# SMAP L3 Daily Global Composite Soil Moisture
*data products*

## Specifications
- **level**: L3
- **distributor**: nasa-jpl
- **gsd m**: {"native":36000}
- **access endpoint**: https://nsidc.org/data/smap/data
- **access model**: open
- **licence**: NASA open data
- **cost model summary**: Free and open via NSIDC and ASF; daily global passive L-band radiometer composite
- **primary data portal url**: https://smap.jpl.nasa.gov/data/
- **deployment context**: orbital
- **entity type**: data_product
- **last verified date**: 2026-05-31
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **provider**: nasa-jpl
- **attributes**: {"level":"L3","distributor":"nasa-jpl","gsd_m":"{\"native\":36000}","access_endpoint":"https://nsidc.org/data/smap/data","access_model":"open","licence":"NASA open data","cost_model_summary":"Free and open via NSIDC and ASF; daily global passive L-band radiometer composite","primary_data_portal_url":"https://smap.jpl.nasa.gov/data/","deployment_context":"orbital"}

## Editorial
SMAP L3 Daily Global Composite Soil Moisture (SPL3SMP) is a Level-3 product derived from the SMAP mission's passive L-band (1.41 GHz) radiometer. It provides daily global volumetric soil moisture composites on a 36 km EASE-Grid 2.0 projection.[^nsidc-smap-l3]

Each daily file is produced by compositing SPL2SMP half-orbit swaths for a single UTC day. Global spatial coverage extends from 85.044 N to 85.044 S. Freeze/thaw state products are limited to boreal regions above 45 degrees North. An enhanced spatial resolution version (SPL3SMP_E) at 9 km is available as a companion product.[^nsidc-smap-l3]

Files are distributed in HDF5 format. The current dataset version is v009. The archive begins approximately in April 2015, following the end of the mission commissioning phase.[^smap-jpl-data]

Distribution is via the NSIDC DAAC. Access is free under the NASA open data policy.[^nsidc-smap-l3]

## Compositional position
- soil-moisture (topics) --[topic_capabilities]--> SMAP L3 Daily Global Composite Soil Moisture
- groundwater (topics) --[topic_capabilities]--> SMAP L3 Daily Global Composite Soil Moisture

## Sources
- [nsidc-smap-l3] | SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil Moisture, Version 9, NSIDC | https://nsidc.org/data/spl3smp/versions/9 | tier=agency-doc | accessed=2026-05-31
- [smap-jpl-data] | SMAP data overview, NASA JPL | https://smap.jpl.nasa.gov/data/ | tier=operator-datasheet | accessed=2026-05-31

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Source: https://eo-atlas.org/data_products/smap-l3-soil-moisture
Maintainer: SpectraWorks B.V. (CC-BY 4.0)