In the Southern Hemisphere, the winds of a cyclone blow
- A.clockwise and inwards
- B.anticlockwise and inwards
- C.clockwise and outwards
- D.anticlockwise and outwards
Correct answer
Explanation
The correct answer is A, clockwise and inwards. A cyclone is a low pressure system, so air flows inwards towards the centre, and the Coriolis force deflects moving air to the left in the Southern Hemisphere, which turns that inflow into a clockwise spiral. Option B, anticlockwise and inwards, describes a cyclone of the Northern Hemisphere, where the deflection is to the right; this is the pairing examiners most often swap. Option C, clockwise and outwards, describes an anticyclone of the Northern Hemisphere, since a high pressure system pushes air outwards from its centre. Option D, anticlockwise and outwards, is the Southern Hemisphere anticyclone. The way to hold all four is to settle the pressure first, inwards for a low and outwards for a high, and then apply the hemisphere, right hand deflection in the north and left hand deflection in the south.
Read the full article: Cyclones: Naming, IMD Categories and Warning Stages
Practice Questions
View allA cyclone is known by different names in different parts of the world. In Philippines it is called as _______.
- A.willy-willy
- B.hurricane
- C.typhoon
- D.mango shower
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The Philippines lies in the western North Pacific, and every tropical cyclone of that basin, whether it strikes the Philippines, China or Japan, is called a typhoon.
Read the full explanation →What is the minimum sea surface temperature generally required for a tropical cyclone to form?
- A.About 16.5 degrees Celsius
- B.About 20 degrees Celsius
- C.About 26.5 degrees Celsius
- D.About 36.5 degrees Celsius
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A tropical cyclone runs on the latent heat released when water vapour condenses, so it needs a sea whose surface is at about 26.5 degrees Celsius or warmer, with that warm water reaching down about fifty metres, so that the churning of the sea does not cool the surface.
Read the full explanation →According to the India Meteorological Department, a system is classified as a super cyclonic storm when the sustained wind speed is at least
- A.118 km/h
- B.167 km/h
- C.222 km/h
- D.300 km/h
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The India Meteorological Department puts a system in the highest class, super cyclonic storm, when the sustained wind at its centre reaches 222 km/h, which is 120 knots.
Read the full explanation →In which year did the naming of tropical cyclones in the north Indian Ocean begin?
- A.1999
- B.2004
- C.2013
- D.2018
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The eight countries of the WMO and ESCAP Panel on Tropical Cyclones agreed on a list of names for this basin and began using them in 2004, long after the Atlantic, where naming had been practice for decades.
Read the full explanation →Which body names the tropical cyclones of the north Indian Ocean?
- A.The Regional Specialised Meteorological Centre, New Delhi
- B.The National Disaster Management Authority
- C.The Indian National Centre for Ocean Information Services
- D.The National Centre for Medium Range Weather Forecasting
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The names themselves are contributed by the thirteen member countries of the panel, but the centre at New Delhi, which the India Meteorological Department runs, takes the next name from the list, announces it when a deep depression strengthens into a cyclonic storm, and issues advisories to all the member…
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