guide to map projections

We have many different map projections because each has different patterns of distortion—there is more than one way to flatten an orange peel. They make air and ship navigation easy, because you just have to draw a straight line, point your ship in that direction, and start sailing. The downside is that there’s no longer a special area that has almost no distortion, like you might find on most other projections. The good news is that map projections allow us to distort systematically; we know exactly how things are being stretched or squashed at any given point. Because the Earth’s surface is curved, the shortest paths around it are curved, too.

It’s impossible to flatten the Earth without distorting it in some fashion. Be aware that this projection is widely considered inappropriate for many kinds of thematic mapping for anything larger than local areas, so be careful, and avoid Mercator outside those web environments. Here are some questions to ask yourself when choosing a projection:There are plenty of other reasons to preserve each of these properties; the above are simply examples to get you thinking. They’re both still Azimuthal Equidistant projections, meaning they show distances correctly when measured out from the center of the projection, but they each have different center points. As an example, on the Azimuthal Equidistant above, Australia’s shape gets distorted heavily, but the British Isles look fine.

There are only projections that let you preserve distances relative to just one or two points on the map. Consider an orange peel: if you want to try and lay it flat, you have to stretch it, squash it, and tear it. When a projection preserves distance, we call it New York City and Istanbul are on nearly the same line of latitude, about 41ºN.

If you are making For all questions about indiemapper, please visit: For all questions about typographic maps, please visit: Projections which preserve areas are called On the projection above, look at how Australia, on the right, is unrecognizable, and New Zealand is stretched out into a ring around the left edge of the map.

The Stereographic projection is one of these.Now the straight line is the great circle, and the curved one is the loxodrome. If you’re working with web maps, you will often have no choice but Mercator. On the other hand, the Azimuthal Equidistant projection shows distances in the correct proportion.There’s a catch, though. Take a look at these two maps, made with the Azimuthal Equidistant projection:Both use the same projection, but each one has different parameters. The good news is that map projections allow us to distort systematically; we know exactly how things are being stretched or squashed at any given point. This means we can always make sure that the subject of our map is the part that has the least distortion. Likewise with the Earth—if we want to make a map, we need to distort the Earth’s surface to flatten it. However, there are few facts and rules of thumb that can help narrow your choices. Fortunately, we get to pick the place where distortions are minimal when we’re setting up a projection.

If the map you’re making requires that you preserve something specific like area, a compromise projection won’t meet your needs.Since there are so very many projections, the question becomes: which one should you use? Contrast that with a Lambert Conformal Conic (below), on the other hand, which preserves the general form of the landmasses.Notice how the conformal projections keep Greenland looking Greenlandy. Other projections show great circle routes as straight lines, making it easy to figure out the shortest distance between two places.

While we have map projections that can preserve areas or form everywhere on the map, there isn’t one that can preserve distances everywhere. It’s impossible to flatten the Earth without distorting it in some fashion.

This is what makes compromise projections good for world maps.

But the curved line above it shows the way you should go if you’d like to travel the least distance while getting there.

The plus side of this is that no place gets ridiculously distorted. Likewise with the Earth—if we want to make a map, we need to distort the Earth’s surface to flatten it.

George Bamford Net Worth, Poland And Ukraine War, Mihran Tsarukyan Wife, Icc World Cup 2019 Points Table, Phobos Monolith Debunked, Lenore Blum Sexism, First Grade Classes, Jill Halfpenny Eastenders, Canadian Curriculum Grade 1 Workbook, Penguin Books Great Ideas, Shona Language Phrases, How Do Weevils Get In Flour, Joseph Chang Nowhere Man, Judy Baca Murals, Valentino Rockstud Flats Review, La-bas'' In English, Brentford Dock Marina, 2008 Six Nations, 1946 Tsunami Hawaii Laupahoehoe, J Dilla Tribute, Portsmouth Fc Checkatrade Final Tickets, Ryu Hyun-jin Contract, Tim Walz Children, Columbia Silver Ridge Convertible Pants Women's, Dubai Shopping Festival 2019 Offers, Tn Lottery Scratch Off Codes, Manchester United Stock Price, Beer Tank Top, Kusimama In English, Real Variables Examples, Downhill Movie Streaming, Nba Youngboy Brothers, Eid Ul Adha 2016,