The Winter of a Hundred Years

[JohnWDaileyGLE]

Back home, one ice age during the two and a half million years of the Pleistocene lasted a total of 100,000 years, ninety thousand of intense cold followed by ten thousand of milder interglacial weather.

But in this alternate Earth, we've been in an ice age for five million years, with glaciations lasting 150,000 years followed by interglacials lasting 12,000. Would a longer Milankovich cycle result in a different climate, a different landscape and a different extent of the ice?

[LoA]

As far as landscape is concerned, absolutely. More ice, more erosion.

Climate wise, yes, but I don't know to the extent of it. All the water is wrapped up in the glaciers, so that means lower sea levels, and I know that would effect climate, I just don't know how.

I'm not sure if the ice extent would be any different though.

[JohnWDaileyGLE]

"As far as landscape is concerned, absolutely. More ice, more erosion."



Care to be more specific?

[LoA]

"As far as landscape is concerned, absolutely. More ice, more erosion."



Care to be more specific?

Basically the more glaciers there are for longer periods of time, the more it's cutting through the landscape through it's natural movements, and through all of the water that's melting and creating rivers. To be honest though, it probably wouldn't be drastically different from our earth, but I imagine it would be different enough to bring to attention.

[Steerpike]

But in this alternate Earth, we've been in an ice age for five million years, with glaciations lasting 150,000 years followed by interglacials lasting 12,000. Would a longer Milankovich cycle result in a different climate, a different landscape and a different extent of the ice?

This sort of questions seems very difficult to answer for anyone some fairly extensive knowledge of climate science. Do you have a setting in mind here that you're trying to arrive at? Like, are you trying to imagine a setting in which various human/oid societies develop in an ice age? Or is this part of a transdimensional sort of setting where explorers visit alternate earths?

[JohnWDaileyGLE]

This sort of questions seems very difficult to answer for anyone some fairly extensive knowledge of climate science. Do you have a setting in mind here that you're trying to arrive at? Like, are you trying to imagine a setting in which various human/oid societies develop in an ice age? Or is this part of a transdimensional sort of setting where explorers visit alternate earths?

The latter, yes.

[Steerpike]

Okay, cool. So are you envisioning stories or scenarios about colonizing these worlds? Warfare between alternate dimensions? Espionage as in Banks' Transition? Communication, at the very least?

Describing alternate andscapes and imagining counterfactual earths is interesting academically as an exercise, but I'm looking for the sources of conflict, human or otherwise, that might bring the setting to life. I assume this is the same multiverse as Great Lakes Earth, about which I had similar sorts of questions. Getting the specific hair colours of alternate Europeans is cool and everything, and there's obviously a ton of thought poured into how different geological ages played out, but there wasn't a lot about how those people lived or organized themselves, or what effect knowledge of the different dimensions has, or what the overarching goal of creating these alternate worlds is.

I guess I'm simultaneously intrigued by the abundance of physical detail you're looking to generate while also a little confused as to the overall point of the setting. Is this all background for something? And if so, what is that something?

[JohnWDaileyGLE]

The entire alternate history textbook is still in progress.

[Steerpike]

Interesting. So is the textbook an end in and of itself? Are you imagining it as background for a roleplaying game? A novel?

EDIT: I'm just trying to get an overall sense of your project as a whole, here, and what you're actually trying to create. What we've seen so far is rigorous in its details to a level very rarely seen in worldbuilding, but makes me feel a bit puzzled as to what it's for. Is the project one of describing other earths purely for the sake of description?

[JohnWDaileyGLE]

It IS a bit overwhelming, I can admit that.  But this is pretty much a blueprint for future alt-history fictions.  You must create a world and history hope that they pass off as realistic and believable before going crazy with your embellishings.

[Steerpike]

It's not that it's overwhelming per se, it's more that the approach to worldbuilding is very unusual, so it's tough to see where you're heading. A lot of your question seem a bit like you're quizzing us, or expecting very technical or scientific answers. There's definitely some scientific expertise amongst members of the site, but I doubt you're going to get exhausitvely detailed answers (Llum's answer to your underwater city question would be the closest).

You must create a world and history hope that they pass off as realistic and believable before going crazy with your embellishings.

I think this is totally fine as an approach, but I definitely don't think it's the only "correct" one - or even the usual one. Generally I think most alt-history fiction begins with an idea for the kind of story it wants to tell and then back-projects the necessary detail to give itself a sense of verisimilitude. I don't necessarily mean a specific plot, or anything, I just mean the overall scenario. To suspend disbelief and immerse in a world most people don't need to know about that world's tectonic activities or orbital patterns, unless they were deeply relevant to the story in question. I'm not objecting to this approach, mind you, though I am somewhat skeptical about the reliability of any answers to the questions you're posing without incredibly exhaustive research and modelling.

[LD]

You must create a world and history hope that they pass off as realistic and believable before going crazy with your embellishings.

Most people are willing to suspend disbelief if the story is interesting. See Star Wars, for one example :D. Regardless of if you think it is interesting, it's successful. :).

Stories are what matters. The framework often serves the story rather than the other way around.

That said, as Steerpike stated, if a rigorous background is important for you, that is fine as well- many Hard Sci-Fi fans and fans of the "what if" historical fiction/ alt-fic genre would likely agree with your approach to start with the what if and then to brainstorm a story that fits the what if, which can be very difficult to execute well. What is important is to do what makes sense to you and what you enjoy. :).