Data are stored in ASCII

Ice concentrations are stored as tenths of gridbox covered with ice (0-9)
Gridboxes completely ice-covered are stored as '*'
missing data are set to '-'

The  month and year are stored at the start of each month.

Data Array (360x180)
Item (1,1) stores the value for the 1-deg-area centred at 179.5W and 89.5N
Item (360,180) stores the value for the 1-deg-area centred at 179.5E and 89.5S

          ----- -----
         |     |     |
         | MON | YR  |
         |_____|_____|__________________________________
     90N |(1,1)                                         |
         |                                              |
         |                                              |
         |                                              |
         |                                              |
         |(1,90)                                        |
     Equ |                                              |
         |(1,91)                                        |
         |                                              |
         |                                              |
         |                                              |
         |                                              |
     90S |(1,180)______________________________(360,180)|
          180W                 0                    180E