SMAP L3 Radiometer Global and Northern Hemisphere Daily 36 km EASE-Grid Freeze/Thaw State, Version 4
Data set id:
SPL3FTP
DOI: 10.5067/LQQ5I3QVGFTU
This is the most recent version of these data.
Version Summary
Version Summary
Changes to this version include:
• Minor bug fix to correct the indexing of bits in the AMSER-E never-frozen never-thawed maps
• An improved processing methodology was applied to the input Level-1C radiometer brightness temperatures.
• The data algorithms, structure, content, or processor code are otherwise unchanged from the previous version.
For the full major and minor version history, go to https://nsidc.org/data/smap/version-history
• Minor bug fix to correct the indexing of bits in the AMSER-E never-frozen never-thawed maps
• An improved processing methodology was applied to the input Level-1C radiometer brightness temperatures.
• The data algorithms, structure, content, or processor code are otherwise unchanged from the previous version.
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 landscape freeze/thaw conditions retrieved by the Soil Moisture Active Passive (SMAP) radiometer from 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. SMAP L-band brightness temperatures are used to derive freeze/thaw state and transition data, which are then resampled to both an Earth-fixed, Northern Hemisphere azimuthal 36 km Equal-Area Scalable Earth Grid (EASE-Grid 2.0), and to an Earth-fixed global 36 km EASE-Grid 2.0.
Parameter(s):
TRANSITION DIRECTION
Platform(s):
SMAP
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5
Temporal Coverage:
31 March 2015 to present
Temporal Resolution:
- 1 day
Spatial Resolution:
- 36 km
- 36 km
Spatial Reference System(s):
WGS 84 / NSIDC EASE-Grid 2.0 North
EPSG:6931
WGS 84 / NSIDC EASE-Grid 2.0 Global
EPSG:6933
Spatial Coverage:
N:
85.044
S:
45
E:
180
W:
-180
N:
85.044
S:
-85.044
E:
180
W:
-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
Data Access & Tools
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Documentation
User Guide
Quality Assessment Reports
Product Specification Documents
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.
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.
This short article describes the customization services available for SMAP data using Earthdata Search.
How to Articles
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Data subscriptions are available for select NSIDC DAAC data collections. Once signed up, the subscription service automatically sends you new data as they are delivered from active NASA satellite missions.
All data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is directly accessible through our HTTPS file system using Wget or curl. This article provides basic command line instructions for accessing data using this method.
This article highlights the NSIDC DAAC data sets available with customization options and outlines a workflow for searching, ordering, and customizing data in NASA Earthdata Search. This approach is ideal for users who want to download data to their local machine.
NASA Worldview is a map interface that allows users to interactively browse imagery, create visualizations, and download the underlying data.
NASA's Global Imagery Browse Services (GIBS) provides up to date, full resolution imagery for selected NSIDC DAAC data sets.