What I am wondering is if the two sides of a planet are identical as far as climate and temperature goes. Beneath and above the equator, that is. Basically, I am thinking about starting to describe a setting where north means warm and south means cold. But is this true to how things work in the real world? I know it's fantasy, so I can do things however I want, I was just wondering.
So, in short, is there any difference between living a certain distance south of the equator and that same distance north of it? And could I make use of the plant and wildlife typically found north of the equator, at the other side of the equator?
The best way to describe it is that the northern hemisphere of your world is always the closest to the sun no matter the time of year keeping it in perpetual summer, perhaps the axial tilt is also greater on this world so that the north pole is a temperate zone rather than an ice enclosed landmass.
I'm not an expert but I believe what I have written is correct.
As for the question about creatures from the "north" of earth living in the "south" of planet X, there should be no problem, provided that the environment is conducive to these creatures. If your southern landmasses are mostly composed of tiny islands, there is little chance of huge herds of bison sweeping majestically across the landscape, but if there are large swaths of grassland, then bison should be fine.
My setting is flat. Water falls off the edge and is caught in a mammoth cup held by a Titan. The sun is a burning boat, and the moon a bowl, refilled from the cup... which another titan passed over the land to refill the clouds.
North is colder, south is warmer... and if you dig too deep you'll fall through and end up on the back of the Titan who is holding it all up...
Why make a planet at all? It's fantasy, after all...
My setting is flat. Water falls off the edge and is caught in a mammoth cup held by a Titan. The sun is a burning boat, and the moon a bowl, refilled from the cup... which another titan passed over the land to refill the clouds.
North is colder, south is warmer... and if you dig too deep you'll fall through and end up on the back of the Titan who is holding it all up...
That setting sounds ridiculously interesting.
It, obviously, revolves around the sun, but it's a 100% circular orbit, and the Earth 'wobbles' (tilts on its 'x' axis) as well, so that you get changes depending on what part of the globe your on. Thus the world is not 100% semietrical.
In addition, it's not just the sun that effects the weather. If , below the equator, you had a tectonically unstable area and multiple volcanoes, then, badda bing badda boom, the weather is going to be hot there, because the gas vents and lava eruptions are going to be throwing up so much heat.
Additonally, air and water currents will change climate dramatically. For example, I live in Japan. Now, Japan is along the same lines as Canada, but it almost never snows down here on Honshu (the main island) because of the prevailing winds, meaning that you can basically say whatever you want, and it's not terribly beyond the realm of reason.
Now, that being said, why do you want to make an entire planet. Just set your game on an island (or a contanant) and have the north cold, or hot, and the south reversed. No need to make an entire planet. Remember, this is DnD and the thought of traveling 200 miles in this setting is akin to going to the moon nowadays.
Hmm, I think you misunderstood me a little. Maybe I wasn't very clear. What I meant was, if a world with the same relationship to the sun as our planet has, would the climate be the exact same on both sides of the equator? Ignoring stuff like landmass, proximity to the sea etc.
It out of phase for starters...by about half a year. The problem is that landmass, coastal orientation, is always a factor.
If you want to apply the nasty little secrets of String Theory, the otherside of the world is different because the experiences of the People who live there are different. Maybe they choped down all the forest and its a continent sized desert. May be The Vorlon God Bujuu the Bucket-headed fell from the Heavens and now there is a molten sea of glass where he impacted.
However, with all of the complicated climate science that would be involved in thinking about a specific area and climate I would just say go with whatever works best for your game. Science is the realm of our world and should never be over done in an RPG because its always more energy than its worth.
Author's Note: However, science in our world is awesome only surpassed my mathematics.
It, obviously, revolves around the sun, but it's a 100% circular orbit
This is not perfectly accurate. There is a slight eccentricity to the Earth's orbit. The effect of eccentricity in the orbit is that it changes the length of seasons depending on how drastic the eccentricity is. Earth is not very (0.0167, w/ 0 = perfect circle) This is also slightly affected by how symmetric the orbit is about the larger body.
In addition, the orbit can precess, IE, the point in a year where the orbit is closest to the larger body can shift through the year. For example, on the Earth we follow one full precession every 10000 years, but it could happen faster or slower.
All this commentary assumes a single star of much larger mass than your planet. (On that topic, a binary star system might be an interesting, if complex world to model.)
As others have mentioned, assuming perfect symmetry, and at least some axial tilt, you have equal seasons, equal climates, and they occur out of phase by half a year.
You can also modify the axial tilt of the planet. This is the angle that the central axis of the planet maintains as it rotates around the larger body. This angle in space remains constant as the planet moves around the body. Increasing or decreasing the angle changes how strong the seasons are on the planet. Ex: A planet with an axis point at, or nearly at the larger body would experience extremely harsh summers and winters, while one with almost no tilt would have almost imperceptible seasons.
In addition to these considerations, you can also note wind patterns in the Earth. There are two bands of winds for the north and south, which rotate in opposite directions, and are separated by the tropics in the center. Like the seasons, their strengths are also affected by axial tilt, and the eccentricity of the orbit.
General rules of thumb for the Earth.
- More north / south equals colder (less average light)
- Higher altitude equals colder, while lowlands equal hot. (your area could be on a huge plateau)
- Weather moves from west -> east in the north, east ->west in the south
- Windward sides of mountains are wet, leewards sides of mountains are dry
- Large bodies of water produce a stabilizing effect near them (they store heat and then radiate it during cold periods and evaporate spreading colder moisture during hot periods)
Beyond these, you would need to start really reading up on Climate and Plate Tectonics to get an accurate grasp of how landmasses form, and their effects on weather and climate patterns.
Anyhow, hope that answers the question.