• Welcome to the new nsidc.org! Please note that we are in a beta launch of this website. During the beta phase, our website search may act unpredictably until the website stabilizes.

SMAP L2 Radiometer Half-Orbit 36 km EASE-Grid Soil Moisture, Version 1 (SPL2SMP)
Data set:
SPL2SMP
Citation
There is a more recent version of these data.
Version Summary
First public data release

Overview

This Level-2 (L2) soil moisture product provides gridded 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. Input SMAP L-band brightness temperature data used to derive soil moisture are resampled to an Earth-fixed, global, cylindrical 36 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0). A variety of ancillary data are also used as input, such as soil texture and vegetation opacity. Note: These data are Beta-release quality, meaning that they have not undergone full validation and may still contain significant errors. Currently, in this Beta release, 6:00 p.m. ascending half-orbit granules are not considered by the SPL2SMP processing software; however, that inclusion is expected after further analysis. In addition, the data fields that indicate retrieval quality, called retrieval qual flag and retrieval qual flag option[1-5], were found to contain incorrect information. Users are advised to ignore these data fields in Version 1 of this product.
Data Contributor(s):
O'Neill, P. E., S. Chan, E. G. Njoku, T. Jackson, and R. Bindlish.
Parameter(s):
ALBEDO BRIGHTNESS TEMPERATURE SOIL MOISTURE/WATER CONTENT SURFACE ROUGHNESS VEGETATION WATER CONTENT
Platform(s):
SMAP Observatory
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5
Temporal Coverage:
9 September 2015 to 25 October 2015
Temporal Resolution:
49 minute
Spatial Resolution:
36 km
36 km
Spatial Coverage:
N:
85.044
S:
-85.044
E:
180
W:
-180

Data Access & Tools

This data set has been retired. There is a more recent version of these data.

Documentation

General Resources

Quality Assessment Reports

Product Specification Documents

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.
NASA Worldview uses the Global Imagery Browse Service (GIBS) to provide up to date, full resolution imagery for select NSIDC DAAC data sets (see attachments below).
NASA's Global Imagery Browse Services (GIBS) provides up to date, full resolution imagery for selected NSIDC DAAC data sets. 

Getting started

SMAP data files contain rich quality information that can be useful for many data users. The retrieval quality flag and surface flag bit values and interpretations are documented in the respective product Data Fields pages: Level-2 soil moisture product (SPL2SMP)
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.
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.