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• There are distinctly identifiable zones of 
homogeneous horizontal pressure regimes 
or ‘pressure belts’. On the earth’s surface, there 
are in all seven pressure belts.
• The seven pressure belts are :
• equatorial low,
• the sub-tropical highs,
• the sub-polar lows, and
• the polar highs.
Page 2


• There are distinctly identifiable zones of 
homogeneous horizontal pressure regimes 
or ‘pressure belts’. On the earth’s surface, there 
are in all seven pressure belts.
• The seven pressure belts are :
• equatorial low,
• the sub-tropical highs,
• the sub-polar lows, and
• the polar highs.
Equatorial Low Pressure Belt or ‘Doldrums’
• Lies between 10°N and 10°S 
latitudes.
• Width may vary between 5°N and 5°S 
and 20°N and 20°S.
• This belt happens to be the zone of 
convergence of trade winds from 
two hemispheres from sub-tropical high 
pressure belts.
• This belt is also called the Doldrums, 
because of the extremely calm air 
movements.
• The position of the belt varies with the 
apparent movement of the Sun.
Page 3


• There are distinctly identifiable zones of 
homogeneous horizontal pressure regimes 
or ‘pressure belts’. On the earth’s surface, there 
are in all seven pressure belts.
• The seven pressure belts are :
• equatorial low,
• the sub-tropical highs,
• the sub-polar lows, and
• the polar highs.
Equatorial Low Pressure Belt or ‘Doldrums’
• Lies between 10°N and 10°S 
latitudes.
• Width may vary between 5°N and 5°S 
and 20°N and 20°S.
• This belt happens to be the zone of 
convergence of trade winds from 
two hemispheres from sub-tropical high 
pressure belts.
• This belt is also called the Doldrums, 
because of the extremely calm air 
movements.
• The position of the belt varies with the 
apparent movement of the Sun.
Page 4


• There are distinctly identifiable zones of 
homogeneous horizontal pressure regimes 
or ‘pressure belts’. On the earth’s surface, there 
are in all seven pressure belts.
• The seven pressure belts are :
• equatorial low,
• the sub-tropical highs,
• the sub-polar lows, and
• the polar highs.
Equatorial Low Pressure Belt or ‘Doldrums’
• Lies between 10°N and 10°S 
latitudes.
• Width may vary between 5°N and 5°S 
and 20°N and 20°S.
• This belt happens to be the zone of 
convergence of trade winds from 
two hemispheres from sub-tropical high 
pressure belts.
• This belt is also called the Doldrums, 
because of the extremely calm air 
movements.
• The position of the belt varies with the 
apparent movement of the Sun.
Climate
• This belt is characterized by extremely low pressure with calm 
conditions.
• This is because of the absence of Surface winds since winds 
approaching this belt begin to rise near its margin. Thus, only 
vertical currents are found.
• As the larger part of the low pressure belt passes along the 
oceans, the winds obtain huge amount of moisture.
• Vertical winds (convection) carrying moisture 
form cumulonimbus clouds and lead to thunderstorms 
(convectional rainfall).
• Inspite of high temperatures, cyclones are not formed at 
the equator because of ‘zero’ coriolis force. (we will see more 
later)
Page 5


• There are distinctly identifiable zones of 
homogeneous horizontal pressure regimes 
or ‘pressure belts’. On the earth’s surface, there 
are in all seven pressure belts.
• The seven pressure belts are :
• equatorial low,
• the sub-tropical highs,
• the sub-polar lows, and
• the polar highs.
Equatorial Low Pressure Belt or ‘Doldrums’
• Lies between 10°N and 10°S 
latitudes.
• Width may vary between 5°N and 5°S 
and 20°N and 20°S.
• This belt happens to be the zone of 
convergence of trade winds from 
two hemispheres from sub-tropical high 
pressure belts.
• This belt is also called the Doldrums, 
because of the extremely calm air 
movements.
• The position of the belt varies with the 
apparent movement of the Sun.
Climate
• This belt is characterized by extremely low pressure with calm 
conditions.
• This is because of the absence of Surface winds since winds 
approaching this belt begin to rise near its margin. Thus, only 
vertical currents are found.
• As the larger part of the low pressure belt passes along the 
oceans, the winds obtain huge amount of moisture.
• Vertical winds (convection) carrying moisture 
form cumulonimbus clouds and lead to thunderstorms 
(convectional rainfall).
• Inspite of high temperatures, cyclones are not formed at 
the equator because of ‘zero’ coriolis force. (we will see more 
later)
Sub-Tropical High Pressure Belt or Horse Latitudes
• Formation
• After saturation (complete loss of moisture) at the ITCZ, the air moving 
away from equatorial low pressure belt in the upper troposphere 
becomes dry and cold.
• This dry and cold wind subsides at 30°N and S.
• So the high pressure along this belt is due to subsidence of air 
coming from the equatorial region which descends after becoming 
heavy.
• The high pressure is also due to the blocking effect of air at upper 
levels because of the Coriolis force.
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FAQs on PPT: Pressure Belts - Geography for UPSC CSE

1. What are pressure belts?
Ans. Pressure belts are large-scale atmospheric circulations that occur due to differences in air pressure at different latitudes. These belts are formed as a result of the unequal heating of the Earth's surface by the sun.
2. How many pressure belts are there on Earth?
Ans. There are three main pressure belts on Earth: the equatorial low-pressure belt (also known as the doldrums), the sub-tropical high-pressure belts (one in the Northern Hemisphere and one in the Southern Hemisphere), and the sub-polar low-pressure belts (also known as the polar fronts).
3. What causes the formation of pressure belts?
Ans. Pressure belts are primarily formed due to the uneven distribution of solar energy received by different parts of the Earth's surface. The equator receives more direct sunlight and thus gets heated more, creating a low-pressure area, while the poles receive less sunlight and remain relatively cooler, resulting in high-pressure areas.
4. How do pressure belts affect weather patterns?
Ans. Pressure belts play a crucial role in determining global weather patterns. The movement and interaction of these belts influence the formation of winds, the development of storms, and the distribution of rainfall. They also contribute to the formation of ocean currents and affect climate variability.
5. What is the significance of pressure belts in navigation?
Ans. Pressure belts have a significant impact on maritime navigation. Sailors and navigators often rely on the prevailing winds associated with these belts to plan their routes and determine the best sailing conditions. Understanding pressure belts helps in predicting weather patterns and avoiding regions of unfavorable winds and storms.
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