The seasons on Roshar

[Horatio Spifflewicket]

So, I am listening to the audiobook for WoK, and was listening to the part near the beginning when Kaladin is in the slave wagons and hopes that spring will come again, with the narrational aside that the seasons were unpredictable. This got me to thinking: how could seasons be unpredictable?

On earth, the distance from the sun and the tilt of the Earth's rotational axis combine to give us seasons. What could be going on for Roshar to be having a random (to Kaladin) distribution of distances from the sun?

My first thought is that perhaps Roshar orbits some sort of binary star system. (Perhaps locked in such a way as to only show one of the two suns at a time, but the differing distances causing irregular (but maybe predictable through math by stormwardens) seasons.

This may also explain Braize, as it could be getting both suns, making it a place of fire and heat and eternal day.

Thoughts?

[Surgebound Rainspren]

I think that there's merit in this idea

It says some where in way of kings there are two suns in the sky. 

[RShara]

Iirc, it's because Roshar doesn't really have much of an axial tilt, so the seasons are even, and are largely determined by the highstorms, their frequency, etc.

[WeiryWriter]

There is WoB on this that I will try to find, basically Roshar has no axial-tilt so it has no seasonal variation.  The "seasons" that are mentioned are more of a translation quirk, i.e. Rosharan "winter" is a period of colder weather, "summer" is a period of warmer weather.
 
@Surgebound Rainspren, would you mind finding a reference for that? I do not recall anything like that.
 
Edit: Found it! Really didn't take that long.  From Writing Excuses Season 9 Episode 23
 

One of the things that the person brought up is that in the Stormlight Archives, we have a planet without axial tilt and seasons don't happen the way that we imagine them on our planet. To them, when the... A season happens is oh, it got cold for a little while. It's winter now for a few weeks. Then when it's not cold anymore, it is not winter and now we're calling it spring. This is a translation effect that I put... That I said, "How am I going to get this across?" Well, to a person speaking English, they would call winter the cold time. So I'm going to translate what they say as the cold patch as winter. I did this to make it jarring, to... Then I made it incidental. These are the two things. It's mentioned incidentally, I did not make it a plot point. I made it just something that they talk about so when they say, "Oh, it looks like winter is going to be here for a few weeks. I hope that spring comes again in a couple of weeks." When it does, they're like, "Oh, good." When it lapses back in the winter, people who are paying attention are like, "This is bizarre. I don't understand this. But this is how it works." That worked really well in the Stormlight Archives because those people who really know about seasons and weather and things like this say, "oh, I know the astronomy of what's happening with this world. That is cool." For everyone else, is just a bizarre aspect of the world. It doesn't influence the plot in a major way, and you just accept it for what it is.

 
(link to transcript)

 

Edit 2: On a sidenote, distance from the sun really has a negligible effect on the seasons, it is entirely based on axial tilt.  For example, at aphelion (when the Earth is the farthest from the sun) the Northern hemisphere is in the middle of summer, at perihelion (when Earth is closest to the sun) the Northern hemisphere is in the middle of winter.

[Horatio Spifflewicket]

Well, darn, I thought I had something there.

I wonder if it is even possible to have a planet orbiting a binary star in the way I was thinking. I will have to take the idea for my own, then.

[SirenKing]

@ RShara - thanks, I'd wondered about this as well.

 

@ Horatio - As near as I understand it, a binary star systems is theoretically possible, but also short-lived. The orbits between masses begin to decay and the larger star (vampire star) eats the smaller mass.

 

As far as habitable planets within a binary system, I thought it was basically impossible, but then I did some research:

http://en.wikipedia.org/wiki/Binary_star#Planets

Turns out that (supposedly) 50-60% of binary systems are capable of supporting life, given that there is a terrestrial mass with the right make-up and orbit.

 

So yes, your idea is plausible.

 

I learned something new today...

Edited September 5, 2014 by SirenKing

[king of nowhere]

I wonder if it is even possible to have a planet orbiting a binary star in the way I was thinking. I will have to take the idea for my own, then.

Roshar is not a binary system, and the reasons for season unpredictability are already explained by others. Though I wonder, since air and water currents play a major effect in the climate, if they would, on a planet without axial tilt, bring seasons with some predictability. many such currents on our planet are seasonal, like the monsoons, but then again, they are seasonal because of axial tilt and its consequences on solar irradiation. I guess if we really found a planet with negligible axial tilt it would be a good study fro climatologists.

 

As for a planet on a binary star, I remember reading a few months ago that one such planet was found. No idea if that kind of orbit would be stable in the long period, but if it was - and if the orbit didn't cause it to have too big thermal excursions - then I'd see no reason why such a planet could not have life.

[SirenKing]

Though I wonder, since air and water currents play a major effect in the climate, if they would, on a planet without axial tilt, bring seasons with some predictability.

I wondered the same thing. My two cents would be that air and water, plus plant life and the slow tidal shift caused by the two stars, would all have patterns. In theory, it would be possible to predict weather changes, though to an ancient civ it would prove very difficult.

[potato]

My theory is a binary planet system. The Tranquiline Halls and the remains of a society destroyed by Odium are on the twin.

Edit: I think there would be some note of the second sun, narrative or otherwise.

Edited November 4, 2014 by potato

[king of nowhere]

I wondered the same thing. My two cents would be that air and water, plus plant life and the slow tidal shift caused by the two stars, would all have patterns. In theory, it would be possible to predict weather changes, though to an ancient civ it would prove very difficult.

where do youu get the idea of two stars? the roshar system has only one star. if there were two, the book would mention it somewhere. they certainly would not have the normal day-night cycle.

[SirenKing]

Lol, I know that Roshar isn't a binary system. Roshar only has a shallow axial tilt, meaning that seasons are more subtle.

 

My 'two suns' bit was either a slip of the tongue that probably came about because I was thinking about two things at once, or I misread your original post. The rest of the reply made sense, though.