Winds,Breeze and Cyclones

  • Westerlies: These are winds which blow from about 40° North to the Artic circle and from about 35° South to the Antarctic of the direction in which they blow. In the Southern hemisphere, they blow in a North westerly direction. In the Northern hemi-sphere, they blow in the South westerly direction.
  • Polar Winds: These are easterly winds which blow from the polar regions towards the Equator.
  • Trade Winds: The rays of the sun fall vertically on the Equator with the result that the atmospheric pressure there becomes low due to the air becoming hot. The pressure in high near 30° N and 30°S. Since winds blow from high pressure to low pressure, winds from these latitudes blow towards the equator and trade winds are caused.
  • Land breeze: At night land masses cool more quickly than sea, therefore, an air stream passes from the land to the sea. It is called land breeze.
  • Sea breeze: In the day time, the land is hotter than the sea. The air over land rises and is replaced by a cool breeze from the sea. It is called sea breeze.
  • It is a system of very low pressure in the centre surrounded by increasingly high pressure outwards. In this, the winds blows in a circular manner in
  1.  Anticlockwise direction in Northern Hemisphere.
  2. Clockwise direction in Southern Hemisphere.
  • These are known as : Cyclones in the Indian Ocean; Hurricanes in the Caribbean Islands; Typhoons in the China Sea; Willy-Willies in the North West Australia; Tornadoes in coastal US.