Köppen climate classification

The Köppen climate classification is a way to group the world's climates into five main types. These types are based on how much rain or snow a place gets and how hot or cold it is. The five groups are tropical, arid, temperate, continental, and polar. Each group is shown by a letter.

For example, Af means a tropical rainforest climate, where it is warm and rainy all year. Another example is Cfb, which describes an oceanic climate with warm summers.

Scientists all around the world use this system to talk about and study different climates. It was first created by a scientist named Wladimir Köppen in 1884. Köppen was also a botanist, so he designed the system based on what kinds of plants can grow in each climate. This helps us understand what kinds of plants and animals might live in different places.

The Köppen system has been changed a few times since it was first made. Another scientist named Rudolf Geiger added some changes in the 1950s, and the system is sometimes called the Köppen–Geiger climate classification. A different system called the Trewartha climate classification was made in 1966 to make some parts of the Köppen system even clearer.

Overview

Further information: List of cities by Köppen climate classification

The Köppen climate classification sorts Earth's climates into five main groups: A (tropical), B (arid), C (temperate), D (continental), and E (polar). Each group is divided into smaller types based on rainfall and temperature.

Group A: Tropical climates

Tropical climates are very warm all year, with average temperatures of at least 18 °C (64.4 °F) every month and lots of rain.

• Af = Tropical rainforest climate; rain every month.
• Am = Tropical monsoon climate; one very dry month each year.
• Aw or As = Tropical wet and dry or savanna climate; a long dry season.

Group B: Desert and semi-arid climates

Desert and semi-arid areas get very little rain.

The amount of rain tells us if it is a desert (BW) or a steppe (BS). Some deserts are hot (BWh) and some are cold (BWk). Some areas are semi-arid and hot (BSh) and some are semi-arid and cold (BSk).

Group C: Temperate climates

Temperate climates have cold winters and warm summers. The coldest month is between 0 °C (32 °F) and 18 °C (64.4 °F), and at least one month is above 10 °C (50 °F).

• Cfa = Humid subtropical climate; hot summers, no dry season.
• Cfb = Temperate oceanic climate or subtropical highland climate; mild summers, no dry season.
• Cfc = Subpolar oceanic climate; cool summers, no dry season.
• Cwa = Monsoon-influenced humid subtropical climate; hot summers, dry winters.
• Cwb = Subtropical highland climate or Monsoon-influenced temperate oceanic climate; mild summers, dry winters.
• Cwc = Cold subtropical highland climate or Monsoon-influenced subpolar oceanic climate; cool summers, dry winters.
• Csa = Hot-summer Mediterranean climate; hot, dry summers and wet winters.
• Csb = Warm-summer Mediterranean climate; warm, dry summers and wet winters.
• Csc = Cold-summer Mediterranean climate; cool, dry summers and wet winters.

Group D: Continental climates

Continental climates have very cold winters and warm summers. At least one month is below 0 °C (32 °F) and at least one month is above 10 °C (50 °F).

• Dfa = Hot-summer humid continental climate; hot summers, no dry season.
• Dfb = Warm-summer humid continental climate; warm summers, no dry season.
• Dfc = Subarctic climate; short, cool summers, no dry season.
• Dfd = Extremely cold subarctic climate; very cold winters, short, cool summers, no dry season.
• Dwa = Monsoon-influenced hot-summer humid continental climate; hot summers, dry winters.
• Dwb = Monsoon-influenced warm-summer humid continental climate; warm summers, dry winters.
• Dwc = Monsoon-influenced subarctic climate; short, cool summers, dry winters.
• Dwd = Monsoon-influenced extremely cold subarctic climate; very cold winters, short, cool summers, dry winters.
• Dsa = Mediterranean-influenced hot-summer humid continental climate; hot, dry summers and wet winters.
• Dsb = Mediterranean-influenced warm-summer humid continental climate; warm, dry summers and wet winters.
• Dsc = Mediterranean-influenced subarctic climate; cool, dry summers and wet winters.
• Dsd = Mediterranean-influenced extremely cold subarctic climate; very cold winters, cool, dry summers and wet winters.

Group E: Polar and alpine climates

Polar and alpine climates are very cold all year, with every month below 10 °C (50 °F).

• ET = Tundra climate; short, cool summers.
• EF = Ice cap climate; always very cold.

Group A: Tropical/megathermal climates

Tropical climates stay warm all year. Every month is at least 18 °C (64.4 °F), and there is usually a lot of rain. There are three main types:

Af: Tropical rainforest climate

Main article: Tropical rainforest climate

All months have at least 60 mm (2.4 in) of rain. These places are close to the equator and often very wet all year. Temperatures stay warm.

Am: Tropical monsoon climate

Main article: Tropical monsoon climate

Monsoon winds change the rain each season. The driest month has less than 60 mm (2.4 in) of rain, but it is still wet.

Aw/As: Tropical savanna climate

Main article: Tropical savanna climate

Aw: Tropical savanna climate with dry winters

Aw climates have a dry season. The driest month has less than 60 mm (2.4 in) of rain. These areas are often found between 10° and 25° latitude.

Group C: Temperate/mesothermal climates

Main article: Temperate climate

Temperate climates have mild winters and warm summers. The coldest month is above 0 °C but below 18 °C. These climates can have different rainfall patterns.

The second letter shows the rainfall pattern. "w" means dry winters, "s" means dry summers, and "f" means rain all year. The third letter shows how hot the summers are. "a" means hot summers, "b" means warm summers, and "c" means cool summers.

Cs: Mediterranean-type climates

Main article: Mediterranean climate

Csa: Hot-summer Mediterranean climates

These climates are found on the western sides of continents between 30° and 45° latitude. Winters are mild and rainy, while summers are hot and dry.

Csb: Warm-summer Mediterranean climates

These climates are similar but have cooler summers, often found around 40° latitude.

Csc: Cold-summer Mediterranean climates

These rare climates have cold summers and are found in high mountain areas.

Cfa: Humid subtropical climates

Main article: Humid subtropical climate

These climates are found on the eastern sides of continents near the equator. They have hot, wet summers and mild winters.

Cfb: Oceanic climates

Main article: Oceanic climate

Marine west coast climate

Cfb climates are found on the western sides of continents in the mid-latitudes. They have mild, wet weather all year.

Subtropical highland climate with uniform rainfall

Main article: Oceanic climate § Subtropical highland variety (Cfb, Cwb)

These climates are found in high mountains and have rain spread evenly through the year.

Cfc: Subpolar oceanic climate

These climates are found near the poles on coastal areas or islands.

Cw: Dry-winter subtropical climates

Cwa: Dry-winter humid subtropical climate

Cwa climates have dry winters and wet summers, found in regions with monsoons.

Cwb: Dry-winter subtropical highland climate

These climates are found in high mountains in the tropics and subtropics, with dry winters and wet summers.

Cwc: Dry-winter cold subtropical highland climate

These rare climates are found in high mountains in South America and Southeast Asia.

Group D: Continental/microthermal climates

Main article: Continental climate

These climates have warm summers but very cold winters. The warmest month averages above 10 °C (50 °F), while the coldest month averages below 0 °C (32 °F). These climates are usually found deep inside continents or on their upper east coasts, mostly north of 40°N. They are rare in the Southern Hemisphere because there is less land there at these latitudes, except in some high mountain areas.

Dfa/Dwa/Dsa: Hot summer humid continental climates

Main article: Hot-summer humid continental climate

Dfa climates have very hot summers, with the warmest month averaging more than 22 °C (72 °F). These are usually found in the mid-latitudes, such as in parts of North America and Europe. Dsa climates are found at higher elevations near areas with hot, dry summers. These climates only exist in the Northern Hemisphere because the Southern Hemisphere does not have large areas of land far enough from the sea’s influence.

In eastern Asia, Dwa climates reach further south because of the strong Siberian high-pressure system. This system makes winters dry and summers very wet due to monsoon winds.

Dfb/Dwb/Dsb: Warm summer humid continental/hemiboreal climates

Main article: Warm-summer humid continental climate

Dfb climates have warm summers and are found just north of the hot summer continental climates. They are common in the mid to high latitudes of North America and Asia, and also in parts of Europe. Like all Group D climates, Dwb climates are mostly found in the Northern Hemisphere. Dsb climates occur at higher altitudes or latitudes, mainly in North America, where Mediterranean climates reach further north than in Eurasia.

Dfc/Dwc/Dsc: Subarctic/boreal climates

Main article: Subarctic climate

Dfc, Dsc, and Dwc climates are found further north or at higher elevations, usually between 50° and 60° latitude.

Dfd/Dwd/Dsd: Subarctic/boreal climates with severe winters

Places with this climate have extremely cold winters, with the coldest month averaging below −38 °C (−36 °F). These climates are found only in eastern Siberia and are among the coldest places on Earth.

Group E: Polar climates

In the Köppen climate system, polar climates are places where the warmest temperature of any month is always below 10 °C (50 °F). These climates have two types: tundra climates and ice cap climates.

ET: Tundra climate

Main article: Tundra climate

Tundra climate (ET): the warmest month averages between 0 °C (32 °F) and 10 °C (50 °F). You can find these climates on the northern edges of North America and Eurasia, usually north of 70 °N. They also appear on islands near the Antarctic Convergence and on high mountains above the tree line.

EF: Ice cap climate

Main article: Ice cap climate

Ice cap climate (EF): this climate is most common in Antarctica, inner Greenland, and on the tops of many high mountains, even at lower latitudes. The monthly average temperature here never goes above 0 °C (32 °F).

Ecological significance

The Köppen climate classification helps us learn how weather affects plants and nature. It groups places by their temperature and rain, showing what plants can grow there.

Scientists now use this system to see how climate change impacts Earth. Some places have grown drier and warmer, changing what plants can live there. These changes happen because of things people do.

Other Köppen climate maps

All maps use the ≥0 °C (32 °F) definition for the temperate-continental border.

• North America

• Europe

• Russia

• Central Asia

• East Asia

• South America

• Africa

• Western Asia

• South Asia

• Southeast Asia

• Melanesia/Oceania

• Australia

• New Zealand

• World (1991–2020)

• World (2071–2099, SSP245)