Case Study: Menducia
Ignoring the tricky question of animism (whereby physical "things" have an animating "will" that can manipulate the physical, even against the normal laws of elemental motion), the basics of Menducian physics runs on the elements. Menducian elements are less materials than "the property of a point in space at a point in time". The Menducian cosmos is best visualised as a very complicated - at any given point in time each point in space is assigned a value (element), nothing truly moves, but each configuration gives rise to the next predictably via . The imageis a handy guide to the names of the elements and how they relate to each other.
However, the specifics of this are the Menducian equivalent of molecular physics - we want a slightly broader look. On a larger scale Menducia operates a lot like the real world, at least in that there are "objects" that "move" (like a glider in a cellular automaton) according to certain "forces" (generally derived from the elemental structure of the object, but also related to the elements surrounding an object).
The basic structure of the cosmos Menducia finds itself in is this: Menducia itself is a large central concentration of Earthy elements in a sphere about the size of Earth, with a layer of Watery elements (the oceans, and to a lesser extent the atmosphere) around it. That is suspended in a vast area of Airy elements (outer space). Other, minor bodies are suspended in the Airy layer, including Menducia's many small moons and the sun, a large concentration of Fiery elements that also orbits Menducia. The sun also has two tiny "solar companions" orbiting it, also composed of Fiery elements. Beyond that the specifics are unknown, and fortunately, not relevant.
What heat source(s) does your world have? What causes heat/temperature variation, and why?
In Menducian physics, Heat is a point on the elemental map. The closer an element is to this point (between Fire and Air), the naturally hotter it is. Air and Fire are therefore naturally hotter than Earth and Water, with Mud (sitting opposite Heat) the coolest element. However this only applies to pure elements, which are rare on large scales. Most objects and materials on a human scale are mixtures, which can have more or less Heat and hot elements added or subtracted (resulting in a corresponding change in the object's properties).
The only major source of Hot/Fiery elements on Menducia is its sun (the solar companions are too small to have significant effect). On the whole Heat tends to radiate away from the planet into space, but it travels at such a rate from the sun that it overcomes the general repulsion (partly to do with it being very pure, at least at the outset - as it travels towards Menducia it reacts with the Air and becomes less so, and so slows down. As it reaches the atmosphere (Air/Water boundary) it's often reacted and diffused enough through other elements that the force pushing it away from Menducia has been weakened considerably, but there has still been a considerable shift in the local elemental structure towards Heat.)
Temperature variation comes from two very familiar cycles - the day (the rotation of Menducia on its axis, so that any one point on the surface may be facing towards or away from the sun), and the year. The year is the time it takes for the sun to make a complete orbit of Menducia. It does so on a plane at an angle to the plane of Menducia's equator - this, rather than an incline in Menducia's axis of rotation, causes seasonal variations in the amount of sunlight .
(All this is mathematically relative - what causes seasons, on Menducia or Earth, is the angle between the plane of the ecliptic and the plane of the equator. If we took the Earth as a stationary point, with the axis of rotation at 0 degrees, and measured the movement of the Sun relative to it, we'd end up with a similar picture. Equally you could make the Menducia system heliocentric, in which case its axis of rotation would be inclined relative to the plane of its orbit - just like Earth's).
There is a third cause of large scale temperature variation. The angle of the sun's plane is not fixed, and changes slowly over billions of years. If I wanted to record Menducia's climate over millions of years I would have to take this into account. Fortunately I only want a picture of recorded history, about 10,000 years, and there won't be significant variation over that period.
Do different parts of your world heat and cool at different rates? If so, how and why?
Due to their differing elemental properties, land and sea react to heat differently. While the oceanss are "naturally" warmer than the land, they have less capacity for Heat - the addition of Heat to Water quickly produces light elements that radiate away from the main body of water, keeping its temperature relatively stable. Earthy elements on the other hand can soak up a lot more Heat before elements light enough to float away are formed, but also repel and lose Heat faster than Water. So, the land heats and cools faster than the oceans.
What principles govern atmospheric movement? Does heat drive air movement, or some other force?
Menducia's atmosphere is a mainly Watery/Airy mix of elements. If it was pure Water/Air, its movement would be highly unpredictable. Fortunately, "light"/"hot" (strictly, Fiery) and "heavy"/"cold" (Earthy) elements also play a part. Hotter parts of the atmosphere rise (are repelled by the Earthy core of Menducia), while colder parts sink (are attracted down).
The further hot air rises, the more Fiery elements it loses as they escape into the upper atmosphere and eventually, space. So hot air cools as it rises, then sinks back down where it picks up excess Fiery elements from the land or oceans, and rises again.
Sinking air eventually hits the land or ocean and spreads outwards from there, picking up heat (and over the oceans, moisture) as it goes. This causes a general flow of air from colder areas to hotter ones, at least in the lower atmosphere.
As Menducia is a rotating frame of reference, all this movement will be subject to a Coriolis effect.
What causes rain and other precipitation? Is water vapour carried by the air, or is some entirely different principle at work?
Watery elements are carried in the atmosphere, and fall as rain when they become heavy (less Fiery/more Earthy) enough. This happen particularly when hot air rises and begins to lose its Fiery elements (see above). Cold, sinking air has generally already lost much of its Watery content, and will rarely produce precipitation. Hot air can also carry more Water than cold air, following a similar principle to that which governs how much Heat can be held by Earth vs Water - Hotter mixtures are lighter, and so can bear more heavy elements to be added to them.
In summary, the basic principles driving Menducian climate are:
*All heating comes from the sun
*Water heats and cools more slowly than land
*Hot air rises, cold air sinks
*Winds flow from cold-air areas to hot-air ones
*Corilolis effect deflects winds to the clockwise in the Northern hemisphere and anticlockwise in the Southern hemisphere
*Rising air is conducive to the fall of precipitation, sinking air is not
*Warm air carries more moisture than cold air
This should all look eerily familiar.
"It is quite certain, in particular, that I have always been insane." ~ Aleister Crowley
"Save us all from arrogant men/And all the causes they're for/I won't be righteous again/I'm not that sure any more." ~ Shades of Grey, Billy Joel