VNP29 Product File Specification
Version: V1.0.0
Revision: 0
Date: 17 January 2019
ESDT: VNP29
Product name: Sea Ice
Product Level: 2
PGE: 508
Point of Contact: George Riggs
SSAI
NASA, GSFC, Code 971
Greenbelt, MD 20771
301-614-5650
George.A.Riggs.1@gsfc.nasa.gov
Principal Investigator: Dorothy K. Hall
NASA, GSFC, Code 971
Greenbelt, MD 20771
301-614-5771
Dorothy.K.Hall@nasa.gov
Co-Investigator: George Riggs
SSAI
NASA, GSFC, Code 971
Greenbelt, MD 20771
301-614-5650
George.A.Riggs.1@gsfc.nasa.gov
Mark Tschudi
University of Colorado
ECNT 320, 431 UCB, Boulder, Colorado 80309
303-492-8274
mark.tschudi@colorado.edu
Description:
The VIIRS sea ice extent algorithm and output data have been designed to be compatible with Version 6 MODIS sea ice extent
from Aqua and Terra, to ensure continuity between the collections and facilitate climate-data records (CDRs) from the three
sensors. Differences in the algorithms reflect physical differences between the instruments, for example spatial resolution
and the location of spectral bands.
Unlike MODIS, VIIRS sea ice cover and ice surface temperature (IST) are being produced as separate products: VNP29
(this data set) and VNP30 (IST). This decision allows the data to be produced at the spatial resolution of the underlying
acquisition bands, or 375 m for sea ice cover (I-band) and 750 m for IST (M-band).
SDSs produced:
SeaIceCover_Map
SeaIceCOver_Basic_QA
Algorithm_QA_Flags
latitude
longitude
The data product and algorithm are described in the VIIRS Sea Ice Data Product User Guide. The user should refer to that
document for detailed description of the product, how to interpret the product and attributes (metadata). Other information
may be found at https://nsidc.org/data/VNP29
Contents:
Global Metadata:
Name: Type: Num_Val: Source: Value:
AlgorithmType STRING 1 STIG "OPS"
AlgorithmVersion STRING 1 STIG Variable
CloudCover STRING 1 STIG Variable
Conventions STRING 1 STIG Variable
DayNightFlag STRING 1 STIG "Day"
EastBoundingCoord FLOAT 1 STIG Variable
WestBoundingCoord FLOAT 1 STIG Variable
NorthBoundingCoord FLOAT 1 STIG Variable
SouthBoundingCoord FLOAT 1 STIG Variable
GRingPointLongitude DOUBLE 4 PGE Variable
GRingPointLatitude DOUBLE 4 PGE Variable
RangeEndingDate STRING 1 PGE Variable
RangeEndingTime STRING 1 PGE Variable
RangeBeginningDate STRING 1 PGE Variable
RangeBeginningTime STRING 1 PGE Variable
StartTime STRING 1 PGE Variable
EndTime STRING 1 PGE Variable
IceCover STRING 1 STIG Variable
InputPointer STRING 3 PGE Variable
InstrumentShortname STRING 1 PGE "VIIRS"
LocalGranuleID STRING 1 PGE Variable
LongName STRING 1 STIG "VIIRS/NPP Sea Ice Cover 6-Min L2 Swath 375m"
PGEVersion STRING 1 PGE Variable
PGE_EndTime STRING 1 PGE Variable
PGE_Name STRING 1 PGE "PGE508"
PGE_StartTime STRING 1 PGE Variable
Percent_ocean_in_swath STRING 1 STIG Variable
Platform_Short_Name STRING 1 STIG "NPP"
ProcessVersion STRING 1 STIG Variable
ProcessingEnvironment STRING 1 PGE Variable
ProductionTime DATETIME1 TK Variable
ProxyDataType STRING 1 STIG "Operational Data"
Resolution STRING 1 STIG "Imagery"
SatelliteInstrument STRING 1 PGE "NPP_OPS"
ShortName STRING 1 MCF "VNP29"
cdm_data_type STRING 1 PGE "swath"
creator_email STRING 1 PGE "modis-ops@lists.nasa.gov"
creator_url STRING 1 PGE "http://ladsweb.nascom.nasa.gov"
identifier_product_doi STRING 1 PGE "10.5067/VIIRS/VNP29.001"
identifier_product_doi_authority
STRING 1 PGE "http://dx.doi.org"
institution STRING 1 PGE "NASA Goddard Space Flight Center"
keywords_vocabulary STRING 1 PGE "NASA Global Change Master Directory (GCMD) Science Keywords"
license STRING 1 PGE "http://science.nasa.gov/earth-science/earth-science-data/data-information-policy/"
naming_authority STRING 1 PGE "gov.nasa.gsfc.VIIRSland"
processing_level STRING 1 PGE "2"
project STRING 1 PGE "VIIRS Land SIPS Sea Ice Cover Project"
publisher_email STRING 1 PGE "modis-ops@lists.nasa.gov"
publisher_name STRING 1 PGE "LAADS"
publisher_url STRING 1 PGE "http://ladsweb.nascom.nasa.gov"
stdname_vocabulary STRING 1 PGE "NetCDF Climate and Forecast (CF) Metadata Convention"
title STRING 1 STIG "VIIRS Sea Ice Cover"
===============================================================================
SDS Name: latitude
Description: Latitude data
Number Type: DFNT_FLOAT32
Rank: 2
Dimension sizes:(6464,6400)
Dimension Names:
Dimension0: "number_of_lines"
Dimension1: "number_of_pixels"
SDS Attributes:
Name: Type: Num_val: Source: Value:
long_name STRING 1 PGE "Latitude data"
units STRING 1 PGE "degrees_north"
valid_range DFNT_FLOAT32 2 PGE -90.00000, 90.0000
_FillValue DFNT_FLOAT32 1 PGE -999.0000
===============================================================================
SDS Name: longitude
Description: Longitude data
Number Type: DFNT_FLOAT32
Rank: 2
Dimension sizes:(6464,6400)
Dimension Names:
Dimension0: "number_of_lines"
Dimension1: "number_of_pixels"
SDS Attributes:
Name: Type: Num_val: Source: Value:
long_name STRING 1 PGE "Longitude data"
units STRING 1 PGE "degrees_east"
valid_range DFNT_FLOAT32 2 PGE -180.00000, 180.0000
_FillValue DFNT_FLOAT32 1 PGE -999.0000
===============================================================================
SDS Name: SeaIceCover_Map
Description: Sea Ice Cover map with masks
Number Type: DFNT_UINT8
Rank: 2
Dimension sizes:(6464,6400)
Dimension Names:
Dimension0: "number_of_lines"
Dimension1: "number_of_pixels"
SDS Attributes:
Name: Type: Num_val: Source: Value:
long_name STRING string length PGE "Sea Ice Cover map with masks"
valid_range DFNT_UINT8 2 PGE 0,100
_FillValue DFNT_UNIT8 1 PGE 255
coordinates STRING 1 PGE "latitude longitude"
mask_meanings STRING 1 PGE "200-missing, 201-no_decision, 211-night, 225-land, 237-inland_water, 250-cloud, 252-unusable_L1B_data, 253-bowtie_trim, 254-no_L1B_data"
mask_values DFNT_UINT8 9 PGE 200, 201, 211, 225, 237, 250, 252, 253, 254
===============================================================================
SDS Name: Algorithm_QA_Flags
Description: Algorithm QA Flags for Ice Cover
Number Type: DFNT_UINT8
Rank: 2
Dimension sizes:(6464,6400)
Dimension Names:
Dimension0: "number_of_lines"
Dimension1: "number_of_pixels"
SDS Attributes:
Name: Type: Num_val: Source: Value:
long_name STRING string length PGE "Algorithm QA Flags for Ice Cover"
_FillValue DFNT_UNIT8 1 PGE 0
coordinates STRING 1 PGE "latitude longitude"
flag_masks STRING 1 PGE "1b, 2b, 4b, 8b, 16b, 32b, 64b, 128b"
flag_meanings STRING 1 PGE "spare low_visible_screen low_NDSI_screen spare spare high_SWIR_screen/flag spare solar_zenith_flag"
===============================================================================
SDS Name: SeaIceCover_Basic_QA
Description: Basic QA Ice Cover
Number Type: DFNT_UINT8
Rank: 2
Dimension sizes:(6464,6400)
Dimension Names:
Dimension0: "number_of_lines"
Dimension1: "number_of_pixels"
SDS Attributes:
Name: Type: Num_val: Source: Value:
long_name STRING string length PGE "Basic QA Ice Cover"
_FillValue DFNT_UNIT8 1 PGE 255
coordinates STRING 1 PGE "latitude longitude"
QA_value_meanings STRING 1 PGE "0-best, 1-good, 2-poor, 3-bad, 4-other"
mask_meanings STRING 1 PGE "211-night, 225-land, 237-inland_water, 250-cloud, 252-unusable_L1B_data, 253-bowtie_trim, 254-no_L1B_data"
mask_values DFNT_UINT8 7 PGE 211, 225, 237, 250, 252, 253, 254
valid_range DFNT_UINT8 2 PGE 0,4
===============================================================================
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