The Tropics: Background information when reading Tales from the Torrid Zone

The Tropics

This article relates to Tales from the Torrid Zone

• The tropics are the geographic region of the Earth centered on the equator and limited in latitude by the Tropic of Cancer in the northern hemisphere, at approximately 23°30' (23.5°) N latitude, and the Tropic of Capricorn in the southern hemisphere at 23°30' (23.5°) S latitude. This region is also referred to as the tropical zone or the torrid zone.
• The word "tropic" comes from the Greek trops, meaning turn, referring to the fact that the sun appears to turn back at the solstices. The Tropic of Capricorn is so named because about 2,000 years ago, when it was named, the sun was entering the constellation Capricornus at the December solstice. In modern times the sun appears in the constellation Sagittarius at this time. Likewise, the Tropic of Cancer is so called because when it was named the sun was in the constellation of Cancer at the June solstice, whereas it is now in the constellation of Taurus at the June solstice.
• The term "Torrid Zone" originates from the Greek philosopher Aristotle (384 BCE – 322 BCE), who believed the world to be divided into three parts: The "Frigid Zone", close to the polar regions, the "Torrid Zone" (now generally called the tropics), which he considered too hot for habitation, and the "Temperate Zone" between the two, which he considered the best place to be.
• Eighty-eight nations lie wholly within the tropics, and another 20 are partially tropical. Most are developing countries.
• One-third of the world's land surface is in the tropics, and about 1.7 billion people inhabit the area (about 1/3 of the world's population); but poor soil and topographical irregularities make it difficult to support this dense (and growing) population.
• It is estimated that seventeen thousand species of plants and animals are made extinct through logging and other human activities every year. That is two species an hour. Many of these are in the tropics.

Filed under Places, Cultures & Identities

This "beyond the book article" relates to Tales from the Torrid Zone. It originally ran in May 2007 and has been updated for the February 2008 paperback edition. Go to magazine.