eli5: Why world map on google is distorted when completely zoomed out (near pole area being spread and near equator being squeezed) but not when zoomed in?

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Is it because the distortion isn’t visible at minute scale? I am of the opinion that distortion should be observable enough even when zoomed out as we go towards poles.

In: Earth Science
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They are using a map projection called Mercator which became famous because it was good for navigation, but it really distorts land masses, they get more distorted as you go farther from the equator, however they try to reduce the error by switching to less distorted maps as you zoom in

On google maps for computers they have decided to switch to actually showing a round earth, removing the problem of distortion, however to save battery in smartphones, it’s easier to just use a flat map

Any attempt to take the surface of a 3D sphere and turn it into a flat 2D map will result in some amount of distortion.

You can only chose which distortion you want but never completely avoid it.

Google maps uses a type of projection traditionally used for maps used for navigation that preserves direction. North is the same direction anywhere on the map.

This is something that works well close to the equator or on a small scale but not well on a world map near the poles.

In a map of your city all roads that are north-south oriented will look parallel and to a person wandering around in the city this will also seem true.

On a large scale map showing the entire world having arrows pointing north be parallel will look somewhat strange as those arrows would actually point to a single point at the north pole.

It is much easier to pretend that the world is flat on a small city scale than on a continent scale.

There is no easy way to fix this short of using a globe or a curved screen.

Some people will bring ideas of social justice into this and say that a different type of map projection would be more accurate, but those people don’t know what they are talking about. There is no way to make a completely accurate map without distortions.

It’s impossible to have a 2D projection of a 3D globe without cutting or distorting it in some way. Most maps choose distortion.

This has the effect of making places nearer the equator look smaller and regions near the poles look bigger.

As you said, the effect isn’t visible on a local scale, it’s basically only on the scale of continents that it’s big enough to be noticeable.

[here’s a good video about map projections](https://www.youtube.com/watch?v=jtBV3GgQLg8)