1 1 MEAN SEA SURFACE (MSS) INTERPOLATION FLAG
2 2 OCEAN TIDE SOLUTION 1 INTERPOLATION FLAG (0= 4 POINTS OVER OCEAN, 1=LESS THAN 4 POINTS)
3 3 OCEAN TIDE SOLUTION 2 INTERPOLATION FLAG (0= 4 POINTS OVER OCEAN, 1=LESS THAN 4 POINTS)
4 4 METEOROLOGICAL DATA INTERPOLATION FLAG (0= 4 POINTS OVER OCEAN, 1=LESS THAN 4 POINTS)