The second letter of the Koeppen letter code gives information about:
a. the precipitation characteristics of the climate subtype.
b. the primary climate of the climate subtype.
c. the latitude of the climate subtype.
d. the temperature characteristics of the climate subtype
a. the precipitation characteristics of the climate subtype.
Explanation:
The second letter in the code represents the detailed seasonality of precipitation, it shows when during the seasons precipitation comes to that climate.