The Köppen climate classification scheme divides climates into five main climate groups: A (tropical), B (dry), C (temperate), D (continental), and E (polar). The second letter indicates the seasonal precipitation type, while the third letter

These climates are characterized by the amount of annual precipitation less than a threshold value which approximates the potential evapotranspiration. The threshold value (in millimeters) is calculated as follows:
Multiply the average

These climates have an average temperature above 10 °C (50 °F) in their warmest months, and a coldest month average below 0 °C (or −3 °C (27 °F), as noted previously). These usually occur in the interiors of continents and on their upper east coasts,

Biomass
The Köppen climate classification is based on the empirical relationship between climate and vegetation. This classification provides an efficient way to describe climatic conditions defined by temperature and

Tropical climates are characterized by constant high temperatures (at sea level and low elevations); all 12 months of the year have average

In the Köppen climate system, temperate climates are defined as having an average temperature above 0 °C (32 °F) (or −3 °C (26.6 °F), as noted

In the Köppen climate system, polar climates are defined as the warmest temperature of any month is below 10 °C (50 °F). Polar climates are further divided into two types, tundra climates and icecap climates:
ET: Tundra climate