Needed - a modified map of the Earth

[ffutures]

I've looked at the various options for changing the position of the Earth's axis - see previous posts - and decided that I'm going to go with a relatively small change, moving the North Pole about 15 degrees south along the 180 degree meridian, a little west and north of the Bering strait between Alaska and Siberia. This means that London is now at 35 degrees north, not 50 degrees, so hopefully enjoys a mediterranean climate (about the same as Algiers). The North Polar ice cap is probably going to end up close to or touching Siberia and Alaska, but they're used to cold weather there anyway, while the South Pole moves closer to the tip of Africa, and hopefully nothing too drastic happens to the rest of the world. It's still going to be a more or less recognizable map, just a bit distorted.

Niamey in Niger is now on the equator, I think the northern tip of Australia is too, Ecuador is now very slightly south of it, and so forth. You can visualise this to some extent as a sine wave plotted on a normal map of the Earth, with the peaks 15 degrees North of the current equator at the Greenwich Meridian, 15 degrees south at 180 degrees.

The snag is that what I will need is a map of the earth plotted with the new equator as a straight line, and the land masses shifted accordingly. I can probably fake this to some extent by distorting a normal map, but all map projections lie to some extent about the position and size of land masses near the poles, and changing their position without changing the relative sizes will make this worse. I'm not enough of a geographer to get this right. If anyone has software or the skills to do this properly, or can think of a better way to do it, I'd love to hear from you.

I'm not too sure what to do about the degree of axial tilt. 20 degrees or so seems to work well for having seasons and forming nice big ice caps, but would anyone stupid enough to do this in the first place think of that?

Comments

[keristor.livejournal.com]

I was going to ask about the axial tilt. Too small and you get less severe seasons, but on the other hand the north and south are permanently cold (at the current latitude of Scotland, for instance, it would be permanantly like March and not very habitable) and the tropics are wider. Too large and the Arctic and Antarctic Circles move towards the equator, giving warmer summers (more area direct sunlight but colder winters. 20-25 degrees seems a good compromise.

(This is something a lot of SF, and especially visual media SF, gets wrong, with "desert planets" and "forest planets" and the like. You can't have a planet which only has one sort of terrain except in very unusual conditions, like being in a close orbit round a cool star where the solar orbit time is on the same order as the rotation of the planet and with high axial tilt, and in that situation any concept of 'day' and 'night' would be definitely strange. It's dubious if such a planet would be very colonisable. But I digress...)

As for the map, it sounds as though you want a Mercator or similar projection with your altered poles and equator. What you need, therefore, is a 'map' being a full spherical list of coordinates, rotate those (simple trig, just tedious), and then re-project (again, simple trig). The big problem is getting that map in the first place (note that you need the solid ground, having removed the icecaps, then you replace those afterwards).

If someone has such coordinate map, I would be /very/ interested in getting such a list. The alternative, as you say, is to try to reverse engineer them from a standard projection but you'll lose details round the poles.

(Hmm, the BBC must have such a map, for the rotating Earth graphic which they have sometimes morphed into a tumbling cube etc. Possibly not much detail, though.)

Note that the Arctic cap will have become largely open sea on the Atlantic side, and possibly down to Japan on the other side.

[pbristow.livejournal.com]

"The alternative, as you say, is to try to reverse engineer them from a standard projection but you'll lose details round the poles."

I tend to think of the poles as not really *having* details. Unless you count the penguins... =;o}

[keristor.livejournal.com]

Exactly, because they are covered with ice most of the time no one is bothered that (like Greenland on most maps) they are just a white blob. But with the shift in axis the existing poles will be significantly down and Antarcica at least will be partially ice-free. Which then raises the question about wher the actual land boundary is in that area.

[pbristow.livejournal.com]

Indeed. And Antarctica is already a hotly(ironic?)-contested continent.

All we need now is for some Krynoid (http://www.google.co.uk/search?q=krynoid&hl=en&biw=1680&bih=890&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=bHVlTunzGpOp8AOWnZiJCg&sqi=2&ved=0CDcQsAQ) or other to throw the cat amongst the lemmings...

=:o}

[nelc.livejournal.com]

I think what I'd do is get a cheap globe from somewhere (Early Learning Centre, maybe) and redraw the equator, major lines of latitude and poles on it in marker, then make illustrations from that. Or photocopy one of the 'peeled-orange' equal area projections from an atlas, cut out and assemble as a sphere, and do the same. Alternatively, do it in a 3D package with a free globe.

I've been trying to think how to do it with maps and the polar projection filter in Photoshop, but I can't quite visualise it. Take a map of the globe, convert to polar co-ords, displace by eye, then convert to Cartesian. Might work, but going from Mercator is going to leave a pair of holes over the poles, plus I don't think Mercator is the right projection to use.

[nelc.livejournal.com]

Ah, that wasn't as hard as I imagined it would be. Can you see this:

(http://smg.photobucket.com/albums/v176/Nelsie/Sci-fi/?action=view&current=world_map-15-displaced-50.png)

If not, try this (http://img.photobucket.com/albums/v176/Nelsie/Sci-fi/world_map-15-displaced-50.png).

Not print-worthy, but you should be able to use it as a basis for tracing a map of your own. The bold lines are the new equator, 30° and 60° latitude lines. The old lines are still there but warped, so you can see where the temperature won't have changed very much. Looks like North America and East Asia aren't too badly off. Nova Scotia and New York will enjoy a balmier climate, while the West Coast will be getting a little cooler. Texas might become marginally less habitable, as will Alaska, for opposite reasons.

New South Wales may get a bit dryer, while northern Queensland looks to become even more unbearable. Japan will be cooler too, and Hawaii.

Contrary to what I posted last time, it looks like the Sahara and Kalihari will be moving north, reducing the habitability of the north African coast and maybe Spain, Italy and Turkey, but making South Africa a bit more temperate.

Looks like the Ross Ice Shelf will disappear, while the Ronne Shelf will be growing, and Wilkes Land might become slightly habitable.

[ffutures.livejournal.com]

Fantastic, that's exactly what I want, and I can delete the curved lines easily enough. Given how small it will be on the page I think it will be fine.

Many many thanks!

[ffutures.livejournal.com]

Sorry, I forgot to say, if you could remind me of your name (and don't mind doing so) I'll give you a credit in the acknowledgements.

[nelc.livejournal.com]

Nelson Cunnington, but NelC is fine, too.

[ffutures.livejournal.com]

Forgot to say that I'll leave the old lines in to show where the parallels used to be.

[pbristow.livejournal.com]

"Contrary to what I posted last time, it looks like the Sahara and Kalihari will be moving north"
Do you mean the geographical areas we now know by those names will move north, or that the *phenomena* (i.e. the actual deserts) will move north?

Parts of the Sahara are due south of Britain (an irony I noted after travelling to the Sahel via Moscow!), so if you move Britain closer to the equator then you move "The Sahara" - as currently labelled on maps - south too (as your diagram shows)... but then the Sahara (the actual desert) will start creeping northwards towards Spain.

I expect there to be an awful lot of very (literally) hot-headed Spaniards and Italians coming over here, to escape the heat and have their touristy revenge upon us. So no change there then. =:o}

[nelc.livejournal.com]

As phenomena. Clearly, nearly every geographic feature at 0° longitude will be moving south, as most of the stuff (what little there is) at 180° will be moving north. But the deserts form at around 30° north and south of the equator, due to the Hadley cells formed by coriolis forces on the spinning Earth's atmosphere. So everything else being equal, the African deserts will be marching north of their present geographical position.

A 15° shift isn't too drastic a move, so I'm thinking that there won't be too much shifting of long range wind and ocean currents, relative to geographical features, though I could be wrong. My feeling is the the circumpolar current around Antartica won't change course, for example, though it might weaken or waver in certain places. I think the Gulf Stream will still be being generated, though it probably won't be pointed at the British Isles any more. But I could be wrong, and Marcus doesn't care anyway. ;)

[nelc.livejournal.com]

How big in pixels would you need it to be?

[doc-mystery.livejournal.com]

After a bit of searching (since I remembered someone else doing this), here's this link which may help you:

http://www.worlddreambank.org/T/TILT.HTM

::B::

[ffutures.livejournal.com]

Thanks - they're interesting, but it looks like nelc has done all the work for me.

[dandello.livejournal.com]

My one concern is the Icecaps - shifting those it may create unexpected changes in the ocean currents which will, in turn, create other climate changes.

[ffutures.livejournal.com]

Of course they will - and little things like the icecaps no longer being centred on the poles will have a big effect, especially in the first few decades after the change. But I'm going to have to mention it without many details, the whole thing derives from one paragraph in the book and is never mentioned again.

[dandello.livejournal.com]

Ah, vagueness *grin* the bane and blessing of all writers.

[whswhs.livejournal.com]

I don't think he offers tools such as you need, but you might like to take a look at Planetocopia (http://www.worlddreambank.org/P/PLANETS.HTM) for some ideas along the same lines.

[ffutures.livejournal.com]

I did - many thanks!

Late, but ...

[history-monk.livejournal.com]

How is the pole shift actually being accomplished? There's, well, quite a lot of momentum that needs to be changed.

Verne's The Conquest of the North Pole has a description of what would happen if it were done with a single blow, which can be summarised as "quite a bit like a big enough asteroid impact to do the job". The earthquakes and tidal waves would be far beyond anything that happens when the planet is left to itself.

Re: Late, but ...

[ffutures.livejournal.com]

I'm about to post the text, which is my best guess as to how it could be done using the technology described - take it with a pinch of salt though...

Re: Late, but ...

[pbristow.livejournal.com]

The way I figure it, it needs to be done gradually over the course of a year, so that the rest of the world (a) doesn't immediately notice, and (b) when they do notice, assume it's some as-yet unrecognised natural phenomenon.

Also: Changing the orientation of a (near-)sphere of rock is relatively easy: Just fix a pair of rocket engines to a pair of relatively stationary antipodes (such as the rarely visited, fairly unobserved polar regions, for example), and set them firing in the required (opposing) directions for a sufficient length of time... Or period of time each day...

Changing the planet's axis of *angular momentum*, on the other hand... Sheesh! Where do we find a roughly Earth-sized amount of mass we can chuck in the opposite angular direction... without anyone noticing!?! =8o>