How To Make Wind and Influence Climate

[Porklet]

Sorry I don't have time to comment on the entirety of your post atm. Loos like JB has some awesome info for you. However, the statement above kind of flashed red when I read it. First off, I'm assuming you meant 12,000 miles in circumference around the equator, not diameter, since you said you were halving things. A planet with 1/2 the circumference of the Earth is going to have about *1/8* the volume of the Earth (and assuming it is proportional, about 1/8 the mass), which would give it physical characteristics much closer to Mars than Earth. If this is a naturally evolved planet, a lot of your breathable gasses aren't going to be gravitationally bound to your planet, and you're going to wind up with something tenuous at best. Of course, you could say that your smaller planet has a mass similar to Earth's, but then, all that extra metallic iron in your planet's mantle is going to wreak havoc with your magnetosphere, turning everyone's brain synapses into a fine paste. Your planet would also rotate somewhat more slowly since it doesn't need to go as far to get that 24 hour day, resulting in much decreased wind patterns, weather, and climate. Also, I'm not sure a lot of Earth climatology models would be comparable with a planet with that much decreased surface area.

When I was designing my world, I hit a lot of walls as well when trying to keep it habitable and similar to Earth and yet, at the same time, throw some variety in there. I managed to acquire a lot of leeway in making it a world terraformed by a highly advanced culture (with remnants of their terraforming technology still in place and functioning), but every time you tweak something it has the potential of throwing a lot of other things out of balance. For example, by making a planet where life had never evolved naturally on its own, I inadvertently deprived my developing civilizations of the primary fuel source (fossil fuels) that got humans through the industrial revolution. Whoops.

Check out this list of things needed to have a stable, habitable planet.

I did mean circumference, but since it won't work as I envisioned I am not opposed to doubling the size. When I started this thing, o so many years ago, it was 1,000 miles by 1,500 miles, and it only included the mainland and few small islands. I've come this far, what's another 3,000 miles? The distance from the equator to either pole is roughly 6,000 miles, correct?

I am working with a 3,000 x 3,000 pixel map that stretched from 75 degrees N to 15 degrees S (or 90 degrees). It was one mile per pixel, but at 2 miles per pixel the distance from the top of the map to the bottom following the same longitude should be 6,000 miles. Is that right?

Since I stared recreating this world it has grown and changed a lot. I'm OK with a bit more.

I am still reading thru the info JB provided, and I'm deciding how far I want to take this. The Summer/Winter wind patterns, upper ocean currents, hurricane activity, rainfall, regional climate, and curious or unusual weather patterns are pretty much the limit. I am looking into the H/L Pressure systems, jet stream, and deep ocean currents. I am redefining the Rain Shadows based on JB's new information. I will post tonight.

EDIT: It might be childish, but I can't help but chuckle when I read the word panspermia in the article you referenced above. It happened again.