Earlier today, or should I say last night, I posted the fourth part of my worldbuilding series of posts. It was a big one. But it’s well worth the read if you’re interested in creating your own world for fantasy or science fiction.
I’d like to direct your attention to the menu at the top of the page. Where it says Writing, there are menu options under that heading, and one of them is Worldbuilding. That’ll take you to the main Worldbuilding page where I’ll be keeping a list of all the posts related to creating a fictional world. So far, it’s been pretty scientific, but the human side of things will be coming soon.
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!
For more posts on worldbuilding, please check out this page.
It’s been a while since I’ve done any posts about worldbuilding, but I’ll be resuming them soon. I don’t know how many posts there will be in total, but expect a lot. Worldbuilding can be as complex or as simple as you want, but want to be thorough and give you as much information as I can.
Here’s what you can expect:
Mapmaking (climate and ecosystems) – This will complete the scientific part of worldbuilding for now. Climate and ecosystems are linked, so I’ll do them together.
Flora – I’ll discuss making plants here.
Fauna – I’ll discuss making animals and also talk about evolution.
Other life – This will include the microbes, and anything else that may be considered life, including the exotic.
Mapmaking (political) – Drawing country boundaries.
Cities and Towns – Where do you place the cities and towns? When you create a country, you should include a capital, principal cities, and towns.
Designing communities – This is looking into how a community is created, including commercial districts, industry, residential areas, and agriculture.
Designing communities – Infrastructure. This includes the basics to keep a community running, including roads, waterworks, electricity, and so on.
This is what I have planned so far. I will also go more in depth with agriculture, government, industry, transportation, culture, religion, history, war, and more. As you can see, this is a huge topic.
Here’s where the fun starts with your world. I assume you’ve chosen the type of world to create, whether it’s Earth-like, a waterworld, or a dry world. All of these need a map. This section is more important for fantasy worlds, though it is quite useful for science fiction worlds if you’re creating a whole world.
Making a Basic Physical Map
To start off, a simple map will do. Make the continents first. But don’t just make them blobs. They need intricate coastlines. The more complex, the more realistic. Look at a map of Earth. Take a look at coastal regions and you’ll see that they’re not straight lines. They’re not curves. They’re very organic looking with lots of inlets and peninsulas. That’s what you want to draw.
What you need to do next is add the mountain ranges, lakes, and rivers. Keep in mind that large mountain ranges form continental divides. The rivers should flow from the mountains, not cut through an entire mountain range from one side to the other. Mountains aren’t random, either. What is useful is to create a map showing the tectonic plates, and show the direction of movement of each plate. This will allow you to determine where the mountain ranges go, as well as pinpoint the seismically active regions. You can indicate where volcanoes are in this step, as well as the mountains.
A Fantasy Reader has an index of maps that shows a long list of fantasy novel maps. Definitely worth going through for some ideas about style. The style is up to you. The easiest is to use a bunch of triangles for the mountains. Even the best did it.
The map gives you a lot of possibilities for stories, especially if you’re writing a long series. It also gives you an image of what the world is like. It’s a very powerful tool. I love looking at maps in fantasy novels. I love making them, too.
What I Did
For Ariadne, I did just what I said above. However, I drew the tectonic plates map after I drew the mountains. I just imagined how they would be arranged with the mountains already drawn. But this gave me the idea of where to put the volcanoes and which areas are prone to earthquakes. I also included some hotspot volcanoes, similar to Hawaii.
I’ve posted the above image before, and this is my work in progress, the map of Ariadne I’m digitizing. Whether you do the map on paper or computer is up to you. I prefer doing it on paper.
My map contains four continents and two major oceans with some large bays. There are also ice caps, but I’ll talk about this on a later mapmaking topic when we deal with climate and ecosystems. To read more about Ariadne’s mapmaking process, please check out this post.
Now that we have a star chosen, we need to decide the properties of the planet. There’s a large variety of planet types to choose from, but we need to make sure of one thing, it has to be in a habitable region in the system, or the Goldilocks Zone. But that’s not all. There’s a lot to consider.
Creating Your Planet
First, let’s figure out where the planet is. It needs to be far enough from the star so that it isn’t incredibly hot, and it has to be close enough so it isn’t completely frozen. This area is the Goldilocks Zone. I wrote about creating a calendar for a hypothetical planet in this post recently, and it uses the same equation.
D = (Ts^2Rs/2Tp^2)((1-a)/(1-τ/2))^1/2
D is the distance of the planet from the star. Ts is the temperature of the star (you can figure this out with a Wikipedia search of your chosen star). Rs is the radius of the star (again, use Wikipedia). The other two variables are what you assign yourself. First is a, or the albedo of the planet. An albedo of 1 means that all light is reflected, such as an ice planet. An albedo of 0 means no light is reflected, which is pretty much impossible. The Earth is around 0.37. You can fudge with that number, but the higher you go, the colder it is, the lower you go, the warmer it is. A forest can be anywhere from 0.09 to 0.18. Grass is 0.25. Desert sand is 0.40. Now, if there were no atmosphere, a desert would be colder than a forest, but that’s not the way it works on Earth. That’s where the other term comes in, τ. This is the optical depth of the atmosphere. If it’s a higher number, it’s hotter, if it’s a lower number, its colder. Basically, a high number implies a stronger greenhouse effect. Venus has a very high optical depth. The Earth’s is about 0.6. Finally, we have Tp, or the temperature of the planet. This is the key number you want to set. If you want an Earth-like world, set it at about 288 Kelvin (or about 15 degrees Celsius). If you want a hot planet, maybe 313 Kelvin is fine. A cold planet could be 273 Kelvin. With these numbers, you can choose a range of orbits for your planet.
Now, putting aside the mathematical part, we have to choose a size for the planet.
The above chart shows what planets have been discovered by Kepler. It’s apparent that Super Earths and Earth-size planets are very common. Obviously, an Earth-sized planet is ideal if you want an Earth-like world to create. But the Super Earths create an interesting possibility. However, there’ll be higher gravity, and you’ll possibly have a thicker atmosphere. But that’s not necessarily true. What you’ll also get with a larger planet is much more land to play with. Imagine the exploration possibilities. There are some other effects of having a Super Earth, though. Mountains will be smaller, ocean waves will be smaller, animals will likely have thicker and stronger legs, people will become stockier. A planet smaller than the Earth will have opposite effects. Mountains are taller, though plate tectonics is less likely. Possibly no earthquakes or volcanic activity. This can be a problem with maintaining an atmosphere that can trap heat, unless there’s a healthy plant cover. The core of the planet will cool more quickly, and a smaller magnetic field could make it a less habitable planet. People would also have problems with maintaining calcium in the bones, and may be unable to return to Earth. But if it’s just a bit smaller, it should be no problem.
The surface of the planet is another thing to consider. How much land will you have? Earth is around 25% land. Do you want more land and less water? Sure, go ahead. It’ll likely be a more arid planet with more extreme summers and winters. Or do you want more water? Then you’ll have a more moderate climate, but expect plenty of tropical cyclones.
But what if your planet is a moon of a gas giant, like Pandora in Avatar? Well, you can go ahead and do that, but if you want scientific accuracy, keep in mind that the tides on the moon will be quite high if it’s close to the planet. This will mean very strong tides, making any coastal regions very dangerous to live in. Also, even if the moon is farther from the planet, it’s likely to be tidally locked. This means one side of the moon will always face the planet. A larger orbit means longer days. You could have a world with incredibly long days and nights. The Earth’s moon has days and nights of 14 days long. For a habitable world, this would create an interesting way of life, I would think.
You can take as much or as little of this advice as you like. Remember, it’s fiction. For a fantasy world, you don’t have to think about this part, unless you want to.
What I did
Ariadne turned out to be in a very favourable position around Beta Comae Berenices. I took a temperature of 288 Kelvin, an albedo of 0.37, and an optical depth of 0.6 to produce a very Earth-like planet. It’s slightly larger than Earth at 1.028 its mass. It has a roughly Earth-like ratio of land to water, consisting of one very large continent and three smaller continents. It has polar ice caps. Thanks to the world being in a rather humid period, there are only two major deserts and a lot of tropical rainforests. It’s a geologically active world with plenty of volcanoes and earthquakes. The volcanism is a bit more than Earth due to its younger age. Although I didn’t touch on moons of planets in the above section, Ariadne has two moons, one closer and larger than our Moon, and the other farther and much smaller. There will be significant tides, of course.
Next time, we’ll take a much closer look at the surface of the world.
This is the first post in a series of posts in which I will describe my method to creating a new world for science fiction. Back in November, I described how to colonise a world, but this is different. While that is more about the process of a world being selected and colonised, this is about how to create the world.
Choosing a Star
I’m not even going to look at the planet to begin with. What we need for a plausible habitable world is a star that can host it. I’ll look at the various types of stars and their suitability to host a habitable world.
First of all, we can safely say that giant and supergiant stars are not suitable. They are very short-lived, and while they used to be smaller stars that were stable, their giant size has swallowed up any planets that would have been habitable. More distant planets may have become habitable, but with a giant star’s unstable atmosphere and impending destruction, it’s not a good idea to use these stars, unless your story has some kind of outpost on an outer planet. But I want to discuss habitable planets that you can breathe the atmosphere.
Neutron stars are also out. The radiation is incredibly strong and would kill everything. But planets do exist around neutron stars.
White dwarf stars are the dead remnant of regular main sequence stars. Our sun will become one in a few billion years. After a giant star has expelled its atmosphere and collapses into a white dwarf, it can form new planets close in, as there’s a lot of debris from the former star. However, the habitable zone is so close to the star that it would experience very strong tides and make the orbit potentially unstable. This doesn’t mean that a white dwarf can’t support a habitable planet. I would suggest that it’s unlikely, though. It is possible, so go ahead and make your planet’s star a white dwarf if you like.
The best kinds of stars to use are main sequence stars. There are several stellar types, and they’re nice stable stars undergoing hydrogen fusion in the core. They range from very hot to very cool, with spectral types O B A F G K M.
O, B, and A type stars are very hot. They’re also large. They have a habitable zone farther from the star, but the problem with a habitable planet developing is that it doesn’t have much time. These stars are quite short-lived. O stars are the most massive, and they burn through their hydrogen very quickly. A planet would have no time to develop a habitable atmosphere. These stars are only around for a few million years before going supernova. B type stars aren’t much better. They are also extremely hot and massive, and they’ll go supernova in a few million years, as well. A type stars are around for a few hundred million years. They’re a safer bet, but unlikely to develop much in the way of life. There have been planets found around these stars, but as it takes time for life to evolve, and for a breathable atmosphere to develop, it would not be a good place for intelligent alien life or a human colony to easily be established. O, B, and A type stars represent less than 1% of the stars, so they are not common.
The best types of stars for more Earth-like planets would be F, G, and K type stars. The Sun is a G2 star, which means it’s slightly cooler and smaller than an F type star, but quite close to that type. F type stars have a shorter life than G type stars, but should have enough time for life to develop and to have a habitable planet. These are good stars. Of course, G type stars are suitable. K type stars are smaller and cooler than our sun, so have a habitable zone closer to the star. However, they are around for a lot longer than G stars. The year may be shorter, but the lifespan of a planet is far longer. Excellent candidate for a planet.
Finally, we have the M type star. These are red dwarf stars, and make up 76% of the stars in our galaxy. As they are the most common type of star, they are also the most likely to find planets. The habitable zone is very close to the star. This poses a problem. As it’s so close to the star, the planet could be tidally locked. One side is always facing the star, while the other is facing away. The sunlit side is always hot, while the dark side is always incredibly cold. Atmospheric circulation could lessen this a bit, but expect both extremes to be uninhabitable. The fringe around the terminator (the area where you have a permanent sunset/sunrise) could be habitable. This would give a very interesting environment for life. No day and night cycle. The life that would evolve there would be quite different. For a human colony, it’s quite feasible. Just don’t venture too far into the sunlit side, and be prepared for deadly cold in the night side.
F, G, and K main sequence stars would be the best, but M type red dwarfs would make a very interesting setting for a science fiction story. Any other kinds of stars are risky or even suicidal (neutron stars).
What I did
In the case of Ariadne, I chose a G type star that was relatively close to us, Beta Comae Berenices. It’s 29.78 light years away, and is a G0 spectral type star. It’s slightly hotter and larger than the Sun, but it has a similar habitable zone as the Sun. It is about 1.5 billion years younger than the Sun, though. We don’t know enough about how evolution happens on other planets, so it’s quite possible it could be faster or slower. At an age of 3 billion years, our own planet Earth only had simple multicellular organisms and an atmosphere that wasn’t breathable, only 1% of today’s level of oxygen. But who’s to say that it can’t happen faster on other planets? On Ariadne, it was faster. The scientists who studied the planet found that oxygen levels were comparable to the Earth’s so it was deemed a very good candidate for colonisation. A space probe confirmed that. Complex life was there, but this is for a later discussion on world-building.
The official blog of Jay Dee Archer. Exploring new worlds, real and fictional.