The Coriolis effect is a result of earth spinning. Basically because earth spins and has different circumferences at different latitude it pulls air along with it at different speeds. This creates a speed differential in high atmosphere which creates a sort of gear appearance to large currents with each band spinning in alternate directions. Since hurricanes develope in the doldrums on opposite sides of the equator they are on opposite sides of one of these gear shifts. It’s hard to describe in text. Look up atmospheric currents. There’s other factors here but the tldr is they spin with the Coriolis spin of their band in the tropics. This can only happen on a sphere. A stationary disc would not have the circulating currents and diameter differences to create symmetrical currents between hemispheres.
So the Earth rotates west to east. This means that along the equator, the air is moving west to east.
This rotational speed is greatest at the equator, for the same reason the edge of a CD is moving faster than the center. There’s less rotational area as you approach the poles.
So the side of the hurricane facing the equator moves in that same west-to-east direction. The ‘top’ of a hurricane in the southern hemisphere moves west to east, making it rotate clockwise. The ‘bottom’ of a hurricane in the northern hemisphere moves west to east, making it rotate counter-clockwise.
On a flat disc, this wouldn’t happen. The equator would not be the “fastest” place of rotation – that place would be the edge of the disc. So if the Earth was flat, you should see all hurricanes going counter-clockwise.
First things first, in order to define a hemisphere, you must already know that the planet is a sphere. Beyond that, the opposing spin direction is just because of the earth’s rotation. Imagine this: you place two clouds at the equator, one going north, one going south, discounting the earth’s rotation. Now you add the earth’s rotation into the mix. At the equator, they’re traveling much faster relative to the center of the earth than they would at the poles, and this speed is reflected as they go closer towards the poles. They both tend to move faster relative to the ground while they’re still on their trajectory towards a pole. The important thing to note is that while one is traveling north and the other is traveling south, they both tend to accelerate towards the east. The opposite is true if you started your clouds at the poles going towards the equator: they tend to go west due to earth’s rotation. This is because of a lot of factors but it can be generalized to the poles having less of an effect on movement due to rotation and less pressure at the poles.
The closer your are to the equator, the faster your physically moving with the Earth’s rotation. Simple thought experiment proves that — how much distance does someone at the poles travel versus someone on the equator.
That change in speed is continuous, so every degree further away from the equator, you move all much slower.
That means the more extreme ends of a hurricane move westward compared to the center since the rotation of the earth is imparting less momentum on that side, and the reverse is true for the equatorial side.
This net movement imbalance creates counterclockwise northern hurricanes and clockwise Southern hurricanes.
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The Coriolis effect is a result of earth spinning. Basically because earth spins and has different circumferences at different latitude it pulls air along with it at different speeds. This creates a speed differential in high atmosphere which creates a sort of gear appearance to large currents with each band spinning in alternate directions. Since hurricanes develope in the doldrums on opposite sides of the equator they are on opposite sides of one of these gear shifts. It’s hard to describe in text. Look up atmospheric currents. There’s other factors here but the tldr is they spin with the Coriolis spin of their band in the tropics. This can only happen on a sphere. A stationary disc would not have the circulating currents and diameter differences to create symmetrical currents between hemispheres.
So the Earth rotates west to east. This means that along the equator, the air is moving west to east.
This rotational speed is greatest at the equator, for the same reason the edge of a CD is moving faster than the center. There’s less rotational area as you approach the poles.
So the side of the hurricane facing the equator moves in that same west-to-east direction. The ‘top’ of a hurricane in the southern hemisphere moves west to east, making it rotate clockwise. The ‘bottom’ of a hurricane in the northern hemisphere moves west to east, making it rotate counter-clockwise.
On a flat disc, this wouldn’t happen. The equator would not be the “fastest” place of rotation – that place would be the edge of the disc. So if the Earth was flat, you should see all hurricanes going counter-clockwise.
First things first, in order to define a hemisphere, you must already know that the planet is a sphere. Beyond that, the opposing spin direction is just because of the earth’s rotation. Imagine this: you place two clouds at the equator, one going north, one going south, discounting the earth’s rotation. Now you add the earth’s rotation into the mix. At the equator, they’re traveling much faster relative to the center of the earth than they would at the poles, and this speed is reflected as they go closer towards the poles. They both tend to move faster relative to the ground while they’re still on their trajectory towards a pole. The important thing to note is that while one is traveling north and the other is traveling south, they both tend to accelerate towards the east. The opposite is true if you started your clouds at the poles going towards the equator: they tend to go west due to earth’s rotation. This is because of a lot of factors but it can be generalized to the poles having less of an effect on movement due to rotation and less pressure at the poles.
The closer your are to the equator, the faster your physically moving with the Earth’s rotation. Simple thought experiment proves that — how much distance does someone at the poles travel versus someone on the equator.
That change in speed is continuous, so every degree further away from the equator, you move all much slower.
That means the more extreme ends of a hurricane move westward compared to the center since the rotation of the earth is imparting less momentum on that side, and the reverse is true for the equatorial side.
This net movement imbalance creates counterclockwise northern hurricanes and clockwise Southern hurricanes.