If you’re on the beach, this map shows you what’s across the ocean | Hacker News Reader

If you’re on the beach, this map shows you what’s across the ocean

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34 pointsfur0n26 comments

It would be cooler if it took the shape of the beach into account, and showed what would be across the ocean if you were oriented along the tangent line.

That would be difficult, since coastlines are essentially fractal.

Of course, in practice such an app would not attempt inspect the coastline on a molecular level. It would just use vector data from some map source, and I suspect that would work quite well in practice.

Relevant Wiki: http://en.wikipedia.org/wiki/Coastline_paradox

This makes it much easier to relate climate for overseas countries. Ocean currents and other effects excluded, the weather in Japan can be similar to California. Another example, Cuba is directly aligned with Western Sahara.

Meaning Chile is the only country in the world that completely "owns" a latitude. Cool..

Denmark at the top as well.

This is a nice visualisation too (linked from that page).

https://www.jasondavies.com/maps/voronoi/airports/

That's not Denmark (Greenland) at the top. Greenland has been removed from the map for some reason.

If you don't count small islands like South Georgia and the South Sandwich Islands (UK), this seems to be the case in reality. However, it wouldn't necessarily follow from this map, since this map only shows North America.

Another commenter claims Denmark (Greenland) also owns a latitude.

Suggests a project for someone to make a little play app which lets you stand on a beach, aim your phone and discover the next landmass in a given direction.

Or likewise, "looking" down through the Earth. What's on the opposite site of where I'm standing right now (including detailing the oceans and seas).

Here are two sites which show you the opposite points (antipodes) of the earth of a given location. One is interactive, the other takes an address.

http://www.freemaptools.com/tunnel-to-other-side-of-the-eart...

http://www.antipodr.com/

There do seem to be some phone apps available as well.

I was expecting some kind of augmented reality app I could use on the beach to see what's beyond the horizon.

Wow, so Chile has a spot where you can go around the globe and end up back in Chile...that is cool.

For one definition of "around the globe," yes.

This really shows just how "landlocked" [1] the People's Republic of China is by the chain of islands bordering it -- they have less ocean-facing coastline than Morocco, Portugal, and even Mauritania. Next time you read about the PRC (a) trying to assert naval power in the South China Sea, or (b) maintaining claims to Taiwan despite having never controlled it, think of this map and the near complete absence of the PRC on it. Access to the Pacific Ocean is critical to their strategic growth.

edit: [1] see grandchild comment

"Landlocked" is stretching it. It's >800 miles from Kagoshima to Taipei, >300mi from Kaohsiung to Laoag, and ~680mi from Laoag to Hainan. Add in the Tsushima Straits and the bit between Hainan and Vietnam, and that's over 2000 mi of ocean that you'd need to blockade to block China from the Pacific.

Perhaps, if we're arguing word choice, but the broader point is that no megapower wants to play Red Rover for easy access to an ocean if war broke out. Until we develop space-based weapons platforms and/or hypersonic missiles, naval power will remain the key means of projecting power and buffering coastline vulnerability.

As long as naval power remains so important, unquestionable access to nearby bodies of water will be primary objects of power projection.

I think that the choice of projection works against China here, since it has more southerly exposed coastline. Also, much of its exposure isn't due-east. I bet a projection with less polar distortion and some sort of tangent-based algorithm would paint a more accurate picture.

But all that said, there definitely are a lot of islands between China and the Pacific.

this seems wrong to me. If you look at a map, China has a fair amount of coastline.

Do I have this wrong?

The PRC is almost completely surrounded at sea by other island nations which form a near complete "archipelago landlock" that doesn't exist (as far as I know) anywhere else in the world.

So while it is true that China has lots of coastline, it can't project that coastline out into the Pacific Ocean because it is blocked. News reporting about China's actions often misses this important motivator.

What about Hawaii?

somebody doesn't know squat about map projections...

care to explain?

The above poster is mistaking the "rule" that only the Mercator projection allows for straight lines to represent the meridians and parallels of the map. While this is true for both longitude and latitude on Mercator, only longitudes are allowed to be straight on pseudocylindrical projections (like the one shown in the OP). Since the map in the OP only draws along horizontal lines it's fine to use that type of projection.

Cylindrical (Mercator): https://en.wikipedia.org/wiki/File:Mercator_projection_SW.jp...

Pseudocylindrical (Wagner): https://en.wikipedia.org/wiki/File:Wagner_VI_projection_SW.j...

I do indeed stand corrected. The projection wasn't stated and I presumed too much without really inspecting it.

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