Mercator projections

Example of two projections. Panel A shows a Mercator projection Panel B shows an interrupted flat polar quartic equal-area projection. 

The route taken by President Gerald Ford from Washington, D.C., to Tokyo, Japan, via Fairbanks, Alaska. Panel A shows the route on a Mercator projection Panel B shows the route as a great circle. Adapted from Muehrcke and Muehrcke (1998, 526). 

Mercator projection (Gerardus Mercator) The Mercator projection maps the Earth s surface onto a series of north/south cylinders. 

As the skewed section is a loxodrome, i.e. a path over Planet Earth under constant compass direction, it is well known that the length of this section equals / sin(/). As to the length of the parallel section, consider the mercator projection of Planet Earth. It is well known that on this projection the projected distance of the -parallel to the equator equals gconformal mapping of Planet Earth s surface, i.e. it preserves angles, and that it also preserves distances... 

Except for the Arctic and Antarctic regions, the Mercator projection is routinely used. The coordinates are shown by a code keyed at the end of the map but, as we have already seen, it is rare for them to be correctly placed. Empirical methods enable the parallels and meridians to be placed fairly correctly a correction table is given at the end of Appendix D. 

For a Mercator projection on the 1 1000000 scale, on the paper used for IBM printout... 

Denis Cosgrove, The Measure of America, in James Corner and Alex S. Mac Lean, eds.. Taking Measures Across the American Landscape (New Haven Yale University Press, 1996), p. 4. Mercator maps had, of course, accustomed people to the projection of vast, miniaturized landscapes on a flat plane. 

We have determined the relative locations of nuclear lamins and chromatin in the nuclear periphery in a more quantitative manner (Fig. 11) (Paddy et al, 1990). After converting the coordinate system of chromatin and antilamin data sets into a form more appropriate for describing features relative to a surface (the image intensity in the nuclear periphery is unfolded and flattened in a manner analogous to a Mercator map projection) [see Fig. 7 in Paddy et al (1990) and Fig. 1 in Paddy et al (1992)], we then determined the position of closest approach of individual chromatin fibers to the nuclear periphery. The distance between 93 such chromatin fibers in three nuclei and the nearest feature... 

The three basic types of cylindrical projection are the simple cylindrical, the equal-area, and Mercator s projections. A modified equal-area form of cylindrical projection was invented in 1973 by the German historian Arno Peters - and is known as the Peters projection, it draws attention to Third World countries, which are prominently placed in the centre of the map. Landforms close to the equator are elongated, while those in high lattitudes are compressed. 

H) Map projection Mercator only or, for polar regions, polar stereographic projection. 

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