CLIMATE

, or Clime, in Geography, a part of the surface of the earth, bounded by two lesser circles parallel to the equator; and of such a breadth, as that the longest day in the parallel nearer the pole exceeds the longest day in that next the equator, by some certain space, as half an hour, or an hour, or a month.

The beginning of a climate, is a parallel circle in which the day is the shortest; and the end of the climate, is that in which the day is the longest. The climates therefore are reckoned from the equator to the pole; and are so many zones or bands, terminated by lines parallel to the equator: though, in strictness, there are several climates, or different degrees of light or temperature, in the breadth of one zone. Each climate only differs from its contiguous ones, in that the longest day in summer is longer or shorter, by half an hour, for instance, in the one place than in the other.

As the climates commence at the equator, at the beginning of the first climate, that is at the equator, the day is just 12 hours long; but at the end of it, or at the beginning of the 2d climate, the longest day is 12 hóurs and a half long; and at the end of the 2d, or beginning of the 3d climate, the longest day is 13 hours long; and so of the rest, as far as the polar circles, where the hour climates terminate, and month climates commence. And as an hour climate is a space comprised between two parallels of the equator, in the first of which the longest day exceeds that in the latter by half an hour; so the month climate is a space contained between two circles parallel to the polar circles, and having its longest day longer or shorter than that of its contiguous one, by a month, or 30 days. But some authors, as Ricciolus, make the longest day of the contiguous climates to differ by half hours, to about the latitude of 45 degrees; then to differ by an hour, or sometimes 2 hours, to the polar circle; and after that by a month each. See tables of climates in Varenius, chap. 25, prop. 13.

The ancients, who confined the climates to what they thought the habitable parts of the earth, reckoned only | seven, the middles of which they made to pass through some remarkable places; as the 1st through Meroe, the 2d through Sienna, the 3d through Alexandria, the 4th through Rhodes, the 5th through Rome, the 6th through Pontus, and the 7th through the mouth of the Borysthenes. But the moderns, who have sailed farther toward the poles, make 30 climates on each side.

Vulgarly the term Climate is bestowed on any country or region differing from another either in respect of the seasons, the quality of the soil, or even the manners of the inhabitants; without any regard to the length of the longest day. Abulfeda, an Arabic author, distinguishes the first kind of climates by the term real climates, and the latter by that of apparent climates.