MOD29 and MYD29 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 Scinetific Data Set (SDS). Sea ice by reflective characteristics
Unit units International System of Units (SI) of the data. This attribute may or may not be used. 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 Maximum and minimum values of valid data. 0,254
Fill Value _FillValue Data used to fill gaps in the swath 255
Calibration scale_factor Value by which each data element is to be multiplied. (Ice Surface Temperature (IST) only). 0.01
scale_factor_err Error induced by scaling. (IST only). 0.0
add_offset Value to add to each array element. (IST only). 0.0
add_offset_err Error induced by offset. (IST only). 0.0
calibrated_nt HDF data types of the calibrated data. (IST only). 5 (float 32)


Custom Local Attributes for the Sea Ice by Reflectance Field

Attribute Name
Definition
Sample Value
Key Key to the meaning of the coded integers within the SDS.
Value
Description
0 = missing data
L1B data missing
1 = no decision
no decision
11 = night
darkness, terminator, or polar
25 = land
snow-free land
37 =inland water
lake or inland water
39 = ocean
open water
50 = cloud
cloud obscured
100 = lake ice
snow-covered lake ice
200 = sea ice
snow-covered sea ice
254 = detector saturated
detector saturated
255 = fill
fill
Nadir_data_resolution Nominal spatial resolution of the pixels at nadir. 1 km
Valid EV Obs Band 2 (%) Percentage¹ of valid observations from Level 1B in Band 2 of the swath. 77.83251
Valid EV Obs Band 4 (%) Percentage¹ of valid observations from Level 1B in Band 4 of the swath. 77.83248
Valid EV Obs Band 6 (%) Percentage¹ of valid observations from Level 1B in Band 6 of the swath. 77.709114
Saturated EV Obs Band 2 (%) Percentage¹ of saturated observations from Level 1B in Band 2 of the swath. 0.0
Saturated EV Obs Band 4 (%) Percentage¹ of saturated observations from Level 1B in Band 4 of the swath. 0.0
Saturated EV Obs Band 6 (%) Percentage¹ of saturated observations from Level 1B in Band 6 of the swath. 0.0

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


Custom Local Attributes for the Ice Surface Temperature Field

Attribute Name
Definition
Sample Value
Key Key to the meaning of the scaled values within the SDS.
Value
Description
0.0 = missing data
L1B data missing
1.0 = no decision
no decision
11.0 = night
darkness, terminator, or polar
25.0 = land
snow-free land
37.0 = inland water
lake or inland water
39.0 = open ocean
open water
50.0 = cloud
cloud obscured
243.0 - 273.0 = expected Ice Surface Temperature (IST) range
 
655.35 = fill
fill

Valid EV Obs Band 31 Percentage of valid observations from level 1B in band 31 in the swath. 100.0
Valid EV Obs Band 32 Percentage of valid observations from level 1B in band 32 in the swath. 100.0
Saturated EV Obs Band 31 Percentage of saturated observations from level 1B in band 31 in the swath. 0.0
Saturated EV Obs Band 32 Percentage of saturated observations from level 1B in band 32 in the swath. 0.0


Custom Local Attributes for the Sea Ice by Reflectance Pixel QA Field

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



Custom Local Attributes for the Ice Surface Temperature Pixel QA Field

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



Custom Local Attributes for the Latitude Field

Attribute Name
Definition
Sample Value
Source Where the geolocation information came from. MOD03 geolocation product; data read from center pixel in 5 km box.


Custom Local Attributes for the Longitude Field

Attribute Name
Definition
Sample Value
Source Where the geolocation information came from. MOD03 geolocation product; data read from center pixel in 5 km box.