My Fantasy RPG World, Feedback and Ideas appreciated

The Coriolis effect isn't caused by the Earth's shape, but by its rotation.
So as long as your cylinder rotates, there will be a coriolis effect.

I assume your cylinder rotates along the axis that goes through the flat surfaces?
Then you will even have two types of coriolis forces: one on the flat surface, one on the curved surface.

Very simply speaking: as you move, the Earth (same goes for the spinning cylinder) tries to rotate away below you, which makes your path curve toward the opposite side of the rotation.

The effect does not happen if you move parallel to the direction the body rotates (east or west), in that case you move in a straight line. It is strongest when moving south or north.

It is a tiny bit more simple on the cylinder than on the sphere, but it happens in the same way.

On the top and bottom of the cylinder there is also a Coriolis force, it bends your path in the same way it would on a flat, round, spinning plate.

 

Uuhmmmm.... what?
So the cylinder is hollow?

About prevailing winds.... I'll make a post about it once I am at my PC. I will have to go a tad more into detail there.

 

Ok, I'll try to explain how I think weather could work there, in halfway simple terms.

I'll start with how it works in real life, on Earth.
First of all: Weather is complex. Very complex. I have had a whole semester of meterology at the university, I have learned meteorology for both the pilot's license and because of psersonal interest, and I still only grasp the very basics.

The main factors for how weather cells evolve are gravity, pressure, temperature, the shape of the Earth (like mountains) and the coriolis effect.

There are high pressure zones near the poles. That's because the air is cold, so it tries to fall down toward the earth. Gravity is also stronger at the poles (because there is no centrifugal force to offset it, and also because the Earth is not spherical but a oblate spheroid). The ground is in the way though, so the air moves sideways, away from the poles.

Near the equator it is warm, the centrifugal force is stronger, and gravity is lower. That makes the pressure lower.
That creates what is called the "equatorial trough".

Pressure always tries to equalize, so the air flows from the poles toward the equator, in a straight line from north to south (and the other way round on the southern hemisphere)

The coriolis effect turns that straight motion into a curved one. The Earth rotates to the east, so the winds have curved paths toward the west.

But wait, that's only near the ground. Of course at the top of the atmosphere it works the other way round. That creates something we call "Hadley Cells".

At some point those downward winds meet those flowing toward the equator in their bent shapes.
As you can imagine, winds moving in opposite directions but meeting each other causes turbulence.
That's what causes this:








Once those meet mountains or bodies of water that are large enough, things get really complicated.

Generally speaking: Water and land are heated up by the sun, but not at the same speed. They also cool down at different speeds, which causes the typical winds toward the land or away from it.
Those lessen or strengthen the prevailing winds we have learned about above.

All those local minimums and maximums in pressure shape the cells we know, as air wants to flow away from the centres of high pressure twoards the zones of low pressure. Coriolis forces make those shape the cylcones we know.

Mountains tend to be in the way of winds, forcing them to either go around, or over them. That causes effects, because humidity, temperature, and pressure are all related to each other. If you force humid, warm air up a mountain, then it becomes colder and cannot store all the humidity. It loses the water (rain). That in turn changes the air's properties.
Also: when you blow air over a mountain, there will be lee waves behind the mountains. That also changes the weather.
That's why the Atacama desert or the Gobi desert are where they are. The Andes cause the Atacama, the Himalayas cause the Gobi.




Now, that's VERY basically how weather works.
I'll try and think about how that would apply to a cylinder. Most of it will probably still apply.

 

So much good stuff on geography and physics in such a short time!

Mahrlect, I hadn't thought of that. I guess I just kind of assumed that rain fronts would come from the sea. Rain from the east woudl get stopped by the mountains. Rain from the west would gradually exhaust itself over the land. But I suppose by that logic, the much larger continent West Colassia, especially Fumaya would be bone dry.

I guess I can go back to Greek mythology. Egypt is a desert because Helio's reckless son drew the sun chariot too close to Egypt and scorched it. So I'm going to lean into that. Rain shadows from mountains and land masses has some impact but when elementals ran amok, the areas where fire elementals attacked in force because arid environments forever. Because of the ambient fire elemental energy, rain falls from the sky less often. Because crossing bodies of water is difficult and painful for fire elementals, deserts near the sea are pretty rare.

I guess since the East Colassian mountains represent the marching line of a bunch of earth elementals I should through in a couple small volcanoes where the desert and mountains meet because that is what happens when earth elementals and fire elementals mix according to my own established lore. Maybe the most active and predictable volcano can be claimed in Magicland. Volcano based forges are fantastic for crafting magic items.

This could also give nations near the mountains more access to igneous and metamorphic rock.

I guess no Coriolis Effect. Also, I don't think Nami the Chaotic Neutral goddess of weather would want weather to be that predictable, though she would still be limited by elemental forces because it would take more work for her to cause precipitation in areas with a lot of ambience tied to the elemental force of fire.


I do love the science lessons on the Coriolis Effect.

I'm undecided to if the world spins or if the world is stationary while the sun, moon and stars rotate around the cylinder. So assuming is not a good idea.

So option one is that the cylinder of Scarterra doesn't move. Khemra and Zarthus steer the sun and moon around the world and the constelations lazily drift around the sky like detrius on the sea.

Option two is that the sky is more or less a static entity and Scarterra moves and spins, possibly fueled by the elementals in the center of the earth like hamsters on a wheel.

Well said Pendrake! You remembered something from my far more than 22 word cosmic backstory!

Hmmm, I guess since the Void acts as a heat sink that would make the predominant wind cycles be north to south as the poles pull heat towards themselves. The equator would not only be the warmest, but it would be the least windy. That actually works twice because I already established that people born and raised near the poles tend to have Air infuence in their inherit traits.

Since the very basic description is actually fairly complicated that explains why people think the weather is random because random often means "Affected by things beyond our understanding). I was born and raised in the American midwest where we can move from using the heater to running the air conditioner and make over and again. That's kind of why I made the weather deity Chaotic Neutral.

I will admit that me living far away from mountains and the ocean makes weather less predictable. When I spent time near mountains or the sea you could almost set your watch by when it starts raining.

Neve the less Nami is mildly interesting in providing weather that is beneficial to mortals but for the most part she alters the weather when she gets bored. That's not to say the other deities have no power over the weather. The deities can influence the weather in small ways with effort. Any cleric can learn weather magic, not just Nami though they do this seldom because Nami's priests and priestesses have a difficulty break when using the weather control power.

A lot of weather and geological forces are the results of elemental forces. Especially when elementals ran amok during the first Unmaking.

The ebb and flow from the tide marks areas where earth and water elementals fought.

Most mountain ranges are the remnants where large numbers of earth elementals marched in straight lines.

Deserts are the result where fire elementals stamped an area with their essence which makes rain fall difficult there.

I guess air elementals would inadvertantly creating prevailing wind currents but to be honest, I generally envision fewer air elementals joining the massive riots than the other three elemental types.

I guess the gist of it is Nami does what she wants but elemental forces can make certain weather easier to force. If Nami wants to make it rain in the desert or snow in the summer she has to work harder to make the weather stick.

Rivers often follow the paths of water elementals who crossed on land though rivers are less influenced by elementals. They existed before the unmaking. Mera helped direct rivers to provide water for thirsty creatures. Mera is the god of the sea but I haven't figure out how much influence she has over the sea. I do know she tries to make ocean currents easy to travel on because she is so nice and that Greymoria loves to sabotage her and make the sea and water in general more dangerous. Greymoria's followers frequently drown their victims.

Finally the Void acts likes a heat sink on the poles because the Void has Turoch's essence and it wants to consume all life. The Barrier that holds the Void at bay weakens every year on the anniversary of Turoch's death and then is strengthened as the Nine repair it. This creates Summer and Winter.

So I guess the main impacts on prevailing weather patterns are

1) The meddling of millions of elementals during the First Unmaking.
1a) Fluctuations when lesser disruptions of magic energy create small numbers of rogue elementals.
2) Proximity to the poles/Void and the fluctuations in the Barrier to the Void
3) When Nami gets bored and tries disrupting things for fun
3a) When the rest of the Nine countermand Nami's control of the weather to help their favored mortals.

4) Something with the ocean currents?

I probably will get an idea for ocean when I get around to making a parallel cosmology for merfolk and all the other sea creatures.

I don't see gravity having an effect. Scarterras kind of runs on a mythological basis. Mythology explains things that change. Lots of mythologies explain how the sun rises and sets, why the seasons change, why different areas have different climate, why the leaves fall off of trees. Gravity is constant so there are few myths about it. I'm not aware of any ancient myths about why things fall down, that's just taken for granted. Like rocks. A lot of myths involve rocks but very few myths question why rocks are there. One of my favorites is when a rock teaches a shaman the secret of building sturdy homes out of stone in exhange for the shaman teaching the rock how to fly (by making stone arrow heads).

Enough tangent on rocks. Sadly the story above relies on an animistic world and I don't see animism being a good fit for my RPG world. If I created a setting with lots of relatively weak gods instead of nine very powerful gods I probably would use animism (the idea that everyone and everything has an assocaited spirit) as a base aspect of reality. I guess it's a lot easier to make myths when the sun, mountains, and river are all sentient beings.

 

Hmmm OK.
As interesting as this is from a fantasy point of view, I fear that I won't be of much use here.
I tend to adhere to the rules of physics for many things, just because I cannot imagine how a world without physics would look like.
Too much scientific background can hurt, I guess.

 

If - for some reason, it is up to the gods I guess - there is a significant difference in temperatures, then we could get some movement of the weather going on it's own.

Example:
Let's assume the cylinder doesn't spin, but the sun moves around it.
Let's also assume that the sun is similar to a real star, so quite a bit away and quite big.
But this hypothesis would work similar in most ways if it is basically the way some people in history thought the world worked, so a small, close sun.


So that means that there is always a hot area of the cylinder, and a cold one on the other side, with a heat gradient between them.
If the cylinder's diameter isn't radically different to Earth's, and the same goes for the atmosphere, rocks, and liquids, and the day's length, then that should be a difference of around 15-20°C between the maximum and minimum temperature in a day.
I based that on the numbers from cities close to the equator, like Quito, Libreville, and Nairobi.
Generally speaking it would be more difference on land (like the 20°C from Quito) and 15° when close to the sea (like the 15°C from Libreville).

There would not be a big heat gradient between the areas near the barriers, unless the sun is very close, small, and the atmosphere is relatively thick.
That would basically mean that there are no climate zones, unless there is significant geothermic activity in one part of the cylinder or another.

If the sun's orbit isn't inclined, then there are no seasons. If it is then there are seasons.
Again, if the cylinder itself is heated from the inside, like by a heater that slowly moves up and down inside the cylinder, then there might be seasons as well.


So until the heat question is answered: let's assume that there is no such heating, the only heat source is the sun on a non-inclined orbit around the cylinder.

That would mean that there is a temperature and pressure gradient leading from the day side to the night side. That would cause good weather at noon (warm, high pressure), a west wind in the afternoon, and an east wind in the morning. In the night there would be rain probably.
There could be something like a Hadley cell forming between the day and night longitudes, so in high altitudes the pressure would work vice versa. That could cause some down- and upwind drafts. So that's where the local pressure zones would form over the oceans.

The problem is: that's pretty short lived. The pressure changes over the day would change too quickly for weather like we know it to form.
The lack of coriolis force would prevent low pressure areas from spinning, so they would be a lot less stable, unlike the ones we know from Earth that take weeks to equalize the pressure difference, so they move around and cause interesting weather.


If the cylinder spins, then (as strange as that sounds) most of the atmosphere would move with the ground, because of friction. In the same way that if you spin up a glass of water, the water will eventually follow the rotation of the glass.

For winds like those on the Earth you will need a spinning cylinder and a pressure gradient (most likely because of temperature difference) between the barriers and the middle of the cylinder.
Then the coriolis effect would create a system resembling the one on Earth surprisingly closely.

 

The diagram is super awesome by the way!

I don't see the point because nearly all Void Demons can fly. They also aren't very materialistic or have much to work with visa vi physical matter.

I hadn't thought of this but it sounds cool. My original plan was that Void Demons would be psionicists and they could expediate travel by sling shotting across the Astral Plane but my players were pretty clear that they are uniterested in playing in a world with psionists. At least while both my setting and dice system are in the beta test

Yes, both the "north" and "south" Void are technically the same space. It's kind of like Pac-Man if you ever played it. If you walk off the right edge of the screen you pop up again on the left edge of the screen. If you walk off the right edge of the screen you pop up again on the right edge.

But space and direction in the Void are not fully linear and they are partially absed on the subjective views of beings in the Void. If a demon (or uncommonly powerful mortal) in the Void has sufficient willpower and mental discipline, they can

I don't see the point because nearly all Void Demons can fly. They also aren't very materialistic or have much to work with in terms of physical matter.

I hadn't thought of this but it sounds cool. My original plan was that Void Demons would be psionicists and they could expediate travel by sling shotting across the Astral Plane but my players were pretty clear that they are uniterested in playing in a world with psionists. At least while both my setting and dice system are in the beta test.

What is the difference between leaping and sailing?

The Demons are split into different castes differentiated primarily based on their raw power and their specialized roles. More powerful demons are usually physically larger than weaker demons. I have thought about creating a caste of "Infilitrator Demons" that are shapechangers and size changers but I havent comitted to it yet. They are certainly not going to be a lot of them. They would be crazy powerful and cunning.

I have honestly not though of this. This is a plot hole that needs shoring up. Something needs to stop them from going over the barrier because Demons can fly and it would challenge logical metaphysics if the Barrier was truly infinitely tall because nothing the Nine does is literally infinite, just very big.

I suppose my working theory is that the Void is fully contained and enclosed. I suppose I can lean into the idea that linear space is subjective and warped so that if you go "up" far enough you are forced to come back down.

 

Because Google is logging my keystrokes, this video came into my feed. I'm curious if this spurs new ideas or drawings from you.



This is what I used as a baseline.

I lieu of four elemental planes I have one elemental plane in the center of the planet's cylinder. Rather than explaining the inhabitants and beautiful cities like D&D does for the Elemental Planes I put the lazy explanation of "No one knows what the Elemental plane looks like or how big it is because mortals cannot survive there."

I didn't intend this way because I decided the plane of Shadow (now called Shadowfell) served no narrative purpose and I wasn't even aware that D&D 5th edition has a Feywild realm. But apparently my Fae Realm is kind of a hybrid of the Feywilds and the Shadowfell. My Fae Realm was severely damaged from a Void Demon attack so the Fae Realm has regions of desolation and death and regions of wonder and beauty.

D&D has both the Astral Plane and Ethereal plane as sort of a network plane that connects all the other planes. In 3.5 the Astral Plane, Ethereal plane AND the Shadow plane served this purpose. I opted to only have one ueber-plane. In Scarterras the Astral Plane links the various planes together. My version of Astral Plane doesn't have dead gods in (that's the Void). Mine is based more on sc9-fi than fantasy. The Astral Plane is a realm of pure thought.

I'm still working on the Scarterran equivalent the Outer Plane. I like the idea that there are planes in the sky that correlate with the constelations. Each of the Nine created their own personal version of a utopia for their favorite worshippers to dwell in the afterlife. Since a lot of Scarterrans are polythesists I need some sort of place for them to go. I'm thinking of creating a sort of star and cloud version of the D&D Outlands.

I've also pondered outer planes that are not directly tied to the Nine. I like the idea of a realm of primordial life where every animal that has every lived can be found. If I ran my setting in D&D 3.5 or 5th edition I certainly would include this real so druids have some where to conjure their minions from but I'm not 100% such a realm is necessary in my homebrew system.

Other thoughts I had include a divine archives or library. A prison for mortal souls who managed to offend the Nine collectively. A divine "kitchen" where the primordial souls rescued from Turoch are kept since if a new race is to be created the Nine usually create their first batch of mortals out of these primordial souls. I could create a bunch of outer planes. The sky is quite big.