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Definition of Low Latitude

Ancient astronomers knew that the earth is round, a sphere, even though the mariners of the Middle Ages forgot and were sure that the earth was flat. The ancients figured out how to measure the earth's circumference and used that information to create a system of concentric circles to divide the earth into sections. They called the lines defined by these circles lines of latitude. Later geographers assigned upper, middle and lower zones to name the various groups of latitudes. Lower latitudes are closest to the equator.

Geometry
- Hipparchus was an ancient Greek astronomer who lived in around 300 BC. He based his assumption that the earth is a sphere from what he knew of the celestial bodies like the other planets in our solar system. Once convinced that the earth is a sphere, he was able to create a set of rules that describe the geometry of spheres. He is credited with suggesting that a map of the earth could be drawn using a set of grid lines.
Types
- A few years later in around 225 BC, another Greek astronomer, Erosthenes, fairly accurately calculated the distance around the earth at its widest point, the equator. Once the equator was identified, people could assign the parallel lines called latitude according to the angle of the sun's rays. Measuring the sun at noon kept the calculations consistent.
Size
- The number of degrees from the equator to the North Pole of the earth is 90. There are also 90 degrees from the equator to the South Pole. When a line of latitude parallel to the equator is drawn 1 degree from the previous line, the distance between the two lines measures about 60 nautical miles.
Effects
- Latitude zones measure 30 degrees each so there are three latitude zones north of the equator and three latitude zones south of the equator. Since the measurement of the equator is latitude zero degrees, it includes the low latitude zones. The low latitude zones go from 0 to 30 degrees north and south. The middle latitude zones go from 30 to 60 degrees north and south and the high latitude zones go from 60 to 90 degrees north and south.
Geography
- Low latitude zones are characterized by a warmer climate. Parts of the low latitude zones have an equatorial climate. Other areas have tropical or sub-tropical climates. The low latitude zones include wetter areas as well as some desert areas. In the western hemisphere, Mexico, Florida, most of Brazil and most of Africa lie in the low latitude zones. In the eastern hemisphere, all of India, the Arabian Peninsula, Southeast Asia, Indonesia and the northern part of Australia are in the low latitude zones.

Astronomy