Level3 25 km Brightness Temperature & Sea Ice Concentration Data Fields
The following notations are used throughout this document:
Int8  8bit (1byte) signed integer 
Int16  16bit (2byte) signed integer 
NT2  Enhanced NASA Team algorithm 
ABA  AMSR Basic Algorithm 
North polar grids are 304 pixels by 448 pixels.
South polar grids are 316 pixels by 332 pixels.
Parameter 
Data Type 
Description 
Scale Factor 


SI_25km_SH_06V_ASC  Int16 
6.9 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 kelvin (K) 
Multiply data values by 0.1 to obtain units in kelvin (K)  
SI_25km_SH_06V_DSC  Int16 
6.9 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_06V_DAY  Int16 
6.9 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_06H_ASC  Int16 
6.9 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_06H_DSC  Int16 
6.9 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_06H_DAY  Int16 
6.9 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10V_ASC  Int16 
10.7 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10V_DSC  Int16 
10.7 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10V_DAY  Int16 
10.7 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10H_ASC  Int16 
10.7 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10H_DSC  Int16 
10.7 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_10H_DAY  Int16 
10.7 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18V_ASC  Int16 
18.7 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18V_DSC  Int16 
18.7 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18V_DAY  Int16 
18.7 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18H_ASC  Int16 
18.7 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18H_DSC  Int16 
18.7 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_18H_DAY  Int16 
18.7 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23V_ASC  Int16 
23.8 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23V_DSC  Int16 
23.8 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23V_DAY  Int16 
23.8 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23H_ASC  Int16 
23.8 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23H_DSC  Int16 
23.8 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_23H_DAY  Int16 
23.8 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36V_ASC  Int16 
36.5 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36V_DSC  Int16 
36.5 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36V_DAY  Int16 
36.5 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36H_ASC  Int16 
36.5 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36H_DSC  Int16 
36.5 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_36H_DAY  Int16 
36.5 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89V_ASC  Int16 
89.0 GHz vertical, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89V_DSC  Int16 
89.0 GHz vertical, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89V_DAY  Int16 
89.0 GHz vertical, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89H_ASC  Int16 
89.0 GHz horizontal, daily average ascending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89H_DSC  Int16 
89.0 GHz horizontal, daily average descending T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_89H_DAY  Int16 
89.0 GHz horizontal, daily average T_{b}s Valid range: approximately 50 to 300 K 
Multiply data values by 0.1 to obtain units in K  
SI_25km_SH_ICECON_ASC  Int16  Sea ice concentration, daily ascending average

N/A  
SI_25km_SH_ICECON_DSC  Int16  Sea ice concentration daily descending average

N/A  
SI_25km_SH_ICECON_DAY  Int16  Sea ice concentration daily average

N/A  
SI_25km_SH_ICEDIFF_ASC  Int16  Sea ice concentration daily ascending average, using the difference between ABA and NT2 algorithms

N/A  
SI_25km_SH_ICEDIFF_DSC  Int16  Sea ice concentration daily descending average, using the difference between ABA and NT2 algorithms

N/A  
SI_25km_SH_ICEDIFF_DAY  Int16  Sea ice concentration daily average, using the difference between ABA and NT2 algorithms

N/A  
^{*} Positive values 1 to 100% represent the difference in concentration where NT2 is greater than BBA and negative values 1 to 100% represent the difference in concentration where BBA is greter than NT2. ^{**}The difference values need input from both the NT2 and ABA sea ice concentration algorithms. These new values indicate when one of these is missing. If there is a valid ABA value and missing NT2, it takes on the value 200+ABA. Like wise, a valid NT2 and missing ABA takes on the value 200NT2. A difference value of 200 means the ABA was open water and the NT2 was missing; a value of 225 means the ABA was 25% and the NT2 was missing. So I guess a value of 300 means ABA was 100 and NT2 was missing. The normal range of difference values is 100 to 100. 