Cylindrical Equal Area Projection is a non-perspective projection developed by Lambert (1772). In this projection, a simple circular cylinder is supposed to touch the generating globe along a selected parallel, called the standard parallel. Parallels are projected as concentric arcs of circles with varying radii. Meridians are projected as straight lines radiating from the vertex of the cone and truly spaced on the standard parallel. The principle is that the area of a segment on projection is made exactly identical to the corresponding area on the generating globe to retain the property of equal area.

**THEORY:**

- Radius of the generating globe, R = Actual radius of the earth ÷ Denominator of the R.F.
- Radius of the standard parallel (ø
_{0}), r_{0}= Rcotø_{0.}

**PROPERTIES:**

- It is a non-perspective projection.
- The pole is represented by an arc of circle.
- The tangential scale is true only along the standard parallel.
- The tangential scale increase gradually away from the standard parallel toward the pole.
- The radial scale decreases gradually away from the standard parallel toward the pole.
- Inter parallel distance gradually decrease toward pole.
- It is an equal area projection.
- It is suitable for showing the distribution of any element in the mid-latitude countries or region.

**EXAMPLE:1**

**Draw the graticules of cylindrical equal area projection for the extension of 20**^{o}**W-60**^{o}**W & 40**^{o}**N-40**^{o}**S at an interval of 10**^{o}** on a scale of 1:75,000,000**

**Solve: Calculation Part**

** STEP-1:** Radius of the reduced earth:

R= 640,000,000/75,000,000cm

=8.53cm

**STEP-2:** Division along the equator for spacing the meridians:

d= (2πR × interval) ÷ 360⁰

=1.49cm

**STEP-3: **Distance of the parallel from the equator=R sinϴ

ϴ (N/S) | R(cm) | R sinϴ(in cm) |

10 | 8.53 | 1.48 |

20 | 8.53 | 2.92 |

30 | 8.53 | 4.27 |

40 | 8.53 | 5.48 |

**Exercise: 1**

Draw the graticules of cylindrical equal-area projection for the extension of 4^{o}N-52^{o}N and 24^{o}W -40^{o}E at an interval of 8; R.F.-1:50×10^{6.}

**Exercise: 2**

Draw the graticules of cylindrical equal-area projection for the extension of 16oS-52oN and 140oW -140oE at an interval of 8; Where the length of the meridian for the extension is 14cm. Calculate the R.F. also.

## Join the Community

Join the free community of QGEO where we will be guiding you through the journey of learning geography. We have successfully organized more the 15 online courses. There are more than 2000 students, who actively participate with us. We are providing geography students, scholars, and professionals a better experience in the field of geography.