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SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil Moisture, Version 2 (SPL3SMP)
Data set:
SPL3SMP
Citation
There is a more recent version of these data.
Version Summary

Changes to this version include:



  • Uses updated SPL1CTB and SPL2SMP V2 Beta data as input

  • Corrects the retrieval quality flag error

Overview

This Level-3 (L3) soil moisture product provides a composite of daily estimates of global land surface conditions retrieved by the Soil Moisture Active Passive (SMAP) passive microwave radiometer. Ancillary data include soil temperature, vegetation water content, and vegetation opacity and albedo. Input SMAP L-band brightness temperatures are resampled to a global, cylindrical 36 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0). Note: These data are beta release quality, meaning that they have not undergone full validation and may still contain significant errors. In addition, the data field that indicates retrieval quality, called retrieval qual flag, was found to contain incorrect information. Users are advised to ignore this data field 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):
BRIGHTNESS TEMPERATURE SOIL MOISTURE
Platform(s):
SMAP Observatory
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5, HDF5
Temporal Coverage:
31 March 2015 to 20 April 2016
Temporal Resolution:
1 day
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.

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.
This step-by-step tutorial demonstrates how to access MODIS and SMAP data using the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS). AppEEARS allows users to access, explore, and download point and area data with spatial, temporal, and parameter subsets.
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
This How to guide outlines the steps for properly importing, projecting and visualizing HDF and NetCDF files in ArcMap. A couple of things to note before you start:
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

OPeNDAP, the Open-source Project for a Network Data Access Protocol, is a NASA community standard DAP that provides a simple way for researchers to access and work with data over the internet.
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.