What specific temperature characteristic is used in major climate classification systems (such as Köppen) to define the boundaries of the Tropical climate zone (Group A)?
💡 Explanation:
The defining characteristic of Tropical climates (Group A) is consistent year-round warmth. In the Köppen system, a climate is classified as Tropical if the average temperature of its coldest month is 18°C (64.4°F) or warmer, indicating minimal thermal seasonality.
