SMAP L4 Global Daily 9 km EASE-Grid Carbon Net Ecosystem Exchange, Version 5 (SPL4CMDL)
Data set:
There is a more recent version of these data.
Version Summary
Changes to this version primarily represent changes to the model inputs and model Biome Properties Look-up Table (BPLUT) calibration rather than changes to the internal model structure or code. The Version 5 product accuracy and performance is largely consistent with Version 4. Specific changes include:
- Revised Level-4 carbon global model calibration and soil organic carbon (SOC) initialization using the latest SMAP Nature Run (NRv8.3) soil moisture and soil temperature data, and MERRA-2 surface meteorology.
- The carbon model BPLUT has been recalibrated using a FLUXNET2015 global tower site record that includes 329 sites representing all major global plant functional type (PFT) classes.
- Implemented minor changes to spatial weighting of FLUXNET2015 tower sites in the Level-4 carbon model BPLUT calibration. Northern (≥ 45°N) tower sites now have greater impact in defining global PFT response characteristics; whereby, the adjusted weighting is designed to enhance product performance in boreal-arctic biomes. It also incorporated a more detailed set of PFT realistic range constraints for the BPLUT parameters prior to the model calibration and optimization.
- Enhanced an attribute in the legend_carbon_model_bitflag data field to include descriptions of the bit values.

For the full major and minor version history, go to


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.
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:

Data Access & Tools

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

Help Articles

How To

Many NSIDC DAAC data sets can be accessed using the NSIDC DAAC's Data Access Tool. This tool provides the ability to search and filter data with spatial and temporal constraints using a map-based interface. Users have the option to
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All 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, using wget or curl. Basic command line instructions are provided in the article below. 
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.
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NASA's Global Imagery Browse Services (GIBS) provides up to date, full resolution imagery for selected NSIDC DAAC data sets. 

Getting started

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