Geog 7 Lab 5 (Week 6)

These maps, the GCS and the Mercator projections, are different in a few different ways.  For one, the distances between Washington D.C. and Kabul on each map are significantly different.  It is 7,000 miles approximately between the two cities on the GCS projection, and about 10,000 miles between them on the Mercator projection.  The Mercator projection distorts distances far more, as the GCS projection is far closer to the actual distance.  The GCS projection also has equal area squares on its map, while the same is not necessarily true for Mercator.  The GCS projection preserves direction, distance, shape and area, which makes it a fairly accurate projection.

A mercator projection is a cylindrical projection.

 The two equal area maps shown are the Sinusoidal projection and the Mollweide Projection.  Sinusoidal projections show size, or area, relatively accurately, but distort shape and direction.  The Mollweide projection preserves area as well, but distorts shape.  The sinusoidal projection looks more horizontally stretched, thereby distorting direction between the land masses.  The Mollweide on the other hand does not seem to distort direction because the relative locations of the continents are kept in check, as it appears to just be like an oval on its side.  Though each 30-30 latitude-longitude square is equal area on each map, they still look different comparatively, which comes naturally with the different manners in which the maps are projected.  Both maps are made using a pseudocylindrical projection.

The two equidistant map projections shown are the Plate Carree projection and the Equidistant Cylindrical projection.  The Plate Carree projection preserves distance and direction, but distorts area, and is also not conformal.  The Equidistant Cylindrical also preserves distance and direction, but also distorts area, and is not conformal.  The features on the maps look different in the sense that equidistant cylindrical map seems to distort area even more so than the plate carree map.  It appears to be more scrunched up, which therefore accounts for its very short estimated distance between Washington, D.C. and Kabul.  The Plate Carree map still distorts area, but seems to make land masses larger, as the estimated distance between Washington, D.C. and Kabul on this map is 10,000 miles.  The Equidistant Cylindrical projection is made using a cylindrical projection.  The Plate Carree map is also made using a cylindrical projection.