A summary of the seasons
Hey Blog! This week it snowed for the first time this winter, and therefore I thought I’d talk about why it sometimes snows and sometimes is 40° – this is a brief summary of the seasons!
Unless you are currently straddling the equator in which case you have two seasons at once (technically speaking…), one on each side, or living in London, at which point you reputedly experience four seasons in one day; you probably have a general idea of the seasons. Either Spring, Summer, Autumn and Winter, or else Wet and Dry – depending on whether you live in the tropics or in temperate zones. Because I live in England, I usually experience the former, so I’ll tell you about that.
The whole business with seasons is all about Earth’s tilt. This is an odd cosmic fact – the Earth is not level, right way up, or spinning flat like a top, it is in fact slightly tilted, spinning steadily but at an odd angle. If you mark a ball on opposite sides and hold it on these dots at an angle, then move around it, you will see that the top half and bottom half get closer and then further away, depending on the angle you are to the tilt. This is exactly what happens with Earth – parts of the planet get alternately closer and farther away – but the difference in distance is not the primary factor. Instead, it is light.
You might think light is not too hot, not enough to cause the seasons, surely; but this is not just an LED bulb in the ceiling. This is cosmic radiation, made from fusing hydrogen into helium and heavier elements in the heart of a star – our sun – and releasing enormous amounts of energy through nuclear fusion, a process which relies on a number of Scientific Laws. This energy is released as radiation – the electromagnetic spectrum, which is basically all the wavelengths of light, even those we can’t see. While most of the harmful, high-power radiation is blocked by our wonderful atmosphere, the rest shines upon our planet and powers the world.
This light, combined with the tilt, combined with the atmosphere, means during summer, when part of the earth is pointing towards the sun, the light hits it full on. Passing through a thinner layer of atmosphere means that the wave still heats Earth when it reaches it; but on the other side, where the atmosphere is thicker, the light takes longer to pass and looses more energy, meaning the earth is cooler there. This means while it’s summer in one hemisphere, it’s winter in the other, and when it’s spring in one, it’s autumn in the other. But what about the poles? Because they are so far north and south, they have such a thick atmosphere separating them and the sun, so they are always cold. Even worse, the sun is hidden behind the rest of the earth for half the year, meaning once winter comes, the poles will not see the sun for six months. Correspondingly, the other pole will not see the sun set for those six months!
While this explains the seasons, it doesn’t explain the weather. This is more tricky. Weather is ultimately based on the wind, and that is caused by two things – heat and Earth’s spin. Because Earth is always spinning, it causes a disturbance around it in the atmosphere. This is called the Coriolis Force, and is what causes hurricanes. It is rumoured to be what causes honey to twizzle and the water to go down the toilet in a spiral – however, this is incorrect, because there simply isn’t enough time or material for the Coriolis Force to take effect in these instances. Heat, on the other hand, is once more caused by the sun – the driving engine for Earth’s systems – and is related to pressure. Once a body of air has got hot, it rises, thus allowing cold air to come and take its place. This inflow is the other cause of wind. Such a lot for weather forecasters to take into account! Subtle changes such as these are what cause both snow and heatwaves, which just shows how fine the balance truly is!
Seasonal change means that people and animals around the world experience different weather and climate at different times of the year, which means they follow the seasonal cycle. Some people see this cycle as a reflection of life, others as a reflection of time. I see it as just how nature is, naturally, and we shouldn’t mess with it – putting too many chemicals into the air and changing the climate will ruin this balance, on which everything depends, so if there is one lesson to learn from nature, it is not to change the balance that has worked for millions of years – nature has tested and retested, and is far stronger than mankind. Respect nature!
Currently, the Northen Hemisphere is going into winter, which means it’s time to get the woolly jumpers out and put on an extra pair of socks. Oh, and drink lots of hot chocolate, stoke up the fire, and get ready for Christmas or whichever midwinter festival you choose to celebrate. Have fun!

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