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Are there more hurricanes in the northern hemisphere of the Earth, than in the South? If this is true, can you tell me why?
Question Date: 2011-11-13
Answer 1:

In general twice as many hurricanes form in the Northern Hemisphere than in the Southern Hemisphere. In fact, only one hurricane-strenghth storm, Cyclone Catarina in May 2004, has been recorded in Southern Atlantic.

In the Southern Hemisphere hurricanes are called cyclones and in the Eastern Hemisphere hurricanes are called typhoons. Hurricanes, cyclones, and typhoons, are all the same thing (known together as tropical cyclones) it just depends on where they are formed the Northern Hemisphere, Southern Hemisphere, or Eastern Hemisphere respectively.

The reason why more hurricanes form in the Northern Hemisphere is that the conditions favorable to hurricane development are more prevalent in the Northern Hemisphere than the Southern Hemisphere. These conditions include: warm ocean water and low wind shear. In the Southern Hemisphere Ocean temperatures are cooler and there is greater winds and hence wind shear that prevent formation of the cyclone.

The Southern Hemisphere oceans are cooler mainly because there is more ocean to warm in the Southern Hemisphere and partly due to the large Antarctic Ice Sheet in the south. Ocean water takes a lot more energy to heat than does the land surface. If you look at a map, note how much more land is in the Northern Hemisphere than the Southern Hemisphere.

The winds are stronger in the South because the Northern Hemisphere is generally warmer; the larger temperature change with distance (or temperature gradient) causes winds to be stronger. The stronger winds cause what is known as wind shear that prevents the development of the cyclone. Shear is a fancy way of describing the force 'felt' in between two surfaces (e.g. the force you feel when rubbing your hands together). Thus wind shear is produced as winds blow preventing a tropical cyclone from developing.

Answer 2:

Yes, there are generally more hurricanes in the northern hemisphere than in the south.There are a few reasons for this:

Hurricanes need 3 main ingredients in order to form: warm ocean water, low air pressure, and low wind shear. These ingredients are readily available in the tropical waters of the northern hemisphere, especially in the warm, shallow Caribbean Ocean and Gulf of Mexico, as well as the central Pacific Ocean. These ingredients are more rare in the southern hemisphere. The Atlantic Ocean, for example, is much colder in the southern hemisphere. There is also more wind shear, which tends to tear storms apart before they can get organized into a hurricane.

Answer 3:

Wow, good question! I don't know, but I would suspect that there are actually more hurricanes in the southern hemisphere, because a larger fraction of the southern hemisphere is ocean, and hurricanes draw their energy from warm seawater. We hear about northern hemisphere hurricanes more because there is more land in the northern hemisphere, and people live on land, so any hurricane in the northern hemisphere is thus a lot more likely to hit something inhabited and cause damage.

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