2026-08-19T16:51:14Zhttp://nsidc.org/api/dataset/metadata/oaioai:nsidc.org/SPL1BTB.0062026-06-24T19:16:46Zcumulusnasa_nsidc_daac
SPL1BTB.006SMAP L1B Radiometer Half-Orbit Time-Ordered Brightness TemperaturesPiepmeier, J. R., Mohammed, P., Peng, J., Kim, E. J., De Amici, G., Chaubell, J. & Ruf, C.SMAP L1B Radiometer Half-Orbit Time-Ordered Brightness Temperatures2023-12-04Boulder, Colorado USANASA NSIDC DAAC: NASA National Snow and Ice Data Center Distributed Active Archive Center6false10.5067/GWYQTF307Y9Yhttps://nsidc.org/sites/default/files/documents/user-guide/spl1btb-v006-userguide_0.pdfSPL1BTBTechnical ContactNSIDCUser Servicesnsidc@nsidc.org1-303-492-61991-303-492-2468CIRES, 449 UCBUniversity of ColoradoBoulderCO80309-0449USAEARTH SCIENCESPECTRAL/ENGINEERINGMICROWAVEBRIGHTNESS TEMPERATURE Climatology/Meteorology/AtmosphereGeoscientific InformationEASE-Grid SM-projectL1SMAP-projectSMAP-project-L1SMAP L-BAND RADIOMETERSMAP L-Band RadiometerSMAPSoil Moisture Active and Passive Observatory2015-03-31active-86.486.4-180180GEOGRAPHIC REGIONGLOBAL47 km36 km49 minuteSMAP data sets provide multiple means to assess quality. Each data set contains bit flags, uncertainty measures, and file-level metadata that provide quality information. The Data Fields and Metadata Fields documents describe the specific bit flags, uncertainty measures, and file-level metadata contained in this data set.
Each SMAP HDF5 data file contains metadata with Quality Assessment (QA) metadata flags. These QA metadata flags are calculated and set by the SDS at JPL prior to delivery to the National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC). A separate, ISO 19115-compliant metadata file with an .xml file extension is also delivered to NSIDC DAAC with the HDF5 data file; it contains the same information as the file-level metadata.
A separate QA file with a .qa file extension is also associated with each data file. QA files are ASCII text files that contain statistical information in order to help users better assess the quality of the associated data file.
In addition, various levels of QA are conducted with Level-1B data. If a file passes QA, the SDS applies that file for higher-level processing, browse generation, active science QA, and data archive and distribution. If a product fails QA, it is never delivered to NSIDC DAAC.These data are freely, openly, and fully accessible, provided that you are logged into your NASA Earthdata profile (https://urs.earthdata.nasa.gov/).These data are freely, openly, and fully available to use without restrictions, provided that you cite the data according to the recommended citation at https://nsidc.org/about/use_copyright.html. For more information on the NASA EOSDIS Data Use Policy, see https://earthdata.nasa.gov/earth-observation-data/data-use-policy.EnglishNASA/JPL/SMAPNASA NSIDC DAACNASA National Snow and Ice Data Center Distributed Active Archive Centerhttps://nsidc.org/daacData Center ContactNSIDCUser Servicesnsidc@nsidc.org1-303-492-6199National Snow and Ice Data CenterCIRES, 449 UCBUniversity of ColoradoBoulderCO80309-0449USAHTTPS1.4 GBHDF5Bringer, A., J. T. Johnson, P. N. Mohammed, J. R. Piepmeier, 2017. Performance of SMAP radiometer RFI detection algorithms and analysis of residual RFI sources. In Geoscience and Remote Sensing Symposium (IGARSS), 2017 IEEE International, 1243-1246.
Piepmeier, J. R. et al. 2018. SMAP Algorithm Theoretical Basis Document: L1B Radiometer Product: Includes L1A and L1B, Rev. C. SMAP Project, NASA GSFC SMAP-006, NASA Goddard Space Flight Center, Greenbelt, MD. (PDF, 1.95 MB; see Technical References).
Piepmeier, J., G. De Amici, P. Mohammed, and J. Peng. 2017. Improved Calibration through SMAP RFI Change Detection.
Piepmeier, J. R. et al. 2016. SMAP Algorithm Theoretical Basis Document: L1B Radiometer Product: Includes L1A and L1B. SMAP Project, NASA GSFC SMAP-006, NASA Goddard Space Flight Center, Greenbelt, MD. (PDF, 1.94 MB; see Technical References).
Piepmeier, J. R. , J. T. Johnson, P. N. Mohammed, D. Bradley, C. Ruf, M. Aksoy, R. Garcia, D. Hudson, L. Miles, and M. Wong. 2014. Radio-Frequency Interference Mitigation for the Soil Moisture Active Passive Microwave Radiometer. IEEE Transactions on Geoscience and Remote Sensing. 52(1):761-775. doi: https://dx.doi.org/10.1109/TGRS.2013.2281266.
Piepmeier, J. R., D. G. Long, and E. G. Njoku. 2008. Stokes Antenna Temperatures. IEEE Trans. Geosci. Remote Sens. 46(2):516-527.This Level-1B (L1B) product provides calibrated estimates of time-ordered geolocated brightness temperatures measured by the Soil Moisture Active Passive (SMAP) passive microwave radiometer. SMAP L-band brightness temperatures are referenced to the Earth's surface with undesired and erroneous radiometric sources removed.VIEW RELATED INFORMATIONhttps://nsidc.org/sites/default/files/documents/user-guide/spl1btb-v006-userguide_0.pdfSMAP L1B Radiometer Half-Orbit Time-Ordered Brightness Temperatures, Version 6 User GuideGET DATAhttps://search.earthdata.nasa.gov/search/granules?p=C2938661904-NSIDC_CPRDEarthdata SearchGET RELATED VISUALIZATIONhttps://worldview.earthdata.nasa.gov/?v=-186,-77,170,87&l=SMAP_L1_Passive_Faraday_Rotation_Fore,SMAP_L1_Passive_Faraday_Rotation_Aft,Coastlines_15m,MODIS_Terra_CorrectedReflectance_TrueColorWorldviewGET DATAhttps://cmr.earthdata.nasa.gov/virtual-directory/collections/C2938661904-NSIDC_CPRDHTTPSGET DATAhttps://nsidc.org/data/data-access-tool/SPL1BTB/versions/6/Data Access ToolGET DATAhttps://earthaccess.readthedocs.io/en/stable/earthaccessCEOS IDN DIFVERSION 9.92023-12-042026-06-24NSIDCVersion SummaryChanges to this version include:
• A new 1-km land-water mask based on the MODIS44w V6 data is used to determine land-water Tb corrections. The mask:
o more accurately portrays current coastal and inland water body boundaries
o adds an ice shelf type to determine an ice shelf fraction for a given footprint or grid cell, reflected in new data elements ice_shelf_fraction_h and ice_shelf_fraction_v
• The maximum Tb threshold has been reduced from 340K to 310K to further remove RFI contamination
For the full major and minor version history, go to <a href="https://nsidc.org/data/smap/version-history">https://nsidc.org/data/smap/version-history</a>NSIDCMinor VersionR17000Changed with version 5 update. See Major Version Summary.2015-03-312021-04-291R17030Version changes include:
- Antenna Scan Angle (ASA) correction: new code examines the initial scan angle in each scan and flags any scan angle that falls out of the normal range as bad
- No change to product format, quality, or size2021-04-2917NSIDCCurrent Version1NSIDCSpatial Reference SystemsEPSG:4326WGS 84NSIDCLevel of ServiceComprehensiveNSIDCFull Dataset CitationPiepmeier, J. R., Mohammed, P., Peng, J., Kim, E. J., De Amici, G., Chaubell, J. & Ruf, C. (2023). <i>SMAP L1B Radiometer Half-Orbit Time-Ordered Brightness Temperatures</i>. (SPL1BTB, Version 6). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. <a href="https://doi.org/10.5067/GWYQTF307Y9Y">https://doi.org/10.5067/GWYQTF307Y9Y</a>. [<i><describe subset used if applicable></i>].NSIDCRetiredfalseNSIDCRelated Servicesapplication/vnd.nasa.cmr.umm+jsonfalsebookerlmmt_service_52052S3107386427-NSIDC_CPRDNSIDC_CPRD3service2024-12-03T17:04:33.698Zhttps://cmr.earthdata.nasa.gov/virtual-directory/collections/NSIDC_CPRD_HTTPS_File_SystemNOT PROVIDED1HTTPS File SystemQuickly download a few files using a web browser, or access data through a command-line utility such as WGET.https://nsidc.org/data/user-resources/help-center/nasa-earthdata-cloud-data-access-guide#anchor-download-to-a-local-computer-from-earthdata-cloudVIEW RELATED INFORMATIONNASA Earthdata Cloud Data Access GuidePublicationURLUSER SERVICESNSIDC DAAC User ServicesEmailnsidc@nsidc.orgDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESSee https://github.com/nasa/Common-Metadata-Repository/releases for more information on the latest version.DEVELOPERMaintenance and Development, Earth Observing System Data and Information System, Earth Observing System,Goddard Space Flight Center, NASANASA/GSFC/EOS/EOSDIS/EMDORIGINATORPUBLISHERSERVICE PROVIDERNASA National Snow and Ice Data Center Distributed Active Archive CenterNASA NSIDC DAACNSIDC DAAC home pagehttps://nsidc.org/daacNASA Distributed Active Archive Center (DAAC) at NSIDC home page.https://cdn.earthdata.nasa.gov/umm/service/v1.4UMM-S1.4https://cmr.earthdata.nasa.gov/virtual-directory/collections/C2938661904-NSIDC_CPRDapplication/vnd.nasa.cmr.umm+jsonfalseamy.steikermmt_service_25004S2472217299-NSIDC_CPRDNSIDC_CPRD1service2022-09-20T22:05:06.185Zs3://nsidc-cumulus-prod-protected/NSIDC_CPRD_S3NOT PROVIDED1.0NASA Earthdata Cloud (AWS S3)Access data directly from the NASA Earthdata Cloud via Amazon Web Services Simple Storage Service (AWS S3). This access option is only available when working within the us-west-2 region and requires additional AWS S3 credentials.https://nsidc.org/data/user-resources/help-center/nasa-earthdata-cloud-data-access-guideVIEW RELATED INFORMATIONNASA Earthdata Cloud Data Access GuidePublicationURLhttps://data.nsidc.earthdatacloud.nasa.gov/s3credentialsVIEW RELATED INFORMATIONAWS S3 CredentialsPublicationURLUSER SERVICESNSIDC DAAC User ServicesEmailnsidc@nsidc.orgDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESThis is the most current release of this service. Last updated date is unknown.SERVICE PROVIDERNASA National Snow and Ice Data Center Distributed Active Archive CenterNASA NSIDC DAAChttps://cdn.earthdata.nasa.gov/umm/service/v1.4UMM-S1.4https://nsidc.org/data/user-resources/help-center/nasa-earthdata-cloud-data-access-guideNSIDCRelated Toolsapplication/vnd.nasa.cmr.umm+jsonfalsefritzdimmt_tool_50907TL3010466318-NSIDC_CPRDNSIDC_CPRD5tool2026-06-24T18:30:53.034Zhttps://zenodo.org/badge/latestdoi/399867529DOWNLOAD SOFTWAREhttps://earthaccess.readthedocs.io/en/stable/DistributionURLNSIDC_CPRD_EARTHACCESSDownloadable Tool0.18.0earthaccessearthaccess is a python library to search and access NASA Earth science data with just a few lines of code.https://github.com/earthaccess-dev/earthaccessVIEW RELATED INFORMATIONGitHub RepositoryPublicationURLDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA SEARCHDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESPUBLISHERNSIDC DAAC User ServicesEmailnsidc@nsidc.orgPUBLISHERNASA National Snow and Ice Data Center Distributed Active Archive Centerhttps://nsidc.org/daac/NASA NSIDC DAACPUBLISHERNational Snow and Ice Data Centerhttp://nsidc.orgNSIDCDEVELOPERAlaska Satellite Facilityhttps://www.asf.alaska.edu/ASFDEVELOPERInstitute for the Study of Earth, Oceans, and Space, University of New Hampshirehttp://www.eos.unh.edu/UNH/EOSDEVELOPERAtmospheric Science Data Center, Science Directorate, Langley Research Center, NASAhttps://asdc.larc.nasa.gov/NASA/LARC/SD/ASDCMIT License
Copyright (c) 2021 Luis Lopez
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.2026-05-12T00:00:00.000ZAs a condition of use, we request that you properly cite the earthaccess library to acknowledge the creators. Formal citations also make it easier for us to track the use and impact of our data and tools, and helps us report data distribution activity and tool usage metrics to funding agencies.
If you have used earthaccess in your research, please cite as:
Barrett, A., Battisto, C., Bourbeau, J., Fisher, M., Kaufman, D., Kennedy, J., Lopez, L., Lowndes, J., Scheick, J., & Steiker, A. (2024). earthaccess (Version 0.9.0) [Computer software]. https://doi.org/10.5281/zenodo.8365009
See https://github.com/nsidc/earthaccess/releases for more information on the latest version.https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0Python3.8 or higherhttps://earthaccess.readthedocs.io/en/stable/application/vnd.nasa.cmr.umm+jsonfalsecrumlydmmt_tool_12314TL4019511337-NSIDC_CPRDNSIDC_CPRD1tool2026-02-11T17:42:34.275ZGOTO WEB TOOLhttps://nsidc.org/data/data-access-tool/DistributionURLNSIDC_CPRD_Data_Access_ToolWeb User Interface3.1.0Data Access ToolFilter files before downloading based on date, spatial area, or file name. Choose from various download options, such as Python script. Export bounding boxes as a GeoJSON.https://nsidc.org/support/how/search-filter-and-order-nsidc-dataVIEW RELATED INFORMATIONHow to filter and order from a data set web pagePublicationURLhttps://nsidc.org/data/user-resources/help-center/how-to-use-earthdata-downloadVIEW RELATED INFORMATIONHow to use Earthdata DownloadPublicationURLDATA SEARCHDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User ServicesEmailnsidc@nsidc.orgDEVELOPERPUBLISHERSERVICE PROVIDERNASA National Snow and Ice Data Center Distributed Active Archive Centerhttps://nsidc.org/daac/NASA NSIDC DAAC2025-04-16T00:00:00.000ZChromeFirefoxSafariSee https://github.com/nsidc/data-access-tool-ui/blob/main/CHANGELOG.md for more information on the latest version.https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0https://nsidc.org/data/data-access-tool/SPL1BTB/versions/6/application/vnd.nasa.cmr.umm+jsonfalsecrumlydmmt_tool_12821TL4019517520-NSIDC_CPRDNSIDC_CPRD1tool2026-02-11T17:45:02.724ZGOTO WEB TOOLhttps://search.earthdata.nasa.gov/searchDistributionURLNSIDC_CPRD_NASA_Earthdata_SearchWeb User Interface1NASA Earthdata SearchSearch and order data from all NASA DAACs using spatial and temporal filters in a map interface. Reformatting, reprojecting, and subsetting options are available for some data sets.https://nsidc.org/support/how/search-order-and-customize-nsidc-daac-data-nasa-earthdata-searchVIEW RELATED INFORMATIONHow to search, order, and customize data with NASA Earthdata SearchPublicationURLDATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESDATA SEARCHDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC DAAC User ServicesEmailnsidc@nsidc.orgSERVICE PROVIDEREarthdata Service DeskEmailsupport@earthdata.nasa.govAUTHORDEVELOPERORIGINATORPUBLISHERMaintenance and Development, Earth Observing System Data and Information System, Earth Observing System,Goddard Space Flight Center, NASAhttp://newsroom.gsfc.nasa.gov/NASA/GSFC/EOS/EOSDIS/EMDChromeFirefoxSafariThis is the most current release of this tool.https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0https://search.earthdata.nasa.gov/search/granules?p=C2938661904-NSIDC_CPRDapplication/vnd.nasa.cmr.umm+jsonfalsecrumlydmmt_tool_12447TL4019526230-NSIDC_CPRDNSIDC_CPRD1tool2026-02-11T17:47:57.097ZGOTO WEB TOOLhttps://worldview.earthdata.nasa.gov/DistributionURLNSIDC_CPRD_WORLDVIEWWeb User Interface1NASA WorldviewBrowse and display global satellite imagery layers from NASA GIBS. Download raw data, share screenshots, and create animations from the imagery.https://nsidc.org/support/how/visualize-and-download-nsidc-data-nasa-worldviewVIEW RELATED INFORMATIONHow to visualize and download data with NASA WorldviewPublicationURLDATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESDATA SEARCHDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA INTEROPERABILITYDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESDATA REFORMATTINGDATA CUSTOMIZATIONDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESGEOGRAPHIC INFORMATION SYSTEMSDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User Services OfficeEmailnsidc@nsidc.orgSERVICE PROVIDERWorldviewEmailsupport@earthdata.nasa.govDEVELOPERPUBLISHERSERVICE PROVIDERMaintenance and Development, Earth Observing System Data and Information System, Earth Observing System,Goddard Space Flight Center, NASAhttp://newsroom.gsfc.nasa.gov/NASA/GSFC/EOS/EOSDIS/EMDSee https://github.com/nasa-gibs/worldview/releases for more information on the latest version.https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0GEOTIFFGIFJPEGKMLPNGhttps://worldview.earthdata.nasa.gov/?v=-186,-77,170,87&l=SMAP_L1_Passive_Faraday_Rotation_Fore,SMAP_L1_Passive_Faraday_Rotation_Aft,Coastlines_15m,MODIS_Terra_CorrectedReflectance_TrueColor