BR Köppen Climate Classification Calculator

Koppen-Geiger climate classification in Brazil

The Koppen-Geiger system goes back to Wladimir Koppen in 1900, with later refinements by Rudolf Geiger (1936) and, more recently, Peel, Finlayson and McMahon (2007) and Alvares et al. (2013). It sorts climates by monthly mean temperature and by how much rain falls and when. Each type gets a two- or three-letter code. The first letter (A-E) sets the main group, the second describes the rainfall regime, the third the thermal regime. Take Aw: tropical (A) with a dry winter (w), the signature of the Brazilian Cerrado.

Most of Brazil falls into the A and C classes. You find Af (equatorial, in the Amazon basin), Am (tropical monsoon, along coastal Amazonia), Aw (tropical savanna, the most widespread of all and the one that blankets the Cerrado), BSh (hot semi-arid, the sertao of the Northeast), Cfa (humid subtropical, southern Brazil and the Sao Paulo lowlands), Cfb (oceanic with a mild summer, on the southern plateaus and the serras of MG/SP/RS), plus Cwa and Cwb (dry-winter subtropical of altitude, common in the central-eastern uplands). The cutoffs rest on monthly mean temperatures, such as the coldest month above or below 18 degrees C, 0 degrees C or -3 degrees C, alongside rainfall thresholds tied to the annual temperature.

Applications

INMET, EMBRAPA Climapest and IBGE rely on it for their official climate maps. Undergraduate courses in Geography, Agronomy and Forestry use it to teach climate zoning, and agricultural planners use it to draw suitability zones for crops like coffee (Cwa/Cwb), sugarcane (Aw) and apples (Cfb). It also underpins the high-resolution Brazilian Koppen map of Alvares et al. (2013), which gets cited again and again in climate change research.

FAQ

Which Koppen class covers the largest area of Brazil? That would be Aw, tropical with a dry winter. It dominates roughly 60% of the country, covering most of the Cerrado and stretches of the Northeast and Southeast.

What is the difference between Cfa and Cfb? Both are humid temperate with no dry season. The split is the warmest month: Cfa hits 22 degrees C or more, giving hot summers like Porto Alegre, whereas Cfb stays under 22 degrees C, with the milder summers of Curitiba or Campos do Jordao.

How does this calculator decide the class? It runs the simplified Koppen criteria over three inputs: annual mean temperature, annual precipitation and coldest-month temperature. From those it returns the main group letter and the most likely subtype. That is plenty for classroom use and a quick zoning check.