Consider the following statements:

1. Jet streams occur in the Northern Hemisphere only.

2. Only some cyclones develop an eye.

3. The temperature inside the eye of a cyclone is nearly 10°C lesser than that of the surroundings.

Which of the statements given above is/are correct?

Question

Question

This question was previously asked in

UPSC Civil Services Exam (Prelims) GS Official Paper-I (Held On: 2020)

Answer 1

The correct answer is option 3.

Key Points

Jet streams occur in both the Northern and Southern Hemispheres. Hence statement 1 is not correct.
Extra-tropical cyclones may not always have an eye, whereas mostly mature storms have well-developed eyes.
- Rapidly intensifying storms may develop an extremely small, clear, and circular eye, sometimes referred to as a pinhole eye. Hence statement 2 is correct.
It is warmer and not colder inside the eye of the tropical cyclone.
- The warmer temperature is what drives the storm. Hence statement 3 is not correct.

Additional Information

Jet Stream
- Jet streams are the strong air streams present in the upper troposphere.
- They are relatively narrow belts of swift-moving winds having velocity in the range of 100km/hr to 900km/hr.
- Jet streams follow curved and meandering path and such path is because of Coriolis effect
- And due to the tendency of large scale system to conserve the angular momentum.
- They are very strong winds.

jet stream1

Conditions to form tropical cyclone
- Large sea surface with a temperature higher than 27° C.
- Presence of the Coriolis force enough to create a cyclonic vortex.
- Small variations in the vertical wind speed.
- A pre-existing weak low-pressure area or low-level-cyclonic circulation.
- Upper divergence above the sea level system.

cyclone