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Depperoni
05-01-2012, 10:16 PM
Hello everyone! :)

This is the world I've been working on for some time now. I have tilted the existing Earth 30 and redrew the grid in google earth and then the coast lines onto Joshua's Usable Mollweide Projection Grid. I drew Greenland and Antarctica from deglaciated maps for better reconstruction.

44422

The next step is to add elevation both terrestial and marine. After that persistent winds and ocean currents to reconstruct biozones.
I am mostly interested in learning about physical and biological geography and evolution by reconstructing it on this map, but it could set the stage for a good fictional world.

The (still vague) idea I have is to reconstruct the life in this world after a mistery event that both tilted the planet and wiped out most of human kind. The few survivors left in several refuges here and there would spawn both new wild human species and some cultures capable of rebuilding the biosphere faster then has ever happened before after a mass extinction, owing to the human skill of cultivation. By 50 000 to a 100 000 years in the future, with some ups and downs along the way, this population should have the planet up and running again on a level comparable to today or even slightly further (maybe with limited space travel confined to the solar system.)
With this time scale in mind, tectonics would only have advanced the continental drift by 15 km at best, so I have omitted tectonic advancement on purpose. Changes in sea levels, glaciation, rivers, erosion, deposits and human intervention will change the landscape drastically enough.
My current estimates are that this geography will favor greater glaciation, a drop in sea levels and massive deserts, but some regions will still feature rain forests or grassy plains. The new geography of the former Arctic Ocean should lead to enormous fertility, capable of sustaining an impressive marine food web.

I have all ready put some thought into a global evolution involving the descendants of modern human. Eventhough at this time our species may be harmfull to the environment, I also believe we have the abilty to rebuild the world after catastrophy has struck, in unprecedented ways. At least a lot faster than the time it took non-human nature to rebound from the KPg- or PT-events, baring in mind that an extinction event, even on the scale of the PT-event, would leave many tens of thousands of people and their pets, livestock and crops alive world wide. Add human inginuity and you'll have the biosphere up to modern levels in an evolutionary blink of an eye.
This is both the key and the challenge to this scenario. It will be very hard to find the right amount of extinction and hardship to, on one hand, not wipe out life on Earth entirely, yet on the other hand, challenge the descendants of modern humans and affiliated species enough to evolve into something awesome.
If necessary, I could always throw in some magical radiation, that causes awesome mutations instead of cancer, but somehow I'd rather do it the hard way. Involving even low amounts of magic would kinda beat the purpose of an exploratory reconstruction.

Yet, at this point I still have my hands full on the physical geography of this world. Sometimes it feels like to much for one person to handle.
Some examples of things I haven't been able to figure out yet are the ocean currents in the former Indian ocean, especially around India and between Australia and Antarctica. The Tibetan Plateau lying smack on the equator could also have some weird atmospheric effects for which I have nothing to refer to.

So any advice or help is very very welcome. :)

If anyone can tell me how to post a kmz-file on this forum, I'll upload the grid I made in Google-Earth too.

Gidde
05-01-2012, 10:49 PM
Well ... why not make the catastrophe the same thing that tilted the earth in the first place? A big enough meteor might be able to do both ... well, maybe not (as I'm neither geologist nor astrophysicist), but it's plausible enough for fiction imho.

Depperoni
05-02-2012, 05:16 AM
Yeah, I thought about that one too. A flyby of an enormous meteorite maybe, or some other gravitational anomaly. Any impact that would be big enough to tilt the planet this much, would sterilize the surface though.

I'm considering keeping it a mistery all together. This'll allow me to tweak the pattern of extinction a lot easier, omit traces like craters or disrupted orbits and just focus on the reconstruction. I'm looking many tens of thousands of years later anyway and whatever did it, was only a rough plot device. In say 50 000 years even something causing only a gradual change over time could have had this impact. It may actually be a fun challenge to keep the cause open for others to figure out :P

Lunarra
05-02-2012, 06:26 AM
One thing to think about is changes in winds. Not sure though how much it would affect the climat system. An exemple is the wind between the 40th and 50th parallel south (Roaring Forties and Furious Fifties). In your map there is now antartica stopping the "draught".

Depperoni
05-02-2012, 08:37 AM
That is exactly what I'm focussing on now! :)
Indeed the flow surrounding and isolating Antarctica now is interrupted in the Tilted Earth, which could actually result in a more efficient energy transport to the South Pole, thawing this side of the planet.
One thing I'm not sure about is the energy balance around the Southern tip of Africa. As long as the ocean currents can go over it, they may protect Southern Africa against Polar air masses. Turn down the temperature a little bit, the currents get blocked and you might be looking at an African iceage. At the tipping point, you could have a surprising climate in Southern Africa, with warm wet summers and very cold dry winters. In any case, it will make all the difference for Madagascar.

At the same time the former warm Gulf Stream is pressed Southwards by the tilted North American continent, forcing it along a far longer route to Siberia. On one hand it is stuck in the roaring forties, which would result in a stronger current and more severe Westerly storms, stimulating a good marine climate around it on the American and Eurasian continents. On the other hand, by the time it reaches Siberia, it has been in colder lattitudes for so much longer than the actual Gulf Stream, that it might not be as efficient in warming the place up enough for a temperate climate, resulting rather in a subpolar marine climate.

Adding to this, that in the Tilted Earth, the South Pole is mostly marine and the North Pole mostly terrestial, this geography seems to result in a cold Northern hemisphere Vs. a warmer Southern hemisphere. This part of the reconstruction is also very interesting for exploring the thermohaline circulation theory and it's effect on the global climate.

Veldehar
05-02-2012, 09:59 AM
An interesting experiment. I fear you know more than me, so I will just kick back and watch, LOL. The affect currents could be staggering. So many things going on in that map. Can't wait to see more!

Depperoni
05-02-2012, 11:07 AM
:idea: I have an idea! What if I start reconstructing from an iceage, take this as a starting point?

An iceage is common to follow on an apocalyps. This will take away most of the problem of rebounding lands in Greenland and Antarctica. Besides, the glaciers may carve out a cool landscape in Southern Africa and North America.
Once I have the glacial ocean currents and winds designed and have the surviving human and wild life regroup in some refuges, I can look for a positive feedback loop to break the iceage, have another climatic change into a more temperate interglacial as a second survival barrier and see what'll happen from there.
This way I'll have the first several thousand years worked out, add some history, some evolutionary challenges and the actual world (also in an interglacial) as an examplar.

Anywayz, I still have to draw the elevation map, so I'll get to that first :P
Oh I can't wait to start reconstructing the new glaciers.

Depperoni
05-03-2012, 10:50 PM
What a little bit of colour can do:
44467

Gidde
05-04-2012, 11:41 AM
Looking cool!


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Depperoni
05-05-2012, 12:15 PM
Thanks :)
I've almost got the continental shelves ready, so the elevation map is underway...

octopod
05-05-2012, 09:42 PM
Wow. The Baffin/Hudson/Labrador/Arctic ocean will be awesome. :-D But you're in for some serious long-term Arctic glaciation there, especially considering that you're busting up the thermohaline circulation pretty seriously. I assume you worked all this out though.

Surely the Antarctic will even out? It's really lacy there, which I suspect is an effect of using current sea level values; maybe once you apply glaciation it'll look more reasonable.

Have you looked into "inertial interchange true polar wander" as a mechanism? It didn't really happen, probably, but it could! Not sure why it might wipe anyone out though, but I'm sure you could come up with something...

Depperoni
05-06-2012, 09:54 AM
Cool! :D I had never before heard of this IITPW-theory. That could be just the gravitational anomaly I was looking for. Thanks!

About such a mechanism causing a mass extinction, I fear I got more than I bargained for. Shifting the climate bands like that, would kill of lots of plant life (for instance the Russian pinewoods and Congo basin both lying smack in the middle of desert bands,) release lots of carbon, basically resulting in a kind of "clathrate gun," similar to the PT-extinction. Flooding the atmosphere with such massive amounts of carbon, uses up the oxygen, killing even more life, making it possible for free methane to flood the atmosphere, resulting in a run-away greenhouse effect, killing of more life, releasing even more carbon.
Though I may have a safety net: Some of the tropical rainforests, especially the Amazon, are left in place. The carbon left by the clathrate gun actually stimulates plant growth, while the lack of oxygen takes away large herbivores and the danger of wild fires. So the jungles have a field day! Similarly the algeal blooms in the subpolar regions may regenerate quite quickly. So after an initial global suffocation follows a global oxygen injection, reducing the methane and returning everything back to normal.
Just two things:
1: I have no idea how long this mechanism would take to unfold.
2: I have no idea how severe it would be and how it would effect the human species and its domesticates.

(Scary thought: Isn't this clathrate gun exactly what is going on right now in the real world?)

By the way, you're saying this geography will bust up the thermohaline circulation. Could you elaborate that further?
I have a gut feeling you are right, you see, but I'm still unable to rationalize it.

I think I may be able to finish the continental shelves today, so I'll pbb post a new map this evening.

Gidde
05-06-2012, 12:38 PM
I was thinking that a gravitational effect sufficient to wander the axis of rotation by 30 degrees would also set off ticking time bombs like Yellowstone ... which would help in the mass-extinction department.

Depperoni
05-06-2012, 01:54 PM
Absolutely! Globally intensified tectonics, bunch of volcanos going off all at once, earthquakes, land slides and tsunamis all over the place, that would really mess the planet up!
It would also fill the sky with aerosols, blocking sunlight, causing an initial iceage and killing off even more plant life, including algae, in turn causing an anoxic event in the seas as well.

However now we have an iceage followed by a clathrate gun and no forests left to restore the system. That's what I was afraid of.
Climactic cataclysm on this scale would kill about everything. Permo-triassic extinction all over. Only now with chemical toxins, heavy metals and radioactive material left behind unchecked.
I'm not sure I'll have any macroorganisms left to work with, let alone humans. After the original PT-extinction it took trees about 6 million years to reevolve, during which the entire planet was pretty much a giant desert.

If I don't find some way to lighten the burden, I think I'll have a very dead and boring planet.
My bet is still on human domestication and agriculture. Think about it, if we can't even terraform are own planet, we won't stand a chance on other planets.
But changing Earth into a second Mars may just be a bit too much of a challenge.

Alternatively, the early triassic did spawn some interesting clades, like dinosaurs, pterasaurs and ichtiosaurs. At the same time some older clades were still walking, especially the dicynodonts and cynodonts (that would later give rise to modern mammals.)
I could take the time scale to entirely different level and have the humans left behind as the next cynodonts while having all kind a weird new species evolve around them...
This is starting to look more and more like "Nausicaa of the Valley of the Wind"

octopod
05-06-2012, 05:37 PM
Well, a clathrate release only hangs around in the atmosphere for a hundred years or so, since methane's got an atmospheric residence time of something like 15 years IIRC. So that'd be a brief heat boom -- this is the supposed PETM (http://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum) trigger, and that was an incredibly brief blip, less than 100,000 years.

The volcanic release would be more significant, but I'm still not sure it'd be on a Siberian Traps scale. The last few times the Yellowstone hotspot has gone off, it's been well below 5000 cubic km -- enough to cause a volcanic winter and make some large herbivores briefly unhappy, but not enough to register as a blip on the extinction scale. Furthermore it's rhyolitic IIRC so you'd just get a ton of ash, though well enough to make it locally uninhabitable for a while. The Siberian Traps were something on the order of a million cubic km, and basaltic so they all stayed local.

The "nuclear winter" effects of the Chicxulub impact didn't make the angiosperms go extinct -- they did just fine, as did most of the bugs living in them, in fact. The part of North America that got the ashfall would be hosed as far as forests go, that is, but the forests of SE Asia and the Amazon should be alright, and the tropical Australian forests should spread. You've drastically reduced the amount of land in the 30 desert zone, and increased that in the tropical-forest zone. Plus there's a ton of new drowned shelf in the Baffin-Hudson-Arctic ocean area, which should stimulate the ocean ecosystems.

If you're putting yourself 100,000 years after the cataclysm, I think you should be past the clathrate warming, acidification, and volcanic-winter nastiness -- at least if we take the PETM as an example. Or PETM + Long Valley Caldera eruption, for that matter. You'd have to figure out what went extinct, though, and what's taking its place. But I doubt you'd be getting into P-Tr, "everything but the stromatolites is gone" type territory.

Regarding my comment about the thermohaline circulation (http://upload.wikimedia.org/wikipedia/commons/a/a6/Conveyor_belt.svg) (I love that image), you're nuking the very cold meltwater that sinks in the North Atlantic with this as well as breaking the circum-Antarctic current loop...

Depperoni
05-06-2012, 08:08 PM
Hmmm... your analysis is actually quite a relief :)
Honestly I had no idea the clathrate gun would only work for such a short amount of time. So I guess it wouldn't stop a volcanic winter.
Of course globally increased volcanic activity would be a little more of a problem than just Yellow Stone going boom, though I agree with you that it still wouldn't be Siberian Traps scale. Still, the ash being emitted world wide instead of locally, could result in more impact-like winter, maybe making the Chixculub event a better model to work from, albeit in a less severe fashion.

I'll lose most wild large animals, as most are few in number. But as cows, horses, sheep, goats, dogs etc. are just as widely spread as humans, and probably cared after by at least some survivors, I'll have quite some large animals left.
Indeed bugs and other small animals will be doing just fine, as well as many species of birds and of course former pets and pests.

So in this light I guess the early postapocalyptic age will be a lot more like the Fallout universe. But then the planet will be up and running modern style within a mere thousand years or so.
As I learned as a young kid playing SimEarth, the slightest tweaks to a planet can turn it in either a freezer or an oven. Now I'm running into the balance between a brief discomfort and global extermination.
I'm trying to get the human population down to a few million world wide or even less. Then I want to challenge them enough to diversify into new species. Incomplete speciation and stuff like ring species will probably be the norm, as 100 000 years is a bit on the short side for evolution, but who doesn't like hybrids in fantasy :P

Octopod? Do you have any pointers on how to work out a fictional thermohaline system? Because eventhough I've read about the thermohaline circulation several times, the mechanics behind it still baffle me when it comes to a fictional world.
Do polar waters always attract surface waters? And is there a logical way to plot the course of deep sea waters from the poles to upwellings? And most importantly, how can you tell if the system is balanced, whether it stimulates or frustrates heat conduction from the tropics to the poles?

Gidde
05-07-2012, 12:19 AM
Plus, you have to keep in mind that, IIRC, the Chixulub impact's really deadly part was the raining of fire everywhere (a lot of stuff got thrown into sub-orbital space and fell back down as I understand it); I don't think a global winter would be nearly as devastating. You'd lose a lot of the cold-blooded stuff, for the most part. The bigger mammals would actually probably be ok; they have lots of keep-warm mechanisms already.

Depperoni
05-07-2012, 03:37 AM
So no fern spike then. More like a couple of years of darkness and cold, and a bit of volcanic glass splinters tearing open lungs and digestive systems and a bit of acid rain.
Biggest problem for most life is the acute shift of climate zones. And also the complete collapse of human economy/society.
I'll have a better understanding of the scale of destruction when I have my climate zones ready.

octopod
05-07-2012, 11:41 AM
I...actually don't have any general way to work out the circulation, honestly.

The formation of deep water is governed by density, which is a balance between salinity and temperature, both of which are governed by wind-driven surface evaporation. So...
1) Fast wind and freezing temperatures both cause water to become colder and saltier, and therefore to sink; hot rainy climates make it warmer and fresher and therefore less dense. (Hot dry weather and cold rain both have less effect, obviously)
2) The water that sinks to the bottom flows downhill, and flows away from the points where it sinks from the surface; water is "produced" at the rainy tropical latitudes and flows toward the points where it sinks.

I don't know what you can do with this -- I have to go do other science but I'll be back later. :-P

Depperoni
05-07-2012, 12:26 PM
Thanks anyway :)

rdanhenry
05-10-2012, 02:08 AM
I...actually don't have any general way to work out the circulation, honestly.

I'm pretty sure nobody does. I mean, there are computer models, of course, but it's too early to really judge them. There's been a relative explosion of deep-ocean data in recent years, but anything that deals with the deep ocean is still working with limited information and when we are still trying to work from a general to detailed understanding of what actually happens, trying to answer counterfactual scenarios leaves a lot of room for speculation.

Of course, half of "hard" science fiction is recognizing when you're violating known science so you can cover with some technobabble (ideally with something that's at least superficially plausible, like "the water warms here because of extensive underwater vulcanism") or sidestep entirely as so normal in the setting as to be accepted without comment.



The formation of deep water is governed by density, which is a balance between salinity and temperature, both of which are governed by wind-driven surface evaporation. So...
1) Fast wind and freezing temperatures both cause water to become colder and saltier, and therefore to sink; hot rainy climates make it warmer and fresher and therefore less dense. (Hot dry weather and cold rain both have less effect, obviously)
2) The water that sinks to the bottom flows downhill, and flows away from the points where it sinks from the surface; water is "produced" at the rainy tropical latitudes and flows toward the points where it sinks.

I don't know what you can do with this -- I have to go do other science but I'll be back later. :-P

I think a few general rules like this are the best you can do, especially without trying to map out the entire sea floor and run a resource-intensive simulation. We can certainly say that certain proposals would definitely not be at all likely, so the rules can keep from creating something implausible, but I think there's still going to be a lot of wiggle room to assume things flow in ways that are productive of the situations desired by the author.

octopod
05-14-2012, 12:24 AM
Well, of course we don't have a complete general circulation model yet, but I've got the impression that the GCMs we do have are good enough to predict the major features of world ocean circulation. But really that's immaterial, unless Depperoni is willing to run GCMs of this world on some computer cluster or another, lol. :)

Really, I was mostly hoping someone on here who's the right kind of geoscientist could step in and give better guidelines than I could come up with off the top of my head. Surely there are plenty of other geo types on a site like this, right?

Depperoni
05-20-2012, 02:27 PM
Pfew... finally got my continental margins, everything down to 500 meters:
44959
Good marine elevation maps of Antarctica are so scarce, I had to use my imagination as well, but the rest is pretty acurate.
I suddenly have a job and a well filled agenda, so I won't be posting as much as I thought I would :P
Rest of the topography is coming up (don't know when though....)

Depperoni
05-20-2012, 02:48 PM
woops, I just found out I forgot some part West of Florida
44962
corrected

lajosb
05-21-2012, 08:42 AM
Have you seen the tilted earth maps here?:
http://www.worlddreambank.org/T/TILT.HTM

Depperoni
05-21-2012, 08:51 AM
Oh wow! That's perfect :D
Thank you a lot!

Depperoni
06-09-2012, 12:04 AM
I've drawn two sketches of air pressure, kinda based on maps of the real world, but pretty intuitively.
The black lines are 1014 hPa
Low pressure runs to 1010 and 1000
high pressure to 1018, 1022, 1026 and 1030

The first one is january
45491

The second one is july
45489

What do you think? Does it look natural? Anything that really doesn't fit?

(Ignore the attached thumbnail, I don't know how to remove it...)