2-byte HydroClass Format (DB_HCLASS2)
The interpretation of the 8 least significant
bits is the same as the 1-byte format, except that 65535 (0xFFFF) is used for
area not scanned.
The currently available identification methods
(as of IRIS/RDA 8.12.6) can be accommodated in the 8 least significant bits of
DB_HCLASS2, see 1-byte HydroClass Format (DB_HCLASS).
As default, the remaining 8 most significant
bits of DB_HCLASS2 replicate the same formatting as the lower 1-byte bits,
for support of three further identification methods. They are reserved for future uses, such
as re-analysis of precipitation type at surface.
It is also possible to merge the bit segments
by combining the segments within the 8 most significant bits, multiplicatively. In that
scenario, the DB_HCLASS2 data type can support a user specified
identification method in large bases up to 7x7x3= 147 classes.
