Page 89 - 4670
P. 89
elongated from north to south, shape is correspondingly distorted at
that location on the map. The same goes for east–west stretching or
oblique stretching. On a conformal map, the indicatrices are all
circles, but they vary in size. On an equal area projection,
the indicatrices have varying ellipticity, but the same area.
The Mercator projection is
conformal. All indicatrices are
circles; area distortion varies
with latitude.
The Sinusoidal projection
preserves area. All indicatrices
enclose the same area.; shapes
are obliquely distorted.
The Equal-Area Cylindrical
projection also preserves area.
Shapes are distorted from north
to south in middle latitudes and
from east to west in extreme
latitudes.
In the Robinson projection,
neither shape nor area is
perfectly right anywhere. Both
properties are nearly right in
middle latitudes.
Figure 6.5. Tissot indicatrices for four projections
VI. INDIVIDUAL WORK
Task 1. Find the sentences in the text which best charactrerize
the Mercator Projection.
The Mercator Projection
One of the best known map projections, the Mercator projection
was devised specifically as an aid to navigation. A ship’s course can
89
