Aristotle's Climate Zones

Think about this: depending on what part of the world you live in, you may experience very different weather and a very different climate than a fellow weather geek who, like you, is reading this article right now. 

Why We Classify Climate

Because weather differs greatly from place to place and time to time, it's unlikely that any two places will experience the same exact weather or climate. Given the many locations there are worldwide, that's quite a lot of different climates—too many to study one by one! To help make this volume of climate data easier for us to handle, we "classify" (group them by similarities) climates.  

The first attempt at climate classification was made by the ancient Greeks. Aristotle believed that each of the Earth's hemispheres (Northern and Southern) could be divided into 3 zones: the torrid, temperate, and frigid, and that Earth's five circles of latitude (the Arctic Circle (66.5° N), Tropic of Capricorn (23.5° S), Tropic of Cancer (23.5° N), equator (0°), and Antarctic Circle (66.5° S)) divided one from another. 

Because these climate zones are classified based on latitude—a geographic coordinate—they're also known as the geographic zones.

The Torrid Zone 

Because Aristotle believed the regions centered around the equator were too hot to be inhabited, he dubbed them the "torrid" zones. We know them today as the Tropics.

Both share the equator as one of their boundaries; in addition, the northern torrid zone extends to the Tropic of Cancer, and the southern, to the Tropic of Capricorn.

The Frigid Zone 

The frigid zones are the coldest regions on Earth. They are summerless and generally covered with ice and snow. 

Since these are located at Earth's poles, each is only bound by a single line of latitude: the Arctic Circle in the Northern Hemisphere, and the Antarctic Circle in the Southern Hemisphere.

The Temperate Zone

In between the torrid and frigid zones lie the temperate zones, which have features of both of the other two. In the Northern Hemisphere, the temperate zone is bound by the Tropic of Cancer and the Arctic Circle. In the Southern Hemisphere, it extends from the Tropic of Capricorn to the Antarctic Circle. Known for its four seasons—winter, spring, summer, and fall—, it is considered to be the climate of the Middle Latitudes. 

Aristotle vs. Köppen 

Few other attempts were made at classifying climate until the beginning of the 20th century, when German climatologist Wladimir Köppen developed a tool for presenting the world pattern of climates: the Köppen climate classification.  

While Köppen's system is the best-known and most widely accepted of the two systems, Aristotle's idea wasn't far wrong in theory. If Earth's surface was completely homogeneous, the map of world climates would very much resemble that theorized by the Greeks; however, because Earth isn't a homogeneous sphere, their classification is considered too simplistic.  

Aristotle's 3 climate zones are still used today when generalizing the overall weather and climate of a large swath of latitudes.