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SMAP L2 Radar/Radiometer Half-Orbit 9 km EASE-Grid Soil Moisture, Version 3 (SPL2SMAP)
Data set:
SPL2SMAP
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This is the most recent version of these data.
Version Summary
Changes to this version include:
  • Transitioned to Validated-Stage 2

  • Uses SPL2SMA V3 Validated and SPL2SMP V3 Validated as input

  • Snapshot beta parameter estimation

  • Updated soil texture files (renormalized cases where sand+clay > 100%)

  • Updated default beta parameter



For the full major and minor version history, go to https://nsidc.org/data/smap/data_versions.

Overview

This Level-2 (L2) soil moisture product provides estimates of global land surface conditions retrieved by both the Soil Moisture Active Passive (SMAP) radar and radiometer during 6:00 a.m. descending half-orbit passes. SMAP L-band backscatter and brightness temperatures are used to derive soil moisture data, which are then resampled to an Earth-fixed, global, cylindrical 9 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0).
Data Contributor(s):
Entekhabi, D., N. Das, E. G. Njoku, J. T. Johnson, and J. Shi.
Parameter(s):
BRIGHTNESS TEMPERATURE SIGMA NAUGHT SOIL MOISTURE
Platform(s):
SMAP
Sensor(s):
SMAP L-BAND RADAR, SMAP L-BAND RADIOMETER
Data Format(s):
HDF5, HDF5
Temporal Coverage:
13 April 2015 to 7 July 2015
Temporal Resolution:
49 minute
Spatial Resolution:
9 km
9 km
Spatial Coverage:
N:
85.044
S:
-85.044
E:
180
W:
-180

Data Access & Tools

A free NASA Earthdata Login account is required to access these data. Learn More

Help Articles

How To

Many NSIDC data set web pages provide the ability to search and filter data with spatial and temporal contstraints using a map-based interface. This article outlines how to order NSIDC DAAC data using advanced searching and filtering. 
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.
The following are instructions on how to import and geolocate SMAP Level-1C HDF5 data in ENVI. Testing notes Software: ENVI Software version: 5.3 and above. If using version 5.3, service pack 5.3.1 is needed.  Platform: Windows 7
Data subscriptions are available for select NSIDC DAAC data collections (found below). Our subscription service automatically sends you new data as they are delivered from active NASA satellite missions.
  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).
NASA Earthdata Search is a map-based interface where a user can search for Earth science data, filter results based on spatial and temporal constraints, and order data with customizations including re-formatting, re-projecting, and spatial and parameter subsetting.

Getting started

SMAP Ancillary data sets are used to produce SMAP Level-1, -2, -3, and -4 standard data products.
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.