The terms “altitude” and “elevation” are often used interchangeably in everyday conversation, yet they carry distinct meanings within scientific and geographical contexts. While both describe vertical distance, their specific applications and reference points differ. Understanding these differences is helpful for accurately describing locations and positions, whether on Earth’s surface or above it.
Understanding Altitude
Altitude refers to the vertical distance of an object or point above a defined reference level, most commonly mean sea level (MSL). MSL is the average height of the ocean’s surface over a long period. In aviation, altitude describes how high an aircraft or satellite is above the Earth; for instance, planes cruise at altitudes of several kilometers. Aviation uses specific types of altitude, such as “true altitude,” which is an aircraft’s actual height above MSL, and “absolute altitude,” which measures vertical distance above the ground directly beneath it. Pilots rely on these measurements for navigation and safe separation.
Understanding Elevation
Elevation describes the vertical distance of a specific point on the Earth’s solid surface relative to a fixed reference point, usually mean sea level. This term applies to geographical features like mountains, valleys, cities, or any point on the land itself. For example, Mount Everest has a specific elevation.
Elevation is used in cartography and topography to create detailed maps. Topographic maps use contour lines to illustrate changes in elevation, visualizing terrain shape and slope. Surveyors and geologists measure elevation to understand landforms and drainage patterns.
Distinguishing Altitude from Elevation
While both altitude and elevation measure vertical distance from a reference point, their primary distinction lies in what they describe. Altitude generally pertains to objects above the Earth’s surface, such as flying aircraft, balloons, or a bird in flight. When discussing an airplane’s height, “altitude” is appropriate.
Conversely, elevation specifically refers to points on the Earth’s solid surface, applying to the height of a mountain peak, a city, or any landform. For example, a town’s sign might state its elevation. Therefore, a mountain has an elevation, but a climber on that mountain is at a certain altitude relative to sea level or the ground.
The terms can appear interchangeable in casual use, especially when referring to land height. However, in precise scientific and geographical contexts, the distinction is maintained. Altitude relates to how high something is, often dynamic and measured from various reference points. Elevation defines how high a fixed point is on the Earth’s crust, almost exclusively referenced to mean sea level.