Having a map of your world is great. But now you need to know what the climate and weather are like. Is it a hot world, a cold world, or is it just like the Earth? You have a lot of choices. This can be fun to do, but it can also be a lot of work, depending on how detailed you want to be.
Making a Climate Map
So, you have your map ready, all of the shorelines, rivers, lakes, and mountains drawn. What do you do next? Well, you need to know what kind of climate each area has. You can do it simply, if you like. If we look at a simple method, let’s assume that the world is similar to Earth. At the equator, you’ll have tropical rainforest. Moving north and south, you’ll then have savanna, then desert or semi-arid environments. North and south of that, you’ll get into a more Mediterranean type climate, which is dry, mostly grassland, but temperate. Then you get the temperate forests. Moving even farther from the equator, you find boreal forests, tundra, and finally ice caps. This is a very simplistic look at it. It’s much more complex.
Let’s take a look at the Koppen climate classification system, which can be very useful when determining your world’s climate zones. I’ll look at the zones briefly, but you can check out the Wikipedia page for more detailed information. There are five climate groups. Each group has more specialised climates.
First are the tropical/megathermal climates. These are wet climates. The main types here are tropical rainforest (rainy all year, no seasonal variation), tropical monsoon (seasonal wind changes resulting in rainy and dry months), savanna (this has a very dry season).
Next we have the dry climates. There are two main types here, the desert climate (the driest) and the steppe climate (not as dry, but still semi-arid).
Third, we have temperate/mesothermal climates. These climates generally have warm to hot summers and cool to mild winters. The main types are dry-summer subtropical or mediterranean climate (hot and dry summers and rainy winters, western coast), humid subtropical climate (hot and humid, rainy summers and dry winters, eastern coast), maritime temperate or oceanic climate (changeable weather with lots of clouds and wet weather, cool summers and mild winters, western coast), temperate highland tropical climate (dry winters and rainy summers, located at higher altitudes), maritime subarctic or subpolar oceanic climate (confined to coastal strips or islands, generally colder than maritime temperate/oceanic), dry-summer maritime subalpine climate (very rare zone, highland areas near the coast where the ocean prevents the winter from dropping below -3 degrees Celsius).
Fourth, we have continental/microthermal climates. Basically, summers are warmer, winters are very cold. For this, we have hot summer continental climate (hot summers, sometimes dry, sometimes wet), warm summer continental or hemiboreal climate (very simply, summers are warm, winters are cold), continental subarctic or boreal climate (pretty far north, mild summers, very cold winters), and continental subarctic with extremely cold winters (-38 degrees or colder in winter, only in Siberia).
Finally, we have polar and alpine climates. These occur at the poles or high up in mountains. The two types are tundra climates (warmest month is between 0 and 10 degrees Celsius) and ice cap climates (all twelve months are below 0 degrees Celsius).
Of course, you don’t have to be this detailed, but this is a good guide for how to determine your world’s climate zones.
But what if your world isn’t like Earth? Let’s look at three types of worlds briefly.
First is the dry world. Most likely, you’ll use arid and semi-arid climates. However, you may have pockets of wetter climate zones around bodies of water. The closer you get to the poles, the climate may change from desert to tundra gradually. And then you may also have to have a more temperate desert in between. This requires you to create new types of climates.
Second is the wet world. Your world may be covered by rainforests. If you have large continents with mountains, I’d probably expect there’d be some dry areas, but not too extensive. The farther you get from the equator, your world may go from tropical rainforest to savanna to temperate rainforest to boreal forest. You might not even have to deal with subarctic or polar climates.
Finally is the oddball of the bunch. A tidally locked planet with a red dwarf star. I’ve discussed this before in the second part of the worldbuilding series. The side that faces the star is incredibly hot and uninhabitable. The side that faces away from the star is incredibly cold and is likely a permanent ice cap. The habitable area is along the terminator. This is where we have some trouble determining what the climate may be like. It’s probably quite windy, as winds would be howling from the hot side to the cold side of the planet. But let’s say it’s not so bad. Basically, you’d go from desert to tropical to temperate to subarctic and to polar in a very short distance. It’s very unlikely there’ll be any great oceans to moderate temperatures, so it’ll be mostly continental. However, no day/night extremes, no seasonal extremes, just the same every day. Mountains would likely get plenty of rain.
There are other factors to consider, as well. One is the axial tilt of your world. More extreme tilts would make more extreme seasons. No tilt would mean no seasons.
What I did
After I drew my world map, I traced it out onto another sheet of paper and started colouring in the climate zones as best as I could. This was long before Wikipedia existed, and I didn’t think to even search the Internet for climate zones, let alone Koppen climate classification. So, I just did the best I could. I made this map:
Pretty crude look, isn’t it? I have desert in yellow, tundra (and ice cap) in white, tropical forest in emerald green, temperate forest in a darker green, grassland in pink, marsh/wetlands in orange, and mountains in brown. This has more to do with vegetation, but it basically is a climate map with the exception of marsh (that’s a habitat, not a climate). What you’ll notice is the vast tropical forests, large grasslands and rather limited amount of desert. You see, Ariadne is in a humid period, though it does have polar caps.
Even though I have created that map, I’d like to redo it with the Koppen climate classification system in mind. It would be more scientifically accurate, and not a simplistic as this.
So, what should you do about climate on your world? It’s up to you. Make it as complex as you want, or keep it simple. I love complexity, as you probably already know. Enjoy mapmaking!
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