Size mat­ters

Australian Geographic - - Geo buzz -

IT’S IM­POS­SI­BLE TO ‘project’ a flat map that pre­serves the shapes, an­gles and ar­eas seen on a globe. Car­tog­ra­phers must choose which of th­ese prop­er­ties are most im­por­tant for any par­tic­u­lar pro­jec­tion. Nav­i­ga­tional charts, for ex­am­ple, pre­fer pro­jec­tions that pre­serve an­gles and shapes be­cause this makes it eas­ier to iden­tify routes. An ex­am­ple is the pro­jec­tion of 16th-cen­tury Flem­ish globe­maker Ger­ar­dus Mer­ca­tor, which be­came the stan­dard for world wall maps dis­play­ing con­ti­nen­tal land masses – and is still the most widely used to­day. Un­for­tu­nately, al­though com­par­a­tive ar­eas on a Mer­ca­tor Pro­jec­tion are rea­son­ably ac­cu­rate in equa­to­rial re­gions, they are less so to­wards the poles.The re­sult is wide­spread con­fu­sion about com­par­a­tive sizes of some coun­tries. Green­land on a Mer­ca­tor map, for ex­am­ple, looks about the same size as Africa but you could, in fact, fit 14 Green­land-sized coun­tries into the area cov­ered by the African con­ti­nent.

A truer com­par­i­son of rel­a­tive coun­try sizes re­quires an ‘equal-area map pro­jec­tion’.The il­lus­tra­tion above has been cre­ated us­ing the Lam­bert az­imuthal equal-area pro­jec­tion, which main­tains rel­a­tive sizes of dif­fer­ent coun­tries, with the method­ol­ogy adapted to pre­serve shapes so coun­tries look fa­mil­iar. Us­ing this ap­proach re­veals that most of Europe could fit into Aus­tralia (see above) with room for Ja­pan and New Zealand as well.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.