There are literally thousands of map projections. Each has certain strengths and corresponding weaknesses. Choosing among them is an exercise in values clarification: you have to decide what's important to you.
This one of the oldest and most common projections
The Mollweide Equal Area projection preserves the relative area of landforms.
but it looks like someone hung their laundry out to dry
A great circle path is the shortest path on the surface of a sphere between two points on that sphere.
Ca rto g ra p he rsa ffe c t ho w wep e rc e iveo urwo rld Teacher Lance
Representing the earthA geographical map is a two-dimensional,geometrically accurate representation of a three-dimensionalspace. Inevitably,however,distortion isintroduced whena globe is madeto layflat. This teacher uses a physical map of Europe to explain his point. Teacher Lance
AncientmapClaudiusPtolemy(150 AD)map drawn from Ptolemys coordinates for a1482 edition of his Geographia Teacher Lance
• A map projection isMap any method used inProjection ___________________ (mapmaking) to represent the curved surface of the earth on a flat surface. • This cannot be done without some ___________________ • The mapmaker must select the one best suited to the needs, reducing distortion of the most important Teacher Lance features.
Mapmaker • Mapmakers and mathematicianss have devised almost ________________ ways to project the image of the globe onto paper. • Every projection has its own set of advantages and disadvantages. There is no Teacher Lance “______________"
• Flat maps can be more Good Uses useful than globes in many situations:of Flat Maps • Maps are more compact and easier to store. • They are viewed easily on computer displays. • Maps can show larger portions of the earths surface at once. • These useful traits of Teacher Lance flat maps motivate the development of map
The Problem • Every flat map misrepresents the with Flat surface of the Earth in Maps some way. • No map can rival a _______________in truly representing the surface of the entire Earth • Since the world is a sphere, and a globe is a sphere, a perfect representation can be made. Teacher Lance
Cylindrical Projection: is based on a cylindertangent to the equator. Good for equatorialregions but greatly distorted at high latitudes. Teacher Lance
Mercator projectionThough the Mercator projection is particularlygood for navigation, it becomes increasingly distortedtoward the poles, resulting in areas appearing muchlarger than they actually are. Teacher Lance
• This map makes areasMercatorProjection near the ____________ look bigger than they really are. • Example, Greenland looks bigger than it really is. Here, it is larger than S. America, but in real life, it is less than half the size. • This is because, on a globe, the lines of longitude meet at the poles, but on this type, Teacher Lance
The distortion caused by a Mercator projectionmakes Greenland appear larger than Australiawhen, in fact, it’s one-third its size. Teacher Lance
The Eckert projection tries to keep thecountries in relative proportion but stillflattens out near the poles. Teacher Lance
The Peters projection is an area-accurate map Teacher Lance
• The Peters Peter’s Projection was created inProjection ______________ by Dr. Arno Peters to address some of the distortions of existing maps • Problem: One square inch anywhere on this map represents an equal number of square miles. Distorts the shape in some cases. • Example: Africa Teacher Lance
The Robinson projection is based on tablesof coordinates. The projection distorts shape,area, scale, and distance in an attempt tobalance the errors of projection properties. The Robinson projection Teacher Lance
Robinson • Presented by Dr.Projection Arthur H. Robinson in __________________. • Today, many geographers believe this to be the best world map available. It has been called so by National Geographic • While the Robinson projection does distort the globe a little, (Check out Antarctica), it shows the sizes and shapes Teacher Lance of most countries
• By creatingInterrupted Projection _____________ in the picture of the world, mapmakers showed the size and shape of most of the land quite accurately. • Problems: • The gaps make it impossible to figure distances correctly • You could not use this kind of map to Teacher Lance chart a journey across the ocean.
Conic Projection• Latitude lines are curved on this kind of map. Teacher Lance
PolarThis projection isused by pilots todetermine theshortest routebetween twopoints on theglobe. Teacher Lance
Upside down? Depends on our pre-conceptions Teacher Lance
Differences between map projections Teacher Lance
Prime Meridian:• 0° longitude line that runs from the north pole to the south pole Teacher Lance
Different types of Maps • Political Map: shows location of countries, states, and provinces and boundary lines separation governments • Physical Map: shows physical features of an area • Mountains, plains, valleys, etc • Economic map: can see that locations of natural resources, industrial areas, farmlands, and fishing areas • Travel or transportation map: also known as a road map Teacher Lance
LandsatA series of satellites thatcan photograph theentire earth in 16 days. Teacher Lance
Global Positioning Systems (GPS)This system uses a series of 24 satellites calledthe Navstars to beam information to earth aboutan object and its location of the earth’s surface. Teacher Lance
Atlas technology“Like a huge pieceof orange peel thatrefuses to beflattened withouttearing at theedges, the globecannot be forcedinto twodimensionswithout distortion.But that distortioncan now beminimised “ Teacher Lance
Geographic Information Systems(GIS)A system that uses digital map information tocreate a databank to produce specialized maps. Teacher Lance
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