Ptolemy’s World of Climates

idrisi1 Ptolemy’s World of ClimatesArab geography and Christian cartography get their respective inspirations from the same sources but at different scales and manners. Under the Abbasid caliphate Greek, Persian, and Indian scriptures are translated. The latter allows Arab geographers to develop their knowledge and makes them access new geographic skills. Prior to that, they had only notions of cosmogony. Ptolemy provides the first documentation to Arabs and Christians. However Arabs modify some of Ptolemy’s work and do not always integrate Greek heritage as it is.

Y.K. Fall differentiates between Greek cartography and Ptolemy’s document. The first distinguishes between the Earth, represented as a flat disc, and its inhabited areas. Greek scholars think that the Earth is surrounded by the sea. Whereas Ptolemy holds the view that land surrounds the sea and that there is interpenetration between continental and maritime masses. He lays emphasis on cities and ports as being symbols of civilization. The primordial concept from the Ptolemyan geography that considerably holds sway over Christian sciences and most importantly Arab sciences is that of the division of the world into latitudes and climates.

In Ptolemy’s work, the world is divided into latitudes from the equator to the 45th parallel north. Beyond this line the subdivisions are organised according to climates. The latter corresponds to the best known parts of the world which appears essential to be deeply studied. The use of this theory – that is to say the division of the world into climates – varies according to geographers. However, they share a common knowledge of central climates, which is where the Islamic world plays its role.

The term climate, iklim in Arabic comes from the geek klima, which means inclination, i.e the one of the Earth towards the pole from the equator line. This idea involves another translation of klima that is region (of the earth sphere). The notion of climate refers to an area spreading in longitude from one and end to the other end of the inhabited world, lying in latitude between two parallels.

Climates bring together cities, mountains, water streams and minerals and are defined according to their astral contexts. Arab tradition establishes seven climates for the inhabited area of the earth. In the scriptures that attempt to describe the globe, the most significant theme is the one that deals with central climate that it is the fourth climate. This climate is located in Mesopotamia and represents a balance in everything.
In the adab (ancient rules and tradition of good behaviour) geography, we find this privileged theme of the fourth climate. Al Razi (Geographer of the 10th century) locates Spain in the same climate as Bagdad, exalting its wealth and advantages in order to justify the comparison with Iraq. Idrisi (geographer of the 12th century) always associates each country or city with a climate. Therefore we can argue that this tradition travels throughout history and geographic types.

Some disagree with this theory. They are those who work under an administration and prefer to interpret iklim as being a country brought together around a county town.

There are those who are inspired by another sense of the word originating from Persia. Keshwar describes the seven kingdoms of the world, of which six (India, China, Turcs, Rum, Africa, Arabia) are spread around the central kingdom of Persia. The number seven does not appear with Ptolemy but we find again this idea of a central climate prevailing over the others. The difference here is that the Persian climate is a politico-ethnic concept and no more a geodesic one.

Christian geographers divide the world into five climates or celestial zones. Each zone is determined by the yearly sun circumambulation inside the ecliptic. At the centre there is an uninhabitable zone. At each end we find a cold, boreal and austral and uninhabitable zone and in between lie two temperate zones. Christians were concerned by pragmatism and the supremacy of a zone over the other does not appear. However the idea of dividing the world into climates reveals the Ptolemyan influence within the cartographers.

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By Morad Ouasti

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