SMAP L2 Radiometer Half-Orbit 36 km EASE-Grid Soil Moisture, Version 8
Data set id:
SPL2SMP
DOI: 10.5067/LPJ8F0TAK6E0
There is a more recent version of these data.
Version Summary
Version Summary
Changes to this version include:
- Dual Channel Algorithm (DCA) replaces Single Channel Algorithm – Vertical (SCA-V) as baseline algorithm
- Addition of two soil texture data elements, organic_content and sand_fraction. These represent the aggregated organic content and sand fraction within the 36 km grid cell, respectively.
- Bulk_density maximum value changed from 1.0 to 2.65.
- Dual Channel Algorithm (DCA) replaces Single Channel Algorithm – Vertical (SCA-V) as baseline algorithm
- Addition of two soil texture data elements, organic_content and sand_fraction. These represent the aggregated organic content and sand fraction within the 36 km grid cell, respectively.
- Bulk_density maximum value changed from 1.0 to 2.65.
Overview
This Level-2 (L2) soil moisture product provides estimates of global land surface conditions retrieved by the Soil Moisture Active Passive (SMAP) passive microwave radiometer during 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. SMAP L-band brightness temperatures are resampled to an Earth-fixed, global, cylindrical 36 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) [and made available as the SPL1CTB product], and the gridded brightness temperatures are then used to derive gridded soil moisture data.
Parameter(s):
BRIGHTNESS TEMPERATURESURFACE SOIL MOISTURE
Platform(s):
SMAP
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5
Temporal Coverage:
31 March 2015 to present
Temporal Resolution:
- 49 minute
Spatial Resolution:
- 36 km
- 36 km
Spatial Reference System(s):
WGS 84 / NSIDC EASE-Grid 2.0 Global
EPSG:6933
Spatial Coverage:
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.
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General Questions & FAQs
SMAP data files contain rich quality information that can be useful for many data users. The retrieval quality flag and surface flag bit values and interpretations are documented in the respective product Data Fields pages of the user guides for these data products
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
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
To convert HDF5 files into binary format you will need to use the h5dump utility, which is part of the HDF5 distribution available from the HDF Group. How you install HDF5 depends on your operating system.
The following are instructions on how to import and geolocate SMAP Level-1C HDF5 data in ENVI.
Testing notes
Software: ENVI
Software version: 5.3 and above. If using version 5.3, service pack 5.3.1 is needed.
Platform: Windows 7
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