What does topography mean?
Topography is the study of shape and features on the surface of the Earth. These features typically include natural formations such as mountains, rivers, lakes, and valleys, forests, glaciers etc. Manmade features such as roads, dams, and cities may also be included.
Where does the word topography originate from?
Topography is a combination of two Greek words ‘topos’ meaning ‘place’ and ‘graphein’ meaning ‘to write.’ It is extremely important to chart and predict weathers, lay roads and plan other transportation means, to plan architectural constructions, study geology, farming, water body management etc.
What is a topographical map?
Mapping is a crucial part of earth science and are wonderful tools that help us find our way in a street, in a city, in a country, in fact, anywhere on the Earth. There are some maps that show different physical features of the Earth. These maps are called topographic maps. Topographic maps use a particular type of line, known as a contour line, to depict different elevations on a map.
How is information collected to make topographic maps?
There are mainly two primary methods of surveying the landforms – direct survey and indirect survey.
Direct survey –
A direct survey is when a topographer on ground, uses surveying equipment, to measure the location and elevation of the land. Have you ever seen a surveyor along the road sometime taking measurements with the help of a leveling instrument placed on a tripod? They are doing just that!
Indirect survey –
Remote or inaccessible areas on the Earth may be mapped using indirect methods. These methods include satellite images, images taken from aeroplanes, helicopters, radar, and sonar (underwater).
Topographical maps include five categories of elements as following:
- Toponymy which includes names of places, water bodies and highways
- Vegetation including wooded and non-wooded areas
- Reliefs including mountains, hills, valleys and plateaus
- Waters, including oceans, lakes, rivers and stream
- Culture establishments such as cities, railroads and power lines
How are different topographical features highlighted on the map?
Different colors are used in topographic maps,
- Black shows buildings, railroads, power lines and geographical elements
- Red shows transportation routes
- Orange shows unconstructed roads
- Brown is used for elevation
- Green shows forested areas
- Blue is used to depict different water bodies