Near Real-time SMAP L1B Radiometer Half-Orbit Time-Ordered Brightness Temperatures, Version 105
Data set id:
SPL1BTB_NRT
DOI: 10.5067/UH70WUPQKCFR
This is the most recent version of these data.
Version Summary
Version Summary
Initial release
Overview
This Near Real-Time (NRT) data set corresponds to the standard SMAP L1B Radiometer Half-Orbit Time-Ordered Brightness Temperatures (SPL1BTB) product. The data provide calibrated estimates of time-ordered geolocated brightness temperature data measured by the Soil Moisture Active Passive (SMAP) passive microwave radiometer, the SMAP L-band radiometer. These Near Real-Time data are available within three hours of satellite observation. The data are created using the latest available ancillary data and spacecraft and antenna attitude data to reduce latency. The SMAP satellite orbits Earth every two to three days, providing half-orbit, ascending and descending, coverage from 86.4°S to 86.4°N in swaths 1000 km across. Data are stored for approximately two to three weeks. Thus, at any given time, users have access to at least fourteen consecutive days of Near Real-Time data through the NSIDC DAAC. Users deciding between the NRT and standard SMAP products should consider the immediacy of their needs versus the quality of the data required. Near real-time data are provided for operational needs whereas standard products meet the quality needs of scientific research. If latency is not a primary concern, users are encouraged to use the standard science product, SPL1BTB (https://doi.org/10.5067/ZHHBN1KQLI20).
Parameter(s):
ANTENNA TEMPERATURE
BRIGHTNESS TEMPERATURE
Platform(s):
SMAP
Sensor(s):
SMAP L-BAND RADIOMETER
Data Format(s):
HDF5
Temporal Coverage:
- 26 June 2025 to present
Temporal Resolution:
- 49 minute
Spatial Resolution:
- 47 km
- 36 km
Spatial Reference System(s):
- WGS 84EPSG:4326
Spatial Coverage:
- N:86.4S:-86.4E:180W:-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
Data Access & Tools
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Help Articles
General Questions & FAQs
This article covers frequently asked questions about the NASA NSIDC DAAC's Earthdata cloud migration project and what it means to data users.
When utilizing the SMAP Near-Real-Time (NRT) data products (SPL2SMP_NRT and SPL1BTB_NRT) it is important to understand how they differ from standard SMAP data
The NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) provides access to two SMAP LANCE Near Real Time data sets:
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.
The NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is migrating its primary data access from its legacy, on-premises archive to the NASA Earthdata Cloud.