Contributor(s):Reichle, R., G. De Lannoy, R. D. Koster, W. T. Crow, and J. S. Kimball.

Geographic Coverage

No access options.

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Reichle, R., G. De Lannoy, R. D. Koster, W. T. Crow, and J. S. Kimball. 2016. SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Land Model Constants, Version 2. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: https://doi.org/10.5067/VBRUC1AFRQ22. [Date Accessed].

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How To

Programmatic Data Access Guide
Data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) can be accessed directly from our HTTPS file system or through our Application Programming Interface (API). Our API offers you the ability to order data using specific temporal and spatial filters... read more
How to import and geolocate SMAP Level-3 and Level-4 data in ENVI
The following are instructions on how to import and geolocate SMAP Level-3 Radiometer Soil Moisture HDF5 data in ENVI. Testing notes Software: ENVI Software version: 5.3 Platform: Windows 7 Data set: SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil... read more
How do I access data using OPeNDAP?
Data can be programmatically accessed using NSIDC’s OPeNDAP Hyrax server, allowing you to reformat and subset data based on parameter and array index. For more information on OPeNDAP, including supported data sets and known issues, please see our OPeNDAP documentation: ... read more
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Filter and order from a data set web page
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How do I convert an HDF5/HDF-EOS5 file into binary format?
To convert HDF5 files into binary format you will need to use the h5dump utility, which is part of the HDF5 distribution available from the HDF Group. How you install HDF5 depends on your operating system. Full instructions for installing and using h5dump on Mac/Unix and... read more
NSIDC DAAC Data Subscription Requests
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FAQ

Why does the root zone soil moisture in the SMAP Level-4 soil moisture products vary in such close unison with the surface soil moisture?
The surface and root zone soil moisture estimates in the SMAP Level-4 soil moisture products are the outputs of a land surface model into which SMAP observations of brightness temperature have been assimilated. The coupling between the surface layer and the root zone layer is known to be very... read more
What are the latencies for SMAP radiometer data sets?
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. Short name Title Latency Required Actual (mean1) SPL1AP SMAP L1A... read more
Why do the soil moisture values in the SMAP Level-4 data vary from what I expect in a particular region?
There are a few reasons that the soil moisture data values in SMAP Level-4 data products may vary from what you expect in a particular region. The first step a data user should take in investigating apparently anomalous values is to look at the rich quality information and other data flags... read more
What data subsetting, reformatting, and reprojection services are available for SMAP data?
The following table describes the data subsetting, reformatting, and reprojection services that are currently available for SMAP data via the NASA Earthdata Search, a Data Subscription, and Programmatic Access. Short name Title Subsetting Reformatting... read more