Some of the most agreeable places on the planet are found in the subtropics -- but not all subtropical climates are so hospitable, or are found where one might expect. For instance, the Gulf Stream and other currents bring warm ocean water far into the North Sea, moderating the weather of southern Iceland and much of Europe.
Dry climates -- category B -- are divided into two subcategories, BS for steppe and BW for desert. In the subtropics, average monthly temperatures never fall below freezing, so h, meaning heiss (German for "hot"), is appended.
Humid subtropical climates -- category C -- are further distinguished by adding single lower-case letters, describing typical rainfall. There are three subcategories: f indicates a location that is rainy year-round, s describes a region with a dry summer and a rainy winter, and w is just the reverse, with a dry winter and rainy summer.
By Dave Bryant, copyright 2002