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MOD29P1D Local Attributes

Local attributes describe the data and provide summary data on the results of the sea ice algorithm. Two types of local attributes are reported: HDF predefined, and custom local attributes.

HDF Predefined Local Attributes

Attribute Name Reserved Label(s) Definition Sample Value
Label long_name Long name of the SDS Sea ice by reflective characteristics
Unit units SI units of the data, if any none
Format format How the data should be viewed in Fortran format notation I3
Coordinate system coordsys Coordinate system to use for the data cartesian
Range valid_range Max and min values within a selected data range 0-254
Fill Value _FillValue Data used to fill gaps in the swath 255
Calibration scale_factor
scale_factor_err
add_offset
add_offset_err
calibrated_nt
Used if data are stored in calibrated form



Custom Local Attributes

Sea Ice by Reflectance
Attribute Name Definition Sample Value
missing_value Coded integer used to indicate missing data 0
Sea Ice_pct Areal coverage of sea ice (0-100) 68
Ocean_pct Percentage of ocean in the tile 57
Cloud_pct Percentage of cloud in the tile 75
Land_area_pct Percentage of land in the tile 43
Key Key to meaning of data See pixel values.


Sea Ice by Reflectance SpatialQA
Attribute Name Definition Sample Value
Nominal_results Percentage of nominal data in the tile 14
Abnormal_results Percentage of abnormal data in the tile 1
Invalid_input Percentage of invalid data in the tile 85
Cloud_obscured Percentage of cloud in the tile
Outside_relative_azimuth Percentage of land in the tile 0
Key: See MODIS Sea Ice Quality Assurance Fields for definition of bit values


Ice Surface Temperature
Attribute Name Definition Sample Value
Key: Key to meaning of data See pixel values.


Ice Surface Temperature SpatialQA
Attribute Name Definition Sample Value
Nominal_results Percentage of nominal data in the tile 89
Abnormal_results Percentage of abnormal data in the tile 1
Invalid_input Percentage of invalid data in the tile 0
Cloud_obscured Percentage of cloud in the tile 10
Outside_relative_azimuth Percentage of land in the tile 0
Key: See MODIS Sea Ice Quality Assurance Fields for definition of bit values


Sea Ice by IST
Attribute Name Definition Sample Value
missing_value Coded integer used to indicate missing data 0
Cloud_cover Percentage of cloud-obscured ocean 91
Ocean_percentage Percentage of ocean in the tile 93
Sea_ice_percentage Areal coverage of sea ice 0
No_decision Percentage of no decision results 1
Invalid_input_data Percentage of invalid data in the tile 0
Key Key to meaning of data See pixel values.


Combined Sea Ice
Attribute Name Definition Sample Value
Key: Key to meaning of data See pixel values.

¹ These percentages are based on the total number of pixels in the swath (x dimensions * y dimensions).