I looked this up and it said the Coriolis effect so I looked that up and I have no clue what it’s talking about…
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There’s the Newton thing about objects moving in a straight line unless another force interferes. That’s in play here.
The earth is about 24,000 miles around, so it moves at 1000 miles per hour at the equator. A object moving due north from the equator would have a starting eastward motion equal to the equator speed. Ignore air friction for the moment, please.
Now let’s say that object, a parcel of air (some arbitrary volume) moves north to 45 degrees north. The size of the earth gets smaller as you move toward the poles, so the ground speed is only 700 miles per hour now. Keep going to the North Pole and it’s zero! The parcel, because it moves north from the equator is moving east faster than the ground under it is moving east. The effect of this is the track of the parcel turns toward the right.
Now let the parcel move south from 45 North — it’s now slower than the ground speed at lower latitudes, so it turns right again as it travels!
This direction change is called the Coriolis Effect. In the Northern Hemisphere, the effect causes a moving parcel to turn right in the long run. In the Southern Hemisphere, it’s a left turn.
Oh! you say — what about east and west? A straight line on a sphere is called a Great Circle path. At the equator, it’s a straight line parallel to the equator. At the poles, it’s any of the longitude lines going north and south. But, if you’re at, say 45 north, your great circle will eventually cross the equator 90 degrees east or west of your position. And, oops! you’re moving toward the equator (south) again, so it turns to the right. Left, in the Southern Hemisphere.
Now, hurricanes: High pressure systems are regions of descending air parcels heaped up over an area. The heap is what causes the higher pressure. But, air is fluid, so it drains from that area, and in moving away, Coriolis makes it turn right (Northern Hemi), so the High overall has clockwise flow. And opposite in the Southern Hemi, of course.
A Low pressure system contains rising air. The rising air is replaced by air moving toward it from the outside, again because it’s a fluid, and the atmosphere likes balance. But — Coriolis is too weak compared to the forces moving air toward the center of the Low, so it spins around the Low as it moves toward the center. Thus, counter clockwise flow. (Opposite in SH)
A hurricane is a special type of really, really wound up Low pressure system, so the air flowing into and around it can get up to hundreds of MPH/ KPH toward the center.
Oh – where does the air go? Out the top! Eventually the rising air runs into a temperature change from the lower atmosphere (Troposphere) to the next layer (Stratosphere) and moves out and away from the center. The temperature changes stops it from getting any higher, mostly.
Same with thunderstorms. Moist air in the bottom, then up to the feathery tops at and under the Stratosphere. And a hurricane/typhoon/cyclone is a type of organization of thunderstorms.
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