Coasts now account for the poles and the East/West wrapping.
Here is a pic with the Precipitation zones outlined.
Blue = Wet (Jungle & Coniferous Rain Forest)
Green = Moderate (Deciduous Forest & Boreal Forest)
Yellow = Semi-Arid (Steppe, and Grassland)
Orange = Arid (Desert, Steppe, Tundra)
So depending on the latitude, different precipitation levels result in different vegetation.
Now I will see if I can wrap the world visually in the game. Anyone have any ideas on how that is done?