Köppen Classification System

The major first letters are:

• A for tropical,,
• B for deserts,
• C for mesothermal,
• D for continental
• E for polar.

Note: A highland (mountain) climate is also a part of this system which is part of this classification model.

Step 1 DETERMINING THE FIRST LETTER TO A POLAR E TYPE CLIMATE

Ask This Question

Is the Climate an E type climate? Is the warmest month less than 10C or 50F? E Type climates are polar type climate.

If it is an E type climate tap here E TYPE CLIMATE.

Ask These Questions to determine a preliminary SECOND LETTER for a C or D type climate note: this is not a first letter for a climate type, but rather this step sets the characteristic of the concentration of precipitation for C and D type climates (if your climate is a C or D type climate) and this calculation will provide you with the second letter in a C or D type climate.

Does the climate have a seasonal concentration of precipitation? That is, does more than 70% of the precipitation fall in the winter or summer?

IF the precipitation is concentrated in SUMMER, then the climate is a DRY WINTER type climate and the SECOND LETTER WILL BE a small "w".

IF the precipitation is concentrated in WINTER,then the climate is a DRY SUMMER type climate and the SECOND LETTER WILL BE a small "s".

IF there is NO CONCENTRATION in either winter or summer, then the SECOND LETTER WILL BE a small "f".

In all cases, make note of this second letter and tap here.