Westerlies in southern hemisphere are stronger and persistent than in ...
The Westerlies, anti-trades, or Prevailing Westerlies, are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. These prevailing winds blow from the west to the east, and steer extratropical cyclones in this general manner.
The Westerlies are strongest in the winter hemisphere and times when the pressure is lower over the poles, while they are weakest in the summer hemisphere and when pressures are higher over the poles. The Westerlies are particularly strong, especially in the southern hemisphere, where there is less land in the middle latitudes to cause the flow pattern to amplify, or become more north-south oriented, which slows the Westerlies down. The strongest westerly winds in the middle latitudes can come in the Roaring Forties, between 40 and 50 degrees latitude.
the Earth were a non-rotating planet, solar heating would cause winds across the mid-latitudes to blow in a poleward direction, away from the subtropical ridge. However, the Coriolis effect caused by the rotation of Earth causes winds to steer to the right of what would otherwise be expected across the Northern Hemisphere, and left of what would be expected in the Southern Hemisphere. This is why winds across the Northern Hemisphere tend to blow from the southwest, but they tend to be from the northwest in the Southern Hemisphere.
The Westerlies can be particularly strong, especially in the Southern Hemisphere, where there is less land in the middle latitudes to cause the progression of west to east winds to slow down. In the Southern hemisphere, because of the stormy and cloudy conditions, it is usual to refer to the Westerlies as the Roaring Forties, Furious Fifties and Shrieking Sixties according to the varying degrees of latitude.
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Westerlies in southern hemisphere are stronger and persistent than in ...
Explanation:
The westerlies are prevailing winds from west to east in the middle latitudes between 30° and 60° latitude. They are stronger and persistent in the Southern Hemisphere as compared to the Northern Hemisphere due to the following reasons:
1. Lesser landmass in the Southern Hemisphere: The Southern Hemisphere has lesser landmass as compared to the Northern Hemisphere. The large landmass in the Northern Hemisphere creates more friction, which slows down the westerlies. In contrast, the Southern Hemisphere's open ocean allows the westerlies to blow faster and with greater force.
2. Higher Coriolis force in Southern Hemisphere: The Coriolis force is the apparent force that deflects moving objects, including air, to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The Coriolis force is proportional to the speed of the object and the latitude. Hence, due to the higher latitude of the Southern Hemisphere, the Coriolis force is stronger, which results in faster and stronger westerlies.
Therefore, statement 1 is correct, and statement 2 is incorrect. The lesser landmass in the Southern Hemisphere allows the westerlies to blow faster and stronger, while the higher Coriolis force deflects them to the left, resulting in stronger and persistent westerlies in the Southern Hemisphere.
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