How would living in or on Pangaea be?

How would it be, what effects would a Pangaea, and also a Panthalassa (the super-ocean) have on modern civilization?

All fields are appreciated (climate, tech, science, agriculture, fishing, transport,...). Maybe we do a TL (although, then, in the ASB forum) with the PoD that Pangaea formed again abruptly on 9/11?
 

whitecrow

Banned
How would it be, what effects would a Pangaea, and also a Panthalassa (the super-ocean) have on modern civilization?

All fields are appreciated (climate, tech, science, agriculture, fishing, transport,...). Maybe we do a TL (although, then, in the ASB forum) with the PoD that Pangaea formed again abruptly on 9/11?
Inland would be a dry, hostile desert. only coastline is habitable.
 
Inland would be a dry, hostile desert. only coastline is habitable.
Just the coastline? There wouldn't be any open plains that could allow rain formed on the ocean to move inland, at least a little bit?

Also, are there still islands, or are these stuck onto Pangaea?
 
Pangea's interior would not be all desert. I can answer some of this, but it depends on if you're assuming humans develop in the Permian Age conditions (the last major Pangea; a very hot time with different Earth tilt) or modern Earth with a pangeaic continent.
 
I assumed 9/11 tilt and climate, but the continent becoming pangeic.

And: Who is willing to do a TL for Evolution on Shiveria, somebody did one for Jaredia already.
 
I always love it when someone posts a good-looking equirectangular world map!

So that top map, the EQ one called 260Marect, are the shades of green and brown, and the limits of glaciation, indicated on it based on lots of cross-referenced paleontological evidence of actual temperature/humidity ranges and actual estimates of plant cover?

Of course any such map, no matter how meticulously worked out, would be impressionistic at best, because the "Pangaea period" from formation to breakup covers many tens of millions of years, while fossils will be few, and scattered, and from that entire range of time at various spots, so it's impossible I guess to come up with anything definitive for any one period.

Anyway, assuming that the map offers us a reasonably representative snapshot of some time or other around 260 million years ago, I've derived a cylindrical equal-area map and set it beside a similar sort of portrayal of modern Earth, also in equal-area projection.
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Looking at them side-to-side like that, it seems that maybe the glaciation on the combined Antarctica/Australia part of southern Pangaea added up to more than the modern areas of Antarctica and Greenland today, so probably in this particular snapshot of time, the sea levels were a bit lower though probably not as low as during our recent glaciations when a lot of North America and Europe had icecaps too. Looking at your other map, it seems that a fair amount of land area we have today was uplifted from continental shelf area by various fairly recent collisions of land masses, so overall Pangaia has somewhat less land area.

I'd think, from their latitudes, that the belts of relatively strong green your EQ map has must have been temperate forests and swamps and the like, not so "tropical" as we tend to think. The desert belts are indeed broad and wide but then again they are pretty bad in our time too. The major omission, relative to our world, is a lack of tropical jungle belts--the main green in the tropics seeming to be the windward side of the great central Pangaean mountain range separating modern Africa and South America from North America and Europe--the range that today is represented by the Appalachians, the highlands of northern Europe I guess, the Atlas ranges and the highlands of northern South America. So although equatorial that belt might have only been getting good rainfall due to high elevation and therefore be cooler than we expect, so yet another "temperate" belt in character if not in variation of seasons.

If the axial tilt of Earth were in the same ballpark as it is today (and I believe conservation of momentum, barring some major collision event--I mean "major" in a way that makes the dinosaur killer 60 million years ago look puny:p!--guarantees that) then the northern and southern temperate belts are at high latitudes compared to modern counterparts for the most part, so their seasons would be very pronounced, I'd guess snowy in winter but pretty balmy in summer.

It's hard to believe that those islands in the middle of the sea would not be tropical and moist so I don't know why they are shown such a dull green.

If all these impressions of mine, based on this picture, are reasonably right, then actually it would seem that Pangaea in this era was at least as rich as our modern world in climates someone acclimated to temperate zones today would like. The big losers of our world transferred to this one, by time machine or sideways shifts to some alternate world, would be people who like tropical moist climates, surprisingly enough! Desert-lovers would indeed be quite well gratified--it seems fair to say this is a world where desert wins out against the jungles and the temperate zones hold their own.

Noting that the temperate zones are along the northern and southern shores of the great world-island, which after all is not one compact mass but sprawls out in peninsulas and is cut nearly in half by bays, it is easier to understand how comfortable niches can exist on a greater scale than we first imagine. The harshness of the great deserts is definitely a big part of the "feel" of Pangaea to be sure! Still, if graduations of shade in the offered map indicate anything significant it would seem that even the great equatorial central desert has large regions of dry savannah in the east.

ComparedCylindEqArea.jpg
 
If the axial tilt of Earth were in the same ballpark as it is today (and I believe conservation of momentum, barring some major collision event--I mean "major" in a way that makes the dinosaur killer 60 million years ago look puny:p!--guarantees that) then the northern and southern temperate belts are at high latitudes compared to modern counterparts for the most part, so their seasons would be very pronounced, I'd guess snowy in winter but pretty balmy in summer.

"Wandering" of axial tilt is a bit funny--it is quite possible for an entire planet's axial tilt to vary quite dramatically (eg., Mars). Since the Moon has had a significant effect on Earth's axial tilt, I would expect that what would happen (since the Moon would be closer and therefore exercising a higher influence on Earth) would be that axial tilt variations would be somewhat more limited than today, and possibly the axial tilt itself would have a different magnitude (but I'm not sure about that).
 
"Wandering" of axial tilt is a bit funny--it is quite possible for an entire planet's axial tilt to vary quite dramatically (eg., Mars).

Right, I guess perturbation and tidal interactions with Jupiter and the Sun can transfer components of angular momentum somehow, though I am not sure how that can work with the component at right angles to the main axis of the system plane of the ecliptic. But if it happened to Mars, with no big moon, I guess it can happen anywhere! Mars is pretty close to Jupiter though.

Big meteor/comet impacts can also have a significant effect on the total spin vector, or so I gather from that impact effects calculator that I can't remember the link to or name of now. Perhaps the dinosaur-killer did change the tilt somewhat after all? The masses involved are relatively small (unless they are so large we are talking about melting the crust and splashing out enough mass to make Luna!:eek:) but they come in fast and if the angle is glancing, the angular momentum imparted can be significant I guess.

Since the Moon has had a significant effect on Earth's axial tilt, I would expect that what would happen (since the Moon would be closer and therefore exercising a higher influence on Earth) would be that axial tilt variations would be somewhat more limited than today, and possibly the axial tilt itself would have a different magnitude (but I'm not sure about that).

What I gather is that the Earth-Moon interaction makes a cyclic variation, like nutation in a top, but that the average it cycles around stays much the same, and this relatively strong interaction tends to "shield" Earth from other effects.
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The Wikipedia article on the subject backs me up somewhat, though apparently "nutation" properly speaking accounts for much shorter term and smaller-scale variations than the main 41,000 year cycle that currently has Earth's axis oscillating by about half a degree each way. It cautions that in 1.5 billion years it is expected that as the moon moves outward from Earth it will enter a resonance with other objects (I presume mainly Jupiter) that will amplify the variation, and in 2 billion years a worse one will make them quite large. Possibly then if we backtrack to when the moon was closer there were other resonances that did the same in the past.

But of course a couple billion years is a very long time, about a tenth of the timescale we are looking at! It seems reasonable to assume the actual tilt was in the same ballpark as today, and if it wasn't so recently in our geological and evolutionary history that the darn article would remark on it! No guarantees of reasonableness with Wiki of course.:(

Anyway a 41,000 year cycle is an eyeblink on the timescale of Pangaea's existence; probably disagreements about the "beginning" and "end" dates of Pangaea, due both to lack of data and to varying definitions of our arbitrary names of a continuous process's "periods," are an order of magnitude or two greater than that!

So if the world we are shown in that map ever actually existed at all I guess we are entitled to choose an exact date on which the tilt exactly matched our own today, and probably have dozens of distinct ones to choose from.
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Here's an azimuthial equal-area projection, centered on the equator and 35 east longitude as defined by that map offered, that gives a sense of how much a "world-island" Pangaea of 260 million years ago was. Of course there are islands! I daresay the map is not even showing others that might have been. Looking up the history of the Hawaiian-Emperor chain suggests to me that either the hotspot currently forming the Big Island either might not have existed at all 260 mya or its path is obscured by having been inland in the "North China" island or beyond. But surely if that hot spot wasn't making island chains and none of the known ones today were either, some others were and had been for some time before, and there would be chains all over the vast Panthalassic Ocean not shown here. But of course these would only add a tiny fraction of land area.

But aside from such small masses, pretty much all the land in the world in this era clustered within 110 degrees or so of a point somewhat west and south of what I chose to show--I moved the center to the equator for convenience and to the east to focus on the main masses of land, not that small western chain which the labeled map omits completely and which I guess from previous looks at dynamic simulations is either Cuba or California or maybe the source of both. (Cuba, I know, did an end run from the Pacific around the southern tip of North America, what is now southern Mexico, into the proto-Caribbean, before the two American continents joined at Panama).

What would it be like to evolve or be ISOTed there? Assuming a set of ecosystems with animals and plants corresponding closely to our era rather than late Paleozoic/Early Mesozoic life, and a geological history such that there were oil and gas and coal fields already formed comparable to our own era's, I stand by my guess the big difference is, less jungles, more savannah and hard desert (though actually, looking at the two equal-area maps I offered, it looks like our world does indeed have a whole lot of desert). The temperate zones do look about the same. Considering that humanity evolved in East Africa, it looks to me like somewhere near there would be a corresponding ecosystem and so a species as close to ours as you like could evolve there, assuming their monkey-oid ancestors had someplace nearby to evolve in-that's the tricky bit.

From there I don't see much impediment to them fanning out both north and south along the east coast, along the shores of the Tethys ocean, and working their way into the temperate forests and grasslands of southern Pangaea--to get to comparable climates in Siberia, they might have to spend a lot of time as savannah and steppe dwellers on the shores of the strait between northern proto-Laurasia (is that the name of the region that splits off to later subdivide into Europe and North America?) before mastering enough boat technology to cross over.

But filtering into southern Pangaea should give them passage to the west central coast of modern South America (which had no Andes at this point) and up to the west end of the great Pangaea dividing range, around modern
Colombia. This strikes me as a possible Egypt-analog; many places along the savannah-desert boundaries might cradle some kind of riparine civilization. Or the temperate zones to the south might here be the origin of civilization. From there, south Pangaea has as much temperate area as Europe and China put together, the way I read the map. If anyone takes to seafaring, they can reach just about any point of major land on the globe coastwise.

So, if we were ISOTed to regions of comparable climate and ecology to wherever we are used to living--it's only the tropical wetlands peoples of the world I'd think would have to be stacked on top of each other, probably mainly in those central Tethys islands destined to become China. But Europeans and North Americans and Argentines and so on would have plenty of good land by our lights to wind up in.

260AzEqArea.jpg
 
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