Discuss the important features of Koppen's climatic classification

Important features of Koppen's climatic classification

Wladimir Koppen produced an empirical (quantitative) classification of world climates whose main features are:

• Based on temperature and rainfall: it uses actual measured monthly and annual values of temperature and precipitation as the criteria, rather than causes of climate.
• Based on vegetation: the boundaries between climatic types are chosen to correspond with the limits of natural vegetation belts, on the assumption that vegetation reflects climate.
• Uses a system of letters: each climate is given a code of letters. The first (capital) letter gives the five major groups: A (tropical rainy), B (dry), C (warm temperate/mesothermal), D (cold temperate/microthermal) and E (polar). A special H is sometimes added for highland climates.
• Second and third letters give sub-types: the second letter describes the seasonal rainfall (e.g. f = rain all year, w = dry winter, s = dry summer, m = monsoon), and a third letter gives finer temperature detail. This gives combinations such as Af (equatorial), Aw (tropical wet-and-dry/savanna), BW (desert), BS (steppe), Cf, Cs (Mediterranean), etc.
• Defined by fixed temperature/rainfall limits: each group has precise threshold values (for example the 18°C isotherm for the coldest month separates A from C, and dryness is defined by a temperature-rainfall formula), making the scheme objective and easy to map.

Its strengths are that it is quantitative, worldwide and easy to apply; its weakness is that it stresses average values and vegetation rather than the atmospheric causes of climate.