Now that the physical landscape of our region has been mapped out, we turn to the next stage, giving the region its weather, and through that, its terrain.
To begin with, we need to know the climate of the region. On a normal world, you have tropical regions at the equator moving through to arctic at the poles. Of course, various factors may make that differ. On ours, we have less of an axial tilt resulting in a smaller arctic zone. For worlds starting out at this design step you can roll for what climate bands are present. Given we are taking ours from the world map, we can work it out for this region from the world map. The polyhedral maps that come with the book have the climate bands marked on, and from that we can judge where they would be on our map. They end up looking like this;
It is quite a range of climates we have, from the cold subarctic in the north to the warm subtropical in the south, though it is mostly temperate.
Altitude also plays an effect on climate. Higher elevations are cooler than lower ones around it. A mountain range and its foothills, the highlands, drop one climate band, so that in a temperate zone they would be subarctic. The peaks themselves would be two climate bands lower, so in this case they would be classified as arctic.
The following map shows those regions on the map, with the highlands (one band cooler) in orange and the peaks (two bands colder) in grey.
Combining the climate bands, the altitude and the prevailing winds (which we have already mapped out) we can now work out the types of terrain that are present. For each block of terrain, usually between natural boundaries like mountains and seas, we roll to see what the predominate terrain is, based on the climate band and whether the prevailing winds are humid or arid. Arid winds are one that form over large land masses, which we don’t have, so the prevailing winds here will be humid.
The predominate terrain for each area isn’t the only type that will be present, it is just the most prevalent. For example, arid sub-tropical regions could have barrens, deserts, scrub/brush or grasslands. One will be predominant, such as scrub/brush, but the other types will be present in patches throughout it.
Starting on the large island, we roll for the mountain peaks, which are either humid/subarctic or humid/arctic, depending how you read the rules in the guidebook. As these are medium mountains in a temperate zone, at one point it says that they are treated as humid/subarctic while in a temperate zone, despite it only being one climate band down. We will go with that, which gives us options for marsh/swamp, light forest, medium forest, moors or glaciers. Of the options given, swamp/marsh is not allowed in medium mountains, but the rest are (though there might be some small patches of swamps in valleys.) On a 1D8, we roll a 5, which gives us Light Forest. The mountains are dominated by needleleaf evergreens, like in taiga forests. There might also be medium forest, moors and glaciers around as well.
The foothills to the east of it are humid/subarctic as well. On a 1D8, we roll a 6, which gives us medium forest, denser broadleaf evergreens. The interior of the island is turning out to be one larger forest, one that thins out the higher you climb.
We continue on doing the same for the rest of the map, resulting in plenty of forests, but also regions of marshes and moors and even some tundra, glaciers and steppes. The final map looks like this;
Next time we move onto the rivers and lakes of the region – and the inhabitants.