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Description

This Level-3 (L3) product provides a daily composite of Northern Hemisphere landscape freeze/thaw conditions retrieved by the Soil Moisture Active Passive (SMAP) radar from 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. SMAP L-band backscatter data are used to derive freeze/thaw data, which are then resampled to an Earth-fixed, Northern Hemisphere azimuthal 3 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0).

Version Description

Changes to this version include:
  • Transitioned to Validated-Stage 2
  • Uses SPL1CS0 V3 Validated data as input
  • Using full swath except for nadir-anomaly flagged areas to provide better coverage
  • Resolved some flag and fillValue errors
For the full major and minor version history, go to https://nsidc.org/data/smap/version-history

Product Summary

Platforms
SMAP
Instruments
SMAP L-BAND RADAR
Spatial Extent

N: 85.044 S: 45 E: 180 W: -180

Spatial Resolution
3 Kilometers x 3 Kilometers
Spatial Reference System(s)
WGS 84 / NSIDC EASE-Grid 2.0 North (EPSG:6931)
Location
NORTHERN HEMISPHERE
Coordinate System
CARTESIAN
Granule Spatial Representation
CARTESIAN
Temporal Extent
2015-04-13 to 2015-07-07
Temporal Resolution
1 Day
Concept ID
C2872766057-NSIDC_CPRD
Data State
COMPLETE
Number of Files/Granules
84
Processing Level
3
Published
Science Keywords
Freeze/Thaw ,
SIGMA NAUGHT ,
Transition Direction

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

Dunbar, R., Xu, X., Colliander, A., Derksen, C., McDonald, K., Podest, E., Njoku, E., Kimball, J., & Kim, Y. (2016). SMAP L3 Radar Northern Hemisphere Daily 3 km EASE-Grid Freeze/Thaw State, Version 3 [Dataset]. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/CPSA0M496MGB Date Accessed: 2026-06-10

Documents

Publications Citing This Dataset

Filters
Title Year Author Topic
Satellite Microwave Remote Sensing of Landscape FreezeThaw Status Related to Frost Hazard Monitoring Kim, Youngwook, Kimball, John S., Du, Jinyang Plant Phenology, Normalized Difference Vegetation Index (NDVI), Plant Phenological Changes, Vegetation Index, Enhanced Vegetation Index (EVI), Freeze/Thaw, Transition Direction
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