Game of Thrones Theorycraft: the reasons for the (weird) seasons

In Westeros, summer and winter can last for years, even generations, at a time, with seemingly no pattern as to when they start and stop. The elongated seasons are one of the most enduring mysteries of the Song of Ice and Fire universe, and not one we’re going to conclusively solve here—there simply isn’t enough information. We are, however, going to dive into the effects the erratic seasons have on the people of Westeros, explore some theories as to their origin, and forecast how bringing them back into balance could be hugely consequential for our characters.

People in Westeros build their lives around the changing of the seasons. They plan trade routes around autumn storms, stockpile crops to last through the long winter, and in some cases even undergo seasonal migrations (in A Game of Thrones, it’s mentioned that people from the countryside pile into the winter town outside Winterfell come the cold). It’s theorized that the long seasons—particularly the long winters—are the reason Westeros has been stuck in the medieval period for thousands of years. If you spend all your time figuring out how to survive the next winter, the theory goes, you don’t have time to industrialize.

So the long winters have a huge effect on people’s lives. But why do they happen? Why doesn’t Planet Westeros have predictably segmented seasons like we have on Earth?

There are a lot of theories out there, and several of them attempt to explain Westeros’ weather patterns in terms of physical science. As we’ll see later, those explanations are kind of moot, but we’ll look at one of them anyway.

Maesters: keeping the scientific method alive.

Theory: Westeros’ erratic seasons are caused by a wobbly planetary tilt

First, some science talk: Earth revolves around the sun on a slightly tilted axis (a 23.4° offset of the axis, to be exact), meaning that light hits it at slightly different angles depending on where it is in its revolution. At different times throughout the year, the sun’s rays hits certain parts of the planet more directly, resulting in longer days and warmer temperatures. At other times, parts of the Earth’s surface are tilted away from the sun for longer portions of the day, resulting in shorter days and colder temperatures. Bam: seasons.

It’s important to note that, while Earth operates on a slight tilt, it’s a very stable tilt, so the seasons repeat with unfailing regularity. We have our moon to thank for that—it’s disproportionately large compared to other planetary satellites in the solar system, and it anchors our tilt in place. Without the moon, the Earth might wobble on its axis, resulting in unpredictably long, or short, seasons.

Might that be the situation for Planet Westeros? We know from the second episode of the show (“The Kingsroad”) that the planet has at least one moon. If that moon is small or distant, it could be disrupting the planet’s tilt rather than stabilizing it, which could result in the wonky seasons.

It’s also worth noting that, in A Game of Thrones, Doreah tells Daenerys that the situation used to be different. “Once there were two moons in the sky, but one wandered too close to the sun and cracked from the heat.” There’s a strong possibility that Doreah was reciting a myth—she also claimed that dragons emerged from the cracked moon—but myths can sometimes be based in reality. If Planet Westeros did indeed lose one of its moons to some cataclysm, it could have destabilized the planet’s tilt.

But honestly, there’s almost no chance this theory is true, for the simple reason that George R.R. Martin has gone on record as saying that the extended seasons have a fantasy, rather than a scientific, explanation.

Next: So much for science. Bring on the fantasy explanations.