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1. Why don't hurricanes form in the north Atlantic? 2. In the northern hemisphere, do hurricanes move clockwise or counter clockwise? 3. What two celestial object cause the tides on the moon?
Question Date: 2007-05-23
Answer 1:

Hurricanes are known to form in warmer climes simply due to the higher evaporation rates of the water which are the initial source of a hurricane's power. Its basically a large heat engine (similar to the one in your car, but with different fuel) driven by temperature/pressure gradients (differences in temperature/pressure between different places), condensation, and evaporation. If you remove or decrease one of those processes, then the hurricane loses power. In the northern Atlantic, the rates of evaporation generally aren't high enough to get such a storm started.

Hurricanes only exist in the northern hemisphere since by definition they rotate counterclockwise. In the southern hemisphere, they are called typhoons only because they rotate clockwise. Its a silly distinction. They both fall under the category of tropical cyclone, which is probably the more technical term. The reason for this difference is due to an effect called the Coriolis force. it's due to the earth's rotation, and you can observe this effect for yourself if you stand on a fast-spinning merry-go-round in the center and try to walk outwards (these tropical cyclones would equivalently start from the outside and move in, due to the fact that they move towards our north and south poles, but the effect is the same). Youll feel a "force" tugging on you along or opposite to the direction of rotation. Thats the Coriolis force.

I think you're confused about your question here... there are no tides on the moon since there's no water. Tides are (as far as I know) ubiquitously used to describe motions of water due to gravitational bodies. The primary source of our tides on earth is due to the moon. Theres also a weaker effect due to the sun, but it's not nearly as prominent. When you study gravity it will become easier to explain, but basically tides are due to the difference in the force of gravity between two points, not the actual strength of gravity. For instance the sun acts with much more gravity on us than the moon does, but the moon gives us stronger tides than the sun. You can think of it this way: imagine a person pulling in two directions on an object. No matter how strong he is, if his arms are the same strength then the object doesn't move. But if one arm is much stronger than the other, then the object gets pulled in some direction. In that sense, the tides are due to differences in gravity on opposite sides of the earth. The sun's gravity is not too different from one end of the earth to another (even if it's very strong) while the moon's difference is much greater (even if the overall gravity is much weaker).

Answer 2:

Earth and the Sun are large enough and close enough to cause measurable tides on the moon.The Sun is very far away, but it's also very, very large.

Hope this helps! Best wishes...

Answer 3:

1. Hurricanes, indeed all storms, require heat to form. If the water isn't warm enough, they just won't happen. The North Atlantic is quite cold.

2. Air spins counterclockwise around low-pressure regions in the Northern Hemisphere.

3. Everything in the universe induces tides on a given object at some level. On the moon, the two most important tide-influencing objects are (most important) the Earth and (secondarily) the Sun. Of course, there aren't any oceans on the moon to respond to those tides...

Answer 4:

1. Why don't hurricanes form in the north Atlantic?
Hurricanes don't form in the North Atlantic because they require warm sea surface temperatures.

2. In the northern hemisphere, do hurricanes move clockwise or counter clockwise?
Hurricanes spin clockwise in the northern hemisphere and counter-clockwise in the southern hemisphere because of the Coriolis force acting on the rotation of the planet. See this link for an explanation of Coriolis forces (there is an animation that is very helpful): click here

The animation, as it is shown, would represent the northern hemisphere; you can see the black object spinning clockwise. Imagine turning the animation upside-down; the black object would spin counter-clockwise. A similar effect happens to air particles within hurricanes in the Earth's atmosphere, leading to the spin orientation for the hurricane.

3. What two celestial object cause the tides on the moon?
Tides, as typically referred to, are a property of the Earth's oceans. They are a cycle of changes in sea level. Gravitational forces from the sun and the moon affect the ocean tidal cycles on the Earth. Since there is no water on the moon, the moon does not have these sorts of tides. A tide, in a more strict sense, is a periodic gravitational force on a body; these forces can distort the shape of the body (such as the Earth or moon) very slightly. It is actually this type of distortion that leads to the Earth's ocean tides. The two celestial bodies that exert the strongest tidal forces on the moon are the sun and the Earth.

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