SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Land Model Constants, Version 2 (SPL4SMLM)
Data set:
SPL4SMLM
There is a more recent version of these data.
Version Summary
Version Summary
Updated to coincide changes to SPL4SMAU V1 and SPL4SMGP V1.
Overview
SMAP Level-4 (L4) surface and root zone soil moisture data are provided in three products:
- SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Geophysical Data (SPL4SMGP)
- SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Analysis Update (SPL4SMAU)
- SMAP L4 9 km EASE-Grid Surface and Root Zone Soil Moisture Land Model Constants (SPL4SMLM)
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.
Data Contributor(s):
Reichle, R., G. De Lannoy, R. D. Koster, W. T. Crow, and J. S. Kimball.
Parameter(s):
SOIL CLASSIFICATION
SOIL DEPTH
SOIL POROSITY
SOIL TEXTURE
TERRAIN ELEVATION
Platform(s):
SMAP Observatory
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5, HDF5
Temporal Coverage:
31 March 2015 to present
Temporal Resolution:
3 hour
Spatial Resolution:
9 km
9 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
User Guide
ATBDs
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-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.
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 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.
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 contai
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.