UCAR-CU CYGNSS Level 3 Soil Moisture Version 1.0

(CYGNSS_L3_SOIL_MOISTURE_V1.0)
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
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-May-17
 
Projection
Projection Type: Lambert Cylindrical Equal Area
Projection Detail: WGS 84 / NSIDC EASE-Grid 2.0 Global
 
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
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
DATA CITATION POLICY
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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For more information see Data Citations and Acknowledgments.

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

VersionDatasetVersion DateStatus
3.2CYGNSS Level 3 Soil Moisture Version 3.22024-04-10ACTIVE2024-04-10T19:46:00.000Z
1.0UCAR-CU CYGNSS Level 3 Soil Moisture Version 1.02022-04-11ACTIVE2022-04-11T17:36:00.000Z