Question 1: If the surface air pressure is 1,000 mb, the air pressure at 1 km above the surface will be: (a) 700 mb (b) 1,100 mb (c) 900 mb (d) 1,300 mb
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(c) 900 mb — This is the textbook-supported choice for the question.
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CBSE Class 11GeographyQuestions & AnswersChapter level
Class 11 Geography: Atmospheric Circulation and Weather Systems — Chapter Question Set
Chapter-wise questions and answers for Class 11 Geography: Atmospheric Circulation and Weather Systems — Chapter Question Set in Class 11 Geography, with a clear summary, key points, and exam-ready model answers.
What you will find on this page: a clear chapter summary, revision notes, word meanings, important questions, MCQs, and exam-ready question answers for Class 11 Geography.
After reviewing the chapter explanation, answer the short-answer, long-answer, extract-based, and objective questions below.
About 35 min readChapter 9: Atmospheric Circulation and Weather SystemsUpdated 10 Sep 2026
Section A
1-Mark Questions
Objective questions · 1 mark each.
Question 2: The Inter Tropical Convergence Zone normally occurs: (a) near the Equator (b) near the Tropic of Cancer (c) near the Tropic of Capricorn (d) near the Arctic Circle
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(a) near the Equator — This is the textbook-supported choice for the question.
Question 3: The direction of wind around a low pressure in northern hemisphere is: (a) clockwise (b) perpendicular to isobars (c) anti-clock wise (d) parallel to isobars
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(c) anti-clock wise — This is the textbook-supported choice for the question.
Question 4: Which one of the following is the source region for the formation of air masses? (a) the Equatorial forest (b) the Himalayas (c) the Siberian Plain (d) the Deccan Plateau
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(c) the Siberian Plain — This is the textbook-supported choice for the question.
Question 5: ATMOSPHERIC CIRCULATION AND WEATHER _____ E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth. a) SYSTEMS b) that it causes the movement of air from high c) wind d) will rise or sink
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a) SYSTEMS — The textbook states: ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth.
Question 6: Air expands when heated and _____. a) wind b) will rise or sink c) planet as a whole d) gets compressed when cooled
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d) gets compressed when cooled — The textbook states: Air expands when heated and gets compressed when cooled.
Question 7: This results in variations _____. a) planet as a whole b) clouds and bring precipitation c) in the atmospheric pressure d) will rise or sink
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c) in the atmospheric pressure — The textbook states: This results in variations in the atmospheric pressure.
Question 8: The result is _____ pressure to low pressure, setting the air in motion. a) of violent tropical storms b) that it causes the movement of air from high c) planet as a whole d) clouds and bring precipitation
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b) that it causes the movement of air from high — The textbook states: The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion.
Question 9: You already know that air in horizontal motion is _____. a) wind b) clouds and bring precipitation c) of violent tropical storms d) subjected to a lot of air pressure
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a) wind — The textbook states: You already know that air in horizontal motion is wind.
Question 10: Atmospheric pressure also determines when the air _____. a) of violent tropical storms b) subjected to a lot of air pressure c) and one feels breathless d) will rise or sink
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d) will rise or sink — The textbook states: Atmospheric pressure also determines when the air will rise or sink.
Question 11: The wind redistributes the heat and moisture across the planet, thereby, maintaining a constant temperature for the _____. a) and one feels breathless b) called the atmospheric pressure c) planet as a whole d) subjected to a lot of air pressure
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c) planet as a whole — The textbook states: The wind redistributes the heat and moisture across the planet, thereby, maintaining a constant temperature for the planet as a whole.
Question 12: The vertical rising of moist air cools it down to form the _____. a) expressed in units of milibar b) clouds and bring precipitation c) and one feels breathless d) called the atmospheric pressure
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b) clouds and bring precipitation — The textbook states: The vertical rising of moist air cools it down to form the clouds and bring precipitation.
Question 13: This chapter has been devoted to explain the causes of pressure differences, the forces that control the atmospheric circulation, the turbulent pattern of wind, the formation of air masses, the disturbed weather when air masses interact with each other and the phenomenon _____. a) of violent tropical storms b) called the atmospheric pressure c) expressed in units of milibar d) 013.2
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a) of violent tropical storms — The textbook states: This chapter has been devoted to explain the causes of pressure differences, the forces that control the atmospheric circulation, the turbulent pattern of wind, the formation of air masses, the disturbed weather when air masses interact with each other and the phenomenon of violent tropical storms.
Question 14: ATMOSPHERIC PRESSURE Do you realise that our body is _____. a) expressed in units of milibar b) 013.2 c) denser and hence has higher pressure d) subjected to a lot of air pressure
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d) subjected to a lot of air pressure — The textbook states: ATMOSPHERIC PRESSURE Do you realise that our body is subjected to a lot of air pressure.
Question 15: As one moves up the air gets varified _____. a) denser and hence has higher pressure b) measured with the help of a mercury barometer c) and one feels breathless d) 013.2
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c) and one feels breathless — The textbook states: As one moves up the air gets varified and one feels breathless.
Question 16: The weight of a column of air contained in a unit area from the mean sea level to the top of the atmosphere is _____ . a) 2006 b) called the atmospheric pressure c) denser and hence has higher pressure d) measured with the help of a mercury barometer
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b) called the atmospheric pressure — The textbook states: The weight of a column of air contained in a unit area from the mean sea level to the top of the atmosphere is called the atmospheric pressure .
Question 17: The atmospheric pressure is _____. a) expressed in units of milibar b) measured with the help of a mercury barometer c) 2006 d) Practical
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a) expressed in units of milibar — The textbook states: The atmospheric pressure is expressed in units of milibar.
Question 18: At sea level the average atmospheric pressure is 1 ,_____ milibar. a) 2006 b) Practical c) Geography d) 013.2
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d) 013.2 — The textbook states: At sea level the average atmospheric pressure is 1 ,013.2 milibar.
Question 19: Due to gravity the air at the surface is _____. a) Geography b) Part c) denser and hence has higher pressure d) Practical
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c) denser and hence has higher pressure — The textbook states: Due to gravity the air at the surface is denser and hence has higher pressure.
Question 20: Air pressure is _____ or the aneroid barometer. a) NCERT b) measured with the help of a mercury barometer c) Geography d) Part
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b) measured with the help of a mercury barometer — The textbook states: Air pressure is measured with the help of a mercury barometer or the aneroid barometer.
Question 21: Consult your book, Practical W ork in Geography — Part I (NCERT, _____) and learn about these instruments. a) 2006 b) Part c) NCERT d) the primary cause of air motion
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a) 2006 — The textbook states: Consult your book, Practical W ork in Geography — Part I (NCERT, 2006) and learn about these instruments.
Question 22: At any elevation it varies from place to place and its variation is _____, i.e. a) NCERT b) to low pressure areas c) Pressure In d) the primary cause of air motion
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d) the primary cause of air motion — The textbook states: At any elevation it varies from place to place and its variation is the primary cause of air motion, i.e.
Question 23: wind which moves from high pressure areas _____. a) Pressure In b) 10 m c) to low pressure areas d) the primary cause of air motion
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c) to low pressure areas — The textbook states: wind which moves from high pressure areas to low pressure areas.
Question 24: Vertical Variation of _____ the lower atmosphere the pressure decreases rapidly with height. a) at the same rate b) Pressure In c) to low pressure areas d) 10 m
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b) Pressure In — The textbook states: Vertical Variation of Pressure In the lower atmosphere the pressure decreases rapidly with height.
Question 25: The decrease amounts to about 1 mb for each _____ increase in elevation. a) 10 m b) Pressure In c) at the same rate d) 10 km
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a) 10 m — The textbook states: The decrease amounts to about 1 mb for each 10 m increase in elevation.
Question 26: It does not always decrease _____. a) 10 m b) 10 km c) 265.00 d) at the same rate
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d) at the same rate — The textbook states: It does not always decrease at the same rate.
Question 27: 3 _____ 265.00 – 49.7 The vertical pressure gradient force is much larger than that of the horizontal pressure gradient. a) 265.00 b) 49.7 c) 10 km d) at the same rate
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c) 10 km — The textbook states: 3 10 km 265.00 – 49.7 The vertical pressure gradient force is much larger than that of the horizontal pressure gradient.
Question 28: But, it is _____site gravitational force. a) 49.7 b) generally balanced by a nearly equal but oppo c) 10 km d) 265.00
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b) generally balanced by a nearly equal but oppo — The textbook states: But, it is generally balanced by a nearly equal but opposite gravitational force.
Question 29: CHAPTER ATMOSPHERIC CIRCULATION AND _____ 77 Horizontal Distribution of Pressure Small differences in pressure are highly significant in terms of the wind direction and purposes of comparison. a) WEATHER SYSTEMS b) 265.00 c) 49.7 d) much larger than that of the horizontal press
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a) WEATHER SYSTEMS — The textbook states: CHAPTER ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS 77 Horizontal Distribution of Pressure Small differences in pressure are highly significant in terms of the wind direction and purposes of comparison.
Question 30: The sea level pressure distribution is _____. a) 49.7 b) much larger than that of the horizontal press c) generally balanced by a nearly equal but oppo d) shown on weather maps
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d) shown on weather maps — The textbook states: The sea level pressure distribution is shown on weather maps.
Question 31: Lowpressure system is _____st pressure in the centre. a) generally balanced by a nearly equal but oppo b) experience strong upward winds c) enclosed by one or more isobars with the lowe d) much larger than that of the horizontal press
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c) enclosed by one or more isobars with the lowe — The textbook states: Lowpressure system is enclosed by one or more isobars with the lowest pressure in the centre.
Question 32: High-pressure system is _____ highest pressure in the centre. a) WEATHER SYSTEMS b) also enclosed by one or more isobars with the c) generally balanced by a nearly equal but oppo d) experience strong upward winds
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b) also enclosed by one or more isobars with the — The textbook states: High-pressure system is also enclosed by one or more isobars with the highest pressure in the centre.
Question 33: Near the equator the sea level pressure is _____ . a) low and the area is known as equatorial low b) experience strong upward winds c) WEATHER SYSTEMS d) Horizontal Distribution
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a) low and the area is known as equatorial low — The textbook states: Near the equator the sea level pressure is low and the area is known as equatorial low .
Question 34: Along 30° N and 30 o S are _____btropical highs. a) WEATHER SYSTEMS b) Horizontal Distribution c) Pressure Small d) found the high-pressure areas known as the su
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d) found the high-pressure areas known as the su — The textbook states: Along 30° N and 30 o S are found the high-pressure areas known as the subtropical highs.
Question 35: Further pole wards along 60o N and 60 o S, the low-pressure belts are _____. a) Pressure Small b) highly significant in terms of the wind direc c) termed as the sub polar lows d) Horizontal Distribution
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c) termed as the sub polar lows — The textbook states: Further pole wards along 60o N and 60 o S, the low-pressure belts are termed as the sub polar lows.
Question 36: Near the poles the pressure is _____. a) shown on weather maps b) high and it is known as the polar high c) Pressure Small d) highly significant in terms of the wind direc
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b) high and it is known as the polar high — The textbook states: Near the poles the pressure is high and it is known as the polar high.
Question 37: Horizontal distribution of pressure is _____. a) studied by drawing isobars at constant levels b) highly significant in terms of the wind direc c) shown on weather maps d) enclosed by one or more isobars with the lowe
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a) studied by drawing isobars at constant levels — The textbook states: Horizontal distribution of pressure is studied by drawing isobars at constant levels.
Question 38: In order to eliminate the effect of altitude on pressure, it is measured at any station after being reduced to sea level for _____ differences in atmospheric pressure produces a force. a) shown on weather maps b) enclosed by one or more isobars with the lowe c) also enclosed by one or more isobars with the d) Pressure Gradient Force The
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d) Pressure Gradient Force The — The textbook states: In order to eliminate the effect of altitude on pressure, it is measured at any station after being reduced to sea level for Pressure Gradient Force The differences in atmospheric pressure produces a force.
Question 39: The rate of change of pressure with respect to distance is _____. a) also enclosed by one or more isobars with the b) low and the area is known as equatorial low c) the pressure gradient d) enclosed by one or more isobars with the lowe
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c) the pressure gradient — The textbook states: The rate of change of pressure with respect to distance is the pressure gradient.
Question 40: The pressure gradient is _____her and is weak where the isobars are apart. a) found the high-pressure areas known as the su b) strong where the isobars are close to each ot c) also enclosed by one or more isobars with the d) low and the area is known as equatorial low
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b) strong where the isobars are close to each ot — The textbook states: The pressure gradient is strong where the isobars are close to each other and is weak where the isobars are apart.
Question 41: Frictional Force It affects the _____. a) speed of the wind b) low and the area is known as equatorial low c) found the high-pressure areas known as the su d) termed as the sub polar lows
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a) speed of the wind — The textbook states: Frictional Force It affects the speed of the wind.
Question 42: It is greatest at the surface and its influence generally extends upto an elevation of 1 - _____. a) found the high-pressure areas known as the su b) termed as the sub polar lows c) high and it is known as the polar high d) 3 km
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d) 3 km — The textbook states: It is greatest at the surface and its influence generally extends upto an elevation of 1 - 3 km.
Question 43: Over the sea surface the friction is _____. a) high and it is known as the polar high b) studied by drawing isobars at constant levels c) minimal d) termed as the sub polar lows
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c) minimal — The textbook states: Over the sea surface the friction is minimal.
Question 44: Coriolis Force The rotation of the earth about its axis affects the _____. a) lines connecting places having equal pressure b) direction of the wind c) high and it is known as the polar high d) studied by drawing isobars at constant levels
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b) direction of the wind — The textbook states: Coriolis Force The rotation of the earth about its axis affects the direction of the wind.
Question 45: This force is called the Coriolis force after the French physicist who described it in _____. a) 1844 b) studied by drawing isobars at constant levels c) lines connecting places having equal pressure d) Pressure Gradient Force The
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a) 1844 — The textbook states: This force is called the Coriolis force after the French physicist who described it in 1844.
Question 46: It deflects the wind to the right direction in the northern _____. a) lines connecting places having equal pressure b) Pressure Gradient Force The c) measured at any station after being reduced t d) hemisphere and in nature
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d) hemisphere and in nature — The textbook states: It deflects the wind to the right direction in the northern hemisphere and in nature.
Question 47: They oscillate with the apparent _____. a) measured at any station after being reduced t b) the pressure gradient c) movement of the sun d) Pressure Gradient Force The
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c) movement of the sun — The textbook states: They oscillate with the apparent movement of the sun.
Question 48: In the northern hemisphere in winter they move southwards and _____. a) strong where the isobars are close to each ot b) in the summer northwards c) measured at any station after being reduced t d) the pressure gradient
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b) in the summer northwards — The textbook states: In the northern hemisphere in winter they move southwards and in the summer northwards.
Question 49: Forces Affecting the _____ and Direction of Wind You already know that the air is set in motion due to the differences in atmospheric pressure. a) Velocity b) the pressure gradient c) strong where the isobars are close to each ot d) weak where the isobars are apart
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a) Velocity — The textbook states: Forces Affecting the Velocity and Direction of Wind You already know that the air is set in motion due to the differences in atmospheric pressure.
Question 50: The wind blows from high _____. a) strong where the isobars are close to each ot b) weak where the isobars are apart c) speed of the wind d) pressure to low pressure
Show answer
d) pressure to low pressure — The textbook states: The wind blows from high pressure to low pressure.
Section B2
2-Mark Questions
Short-answer questions · 2 marks each.
Question 51: What is the unit used in measuring pressure? Why is the pressure measured at station level reduced to the sea level in preparation of weather maps?
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The weight of a column of air contained in a unit area from the mean sea level to the top of the atmosphere is called the atmospheric pressure . The sea level pressure distribution is shown on weather maps. In order to eliminate the effect of altitude on pressure, it is measured at any station after being reduced to sea level for Pressure Gradient Force The differences in atmospheric pressure produces a force.
Question 52: While the pressure gradient force is from north to south, i.e. from the subtropical high pressure to the equator in the northern hemisphere, why are the winds north easterlies in the tropics.
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Thus, the horizontal winds near the earth surface respond to the combined effect of three forces – the pressure gradient force, the frictional force and the Coriolis force. The winds in the upper atmosphere, 2 - 3 km above the surface, are free from frictional effect of the surface and are controlled mainly by the pressure gradient and the Coriolis force. In the northern hemisphere, warm air blows from the south and cold air from the north of the front.
Question 53: What are the geotrophic winds?
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Hence, we do not experience strong upward winds. Thus, the horizontal winds near the earth surface respond to the combined effect of three forces – the pressure gradient force, the frictional force and the Coriolis force. The winds in the upper atmosphere, 2 - 3 km above the surface, are free from frictional effect of the surface and are controlled mainly by the pressure gradient and the Coriolis force.
Question 54: Explain the land and sea breezes. Thunderstorms and Tornadoes Other severe local storms are thunderstorms and tornadoes. They are of short duration, occurring over a small area but are violent. Thunderstor ms are caused by intense convection on moist hot days. A thunderstorm is a well-grown cumulonimbus cloud producing thunder and lightening. When the clouds extend to heights where sub-zero temperature prevails, hails are formed and they come down as hailstorm. If there is insufficient moisture, a thunderstorm can generate duststorms. A thunderstorm is characterised by intense updraft of rising war m air , which causes the clouds to grow bigger and rise to greater height. This causes precipitation. Later, downdraft brings down to earth the cool air and the rain. From severe thunderstorms sometimes spiralling wind descends like a trunk of an elephant with great force, with very low pressure at the centre, causing massive destruction on its way. Such a phenomenon is called a tornado. Tornadoes generally occur in middle latitudes. The tornado over the sea is called water spouts. These violent storms are the manifestation of the atmosphere’s adjustments to varying energy distribution. The potential and heat energies are converted into kinetic energy in these storms and the restless atmosphere again returns to its stable state. Reprint 2026-27 ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS 85
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This chapter has been devoted to explain the causes of pressure differences, the forces that control the atmospheric circulation, the turbulent pattern of wind, the formation of air masses, the disturbed weather when air masses interact with each other and the phenomenon of violent tropical storms. CHAPTER ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS 77 Horizontal Distribution of Pressure Small differences in pressure are highly significant in terms of the wind direction and purposes of comparison. The conditions favourable for the formation and intensification of tropical storms are: (i) Large sea surface with temperature higher than 27° C; (ii) Presence of the Coriolis force; (iii) Small variations in the vertical wind speed; (iv) A pre-existing weaklow-pressure area or low-level-cyclonic circulation; (v) Upper divergence above the sea level system.
Question 55: What does the textbook explain about ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 describ?
Show answer
ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth.
Question 56: What does the textbook explain about Air expands when heated and gets compressed when cooled?
Show answer
Air expands when heated and gets compressed when cooled.
Question 57: What does the textbook explain about This results in variations in the atmospheric pressure?
Show answer
This results in variations in the atmospheric pressure.
Question 58: What does the textbook explain about The result is that it causes the movement of air from high pressure to?
Show answer
The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion.
Question 59: What does the textbook explain about You already know that air in horizontal motion is wind?
Show answer
You already know that air in horizontal motion is wind.
Question 60: What does the textbook explain about Atmospheric pressure also determines when the air will rise or sink?
Show answer
Atmospheric pressure also determines when the air will rise or sink.
Question 61: What does the textbook explain about The wind redistributes the heat and moisture across the planet, thereb?
Show answer
The wind redistributes the heat and moisture across the planet, thereby, maintaining a constant temperature for the planet as a whole.
Question 62: What does the textbook explain about The vertical rising of moist air cools it down to form the clouds and?
Show answer
The vertical rising of moist air cools it down to form the clouds and bring precipitation.
Question 63: What does the textbook explain about This chapter has been devoted to explain the causes of pressure differ?
Show answer
This chapter has been devoted to explain the causes of pressure differences, the forces that control the atmospheric circulation, the turbulent pattern of wind, the formation of air masses, the disturbed weather when air masses interact with each other and the phenomenon of violent tropical storms.
Question 64: What does the textbook explain about ATMOSPHERIC PRESSURE Do you realise that our body is subjected to a lo?
Show answer
ATMOSPHERIC PRESSURE Do you realise that our body is subjected to a lot of air pressure.
Question 65: What does the textbook explain about As one moves up the air gets varified and one feels breathless?
Show answer
As one moves up the air gets varified and one feels breathless.
Section B3
3-Mark Questions
Short-answer questions · 3 marks each.
Question 66: What does the textbook explain about The weight of a column of air contained in a unit area from the mean s?
Show answer
The weight of a column of air contained in a unit area from the mean sea level to the top of the atmosphere is called the atmospheric pressure .
Question 67: What does the textbook explain about The atmospheric pressure is expressed in units of milibar?
Show answer
The atmospheric pressure is expressed in units of milibar.
Question 68: What does the textbook explain about At sea level the average atmospheric pressure is 1 ,013.2 milibar?
Show answer
At sea level the average atmospheric pressure is 1 ,013.2 milibar.
Question 69: What does the textbook explain about Due to gravity the air at the surface is denser and hence has higher p?
Show answer
Due to gravity the air at the surface is denser and hence has higher pressure.
Question 70: What does the textbook explain about Air pressure is measured with the help of a mercury barometer or the a?
Show answer
Air pressure is measured with the help of a mercury barometer or the aneroid barometer.
Question 71: What does the textbook explain about Consult your book, Practical W ork in Geography — Part I (NCERT, 2006)?
Show answer
Consult your book, Practical W ork in Geography — Part I (NCERT, 2006) and learn about these instruments.
Question 72: What does the textbook explain about At any elevation it varies from place to place and its variation is th?
Show answer
At any elevation it varies from place to place and its variation is the primary cause of air motion, i.e.
Question 73: What does the textbook explain about wind which moves from high pressure areas to low pressure areas?
Show answer
wind which moves from high pressure areas to low pressure areas.
Question 74: What does the textbook explain about Vertical Variation of Pressure In the lower atmosphere the pressure de?
Show answer
Vertical Variation of Pressure In the lower atmosphere the pressure decreases rapidly with height.
Question 75: What does the textbook explain about The decrease amounts to about 1 mb for each 10 m increase in elevation?
Show answer
The decrease amounts to about 1 mb for each 10 m increase in elevation.
Section C
5-Mark Questions
Broad-answer questions · 5 marks each.
Question 76: Discuss the factors affecting the speed and direction of wind.
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CHAPTER ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS 77 Horizontal Distribution of Pressure Small differences in pressure are highly significant in terms of the wind direction and purposes of comparison. Frictional Force It affects the speed of the wind. Coriolis Force The rotation of the earth about its axis affects the direction of the wind. It deflects the wind to the right direction in the northern hemisphere and in nature. Forces Affecting the Velocity and Direction of Wind You already know that the air is set in motion due to the differences in atmospheric pressure. The higher the pressure gradient force, the more is the velocity of the wind and the larger is the deflection in the direction of wind. Pressure and Wind The velocity and direction of the wind are the net result of the wind generating forces.
Question 77: Draw a simplified diagram to show the general circulation of the atmosphere over the globe. What are the possible reasons for the formation of subtropical high pressure over 30 o N and S latitudes?
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This chapter has been devoted to explain the causes of pressure differences, the forces that control the atmospheric circulation, the turbulent pattern of wind, the formation of air masses, the disturbed weather when air masses interact with each other and the phenomenon of violent tropical storms. Along 30° N and 30 o S are found the high-pressure areas known as the subtropical highs. The pattern of the movement of the planetary winds is called the general circulation of the atmosphere. The general circulation of the atmosphere also affects the oceans. 6 : Simplified general circulation of the atmosphere The air at the Inter Tropical Convergence Zone (ITCZ) rises because of convection caused by high insolation and a low pressure is created. In the middle latitudes the circulation is that of sinking cold air that comes from the poles and the rising warm air that blows from the subtropical high. These three cells set the pattern for the general circulation of the atmosphere.
Question 78: Why does tropical cyclone originate over the seas? In which part of the tropical cyclone do torrential rains and high velocity winds blow and why?
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The deflection is more when the wind velocity is high. 6 : Simplified general circulation of the atmosphere The air at the Inter Tropical Convergence Zone (ITCZ) rises because of convection caused by high insolation and a low pressure is created. Part of the accumulated air sinks to the ground and forms a subtropical high. Extra Tropical Cyclones The systems developing in the mid and high latitude, beyond the tropics are called the middle latitude or extra tropical cyclones. Whereas the tropical cyclones originate only over the seas and on reaching the land they dissipate. The wind velocity in a tropical cyclone is much higher and it is more destructive. Tropical Cyclones T ropical cyclones ar e violent stor ms that originate over oceans in tropical areas and move over to the coastal areas bringing about large scale destruction caused by violent winds, very heavy rainfall and storm surges.
Question 79: Explain the textbook discussion of ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 describ and its geographical significance.
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ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth. ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth. Air expands when heated and gets compressed when cooled. This results in variations in the atmospheric pressure.
Question 80: Explain the textbook discussion of Air expands when heated and gets compressed when cooled and its geographical significance.
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Air expands when heated and gets compressed when cooled. ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS E arlier Chapter 8 described the uneven distribution of temperature over the surface of the earth. Air expands when heated and gets compressed when cooled. This results in variations in the atmospheric pressure. The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion.
Question 81: Explain the textbook discussion of This results in variations in the atmospheric pressure and its geographical significance.
Show answer
This results in variations in the atmospheric pressure. Air expands when heated and gets compressed when cooled. This results in variations in the atmospheric pressure. The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion. You already know that air in horizontal motion is wind.
Question 82: Explain the textbook discussion of The result is that it causes the movement of air from high pressure to and its geographical significance.
Show answer
The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion. This results in variations in the atmospheric pressure. The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion. You already know that air in horizontal motion is wind. Atmospheric pressure also determines when the air will rise or sink.