With reference to a tropical cyclone, consider the following statements.

1. Cyclones are intensified by the energy released during condensation in cumulonimbus clouds.

2. Minimum wind speed is attained in the eye-wall region. 

Which of the following statements given above is/are correct?

The correct answer is 1 only.

Important Points

• A mature tropical cyclone is characterized by the strong spirally circulating wind around the centre, called the eye.
  • The eye is a region of calm with subsiding air.
  • Around the eye is the eye-wall, where there is a strong spiralling ascent of air to the greater height reaching the tropopause.
  • The wind reaches maximum velocity in this region, reaching as high as 250 km per hour. Hence statement 2 is not correct.
  • Torrential rain occurs here.
  • From the eyewall, rain bands may radiate and trains of cumulus and cumulonimbus clouds may drift into the outer region.

Key Points

• The diameter of the storm over the Bay of Bengal, Arabian Sea, and the Indian ocean is between 600 - 1200 km.
• The system moves slowly about 300 - 500 km per day.
• The cyclone creates storm surges and they inundate the coastal low lands.
  • The storm peters out on the land.
• The energy that intensifies the storm, comes from the latent heat released during the condensation process in the towering cumulonimbus clouds. Hence, statement 1 is correct.