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Whenever I look at Google Maps at a global or polar area, the projection hurts. Is there any web service with a zoomable world map, that uses an equal-area projection — preferably pseudorectangular such as the Mollweide projection? Even National Geographics online map uses Mercator.

Another alternative, Google Earth, does not particularly distorts the Earth, but does not give a global view either.

See also: Why has Web Mercator (auxiliary sphere) become the web map standard?

Edit 2018-08-24: Google Maps no longer uses Web Mercator, but has moved to what appears to be an orthographic projection.

gerrit
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  • @mapBaker Isn't that exactly what I wrote...? – gerrit Jun 03 '14 at 17:55
  • FYI, If you're seeking an equal-area projection, then Google Earth, which uses a central perspective projection, definitely is distorted. Good Q, otherwise -- something i've often thought to ask. – Martin F Jun 03 '14 at 18:44
  • @martinf I know Google Earth is distorted. It serves a purpose. Canadian Toporama uses a Lambert conformal conical projection, which is much better close the poles, but not equal-area and not very suitable for a global map. – gerrit Jun 03 '14 at 18:50
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    the problem with Mollweide is that the map shows as an ellipse, so that you cannot "go around the world" without interuption. An equal area projection on a rectangular frame (e.g. cylindrical equal area) would be even more distorted. – radouxju Jun 03 '14 at 18:51
  • @radouxju I see. But upon panning, the software could still recalculate the Mollweide with a new center. I see why this is a drawback, and as per the linked question I observe why Mercator is ubiquitous; but perhaps someone somewhere has built something else. – gerrit Jun 03 '14 at 18:59
  • Google/ESRI don't even use the true Mercator projection, they use a Pseudo/Web Mercator projection. This formula is much simpler than the real Mercator, and it's why they can do neat tricks, like pan across the dateline. AFAIK there is no simple Mollweide projection, so asking a web app to constantly recalculate the projection may be asking too much. – Mintx Jun 03 '14 at 19:13
  • @Mintx: Doesn't the "pseudo" just mean the projection is from a sphere rather than an ellipsoid? Also, i did just pan across the dateline in google maps. – Martin F Jun 03 '14 at 19:22
  • Arctic Portal (Equal Area) http://portal.inter-map.com/#mapID=49&groupID=&z=1.8&up=571673.4&left=-680360.0 – Mapperz Jun 03 '14 at 19:30
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    @gerrit what are you trying to do with this web map? If you're looking to simply 'take a look around' because you don't like the 'look' of google maps, why don't you download the Planet.OSM file from Open Street Map, load it into QGIS, and change the projection to one you like? – DPSSpatial_BoycottingGISSE Jun 03 '14 at 19:31
  • Antarctica by ESRI Silverlight Polar Stereographic http://gisdata.usgs.gov/website/antarctic_research_atlas/ http://en.wikipedia.org/wiki/Universal_polar_stereographic_coordinate_system – Mapperz Jun 03 '14 at 19:34
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    @mapBaker I have no specific application in mind. I like to use an interactive map to "explore the world", and I indeed don't like the look of Google Maps. I don't have a lot of GIS knowledge, the process you describe is a bit more wore than simply loading up a website with a easy to use interface... – gerrit Jun 03 '14 at 20:32
  • @martinf Yes, more or less. It applies the spherical Mercator formula to ellipsoidal lat/longs. Spherical Mercator is a different and easier formula than ellipsoidal Mercator. And I stated that you can pan the dateline because they use the easy Mercator formula. (Speculative, can't back this up 100%) – Mintx Jun 03 '14 at 20:40
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    @gerrit added an answer... – DPSSpatial_BoycottingGISSE Jun 03 '14 at 21:13

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Check out this site: earth.nullschool.net when you launch the site, click the 'earth' text, then explore the different projection options... you can pan and zoom on the map too!

Not as detailed, but the implementation of the different projections with the data they're displaying shows a good proof of concept of something you're after I think...

DPSSpatial_BoycottingGISSE
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