UCAR-CU CYGNSS Level 3 Soil Moisture Version 1.0

(CYGNSS_L3_SOIL_MOISTURE_V1.0)
1 Publication Cited this Dataset
Citation metrics available for years (2014-2022)
Version1.0
Processing Level3
Start/Stop Date2017-Mar-18 to Present
Short NameCYGNSS_L3_SOIL_MOISTURE_V1.0
DescriptionThe CYGNSS Level 3 Soil Moisture Product provides volumetric water content estimates for soils between 0-5 cm depth at a 6-hour discretization for most of the subtropics. The data were produced by CYGNSS investigators at the University Corporation for Atmospheric Research (UCAR) and the University Colorado at Boulder (CU), and derive from version 2.1 of the CYGNSS L1 SDR. The soil moisture algorithm uses collocated soil moisture retrievals from SMAP to calibrate CYGNSS observations from the same day. For a given location, a linear relationship between the SMAP soil moisture and CYGNSS reflectivity is determined and used to transform the CYGNSS observations into soil moisture. The data are archived in daily files in netCDF-4 format. Two soil moisture variables report the volumetric water content in units of cm3/cm3. The variable SM_subdaily includes up to four soil moisture estimates per day. Another variable SM_daily provides a daily average. The time series covers the period from March 2017 to present.
DOI10.5067/CYGNU-L3SM1
MeasurementLAND SURFACE > SOILS > SOIL MOISTURE/WATER CONTENT
Platform/Sensor
CYGNSS
Platform
Name: Cyclone Global Navigation Satellite System (CYGNSS)
Orbit Period: 94.0 minutes
Inclination Angle: 35.0 degrees
/
DDMI
SENSOR
Name: Delay Doppler Mapping Instrument (DDMI)
Swath Width: 25.0 kilometers
Description: Spacecraft angular distance from orbital plane relative to the Equator.

ProjectCyclone Global Navigation Satellite System (CYGNSS)
Data ProviderPublisher: PO.DAAC
Creator: CYGNSS
Release Place: PO.DAAC
Release Date: 2020-Oct-16
Resource: https://cygnss.engin.umich.edu/

FormatnetCDF-4
Keyword(s)cygnss, level 3, l3, soil moisture, bistatic radar, cosmic, ucar, cu, version 1.0, v1.0, version 1, v1
Questions related to this dataset? Contact podaac@podaac.jpl.nasa.gov
Resolution
Spatial Resolution: 0.3 Decimal Degrees x 0.37 Decimal Degrees
Temporal Resolution: Hourly - < Daily
 
Coverage
Region: GLOBAL
Region: TROPICS
North Bounding Coordinate: 38 degrees
South Bounding Coordinate: -38 degrees
West Bounding Coordinate: -135 degrees
East Bounding Coordinate: 164 degrees
Time Span: 2017-Mar-18 to Present
Granule Time Span: 2017-Mar-18 to 2024-Jun-28
 
Projection
Projection Type: Lambert Cylindrical Equal Area
Projection Detail: WGS 84 / NSIDC EASE-Grid 2.0 Global
 
Capabilities
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OPENDAP DATA
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This dataset can be downloaded using the podaac-data-subscriber (the recommended tool for bulk downloading PO.DAAC data). It is a Python package for downloading one or many files using the command line interface. The URL redirects to the data-subscriber home page with instructions for utilizing the tool
DIRECT S3-ACCESS
Available for access in-region with AWS Cloud
Region
us-west-2
Bucket/Object Prefix: Protected buckets contain the data files for a given collection. Protected simply means users must log in to Earthdata Login before gaining access to contents within that S3 Bucket. Please use the S3Credential endpoint to gain an Earthdata login token for use in S3 Access.

Public buckets, in contrast, house metadata such as checksums, imagery, and metadata files and the like. A user can access public buckets and these types of files without logging in to Earthdata Login.

Most of the time, you'll want to access the protected bucket Information
podaac-ops-cumulus-protected/CYGNSS_L3_SOIL_MOISTURE_V1.0/
podaac-ops-cumulus-public/CYGNSS_L3_SOIL_MOISTURE_V1.0/
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NameLong NameUnit
latitudelatitudedegrees_north
longitudelongitudedegrees_east
SIGMA_dailystandard deviation of soil moisture retrievals during the 24 hr period for the grid cell1
SIGMA_subdailystandard deviation of soil moisture retrievals during the sub-daily time periods for the grid cell1
SM_dailymean soil moisture retrieval during the daily time periods for the grid cell1
SM_subdailymean soil moisture retrieval during the sub-daily time periods for the grid cell1
timetimedays since 1970-01-01 00:00:00 UTC
timeintervalsstart and stop time for the sub-daily time periodshours
DATA CITATION GUIDELINES
ANOMALIES
GENERAL DOCUMENTATION
PUBLICATIONS
  • https://doi.org/10.3390/rs12101558
    Chew, C.C., E.E. Small. 'Description of the UCAR/CU Soil Moisture Product'. Remote Sens. 2020, 12, 1558. https://doi.org/10.3390/rs12101558
  • https://doi.org/10.1029/2018GL077905
    Chew, C. C., & Small, E. E. (2018). Soil Moisture Sensing Using Spaceborne GNSSReflections: Comparison of CYGNSS Reflectivity to SMAP Soil Moisture.Geophysical Research Letters, 45(9), 4049-4057.https://doi.org/10.1029/2018GL077905
DATA RECIPE
USER'S GUIDE
Citation is critically important for dataset documentation and discovery. Please cite the data as follows, and cite the reference papers when it is appropriate.
Citation CYGNSS. 2020. UCAR-CU CYGNSS Level 3 Soil Moisture Version 1.0. Ver. 1.0. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at https://doi.org/10.5067/CYGNU-L3SM1

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Journal Reference Chew, C.C., E.E. Small.. 2020. Description of the UCAR/CU Soil Moisture Product, Remote Sens, 12, 10. https://doi.org/10.3390/rs12101558