KBPE Class 10 Social Science II Textbook Part 1 PDF

Standard X Part - 1 NT-483-1-SOC.SCI.-II-10-E-VOL.1 Government of Kerala...

Standard X Part - 1 NT-483-1-SOC.SCI.-II-10-E-VOL.1 Government of Kerala Department of Education State Council of Educational Research and Training (SCERT, Kerala) 2019  THE NATIONAL ANTHEM Jana-gana-mana-adhinayaka, jaya he Bharata-bhagya-vidhata. Punjab-Sindh-Gujarat-Maratha Dravida-Utkala-Banga Vindhya-Himachala-Yamuna-Ganga Uchchala-Jaladhi-taranga. Tava shubha name jage, Tava shubha asisa mage, Gahe tava jaya gatha, Jana-gana-mangala-dayaka jaya he Bharata-bhagya-vidhata. Jaya he, jaya he, jaya he, Jaya jaya jaya, jaya he! PLEDGE India is my country. All Indians are my brothers and sisters. I love my country, and I am proud of its rich and varied heritage. I shall always strive to be worthy of it. I shall give my parents, teachers and all elders re- spect, and treat everyone with courtesy. To my country and my people, I pledge my devo- tion. In their well-being and prosperity alone lies my happiness. Dear Students, You have already learnt how diverse and dynamic the earth we live in. We can make use of the diversities of nature for the progress of mankind with the help of technology. The lessons in Class X are so arranged as to help familiarize the physiography, climate, and soil of our country, and to develop a general awareness on the use of the potentials of modern technology in geography. We are living in a world where human resource development is necessary. This textbook also discusses concepts like the society in which we regularly interact, the economic transactions in the society, banks and their functions, and national income. The educational portal-Samagra and textbooks with QR code will make class room activities easy and interesting. The Textbook has been revised considering the National Skill Qualifications Frame work (NSQF), the disaster mitigation measures which is of contemporary relevance and ICT possibilities. You can take part in this life oriented informative and joyful learning activities and enrich this textbook further more. I believe that this textbook will help you intereact responsibly with the nature and that you can transform into responsible citizens. With love and regards Dr. J. Prasad Director, SCERT State Council of Educational Research and Training (SCERT) Poojappura, Thiruvananthapuram 695 012, Kerala Website : www.scertkerala.gov.in, e-mail : [email protected] Phone : 0471 - 2341883, Fax : 0471 - 2341869 Typesetting and Layout : SCERT Printed at : KBPS, Kakkanad, Kochi-30 © Department of Education, Government of Kerala 01. Seasons and Time............................................................... 07 02. In search of the source of wind....................................... 21 03. Human Resource Development in India....................... 37 04. Landscape analysis through maps.................................. 51 05. Public Expenditure and Public Revenue....................... 75 Certain icons are used in this textbook for convenience For further reading (Need not be subjected to assessment) Questions for assessing the progress Learning activities Let us assess Extended activities  Standard X The wonders of seasonal change exhibited by the nature are varied. Winter is the season where everything is buried in snow. As the winter retreats, the grass and trees slowly turn green. The spring season arrives with leaves and flowers in different hues. Then summer sets in, bidding adieu to the reign of spring. Comes the long rainy season as a relief to the scorching summer and then follows the autumn. Trees start shedding their leaves within a few weeks in preparation to welcome the forthcoming winter. And the winter returns. Months of severe cold then. Such astonishing visuals that the nature prepares are more pronounced in the Mid Latitudes. While it is noon at one place it is midnight elsewhere. Two different days but at the same time on the earth! Just like the wonders of the seasons, the sequence of time is also diverse. You have just read a brief note on the seasonal changes. We experience the recurrence of winter, summer and rainy seasons one after the other. Such a change on the Earth is known as seasonal change. 7 Seasons and Time Social Science II Why seasons change? You have learnt that there is periodic variation in the amount of sunshine over different places in both the hemispheres of the Earth. Why does this happen? Variations in the amount of sunshine are the important special feature of the different seasons. The Earth's revolution and the tilt of the axis are the reasons for this variation. You know that it is in an elliptical orbit that the Earth revolves around the Sun. This is known as revolution. How much time does the Earth take to complete one revolution? What is a leap year? You have learnt in the previous classes that the axis of the Earth is tilted at an angle of 66½° from the orbital plane. If measured from the vertical plane this would be 23½° (Fig.1.1). The Earth maintains this tilt throughout its revolution (Fig 1.2). This is known as the parallelism of the Earth's axis. 23½° North Pole e C ircl tic Arc 66½° cer Sun rays of Can Night pic Tro Orbital Plane ator Equ orn Ca pric of Day pic Tro le tic Circ arc Ant South Pole Fig 1.1 Sun and Earth: near and far The distance between the Earth and the Sun will vary continuously throughout the period of one revolution. The days on which the Sun and the Earth are nearest and farthest Perihelion Aphelion are shown in the diagram. These days are known as Perihelion and Aphelion respec- 147 Million Km 152 Million Km tively. January 3 July 4 8 Seasons and Time  Standard X September December June March Fig 1.2 Observe the parallelism of the Earth's axis from the diagram (Fig.1.2). Since the parallelism is maintained same throughout the revolution, the position of the Sun in relation to the Earth varies apparently between Tropic of Cancer (23½° North) and Tropic of Capricorn (23½° South). This is known as the apparent movement of the Sun. The apparent movement of the Sun, due to the inclination of axis, is the reason for the occurrence of seasons. Look at Fig. 1.2. Four different positions of the Earth during a single revolution (one year) around the Sun are depicted in it. There is variation in the sunlight that falls on the Earth due to the apparent movement of the Sun. The Sun's rays fall vertically over one hemisphere during one half of the year and on the other hemisphere, during the other half. Temperature will be higher over those places where the vertical rays of the Sun fall. The temperature will be low at places where the Sun's rays are slanting. Seasons and apparent movement of the Sun As a result of the apparent movement of the sun between Tropic of Cancer (23½°N) and Tropic of Capricorn (23½°S), the different seasons - Spring, Summer, Autumn and Winter - get repeated in a cyclic manner. Seasonal changes are not usually very obvious in the tropical regions because of the incidence of large amount of Sun's rays throughout the year. 9 Seasons and Time Social Science II Seasons are not distinctly felt in Kerala. Why? Characteristics of different seasons are clearly felt in the mid latitudinal or temperate zones. The frigid zones do not experience all the seasons. Discuss the reason. Equal amount of sunlight is received in the Northern Hemisphere as well as in the Southern Hemisphere when the Sun is vertically over the Equator. The apparent position of the Sun during the Earth's revolution will be over the Equator on March 21 and September 23. Hence the length of day and night will Fig 1.3 be equal during these days on both the hemispheres (Fig.1.3). These days are called equinoxes. From 21 March onwards, the Sun apparently shifts from the Equator northwards and reaches vertically over the Tropic of Cancer (23½°N) on 21 June. This day is known as the Summer Solstice in the Northern Hemisphere. On this day the Northern Hemisphere experiences its longest day and shortest night. What is the peculiarity of the day and the night in the Southern Hemisphere on 21 June? The Northern Hemisphere generally experiences spring season between 21 March and 21 June. Spring is the season of transition from winter to summer. Haven't you noticed the plants sprouting, mango trees blooming and jackfruit trees bearing buds and the like? These are the peculiarities of spring season. Read Table 1.1 and identify the season in the Fig 1.4 Southern Hemisphere during this period. 10 Seasons and Time  Standard X The southward apparent movement of the Sun begins from 21 June and again reaches vertically above the Equator on 23 September. Summer season is experienced in the Northern Hemisphere during this period. What are the changes observed in nature during the summer season? The Sun continues its southward apparent shift Fig 1.5 from the Equator from 23 September and reaches vertically above Tropic of Capricorn (23½°S) on 22 December. This day is known as Winter Solstice in the Northern Hemisphere. On this day the Northern Hemisphere experiences its shortest day and longest night. What is the peculiarity of the day and the night in the Southern Hemisphere on 22 December? It is autumn season in the Northern Hemisphere from 23 September to 22 December. Autumn marks the transition from the severity of summer towards winter. During this period, the atmospheric temperature decreases considerably. There is shortening of day and lengthening of night during the period. This is the season during which the trees generally shed their leaves. The shedding of leaves is a form of adaptation to survive the forthcoming dry winter. What is the season in the Southern Hemisphere, when it is autumn in the Northern Hemisphere? (see Table 1.1) Fig 1.6 The northward apparent shift of the Sun begins by 22 December and again reaches vertically above the Equator on 21 March. This period marks the winter season in the Northern Hemisphere. What are the peculiarities of winter season? Which will be the season in the Southern Hemisphere when it is winter in the Northern Hemisphere? Observe Table 1.1 and find out. Fig 1.7 11 Seasons and Time Social Science II The apparent Seasons Months movement of the sun Northern Southern hemisphere hemisphere From March 21 to From the Equator to Tropic Spring Autumn June 21 of Cancer From June 21 to From Tropic of Cancer Summer Winter September 23 to the Equator From September 23 From the Equator to Autumn Spring to December 22 Tropic of Capricon From December 22 From Tropic of Capricon Winter Summer to March 21 to the Equator Table 1.1 Traditional seasons Utharayanam and Dakshinayanam of India You might have understood the apparent Though the Indian seasons are generally classified into four, it movement of the Sun and the resultant seasons is estimated that there are six in both the hemispheres. Following the winter seasons in India based on the solstice, the Sun sets its northward apparent changes in the atmospheric con- movement from Tropic of Capricorn (23½°S) and ditions. it culminates on Tropic of Cancer (23½°N) on 21 Vasantha- March, April June. This northward apparent movement of the Greeshma- May, June Sun from Tropic of Capricorn to Tropic of Cancer Varsha- July - August is termed as 'Utharayanam'. The duration of day Sarat - September, October in the northern hemisphere gradually increases Hemanta - November, during this period. December Following the summer solstice, the Sun sets its Sisira- January, February southward apparent movement from Tropic of Cancer (23½°N) and it culminates on Tropic of Capricorn (23½°S) on 22 December. This southward apparent movement of the Sun from Tropic of Cancer to Tropic of Capricorn is termed as 'Dakshinayanam'. What is the change that occurs in the duration of day in the Southern Hemisphere during 'Dakshinayanam'? During the period from March to September, as the Sun is in the Northern Hemisphere, the north polar regions experience continuous daylight for six months. 12 Seasons and Time  Standard X During the remaining period, that is from September to March, as the Sun is in the Southern Hemisphere north polar regions experience continuous night for six months. What is the duration of day and night in the south polar regions, when the Sun is respectively over the Northern Hemisphere and Southern Hemisphere? Rotation and calculation of time I looked at the clock - it was showing 12. The air hostess announced that we should set all our watches back by five and a half hours. As per our watches it was 5. 30 Indian Standard Time. One could say the aircraft was flying towards the West, literally swallowing our Indian Standard Time! We had to turn back the hands of our watches every now and then accordingly. Translated from S K Pottekkat's Pathirasooryante Naattil ("In the Land of the Midnight Sun") Hope you read the extract from "Pathira The midnight sun sooryante Naattil", the famous travelogue The Sun shines even at midnight! Not for a by the renowned author S.K. Pottekkatt. single day, but for six months throughout, in Aren't you now convinced that time in the Arctic and the Antarctic Circles. But don't other countries is different from the time think that the Sun will be vertically overhead in India. Let’s examine the reason behind during those days. The Sun can be seen only this difference. on the horizon. The remaining six months are shrouded in darkness. Daylight lasts only In the ancient period, time was calculated for one or two hours. The land will be cov- NT-483-2-SOC.SCI.-II-10-E-VOL.1 based on the apex position of the Sun and ered with snow. Human life and limited ag- the length of the shadow cast by it. When riculture here are all scheduled according to the Sun is vertically overhead, it is noon. the peculiarities of this climate. Thus the time estimated at each place, based on the position of the Sun, is termed as the local time. Is the local time in all the Indian states the same? 13 Seasons and Time Social Science II What will be the hardships if there are several local times in a country? Cannot prepare a railway time table applicable throughout the country. Cannot give announcements about radio programs. Later on, the calculation of time became more scientific and accurate. Let’s go into the details of time calculation. You know that the earth rotates on its axis while it revolves. You have also learnt that day and night occur due to rotation. Look at some of the facts associated with rotation. The Earth rotates from west to east (Fig.1.10). It takes 24 hours to complete one rotation. As the Earth rotates from west to east, the Sun rises in the east. Fig 1.8 The people of which Indian State can see the Sun rise first? The angular distance of the Earth is 360°. We will get 360 longitudes if we draw one longitude each for each degree of angular distance. The time required to complete a 360° rotation is 24 hours. On converting 24 hours into minutes 24  60 = 1440 minutes That is, the time required for the completion of one rotation = 1440 minutes The time required for the Earth to complete the rotation of 1° longitude is 1440 = 4 minutes. 360 14 Seasons and Time  Standard X  The time required for the rotation of 15° longitudinal area 12 is 11.56 am Noon 12.4 pm 15  4 = 60 minutes (1 hour). In otherwords, 15° longitudinal area of the Earth passes by the Sun within a period of one hour. As the Earth rotates from west to east, time advances towards the east and recedes towards the west. Look at the illustration. 1° 0° 1° From a definite longitude, the time is estimated to increase East West by 4 minutes towards the east and decrease by 4 minutes towards the west for every degree of longitude. Greenwich time (GMT) and time zones The zero degree longitude is known as the Greenwich Meridian. It acquires its name from Greenwich, the place where the Royal British Observatory is situated (Fig.1.9) and through which this line passes. Time is calculated worldwide based on the Greenwich Line. Hence this line is also known as the prime meridian. The local time at the prime meridian is known as the Greenwich Mean Time. Based on the Greenwich Merdian, the world is divided into 24 zones, each with a time difference of one hour. These are known as time zones. What would be the longitudinal extent of each time zone? Standard time Fig1.9 The local time would be different at each longitude. If we start calculating the local time at different places based on the longitude there, it would create a lot of confusion. To solve this, the local time at the longitude that passes through the middle of a country is selected as the common time for the whole country. Each country in the world considers the longitude that passes almost through its middle as the standard meridian. The countries with large longitudinal extent estimates more than one local time by considering more than one standard meridian. The local time at the standard meridian is the standard time of that country. 15 Seasons and Time Social Science II Indian Standard Time (IST) The longitudinal extent of India is from 68°E to 97°E. The 82½°E longitude which passes almost through the middle of these longitudes has been fixed as the standard meridian of India. The local time along this longitude is generally considered as the Standard Time of India. This is known as the Indian Standard Time. Find the difference between the Indian Standard Time and the Greenwich Mean Time. International Date Line Calculate the time at each 15° longitude east and west of the Greenwich Line up to 180° longitude and complete the table. Time at Greenwich - Friday 10 A.M. To the west of Greenwich To the east of Greenwich Longitude Day Time Longitude Day Time 150 Friday 9 am 150 Friday 11 am 300 Friday 8 am 300 Friday 12 noon 450 450 600 600 750 750 900 900 1050 1050 1200 1200 1350 1350 1500 1500 1650 1650 1800 1800 Table 1.2 16 Seasons and Time  Standard X You might have noticed that there is a diffence of 24 hours, at 180° longitude to the east and west of Greenwich. The place ‘A’ marked in the given figure (Fig. 1.10) is located at 180° longitude. Which day would it be for those residing at place ‘A’ in Fig. 1.10? If 180° longitude passes through a country, the Fig 1.10 places situated East and West of this line will be having two different days. Think about the practical difficulties caused by this. To avoid this, certain necessary adjustments have been effected in this line with the result that it doesn’t pass through the corresponding land areas. Note the longitude marked with broken lines. The line is in such a way that it passes through Bering - strait in Pacific Ocean and avoid some of the inhabited islands. The travellers who cross this line from the West calculate the time by advancing it by one day and those who cross the line from the west deduct one day. This imaginary line is known as the International Date Line. Note the International Date Line marked on the globe. Identify the continents situated to the east and the west of this line. The travellers to which of these continents will gain one day on crossing the International Date Line? Let’s calculate time 0° 82°30E Example 1 What will be the time in India when it is 12 noon at Greenwich? Let us see how the time of India is calculated: The longitudinal difference between India and Greenwich = 82°30 Greenwich India 17 Seasons and Time Social Science II The time difference for 15° longitude = 1 hour The time difference for 82°30 longitude = = 5½ hours = 5 hours 30 minutes As India is located to the east of Greenwich, the time in India will be 5 hours and 30 minutes ahead of Greenwich Mean Time. Therefore the time at India = Time at Greenwich  Time difference = 12 Noon + 5 hours 30 minutes = 5.30 pm Example 2. What will be the time in Japan (135° East) when it is 11 pm on Monday in India? 82°30 135° East India Japan The longitudinal difference between India and Japan = 135° - 82°30 = 52°30  Time difference for 1° longitude is 4 minutes. Time difference for 52°30 longitude = 52½  4 = 210 minutes = 3 hours 30 minutes 18 Seasons and Time  Standard X As Japan is situated at the east of India, the time in Japan would be 3 hours and 30 minutes ahead of that time in India. When it is 11 pm on Monday in India, the time in Japan = 11 pm Monday + 3 hours 30 minutes = 2.30 am Tuesday Let us assess Identify the factor not responsible for the occurrence of seasons. a. Revolution of the Earth b. Tilt of the earth's axis c. Parallelism of the Earth's axis d. Rotation of the Earth The Sun's rays fall vertically between Tropic of Cancer and Tropic of Capricon. Why? Explain the geographical importance of March 21, June 21, September 23, and December 22. Why is there an eastward increase and westward decrease in time? Extended activities In the class, exhibit pictures along with short notes depiciting the seasonal changes in nature. Record your observations on the changes in nature in each season and prepare a weather observation diary. With the help of an atlas, find out the standard meridians of different countries and calculate their local time. 19 Seasons and Time Social Science II 8 July 1497 Vasco da Gama started his voyage in four ships from the Port of Lisbon with a crew of 170. It was the longest voyage ever attempted in search of a country. They reached the coast of Brazil and from there they travelled to south east. The winds identified by Bartholomeo Dias aided Gama and took him to the southern coast of Africa. However Gama left the place due to disputes with the local government. He sailed past Mombassa and reached Malindi. On sighting Indian merchants there, he sought the help of a local navigator and set sail on 24 April 1498. With the help of the southwest monsoon winds, he reached Kappad near Kozhikode on 20 May after a voyage of 23 days. But Gama struggled a lot when he tried to return during the southwest monsoon season itself neglecting the advice of experts. It took him 132 days to reach Malindi! It was the winds and an unyielding will that helped the mariner named Vasco da Gama to sail thousands of kilometres from Europe to find a sea route to India. The role of winds in that voyage which changed the course of our land's history is worthy of mention. How do winds influence us? Let's look into a few factors like the different types of wind, their formation, and effects. 20 In search of the source of wind  Standard X You have learnt that atmospheric pressure is the weight of atmospheric air and that the variations in the atmospheric pressure are the basic reason for wind. Let's look into the variations behind this and their effects. Variations in atmospheric pressure The average weight that air exerts on the earth's surface is 1034 mg per cm2. The atmospheric pressure is measured using an instrument called Mercury Barometer. It is recorded in units like millibar (mb) and hectopascal (hPa). The level of mercury at normal atmospheric pressure will be 76 cm. The atmospheric pressure at that point will be 1013.2 mb or 1013.2 hPa. Look at the following diagram. Fig 2.1 Did you notice the places marked A and B in the diagram? Which of these places will have a higher atmospheric pressure? Why? Atmospheric pressure and altitude The atmospheric pressure decreases with altitude. The pressure decreases at the rate of 1 millibar (mb) per an altitude of 10 meters. As one goes up, there is a decrease in atmospheric pressure due to the rarification of air with altitude. Why do mountaineers carry oxygen cylinders? 21 In search of the source of wind Social Science II You might have felt your ears clog as you go to high altitude places like Ponmudi, Ooty and Brahmagiri. This is due to the low pressure in these places. The atmospheric pressure and the altitude are inversely proportional. You would have understood now that altitude is an important factor influencing the atmospheric pressure. Apart from altitude, temperature and humidity also influence the atmospheric pressure. Let's see how. Temperature and atmospheric pressure Like any other object, air also expands when it gets heated. The expanded air is less dense and hence it ascends. This leads to the lowering of atmospheric pressure. The ascending air spreads to the sides and it starts cooling. On cooling, it becomes dense and descends. As a result the atmospheric pressure increases. The atmospheric pressure decreases as the temperature increases and vice versa. Haven't you understood now that the temperature and the atmospheric pressure are inversely proportional. Given below are the day and night scenes of a place (Fig.2.2). Fig 2.2 Compare the two pictures. Identify the situations of low and high atmospheric pressure and suitably mark 'H' and 'L' in the pictures. Compared to the colder regions, the tropical regions experience low atmospheric pressure. Why? 22 In search of the source of wind  Standard X Humidity and atmospheric pressure Humidity refers to the quantity of water present in the atmosphere. Water vapour is lighter than air and hence it ascends. If the quantity of water vapour is more in a unit volume of air, then naturally the B atmospheric pressure will be less. Humidity and atmospheric pressure are inversely proportional. Two places at the A Arabean sea Bay of Bengal same elevation are marked as A and B in the figure (Fig.2.3). Which of these has a low atmospheric pressure? Why? Hope you have understood that altitude, temperature and Fig 2.3 humidity experienced in a region influence the atmospheric pressure. Variations in atmospheric pressure occur in accordance with the variations in the above factors. If the atmospheric pressure of an area is higher than that of the surrounding regions, it can be 750 hpa designated as ‘high pressure’ (High - H). In that case, what would low pressure be? 740 hpa You have learnt about the isotherms in the previous 730 hpa classes. Similarly isobars are the imaginary lines joining places having the same atmospheric 720 hpa pressure. We can easily understand the distribution A of the atmospheric pressure of any region by observing the isobars. Observe Fig 2.4. It shows the distribution of 720 hpa atmospheric pressure of a region in two different seasons. 730 hpa Observe the distribution of isobars in the given 740 hpa figure and mark the places experiencing high 750 hpa pressure and low pressure as H and L respectively. B Fig 2.4 23 In search of the source of wind Social Science II Haven't you realized that there can be seasonal 90°N variation in the atmospheric Polar high pressure belt pressure of the same region? Subpolar low pressure belt 60° Global pressure belts Sub tropical high pressure belt 30° Studies have revealed that the atmospheric pressure is more or less the Equatorial low pressure belt 0o same between certain latitudes. Based on this, the earth's surface is divided into Sub tropical high pressure belt 30° different pressure belts. Look at Fig 2.5. Haven't you understood the various Sub polar low pressure belt 60° pressure belts on the Earth? These are known as the global pressure belts. Let's learn about Polar high pressure belt each of these pressure belts in detail. 90°S Fig 2.5 Equatorial low pressure belt Global pressure belts This is the zone where the sun's rays fall vertically throughout the year. Hence the temperature will be high in this zone all through the year. The air expands due to sun's heat and rises up on a massive scale. This is the reason for the low pressure experienced throughout this zone. The equatorial low pressure belt is situated between 5° North and South latitudes. As the air in this zone ascends on a large scale, winds are very feable here. This pressure belt is also known as 'doldrum', meaning 'the zone with no winds'. The region was a nightmare for the ancient mariners. Horse latitude Superior breeds of horses were once a major Sub tropical high pressure belt export from Europe to America and Cargo ships The hot air ascending from the were used to carry them across. As the winds equatorial low pressure belt cools are feeble in the subtropical regions, it was dif- gradually and subsides at the sub ficult for these ships to sail smoothly. In order to tropical zone due to the rotation of the make the ship lighter to facilitate easy voyage, Earth. Hope you now understand the they used to throw many of these horses into reason for the occurrence of high the sea. Thus the zone acquired the name ‘horse pressure all along this zone. latitude’. 24 In search of the source of wind  Standard X Find out the position of the sub tropical high pressure belt from the given figure (Fig2.5). Sub polar low pressure belt Look at Fig 2.5. As this zone is close to the Pole, the air is colder here. Though the cold air remains close to the Earth, the air is thrown away due to the rotation of the earth. As a result, low pressure is experienced all along the sub polar region. Find out the location of the sub polar low pressure belt from Fig 2.5. If the Earth did not rotate, would there have been low pressure in the sub polar region? Polar high pressure belt This zone experiences severe cold throughout the year. As a result, the air remains chilled under the extreme cold that prevails over the Poles, and this contributes to the steady high pressure experienced here. Find out the latitudinal location of the polar high pressure belts. Complete the following table by incorporating the names of different pressure belts and their latitudinal extent. Pressure belt Latitudinal extent You are now aware of the distribution of the pressure belts on the Earth. Variations in the amount of solar energy received and the rotation of the earth contribute to the formation of different pressure belts. The pressure belts shift according to the apparent movement of the Sun. The pressure belts shift northward during the period of Sun's northward progression 25 In search of the source of wind Social Science II and towards the south during the period of its southward progression. Atmospheric pressure and winds Global variations in the atmospheric pressure lead to the formation of winds. The horizontal movement of air from a high pressure zone to a low pressure zone is called wind. There are different types of winds on the earth's surface, ranging from light breeze that makes the leaves flutter to cyclones that cause widespread damage. Winds are named on the basis of the direction from which they blow. For example the south wind is the wind blowing from the south. The peculiarities of the source regions influence the nature of the wind. Winds blowing from the sea will be saturated with moisture whereas the moisture content will be less in winds blowing from drier regions. The speed and direction of wind The speed and the direction of wind are based on Pressure gradient Coriolis force Friction Let's examine them one by one. Pressure gradient Atmospheric pressure is not uniform everywhere on the earth's surface. The change in pressure with horizontal distance is termed as pressure gradient. The pressure gradient is said to be steeper when the pressure difference is more. Fig 2.6 depicts the pattern of isobars in two different situations. Analyse the figures and answer the following questions: 26 In search of the source of wind  Standard X 750 hpa 740 hpa 730 hpa 750 hpa 720 hpa 740 hpa 730 hpa 720 hpa 710 hpa 710 hpa 700 hpa 700 hpa A B Fig 2.6 Mark the direction of winds in both the diagrams, using arrow marks. In which of these situations will the speed of the wind be higher? Why? Coriolis Force Freely moving bodies get deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is due to the force generated as a result of Earth's rotation which is known as the Coriolis force. This force increases as it moves towards the Poles from the Equator. Admiral Ferrel found out that the winds in the Northern Hemisphere deflect towards their right and those in the Southern Hemisphere deflect towards their left due to the Coriolis Effect. The law put forward by him on the basis of this is known as Ferrel's law. 60oN 30o Northern hemisphere 0o Southern hemisphere 30o 60oS Fig 2.7 27 In search of the source of wind Social Science II Friction Look at the given pictures (Fig2.8). In which of these situations do winds blow smoothly? The speed of wind will be high over ocean surfaces and plains as the friction is less. On the other hand, the friction being more along difficult terrains and places with dense forest cover, the speed of wind will be less in those places. Pressure belts and winds You have learnt that there exist differences in pressure over different latitudinal zones at the global level. Fig 2.8 These pressure differences lead to the formation of winds. Winds blow from To prevent desertification high pressure regions to low pressure Trees are often planted along the regions. The winds developed borders of deserts. It is a measure to between the global pressure belts can reduce the speed of the wind thereby preventing the expansion of deserts. be generally called as planetary winds. The different planetary winds Polar high pressure belt are listed below. Polar Easterlies Trade winds Sub polar low pressure belt Westerlies Westerlies Polar easterlies Sub tropical high pressure belt The latitudinal locations of the North east trade winds different pressure belts have been Equatorial low pressure belt identified from Fig 2.5 and marked in South east trade winds Fig 2.9. Sub tropical high pressure belt Haven't you noticed the different Westerlies planetary winds? Sub polar low pressure belt Let's study them in detail. Polar Easterlies Polar high pressure belt Fig.2.9 Global Pressure belts and Planetary winds 28 In search of the source of wind  Standard X Trade winds On the hands of wind… The sub tropical high pressure In the past, the trade belts in both the hemispheres winds that blowed in a can be seen in Fig 2.9. constant direction From here, the winds blow throughout the year continuously towards the were a blessing to those equatorial low pressure belt. transporting goods in These are known as trade winds. ships and other vessels. As these winds blow from the The name 'trade wind' northeast in the Northern might have evolved since it helped ocean trade quite a Hemisphere, they are known as lot. The term 'traden' in German means 'winds that main- northeast trade winds. The tain constant direction'. equatorial low pressure zone where the trade winds from both the hemispheres converge is known as the Inter Tropical Convergence Zone (ITCZ). Find out the direction and the name of the trade winds in the Southern Hemisphere from Fig 2.9. What could be the reason for the trade winds blowing from the southeast and the northeast directions? Westerlies Haven't you seen the sub polar low pressure belts situated between the sub tropical high pressure belts and polar High pressure belts? Winds blow continuously from the sub tropical high pressure zones to these low pressure zones. As the direction of these winds is moslty from the west, they are known NT-483-3-SOC.SCI.-II-10-E-VOL.1 as the westerlies. Identify and note the direction of the westerlies in both the hemispheres from Fig 2.9. The westerlies are stronger in the Southern Hemisphere than in the Northern Hemisphere. This is due to the vast expanse of oceans in the Southern Hemisphere. You read about the route of Vasco da Gama at the beginning of this chapter. It was the 29 In search of the source of wind Social Science II westerlies that helped Gama reach the South Africa through the South Atlantic Ocean. The ancient mariners had given different names to the rough westerlies in the Southern Hemisphere, such as 'Roaring Forties' (along 40° latitudes), 'Furious Fifties' (along 50° latitudes) and 'Shrieking Sixties' (60° latitudes). Polar Easterlies You have learnt that the cold polar regions are centres of high pressure. The polar winds are the cold winds that blow from these high pressure areas towards the sub polar low pressure belts. These winds blow from the East in both the hemispheres due to the Coriolis Force. Hence these are known as polar easterlies. These winds play a significant role in determining the climate of North America, the eastern European countries, and Russia. Prepare a chart describing the planetary winds, the areas where they blow, and their features and exhibit it in the class. You have learnt that the planetary winds are permanent winds blowing between the global pressure belts throughout the year. There are also winds of seasonal and local occurrence. Periodic winds Periodic winds are winds that repeat at regular intervals of time and can be seasonal or diurnal. Monsoon winds are example for seasonal winds. What is monsoon? The term 'monsoon' is derived from the Arab word 'mousom'. It means 'winds that change direction in accordance with season'. Monsoon is the seasonal reversal of wind in a year. The Arab scholar Hippalus was the first to observe the shift in the direction of Monsoon winds. 30 In search of the source of wind  Standard X Many factors are responsible for the formation of the monsoon wind like Meghasandesam, the epic The apparent movement of the sun poem by Kalidasa, is a creative Coriolis force visualization of monsoon winds Differences in heating that change direction according to the season as a messenger. Sun's rays fall vertically to the North of the Equator during certain months due to the tilt of the Earth's axis. This leads to an increase in temperature along the region through which Tropic of Cancer passes. The pressure belts also shift slightly northwards in accordance with this. The southeast trade winds also cross the equator and moves towards the north as the Inter Tropical Southwest Convergence Zone (ITCZ) moves monsoon winds northwards during the summer in the northern hemisphere. As the trade winds cross the Equator they get deflected and are NorthEast monsoon transformed into southwest monsoon winds winds due to the Coriolis Effect. The low pressure formed over the land due to the intense day temperature attracts these sea winds and further contributes to the formation of the southwest monsoon winds. As a result of the formation of high pressure zones over the Asian landmass and low pressure zones over the Indian Ocean during winter, the northeast trade winds get strengthened. These are the North East monsoon winds. Now haven't you understood why the phenomenon called monsoon undergoes seasonal reversal of wind in a year? 31 In search of the source of wind Social Science II Land and sea breeze You have already learnt that atmospheric pressure is different during day and night at the same place. Similarly the reaction of land and sea to Sun's heat is also not uniform. The land heats up and cools down quickly, whereas the sea gets heated up slowly and can retain the heat for a longer period of time. Look at Fig. 2.10. Sea breeze The air in contact with the land also gets heated up and ascends as the land heats up quickly during the daytime. This leads to the formation of low pressure over the land which causes the comparatively cooler air to blow from the sea. This is known as sea breeze. Land breeze As the land cools faster than the sea during Fig 2.10 the night it would be high pressure over the land and low pressure over the sea. This results in the movement of air from the land to sea. This is the land breeze. The Valley breeze land breeze which starts blowing at night becomes active early in the morning and ceases by sunrise. Mountain and valley breeze Look at the figure (Fig. 2.11). These are winds experienced in mountainous regions that are well above the sea level. Mountain breeze During the day time the air above the mountains gets heated and rises up. As a result, the wind blows upslope from the Fig 2.11 valley with relatively lower temperature. This is known as valley breeze. 32 In search of the source of wind  Standard X But during night the air in the mountainous regions cools due to the intense cold conditions in that region. As cool air is dense, it blows towards the valley. This is known as mountain breeze. Local winds Local winds are winds whose effects are limited to a relatively smaller area. Formed as a result of the local pressure differences, these winds are weak. Such winds exist in different parts of the world. Loo, Mangoshowers, and Kalbaisakhi are the local winds experienced in India. Chinook, Harmattan and Foehn are some of the local winds in other parts of the world. Chinook is a hot local wind that blows down the eastern slope of the Rockie Mountains in North America. As a result of these winds, the snow along the eastern slopes of the Rockies melts down? The term Chinook means 'snow eater', an apt term that describes its peculiarity. Since this wind reduces the severity of the cold, it is helpful for wheat cultivation in the Canadian lowlands. Foehn is the wind that blows down the northern slopes of the Alps mountain. As the air heats up due to pressure from the descent, it helps in reducing the severity of cold in that region. Find out from the atlas the countries along the southern slope of the Alps. Harmattan is a dry wind which blows from the Sahara desert towards West Africa. On the arrival of these winds, the humid and sultry conditions of West Africa improve significantly. Hence, people call these winds as the doctor. Loo is another hot wind blowing in the North Indian plain. These winds blowing from the Rajasthan desert raise the summer temperature of the North Indian plains. The winds that blow in South India during this season are called Mango showers. These wind cause the ripening and fall of mangoes and hence the name. 33 In search of the source of wind Social Science II Variable winds Cyclones Variable winds are winds with entirely different characteristics formed during certain atmospheric situations. Cyclones and anticyclones are variable winds. Cyclones Cyclones are caused by the formation of low atmospheric Anti clockwise (Northern Hemisphere) pressure at the centre surrounded by high pressure regions. Strong whirl winds blow towards such low pressure centres from the surrounding high pressure areas. Due to Coriolis effect winds flow in the anti-clock wise direction in the Northern Hemisphere and in the southern Hemisphere. Based on the climatic region of their formation, cyclones can be classified as tropical Clockwise (Southern Hemisphere) cyclones and temperate cyclone. Cyclones often cause extensive damage and destruction wherever they occur. You might have heard of the Ockhi - cyloninc winds that struck the coastlines of Kerala and Lakshdweep during November 2017. This was a tropical cyclone. Tropical cylones are caused due to local pressure differences in Anti Cyclones the tropical oceans, especially the Indian ocean. Ockhi cyclones left the Indian coasts after wreaking havoc on life and property. Prepare a report on the distress caused by Ockhi and suggest measures to mitigate the impact of such disasters in future by collecting information from internet and other Clockwise (Northern Hemisphere) sources. Anti cyclones Anti cyclones are phenomenon where strong whirl winds blow from the high pressure centres to the surrounding low pressure areas. Due to Coriolis effect the pattern of winds in anti cyclones is clock wise in the Northern Anti clockwise Hemisphere and anti clockwise in the Southern (Southern Hemisphere) Hemisphere. 34 In search of the source of wind  Standard X Complete the following flow chart showing the classification of winds. Winds Planetary winds Local winds........................................ Variable winds........................... Cylcones Loo Monsoon........................................................................................................................................................................................................................ The Sun's aura Don't you now realize how dynamic the earth's atmosphere is? The driving force behind this continuous movement of air is the Sun. Without its energy there would be no temperature or pressure difference, or any wind. The role of the atmospheric phenomena in keeping the earth's surface dynamic is immense. Information on the diversities in the nature not only arouses our curiosity but is informative as well. May all of you be able to continue your quest regarding the Earth and its diversities. Let us assess Temperature, altitude and humidity are inversely proportional to atmospheric pressure. Justify. Prepare notes on the role of solar energy and the Earth's rotation in the formation of pressure belts. Describe how the Coriolis Effect causes the deflection of winds on the basis of the direction of the winds mentioned below. a. Trade winds b. Westerlies 35 In search of the source of wind Social Science II Observe the pictures. Who all can be seen and what jobs are they engaged in? Which are the goods and services made available as a result of these efforts? List in the table the different jobs and the goods and services produced by them. Taxi driver Arranges transportation Farmer Produces agricultural crops 36 Human Resource Development in India  Standard X Manpower is an important factor in making available the above mentioned goods and services. Therefore, human resource is necessary for the progress of any country. Let us examine some aspects of human resource development and its status in India. Human resource Many goods and services are necessary for improving human life and for the progress of a country. To facilitate this the manpower of many has to be utilised. Human resource refers to people who have the manpower which can be utilised in the production sector. Increase in production and progress of a country can be accelerated only if the human resource is developed to the maximum. How can human resource be developed? Human resource development is the development of man's physical and mental abilities through education, health care, and training. There are different levels of human resource development. Individuals take efforts to develop their own skills. Family creates an environment for the development of the potential of individuals. Various institutions and agencies provide facilities for education and training. Nation provides the necessary facilities for its people to develop their skills. Prepare a note on the facilities provided in your area for the development of human resource? Features of human resource What features are to be considered while studying human resource? Human resource has quantitative as well as qualitative features. Examine the chart given below. 37 Human Resource Development in India Social Science II Human Resource Quantitative features Qualitative features Size of Growth of population Population Education Health population structure care Population density Birth rate Death rate Literacy rate Life expectancy Age structure Sex ratio Labour force participation rate Dependency ratio Hope the qualitative and quantitative features of population are clear from the given chart. Let us analyse the quantitative aspects. Size of population Size of population refers to the total number of people residing in a country at a particular time. The branch of social science that analyses the population, the changes in its size, its structural aspects, etc is known as demography. Every country collects information on the number of people in the country, their age, sex, socio - economic status, etc. and analyses these at specific intervals of time. This activity is known as population census. In India, census activities are spearheaded by the Office of the Population Registrar General and Census Commissioner. In India, population census is conducted once in ten years. The last census was conducted in 2011. Information related to the population were collected as on 1 March 2011. According to this census there are 121.02 crore people in India. Out of this, 58.65 crore are females and 62.37 crore are males. Why are population studies conducted? Population studies help the government to quantitatively assess the different needs of the people and to plan activities and programmes accordingly. What other help do they offer? 38 Human Resource Development in India  Standard X Informs the availability of human resource in a country. Depicts the extent of basic facilities required by the people. Quantfies the goods and services required. Determines the socio - economic development policies. Find out from your elders what information was collected from your home for the 2011 census. Collect more information on the population by visiting the website www.censusindia.gov.in According to the United Nations Organisation Report 2014, the world population is 724.4 crores. One in six person of the world population is an Indian. 17.5 percentage of the world population is in India. China ranks first in position with 19.4 percent and India ranks second. In terms of land area, India ranks seventh with only 2.4 percent. India and China can play a major role in making human resource available. It has been proved by the experience of countries like the USA, Japan, and China that a nation can attain high economic development through better human resource development. Density of population Inhabitation is not the same everywhere in India. We have already understood the factors that influence July 11 population. Density of population refers to the World Population Day number of people per square kilometer area. This UNDP has declared 11 July as differs in various states in India. the World Population Day How does the population density of an area since 1989 and is observed. influence the availability of human resources? This day was selected because Discuss. the world population reached 500 crore on July 11, 1987. Population growth rate in India Population growth refers to the increase in the number of people in an area within a specific period of time. It is 39 Human Resource Development in India Social Science II indicated in terms of percentage and states the increase in a year as compared to the previous year. Examine the table indicating population growth rate in India. Decadal growth rate Year Population (in crores) (in percentage) 1951 36.11 13.31 (1941 - 51) 1961 43.90 21.64 (1951 - 61) 1971 54.82 24.80 (1961 - 71) 1981 68.33 24.66 (1971 - 81) 1991 84.64 23.87 (1981 - 91) 2001 102.87 21.54 (1991 - 2001) 2011 121.02 17.64 (2001 - 11) Source : Census of India 2011 (Provisional) Which decade has marked the maximum population growth? From which year onwards is there a decrease in the population growth rate? How much decrease did the population growth rate record in the decade 2001-2011? It can be seen that India's population growth rate has been declining since 1971. The birth rate, death rate, and migration are the factors that affect the population of a country. Observe the chart given below. Birth rate increases Population increases Death rate decreases Birth rate decreases Population declines Death rate increases Birth rate and death rate are No change in population equal Population increases in one Migration region but decreases in another region Birth rate Death rate Birth rate is the number of live births per Death rate is the number of deaths per 1000. 1000. Migration Migration is the settlement of people of a region in another region. 40 Human Resource Development in India  Standard X What changes are made in the population of a country by birth rate, death rate, and migration? Prepare a note. Population Structure Age structure is the classification of population into different age groups and presenting the ratio of each group in the population. For example, classification is done in age groups like 0- 14 years, 15-59 years, and 60 and above years. Given below is the age structure based on Census of India 2011. Population : Age Structure Distribution Source : Census of India 2011 What percentage of the total population belongs to the age group of 0-14 years? What percentage of the total population belongs to the age group of 60 years and above? What percentage of the total population belongs to the age group of 15-59 years? Labour force participation rate is the ratio of the population in the age group 15 - 59, who are either employed or actively looking for jobs. This age group has the capability to contribute to the progress of the nation. The age groups 0- 14 years and 60 years and above are included in the dependent group. Their proportion in total population is known as dependency ratio. This group depends on the working force of the country. An increase in the dependency ratio decreases the per capita income. 41 Human Resource Development in India Social Science II Many people in the age group 15 - 59 years do not have a job. This points to the necessity of utilising the human resource aptly. Discuss the problems in the economy as a result of a decrease in the labour force participation rate and increase in the dependency ratio? The sex ratio plays an important role in determining the human resource of a country. According to census 2011, the sex ratio in India is 940. Sex ratio is the number of females per 1000 males. Conduct a discussion in class on the topic sex ratio and the nation's economic development. So far we have discussed the quantitative aspects of the population. There are certain aspects that improve the quality of human resource. Let us look at them. Qualitative aspects of human resource The population that can contribute to the manpower of the nation is its strength. What are the qualitative factors that improve the labour potential? Education Healthcare Training Social capital Let us see the advantages in developing human resource. Observe the diagram. Productivity of the workers Economic inequality increases is reduced Entrepreneurship Improved Natural resource is utilized improves human effectively resource Makes possible the development Social welfare is and use of advanced ensured technology 42 Human Resource Development in India  Standard X Prepare a note on how human resource development helps in economic development. Lets observe how each qualitative factor improves human resource. Education and human resource development A mere increase in the population will not lead to the development of a country; it requires people with potential and skills. Education has a major role in moulding skilled people. Let's see how education helps in the development of a country. Observe the flowchart. Education Improves the skills Ministry of Human Resource of individuals Development In India, a department operates for Betters the technological human resource development. The know - how Government of India started this department in the year 1985. The main responsibility of this department is to Helps to secure better job and income plan and implement the activities necessary for human resource development. Improves the standard of living Experts argue that at least 6% of the national income must be spent for providing facilities in the education sector. During the year 2017 - 18 Government of India spent only 3.7% of the Gross Domestic Product (GDP) on education. Hence the literacy rate could not be improved along the expected lines. Observe the table given below. India : Literacy rate Female 65.46 Male 82.14 Total 74.04 Source : Census of India 2011 43 Human Resource Development in India Social Science II Literacy rate refers to the percentage of population that can read and write with comprehension. Let us see the projects implemented in India to develop education and skills. Projects Goals To ensure integrated development of Integrated Child children upto 6 years Development Scheme To provide healthcare for pregnant and (ICDS) lactating women To ensure universal education to all up Samagra Shiksha to higher secondary level Abhiyan (SSA) To ensure quality and equity To promote the vocational education strenthen Samagra Shiksha was formed by integrating To the teacher training institutes like Sarva Shiksha Abihyan SCERT/DIET (SSA) and Rashtriya Madhyamik Shiksha Abhiyan (RMSA) Rashtriya Uchthal To increase the access to higher Shiksha Abhiyan education (RUSA) To improve the quality of higher education National Skill To improve the working skills of the Development and youth Monetary Reward To ensure the availability of people with Scheme employable skills Apart from these, several programmes are also initiated by state governments. Prepare a report by collecting details about the different educational development programmes undertaken by the state and local government institutions in Kerala. 44 Human Resource Development in India  Standard X There are institutions at various levels to provide education in a country. Schools, colleges, universities, technical education National Skill Development institutions, etc are among them. Corporation (NSDC) Our country has made education a fundamental right and has passed the In order to compensate the shortage of Right to Education Act (RTE Act) in 2009. skilled people, the NSDC has been The constitution ensures the goal of giving skill training in various fields such "elementary education for all" through as construction, tourism, banking, and RTE. engineering. However, problems still exist in the education sector of India which need to be solved. Certain sections drop out from schools without completing primary education. There is a lack of availability of basic facilities in the education sector. Quality of education has to be improved. Conduct a discussion on the topic 'Educational facilities in India and the existing problems'. Human resource development and healthcare What is health? According to the World Health Organisation (WHO), health is a state of physical, mental and social wellbeing. Along with physical conditions, importance is given to mental and social conditions as well. It is the government's responsibility to ensure healthcare for all. Only then can each individual work for the economic development of a country. Let us see how healthy persons can participate in the progress of a country. Production increases with the increase in efficiency and the number of working days. Natural resources can be utilised properly. Medical expense can be reduced, thereby reducing the government's expenditure. 45 Human Resource Development in India Social Science II Economic development is possible through increase in production Let's list the facilities to be ensured for healthcare. Availability of nutritious food Availability of clean water Preventive measures Cleanliness Medical facilities Ensuring of leisure and entertainment Healthy environment Various institutions operate to ensure the availability of the above - mentioned facilities. The government has set up institutions that work at different levels in the medical sector. All India Institute of Medical Sciences Medical Colleges AIIMS has been es- tablished to make District Hospitals available the services of the best doctors Community Health Centres and modern medical Primary Health Centres facilities. Now there are 9 such institutions working in different parts Health Sub Centres of the country. Discuss how the different institutions working in the health sector help in making available the medical attention and preventive measures to the people. There are various hospitals in the cooperative and private sectors. Many multispecialty hospitals operate to make available modern treatment facilities. There are several institutions which provide different systems of medicine like ayurveda, yoga, naturopathy, unani, sidha and homeopathy; National Rural Health Mission (NRHM) and National Urban Health Mission (NUHM) function to make available quality 46 Human Resource Development in India  Standard X health services to all. The National Rural Health Mission operates in the rural sector. The National Urban Health Mission provides improved health services to the residents of urban slums and other marginalised people in towns with a population of more than 50,000. As a result of these programmes and activities, the life expectency in India has been improved. Observe the table below. India : Life expectancy Female 67.7 Male 64.6 Total 66.1 Source : Census of India 2011 Life expectancy is the expected average years of life of a person lives. Organise a seminar on the topic 'The role of education and healthcare in human resource development'. Various resources are to be used properly for the economic development of a country. We have understood that human resource is as important as natural resources. When the natural resources are combined with human efforts there is an increase in production leading to economic development. Therefore, planned efforts are required in the education and health sectors to develp human resource. Only then can resources then can the quality and development of human resource be attained. Do you agree with the statement that the main reason for prosperity and poverty in the world is the difference in human resource development? Prepare a note. Let us assess List out the quantitative and qualitative aspects of human resource? Prepare a note by analysing the importance of population studies. 47 Human Resource Development in India Social Science II Compare the changes in population due to birth rate, death rate and migration. Labour force participation rate and dependency rate as per the census of India 2011 is given below. Prepare a graph based on this. Labour force partici- Dependency rate pation rate (in percentage) (in percentage) Female 62.8 37.2 Male 62.2 37.7 List the advantages of the increase in labour force participation rate and disadvantages due to increase in dependency rate. What are the factors that improve human resource? How does this influence a country's development? How does education help in a country's development? Prepare a flowchart. List the existing problems in the health sector. Explain how education and healthcare help in human resource development. Extended activities Visit the website of the Census India and collect the latest population data. Organize various programmes in connection with the World Population Day. Find out the dependency rate and the labour force participation rate by collecting the age structure from the families of your classmates. Prepare a report by interviewing the headmaster on the programmes which are undertaken by the school to improve the quality of education. 48 Human Resource Development in India  The British realized that they could ascertain power and collect the taxes in their colonies only if they clearly understood the special geographical features of each of them. This made them decide to conduct various surveys and Col. William prepare maps on their basis. Accordingly three surveys namely George Everest Lambton the Tax Survey, the Topographic Survey, and the Trigonometric survey were carried out by the East India Company in the Indian subcontinent. These surveys that were began with the stewardship of Col.william Lambton in 1802 which took more than 50 years to be completed, were very accurate. Several Indians were part of these surveys conducted through difficult terrains and hostile climate, carrying the heavy metallic survey instrument called theodolite which weighed half a ton. The surveys incurred immense expenditure and took a toll on many. Col. George Everest joined as an assistant to Lambton in 1818. This was the first survey that recorded the correct measurements of the Himalayan mountain ranges. As a tribute to George Everest who took up the survey as Lambton's successor the highest peak in the Himalayan mountain ranges was named as Mount Everest. The first topographic maps of the Indian subcontinent were prepared after the completion of the survey in 1854. Social Science II Haven't you read the above description? Finding the precise location of the earth's surface features is essential for the preparation of maps. Each part of the earth is measured with the help of survey instruments and maps are prepared based on these measurements. What are the features of the topographic maps? How do these differ from other maps? Let's look into these aspects. Topographic Map You have learnt that large scale maps are prepared by