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SMAP L4 Global Daily 9 km EASE-Grid Carbon Net Ecosystem Exchange, Version 6 (SPL4CMDL)
Data set:
This is the most recent version of these data.
Version Summary
Changes to this version primarily reflect BPLUT recalibration and SOC re-initialization in response to updates to the upstream input datasets. Specifically:
• Revised SPL4CMDL global BPLUT calibration and SOC initialization using the latest SMAP Nature Run (NRv9.1) soil moisture and soil temperature data, and MERRA-2 surface meteorology.
• The carbon model BPLUT, Vv6040, has been recalibrated using the most recent FLUXNET2015 global tower site synthesis record, which includes 356 sites representing all major global plant functional type (PFT) classes.
• Adjusted model SOC decay parameters based on comparison with other global assessments, which reduced SOC storage estimates in the tropics (20 S – 20 N) from the previous (V5) SPL4CMDL product release.


The Level-4 (L4) carbon product (SPL4CMDL) provides global gridded daily estimates of net ecosystem carbon (CO2) exchange derived using a satellite data based terrestrial carbon flux model informed by the following: Soil Moisture Active Passive (SMAP) L-band microwave observations, land cover and vegetation inputs from the Moderate Resolution Imaging Spectroradiometer (MODIS), Visible Infrared Imaging Radiometer Suite (VIIRS), and the Goddard Earth Observing System Model, Version 5 (GEOS-5) land model assimilation system. Parameters are computed using an Earth-fixed, global cylindrical 9 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) projection.
Data Contributor(s):
Kimball, J. S., L. A. Jones, A. Endsley, T. Kundig, and R. Reichle.
Aqua, GEOS-5, L4_C, SMAP, Suomi-NPP, Terra
Data Format(s):
Temporal Coverage:
31 March 2015 to present
Temporal Resolution:
1 day
Spatial Resolution:
9 km
9 km
Spatial Coverage:

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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 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.