Things start to get a bit more interesting now (and colorful).
The next task is to add the effect of the major mountain chains on rainfall. As the wind blows and encounters a mountain range it rises cools and any moisture falls as rain. on the other side of the mountains a rain shadow forms because all of the moisture from the air has already fallen.
So using the prevailing wind directions shown previously the rainfall map can be modified to show areas that would be drier than expected and wetter than expected (the black lines represent the mountain chains):
Next stage is ocean currents. A bit of a dark art this one so I'm going to stick with the basic rules and fly by the seat of my pants. Been a while since i did any oceanography so if anyone in the know sees any glaring errors please let me know.
The first rule is warm water flows from the equator to the poles and vice versa. The ocean currents are affected by Coriolis Force and so bend to the right in the northern hemisphere and to the left in the south. Obviously the shape of the land will affect flow so using these basic rules my worlds ocean currents look as below:
Ocean currents are very important at distributing heat so i can modify the earlier heat map as the ocean currents shown above carry warm water to the poles and as cold water returns. This gives an ocean temperature map as below:
Although its unlikely a fantasy map will never show ocean temperature this is very important on later land types. For example the warm ocean current flowing past the northern island arc means they will be much warmer than the latitude itself would suggest. The ocean also acts as a thermal blanket keeping costal areas milder while inland regions cool much faster. So using this and the ocean temperatures i have spread the effects onto the land to give the land average land temperature map:
Just for the sakes of a pretty map i combined the two temperature maps:
So now we have all the essential data i need to do the map. The next stage is producing a climate map showing how the tundra, desert, rain forest etc will be positioned.
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