Elements of Physical Geography

For Junior Secondary School (Form One)

Revised Edition

NWANA Martin Tabufor &

AMA WA Sani Gur

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PART ONE:

TABLE OF CONTENTS

GENERAL PHYSICAL GEOGRAPHY

CHAPTER 1: THE SOLAR SYSTEM IN THE UNIVERSE 9 The universe 9 The sun and the solar system 9 The moon, its phases and eclipses 12 Tools for space exploration 13 Review exercises 15

CHAPTER 2: THE EARTH IN SPACE 1 7 Shape and size 17 Locating places; longitudes and latitudes 18 The movements of the earth; rotation, revolution and effects 19 Review exercises 26

CHAPTER 3: LANDMASSES AND WATER BODIES OF THE EARTH 2 8

The earth's interior 28 The splitting and drifting of continents 29 Types of water bodies and landmasses 29 Distribution of oceans and continents 31 Review exercises 32

CHAPTER 4: MAJOR LANDFORMS OR RELIEF OF THE CONTINENTS 33

Definition of landforms; minor and major landforms 33 Major landforms 33 Origin of landforms; their description 37 Review exercises 41

CHAPTER 5: MAJOR LANDFORMS OF THE OCEANS AND -SALINITY OF WATER 44

Submarine landforms of the continental margins 44 Submarine landforms of the deep ocean floor 45 Salinity of water 4 7 Review exercises 48

CHAPTER 6: THE ATMOSPHERE, WEATHER AND CLIMATIC ELEMENTS 50

Definition and structure of the atmosphere 50 Meaning of weather and climate 51 Elements of weather and instruments at a weather measuring station 51 Importance of weather and climate 54 Review exercises 55

CHAPTER 7: FACTORS OF TEMPERATURE 57 Sunshine or insolation and temperatures 57 Types of temperature measurements 57 Factors influencing temperature 58 Global warming 63 Review exercises 64

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CHAPTER 8: PRESSURE AND WINDS 66 Meaning of air pressure 66 Factors determining pressure 66 The distribution of pressure on the earth surface 68 Winds and its link with pressure 69 Planetary and local winds 70 Review exercises 7 4

CHAPTER 9: MOISTURE IN THE ATMOSPHERE 76 Definition of moisture 76 Evaporation and condensation 76 Effects of condensation 77 Cloud formation and types 78 Precipitation forms 79 Types of rainfall 80 The water cycle and rivers 82 Review exercises 83

CHAPTER 10: NATURAL VEGETATION AND SOILS 86 Nature of natural vegetation 86 Different forms of plants 86 Classes of vegetation 87 Soils and layers or horizons 88 Soil texture 89 Review exercises 90

PART TWO: PHYSICAL GEOGRAPHY OF CAMEROON 92 Situation, size and shape of Cameroon 92

CHAPTER 11: RELIEF AND DRAINAGE OF CAMEROON 93 Major highlands 93 Major lowlands 94 Drainage basins 95 Lakes 97 Review exercises 98

CHAPTER 12: CLIMATE, VEGETATION AND SOILS 100 General characteristics of climate 100 Types of climate 100 Vegetation . 102 Soils 104 Review exercises 105

GLOSSARY 108

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