SMAP L3 Radar Northern Hemisphere Daily 3 km EASE-Grid Freeze/Thaw State, Version 3
Data set id:
SPL3FTA
DOI: 10.5067/CPSA0M496MGB
This is the most recent version of these data.
Version Summary
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

Overview

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).
Parameter(s):
FREEZE/THAWSIGMA NAUGHTTRANSITION DIRECTION
Platform(s):
SMAP
Sensor(s):
SMAP L-BAND RADAR
Data Format(s):
HDF5, HDF5
Temporal Coverage:
13 April 2015 to 7 July 2015
Temporal Resolution:
  • 1 day
Spatial Resolution:
  • 3 km
  • 3 km
Spatial Reference System(s):
WGS 84 / NSIDC EASE-Grid 2.0 North
EPSG:6931
Spatial Coverage:
N:
85.044
S:
45
E:
180
W:
-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

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Help Articles

General Questions & FAQs

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.
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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
Harmony API Quickstart Guide: Customizing NASA NSIDC DAAC data in Earthdata Cloud
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