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MOD29P1N and MYD29P1N Local Sea Ice Attributes, Version 5

Local attributes describe the data and provide summary information about the results of the sea ice algorithm. Two types of local attributes are reported: Hierarchical Data Format (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 Scientific Data Set (SDS). Ice surface temperature for daily tile
Unit units International System of Units (SI) of the data. This attribute may or may not be used. degree_Kelvin
Format format How the data should be viewed in Fortran format notation F4.1
Coordinate system coordsys Coordinate system to use for the data cartesian
Range valid_range Maximum and minimum values within a selected data range 21000,31320
Fill Value _FillValue Data used to fill gaps in the swath 7
Calibration scale_factor
Value by which each data element is to be multiplied¹ 0.01
scale_factor_err Error induced by scaling¹ 0.0
add_offset Value to add to each array element¹ 0.0
add_offset_err Error induced by offset¹ 0.0
calibrated_nt HDF data types of the calibrated data¹ 23

¹ These values are only used for Ice Surface Temperature (IST).

Custom Local Attributes for the Ice Surface Temperature Field

Attribute Name
Sample Value
Key Key to the meaning of the coded integers within the SDS.
Value (after scaling)
0.0 = missing missing data
1.0 = no decision no decision
11.0 = night darkness, terminator, or polar
25.0 = land land
37.0 = inland water lake or inland water
39.0 = open ocean ocean
50.0 = cloud cloud obscured
243.0 - 273.0 = expected Ice Surface Temperature (IST) range  
655.35 = fill fill

Custom Local Attributes for the Ice Surface Temperature Spatial QA Field

Attribute Name Definition Sample Value
Key Explanation of the Quality Assessment (QA) Flag. 0 = good quality
1 = other quality
253 = land mask
254 = ocean mask
255 = fill