Latitude
The angular distance of a location on Earth’s surface, measured in degrees(°), minutes(‘), and seconds(”) north or south of the equator which is defined as 00° (degrees).
Latitude is one of the two primary coordinates used in navigation and cartography to pinpoint a specific location on the Earth’s surface. It is expressed in degrees (°), with values ranging from 0° at the equator to 90° at the poles. Locations north of the equator are designated as having a positive latitude (e.g., 45°N), while locations south of the equator are assigned a negative latitude (e.g., 30°S).
The concept of latitude is based on the Earth’s spherical shape. It represents the angle between a given point on the Earth’s surface and the equatorial plane. The equator itself is the reference line for latitude, dividing the Earth into the Northern and Southern Hemispheres. Each degree of latitude corresponds to 60 Nautical Miles (approximately 111 kilometres or 69 statute miles) of distance on the Earth’s surface. However, this distance can vary slightly due to the Earth’s slight flattening at the poles.
Latitude lines, also known as parallels, run horizontally around the globe parallel to one another. These lines are used with longitude (which measures east-west position) to form a grid system that allows mariners and navigators to determine their exact position on the planet. For example, a location with coordinates of 40°N latitude and 74°W longitude would be found in the northern hemisphere, near New York City.
Understanding latitude is crucial for plotting courses, determining distances, and ensuring safe passage in marine navigation. Historically, mariners used instruments like the sextant to measure the angle of celestial bodies (such as the sun or stars) above the horizon to determine their latitude. Today, modern GPS systems provide precise latitude readings, but the fundamental concept remains the same.
In addition to its navigational importance, latitude plays a key role in determining climate patterns. Regions near the equator (low latitudes) tend to have warmer, tropical climates, while regions closer to the poles (high latitudes) experience colder, polar climates. This is due to the angle at which sunlight strikes the Earth, which varies with latitude.
In summary, latitude is a critical geographic coordinate that helps mariners and navigators determine their position on the Earth’s surface. It also influences climate and environmental conditions worldwide.
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