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»1 https://t.me/UPSC_PDF www.UPSCPDF.com https://t.me/UPSC_PDF. « - 1 I i * t — m i i i i - A. w — t t" - * r f - ii - f y 1 - C. hr H. “. ' L 1 - r ::. i *. - i V m- - i i -r-r-. “ ~ 1 7 y V * OXFORD OXFORD WJlllllll INDIAJ I N D I A ** / n fi r H rLi u I. -I * I - 1| Google it:- www.UPSCPDF.com l + https://t.me/UPSC_PDF www.UPSCPDF.com https://t.me/UPSC_PDF Acknowledgements Contents Preface following for The author and publishers are grateful to the Part 1. Physical Geography permission to reproduce copyright photographs : Radio Metric Conversion Table v 7. Arid or Desert I.andforins Part 2. Weather. Climate and Vegetation Times. Camera Press. Jabatan Penerangan Malaysia. G. C. PART I PHYSICAL GEOGRAPHY Types of Deserts, 55; The Mechanism of Arid Ero¬ the This second , revised edition carefully follows Morgan. Philippine Tourist and Travel Association. Paul sion , 56 Landforms of Wind Erosion in Deserts. recent syllabus. The book is illustrated with maps,. Popper Swiss National Tourist Office. J. K St Joseph U.S. 1. The Earth and the Universe 1.. 57; Landforms of Wind Deposition in Deserts. 59: diagrams, graphs and photographs. The illustrations Information Service, Australian Tourist Commission. Exploring the Universe. 1 : The Solar System, 1 : Landforms due to Water Action in Deserts. 60: have been carefully drawn to assist students in their Institute of Geological Science. S.T. Fok , N.Z. High 'TThe shape of the Earth. 2. Evidence of the Earth 's Questions and Exercises, 61. interpretation of geographical facts presented in the Commission Malaysia, Royal Netherlands Meteorological Sphericity. 2: The Earth 's Movements. 4: Day and book. Local examples have been quoted wherever. Institute. Meteorologie National Paris J. Mondaine. Royal Night. 4; The Earth’s Revolution, 5: Dawn and 8. Limestone and Chalk Landforms possible. Observatory Hong Kong, Government Information Services Twilight. 6; Mathematical Location of Places on Limestone and Chalk , 62; Characteristic Features Part 2 on world climatic types and natural vegeta ¬ Hong Kong. Primary' Production Department Singapore, the Globe. 7; Latitude. 7; Longitude, 8; Longitude of a Karst Region, 62: The Major Limestone Reg ¬ tion also includes the economic development of the Australian News and Information Bureau. J. Allen Cash. and Time. 8; Standard Time and Time Zones, 9: ions of the World , 64; Human Activities in Karst natural regions. The more important agricultural S.E. F. Torino, National Film Board of Canada. Press The International Date Line, 10: Questions and Regions, 64: Question and Exercises, 65. activities of each region have been treated in greater Information Bureau India. Central Office of Information Exercises, 10; Selected Cambridge Questions. 11. 9. Lakes 66 London. Elizabeth Meyer, Walkabout. Ministry' of Culture General , 66: The Formation and Origin of Lakes. detail. Singapore. Standard Triumph. United Nations and Society 2. The Earth’s Crust 12 To assist the student key words, facts and head - , for Cultural Relations with U.S.S. R. The Structure of the Earth , 12; The Classification 66: Lakes and Man , 69; Questions and Exercises. ings-have been printed in colour. In addition , five Acknowledgements are credited with their respective of Rocks, 12; Igneous Rocks, 12 Sedimentary 71. questions are included in each chapter. reproductions in the book. Every effort has been made to Rocks, 13 Metamorphic Rocks. 13: The Influence 10. Coastal Landforms I wish to express my heartfelt thanks to Mr. Khoo contact the holders of copyright to the reproductions, but of Rock Types on Landscape. 14: Earth Move¬ The Action of Waves, Tides and Currents, 72; The Peng Seong B.A.. Dip. Ed. , F. R. G.S. for his proof in some cases without success. To these, the author and ments and the Major Landforms, 14; Types of Mechanism of Marine Erosion , 72; Coastal Fea ¬ reading, the editiorial staff of O. U. P. for valuable publishers offer their apologies, trusting that they will accept Mountains, 14; Types of Plateaux. 17; Types of tures of Erosion. 73; Coastal Features of Deposi ¬ assistance throughout the production of the book and the will for the deed. Plains, 18. tion. 75; Types of Coasts, 76; Coastlines of the various authors and friends who have so gene ¬ Emergence. , 77; Questions and Exercises. 78. 3. Vulcanism and Earthquakes 20 rously helped me. Landforms Associated with Vulcanic Activities, 11. Islands and Coral Reefs 79 Goh Cheng Leong 20; Landforms of Igneous Intrusions, 20; The Ori ¬ General. 79; Coral Reefs. 80; Types of Coral OXFORD gin of Volcanoes, 21; Types of Volcanoes. 22; Reefs, 81 ; The Probable Origin of Coral Reefs. 82; UNIVERSITY PRESS Extrusive Landforms, 22; Some Volcanic Erup ¬ Questions and Exercises 83. Oxford University Press is a department of the University of Oxford tions, 23; The Distribution of Volcanoes in the 12. The Oceans 84 It furthers the University's objective of excellence in research, scholarship, 56 Jalan and education by publishing worldwide. Oxford is a registered trademark of World , 24; Geysers and Hot Springs, 25; Ear¬ Exploring the Oceans, 84; The Relief of the Dato Khong Kam Tak Oxford University Press in the UK and in certain other countries thquakes, 26; Some Major Earthquakes, 26: The Ocean. 85; The Deposits of the Ocean Floor. 86; Harimau (Tiger Lane) Distribution of Earthquakes, 26: Questions and Salinity of the Ocean. 86; The Temperature of Published in India by Ipoh Perak Oxford University Press Exercises, 26. Ocean Water, 86; The Movements of Ocean Cur¬ Malaysia.. YMCA Library Building 1 Jai Singh Road New Delhi 110001 India. 4. Weathering, Mass Movement and Groundwater rents, 87; The Circulation of the Atlantic Ocean. © Oxford University Press 1974 28 88 ; The Circulation of the Pacific Ocean. 89; The Bangunan Lokc Yew, Kuala Lumpur Weathering, 28; Mass Movement , 31 ; Groundwa ¬ Indian Ocean Circulation , 90; Questions and ter, 33; The Water-Table, 34; Springs and Wells, Exercises, 90; Selected Cambridge Questions. 91. The moral rights of the author have been asserted 35: Questions and Exercises, 37. First published 1974 5. Landforms made by Running Water 38 PART 2 WEATHER, CLIMATE AND 43rt impression 2014 The Development of a River System; 38: The VEGETATION. All rights reserved. No part of this publication may be reproduced , stored in Mechanism of Humid Erosion. 38; The Processes 13. Weather a retrieval system , or transmitted, in any form or by any means, without the of River Action , 39; River Erosion and Transpor¬ 93 prior permission in writing of Oxford University Press, or as expressly permitted T he Difference between Climate and Weather, 93: by law, by licence or under terms agreed with the appropriate reprographics tation , 39; The Course of a River 40; River The Elements of Weather and Climate, 94: Rain ¬ rights organization. Enquiries concerning reproduction outside the scope ol the Rejuvenation , 44; The Human Aspects of Rivers. fall , 94; Pressure. 95: Temperature, 96: Humidity.. above should be sent to the Rights Department Oxford University Press , at the 45; Questions and Exercises, 45. address above 98; Winds. 98: Sunshine, 99: Clouds, 100; Other 6. Landforms of Glaciation 47 Elements Pertaining to Visibility, 104 ; Questions i The Ice Age and Types of Ice Masses. 47; Land - and Exercises, 104. I You must not circulate this work in any other form and you must impose this same condition on any acquirer forms of Highland Glaciation, 48; Landforms of 14. Climate Glaciated Lowlands; 51 ; Human Aspects of 105 1 The Atmosphere. 105; Insolation. 105; Elements - -- - ISBN 13: 978 0 19 562816 6 - Glaciated Landforms, 53, Questions and Exer¬ | - - ISBN 10: 0 19-5628160 cises, 54. of Climate and Factors Affecting Them. 106; I. Printed in India by Tara Art Printers Pvt. Ltd. Noida 201301 Temperature. 106: Factors Influencing Tempera - I Google it:- www.UPSCPDF.com i https://t.me/UPSC_PDF www.UPSCPDF.com https://t.me/UPSC_PDF. tion, 144; Economic Development of the Mediter ¬ Precipitation. 108; Rainfall 108. Pressure. ture 106; Breezes ranean Regions, 145; Questions and Exercises, and Planetary Winds. 109; Land and Sea \ in 147. a and Monsoons. I l l; Fohn Wind or Chinook an 20. The Temperate Continental (Steppe) Climate 111; Cyclonic Activity, 112; Climatic Types - j- 8 Natural Vegetation. 113; W orld Climatic ; Types. 148 S 114; Questions and Exercises. 115; Selected Cam ¬ Distribution, 148; Climate, 148; Natural Vegeta ¬ : j- S bridge Questions, 115. tion, 150; Economic Development, 151; Questions. 2 6 and Exercises, 153. c s -r 15. The Hot, Wet Equatorial Climate Distribution. 116; Climate, 116; Vegetation , *' 118,. 21 The Warm Temperate Eastern Margin (China :b § b 155 Factors Affecting the Development of Equatorial Type) Climate Distribution, 155; Climate , 155; Natural Vegeta ;r 8. Regions 119; Questions and Exercises, 120. Economic Development, 158; Question ¬ 8 b? 16. The Tropical Monsoon and Tropical Marine tion, 158 ; Climates 122 and Exercises, 161. Distribution, 122; Seasons of the Tropical Mon 22. The Cool Temperate Western Margin ( British Randainfl ba ¬ soon Climate, 123; The Retreating Monsoon. 124;. Type) Climate. , 163 Natural 163 Vegeta 3 H i Tropical Marine Climate 124; Tropical Monsoon Distribution 163; Climate ; s ¬ 8 cn|ir> -— 2 1 Forests, 124; Agricultural Development in Mon ¬ tion, 165; Economic Development, 165; Questions II ST soon Lands, 125; Question and Exercises, 127. and Exercises, 169. L a CM 17. The Savanna or Sudan Climate 129 23. The Cool Temperate Continental (Siberian) s -ib a ^ II 1 3 o § ? o II II «3 Tempratue Distribution, 128; Climate of the Sudan Natural Vegetation. 129; Animal Life of Type. 128; Climate 170 s I T[ - 4 o * II | 1 ! tons 1 1 metric the Distribution, 170; Climate, 170; Natural Vegeta ¬ (0 Savanna. 130; Human Life in the Savanna, 131; tion, 172) Economic Development, 173; Ques ¬ :r 8 8 LL i 11 E i « S r-o £ S' Q CO CM £ § 2 s s Problems, Prospects and Development of the Savanna. 132; Question and Exercises, 133. tions and Exercises, 175.. 24 The Cool Temperate Eastern Margin (Lauren- r- 8 C 0 £ ® ® w § o JN ^ o o. § - r S Tj evi - ^^ CM rf o c\i ID 3 g w 3 1.016 18. The Hot Desert and Mid-Latitude Desert Cli¬ tian) Climate 176 ? 4 -8 II II n II II II II II II II II II - g & mates Distribution, 134; Climate, 134; Climatic Condi 134 ¬ Distribution, 176; Climate, 166; Economic Development, 178; Fishing, 179; Questions and for ;j 2 a iI i II !- !! 1 2 B 1 81 Exercises, 181. I— -2 1 ! 2 Scales tions in the Mid-Latitude Deserts, 136; Desert ° Vegetation, 136; Life in the Desert, 137; Ques a-i " II H 25. The Arctic or Polar Climate 183 Soo 1 ¬ ® II :b ? tions and Exercises, 140. 19. The Warm Temperate Western Margin Distribution, 183; Climate, 183; Tundra Vegeta tion, 184; The Importance and Recent Develop ¬ 8 Jr 8 - | 1 si I? 8 I 1I c ib : ¬ ? Cversion (Mediterranean) Climate 141 ment of the Arctic Region, 185, Questtions and s- iS 1 Distribution, 141; Climate, 141; Natural Vegeta ¬ Exercises, 186; Selected Cambridge Questions, :f St " 5 II J 8 «t» 186. :r : o II :L I ? bb ? :j- s i - ! ? lh § § :r ih ? I :r ? :: § 2 :b ? § S v -- § :r : V i s * Google it:- www.UPSCPDF.com https://t.me/UPSC_PDF www.UPSCPDF.com https://t.me/UPSC_PDF Chapter 1 The Earth and the Universe Exploring the Universe leap up in whirls of glowing flames like a volcano On a fine bright night when you look up at the sky in eruption. In size, the Sun is almost unimaginable. it seems to be studded with stars. Little do you It is about 300,000 times as big as the earth! realise that each of the stars is far bigger than the Amongst the nine planets, Mercury is the smallest earth on which we live. Some of the larger ones and closest to the sun, only 36 million miles away. have been estimated to be many millions of times the It thus completes its orbit in a much shorter space size of the earth. These stars are not scattered of time than does Earth. A year in Mercury is regularly in space; they occur in clusters, better only 88 days. Venus, twice the distance away from described as galaxies or nebulas. Each galaxy may the sun , is the next closest planet. It is often con ¬ contain as many as 100 million stars. It is believed sidered as ' Earth' s twin because of their close that the earth’s own galaxy ( the Milky Way ) alone proximity in size, mass ( weight ) and density. But no Part 1 : Physical Geography contains as many as 100,000 million stars. The stars appear small to us even through a other planet is in any way comparable to Earth which has life and all the living things we see around us. telescope because they are so far away. The light Like many other planets, the Earth has a natural from the nearest star travelling at the speed of light satellite, the Moon, 238,900 miles away, that revolves (i.e. 186,000 miles per second) takes something like eastward around the Earth once in every 27 days. four years to reach us. A ray of light from the sun The fourth planet from the sun is Mars which takes about eight minutes to reach the earth. Light , has dark patches on its surface and is believed by takes only a second to reach us from the moon. most professional astronomers to be the next planet after Earth to have the possibility of some plant The Solar System life. Much attention has been focused on Mars to The solar system comprises the Sun and its nine explore the possibilities of extending man’s influence planets ( Fig. 1.) which are believed to have been to it. Next comes Jupiter, the largest planet in the developed from the condensation of gases and other solar system. Its surface is made up of many gases lesser bodies. All the planets revolve round the Sun like hydrogen, helium, and methane. It is dis¬ in elliptical orbits. Like the earth, they shine only tinguished from other planets by its circular light by the reflected light of the sun. The Sun has a and dark bands, and the twelve satellites that circle surface temperature of 6,000°C. (10,800°F.) and round it. As it is more than 485 million miles from increases to 20 million°C. (36 million°F.) in the the Sun, its surface is very cold, probably about interior. All over its surface are fiery gases that -200°F. (-130°C.).. O stance from tun to planet.. 4,S66.000 000m le« 1.783,000.000 miln. 485.000 000 mile* -- I - 93.000.000 mile* SUN. X 000.000 mile* MERCURY Q 4^ © 9"“ °" ° ° ° ° ° Cd} oQ ° ° 9? VENUS EARTH MARS JUPITER SATURN URANUS PLUTO % 1 The Solar System— the Sun and the nine Planets Google it:- www.UPSCPDF.com I https://t.me/UPSC_PDF Evidence of the Earth's Sphericity www.UPSCPDF.com https://t.me/UPSC_PDF There are many ways to prove that the earth js A FLAT EARTH V / 4 spherical. The following are some of them. \ 1. Circum-navigation of the earth. The first voyage 4 ^ / \ Sun that it takes The scventh £" not known to around the world by Ferdinand Magellan and his / \ it was firs ^ JdJ a efaintla e bluish ’. lescope eighteenth “ L it is another planeth. [. - hand 5 limes century green disc giant aS w hen throug heav, ' crew, from 1519 to 1522 proved beyond doubt that the earth is spherical. No traveller going round the world by land or sea has ever encountered an abrupt edge, over w'hich he would fall. Modern air routes / I v\ A FLAT EARTH Unlike other planets. Uranus orbits around the sun and ocean navigation are based on the assumption “7 clockwise direction front east to west with five that the earth is round (Fig. 2). HORIZON satellites revolving round it. Fig. 4 ( b) A flat earth, the entire ship is seen at once The two outermost planets in the solar system. A CURVED EARTH on a flat surface Neptune and Pluto are just visible with telescopes Fig. 3 ( a ) Increasing altitude widens the circular hori ¬ Their discoveries were the result of mathematical zon. Viewed from Y the horizon would be calculations on their irregular gravitational effects AB but from a higher viewpoint ( X ) a wider 4. Sunrise and sunset. The sun rises and sets at on neighbouring planetary bodies. Neptune closely horizon ( C, D ) would be seen different times in different places. As the earth resembles Uranus, except that it has only two known f rotates from west to east , places in the east see the satellites and is probably much colder. Pluto is sun earlier than those in the west. If the earth were smaller than Earth. As the orbits of the planets are EAHTH (spherical) A VIEW POINT flat , the whole world would have sun. i e and sunset at the same time. But we know this is not so. not circular but elliptical, the distance of Pluto from the Sun during perihelion (i.e. when it is closest to / \ Y VIEWPOINT ^ , Fig. 5 illustrates this. I , /. the Sun) is 2,766 million miles, and at aphelion (i.e. when it is farthest from the Sun) is 4, 566 million / ^ ^ \ ' - miles. A year in Pluto is no less than 247 years on * HOR ZON B earth! Due to their very recent discovery and their extreme remoteness from the earth , very little is so far known about these last two planets. Fig. 2 (a ) Circumnavigation of the earth The Shape of the Earth In the olden days, sailors feared to venture the distant ocean because they thought far into was as flat as a table. They thought the earth & ( b) Visible horizon remains the same regardless that when they of altitude. If the earth were flat the reached the edge of the earth , they would and perish in the bottomless slip down horizon seen from either Y or X would be ocean. This is, of the same course, not true. From years of ledge, experience and observ accumulated know¬ 4 ations in different parts DRC gradual. If the earth were flat , the entire ship would Fig. 5 (a) Sun rises and sun sets at different times of the world, we know that be seen or obscured all at once. This is apparent for different places the earth is round. Its spherical shape is an establ from Fig. 4. ished fact, proved, and accepted by all. There has been so much research done on earth science that ( b ) Abrupt drop at the have been accurately found its various dimensions edge of a table - like A CURVE D EARTH earth circumference of 24,897 milesIt and has an equatorial. 2. The circular (t)0S ^ line of sight cumference is less by 83 miles - its polar cir¬ horizon. The distant horizon viewed from the deck of a ship 4 diameter is 7,926 miles and. Its equatorial on land is always and at sea , or from a cliff shorter by 26 miles. This its polar diameter is everywhere circular in shape. simply shows that the This circular horizon widen earth is not a perfect and could only be seen s with increasing altitude sphere. It is a little on a spherical body. This both ends like an flattened is illustrated in Fig. 3. A SPHERI CAL EARTH called a geoid (‘earth orange. It can, in fact, be of the earth is -sha also masked hv lands and oceans on ^ ^ its surface fft thJ ? “ The nh h m ervenmg blgb * * ' ]' Ship’s visibility - d,stant horizon < the top a shiP appears over the of the mast is seen first before |he hull. In the same way, when it leaves harbour, its disappearance F 9 - 4 (a ) The mast of a ship is seen before the hull over the curved surface is equally ' (b) The whole world will have sun rise or sun on curved horizon set at the same time Google it:- www.UPSCPDF.com 3 T " | https://t.me/UPSC_PDF www.UPSCPDF.com https://t.me/UPSC_PDF cast by the The lunar eclipse. The shadow eclipse is always earth on the moon during the lunar circular. It takes the outline of an arc of a circle. Only a sphere can cast such a circular shadow. 6. Planetary bodies are spherical All observations. K L ( Moon ) , from telescopes reveal that the planetary bodies the Sun. Moon, satellites and stars have circular outlines from whichever angle you see them. They are strictly spheres. Earth , by analogy, cannot be Fig. 7 (a ) Kuala Lumpur emerges from darkness the only exception. 7 Driving poles on level ground on a curved earth.. 3* into daylight at sun rise when the earth rotates into the sun's rays Engineers when driving poles of equal length at VVnr ( b ) The sun is directly overhead at Kuala Jp regular intervals on the ground have found that they Lumpur or midday do not give a perfect horizontal level. The centre ( c ) Kuala Lumpur passes from daylight into pole normally projects slightly above the poles at darkness at sunset when the earth rotates either end because of the curvature of the earth , as away from the sun ( d ) Kuala Lumpur is directly away from the illustrated in Fig. 6. Surveyors and field engineers sun at mid - night therefore have to make certain corrections for this inevitable curvature, i.e. 8 inches to the mile. - or 66,600 m.p. h. One complete revc ’ ution takes 365{ days or a year. As it is not possible to show MOW poto prefect* abw ocmn a quarter of a day in the calendar, a normal year is taken to be 365 days, and an extra day is added every four years as a Leap Year. 1. Varying Lengths of Day and Night ST The axis of the earth is inclined to the plane of the. The earth viewed from the moon. ecliptic ( the plane in which the earth orbits round vm*ocji *««*1 " T» The picture was the sun ) at an angle of 663°, giving rise to different 5so^ ’ taken on the Apollo seasons and varying lengths of day and night ( Fig. 8). r 8 mission of 1968 If the axis were perpendicular to this plane, all parts Fig. 6 (a ) The centre pole projects well which prepared the above the way for the moon of the globe would have equal days and nights at poles at either end on a curved surface landing all times of the year, but we know this is not so. Sfv Camera Press In the northern hemisphere in winter ( December) as we go northwards, the hours of darkness steadily ** 2°** « ths unw fe« the sun and experiences daylight. The other portion increase. At the Arctic Circle (664° N.), the sun The Earth 's Movement which is away from the sun’s rays will be in darkness. never ‘rises’ and there is darkness for the whole day POLES Man is always conscious of the ' apparent movement As the earth rotates from west to east , every part of in mid-winter on 22 December. Beyond the Arctic of the sun and little realizes the earth ’s surface will be brought under the sun Circle the number of days with complete darkness that the earth on which he stands is constantly in at some time or other. A part of the earth’s surface increases, until we reach the North Pole (90°N.) motion. When the sun when half the year will have darkness. In the summer isappears, he says that the sun sets and when it that emerges from darkness into the sun’s rays emerges, e says that the sun rises. experiences sunrise. Later, when it is gradually ( June) conditions are exactly reversed. Daylight He is not the increases as we go polewards. At the Arctic Circle, -> : f. j * east aware that the sun , in fact, does not rise or set, obscured from the sun’s beams it experiences sunset. - 11 we who nse and we The sun is, in fact , stationary and it is the earth which the sun never ‘sets’ at mid-summer (21 June) and who set’! The earth moves there is a complete 24-hour period of continuous rotates. The illusion is exactly the same as when we " have height & m tW d staict axk fC W£St °t 0 CaSt * ways : it rotates on its own nce in every 24 hours< causing travel in a fast - moving train. The trees and houses daylight. In summer the region north of the Arctic dav n ni / l. 11 a so° Circle is popularly referred to as ‘ Land of the Mid¬.. ^.’ ^ revolves round the sun in an around us appear to move and we feel that the train is stationary. Fig. 7 explains the earth’s night Sun. At the North Pole, there will be six aUit ^ Vr ”& PiC :r^ fr0m and the" ?urin 365 ‘ dayS Causing the seasonS > rotation and the causes of day and night. months of continuous daylight. Fig. 8(a) illustrates curved edge of the earth convincing and the m » 'S 1S Orth’s sphericity ^ ^ Sh W clear|y the the most UP t0 date P f of the ' * ° Day and Night Sntf ; The Earth's Revolution ^ hen the earth revolves round the sun , it spins on an elliptical orbit at a speed of 18.5 miles per second the revolution of the earth and its inclination to the plane of the ecliptic which cause the variation in the length of day and night at different times of the year. 4 Google it:- www.UPSCPDF.com 5 https://t.me/UPSC_PDF meaning ‘equal , www.UPSCPDF.com https://t.me/UPSC_PDF days are termed because on these equinoxes two days all parts of the and nights. After the iu ° n r ; (I , the sun whilst it is still below the horizon. Since the sun rises and sets in a vertical path at the equator lines have been drawn on the globe. One set running east and west , parallel to the equator, are called lines have equal days tically overhead at the ^- s to move north and js Ver the period during which refracte equinox the sun appearTropic d light is received of Cancer (23t°xj 0, is short. But in temperate latitudes, the sun rises of latitude. The other set runs north and passing through the poles and are called lines of south about 21 June. This is known as the June or Slul ere wiliu ^ 1 and sets in an oblique path and the period of refracted