Cylindrical projection
Topic: Map Projections · NCERT: Class 11, Ch 4 "Map Projections"
Meaning
A cylindrical projection is made by wrapping a paper cylinder round the globe, usually touching it at the equator. The graticule is projected onto the cylinder, which is then cut open and laid flat. Parallels and meridians appear as straight lines crossing at right angles. Every parallel becomes as long as the equator, so distortion grows towards the poles. It works best for the tropics and for maps of the whole world.
Example
The cylindrical equal area projection (Lambert, 1772) is used for maps of the belt between 45°N and 45°S. A typical use is mapping tropical crops such as tea in Assam, rice, coffee, rubber and sugarcane. Mercator's projection is another cylindrical projection, used for navigation charts.
Don't confuse with
- Transverse Mercator: here the cylinder is turned on its side so that it touches the globe along a meridian, not the equator. UTM is built on it.
Related concepts
- Developable surface
- Non-developable surface
- Conical projection
- Zenithal projection
- Normal projection
- Oblique projection
- Polar projection