Planetary Temperature and Seasonal Variations

Credit: Susan Shankar

Hello and welcome to my world building blog!

Today, I will be discussing Planetary Temperature and Seasonal Variations taken from the accessary book for Advanced Dungeons & Dragons: World Builder's Guidebook by Richard Baker, and published by TSR Ltd in 1996.

The climatology of a planet is important because it affects the entire planet.  Depending on what kind of campaign you want to run, there are five different categories you can choose from: arctic, sub-arctic, temperate, sub-tropical, and tropical.

The Planetary Temperature will dictated which region of the world your campaign will be set.  Here is an passage from the book:

"Mean Planetary Temperature:  If the Earth orbited the sun at the distance that Mars does, the planet would be extremely cold.  On Mars, daytime temperatures rarely approach the freezing point of water.  The Earth would be in somewhat better shape due to its thicker blanket of atmosphere and increased ability to trap heat, but even equatorial regions would be sub-arctic, at best.  You can create an unusually warm or cold campaign world, and adjust the climatic bands to match."

If you remember last week's blog entry, one of my World Hooks was a desert.  I imagined my campaign to take place in a sandy desert setting, but, the frozen tundra is a desert, as well.  Having said that, my random generator chose Freezing as the Planetary Temperature.  A note from the book:  "Freezing:  All climate bands are two steps colder than normal; the poles are uninhabitable."  If the poles are uninhabitable, that would mean the arctic, sub-artic, and temperate regions are pushed closer to the equator of the planet.  There are no sub-tropical or tropical regions. for this world.  That doesn't mean that the poles can't be explored with the proper equipment, of course.  According to the book:

"Uninhabitable:  The conditions are simply too hot or too cold for unprotected humans to survive.  Areas that are too hot may range from 150° F to 200° F or more, while areas that are too cold rarely climb above -150° F.  The Earth does not possess truly uninhabitable terrain, but large portions of Mars could be considered uninhabitably cold."

Putting all this together, I could still set my campaign inside of the temperate region.  Although, it would be more interesting to set it in a colder region, somewhere in the sub-artic, but closer to the artic.

The Seasonal Variations of a planet is dependent on its tilt and rotation.  According to the World Builder's Guidebook:

"Earth's seasons are created by a slight axial tilt to its rotation.  From March 21st to June 21st, the north pole is actually closer to the sun than the south pole because the Earth is tilted in that direction.  As the Earth's orbit carries it around the sun, it still leans the same way; in wintertime, when the Earth is on the opposite side of the sun, the north pole is farther from the sun than the South Pole.  This increases or decreases the amount of sunlight each hemisphere receives at different times of year.  In summer, the northern hemisphere absorbs more solar energy, generating warmer weather and longer days.  In the tropics, seasonal variations are almost meaningless because the equatorial regions receive about the same amount of sunlight all year long."

This is all scientific, and your fantasy campaign does not have to abide by these rules.  The explanation is to give you an idea of how things work.

My random generator rolled up Moderate as the Seasonal Variation.  The book's description is:  "Moderate:  The seasons have a variation similar to Earth's.  The arctic circle is located at the border of the arctic and sub-arctic climate bands (about 23° from the Earth's poles)."  Since my setting is a freezing planet, that would move the artic circle quite closer to the equator.  That doesn't change where my desert setting will be located, it gives me an idea that it's located near the artic circle.  Think of it the climate as being like that of southern Greenland, northern Sweden, or the middle of Alaska; summers are cool, but the winters will be frigid.

Putting is together, so far, I have a pretty good idea about what my campaign setting is going to look like.  A community had settled in a desert region bordering the arctic circle where ruins hold fantastic wealth, magic, and hidden danger, but are used and protected by an evil religion or cult worshiping a dangerous deity.

I hope you are enjoying this little journey of mine through world building and creativity.

Next week, we'll go through forming a kingdom for this frozen desert world, complete with cultural characteristics, government forms, and kingdom size.

I hope you enjoyed the read, and until next time, thanks for reading.