ICSE Solutions

ICSE Solutions for Class 7 Geography Voyage – Greenhouse Effect and Global Warming

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APlusTopper.com provides step by step solutions for ICSE Solutions for Class 7 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 7 with Free PDF download option. Geography Voyage for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

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DISCUSS

Collect rainfall data from the website of Indian Meteorological Department (IMD) for Mumbai, Chennai, Delhi and Kolkata and discuss how rainfall patterns have changed in the last 5 years.
Answer:

Mumbai receives maximum rainfall in 2016 and minimum rainfall in 2012.
Chennai receives maximum rainfall in 2013 and minimum rainfall in 2012.
Delhi receives maximum rainfall in 2013 and minimum rainfall in 2014.
Kolkata receives maximum rainfall in 2013 and minimum rainfall in 2014.

VALUES AND LIFE SKILLS :

We need to understand that global warming, climate change, acid rain and ozone depletion are all happening because of our dependence on fossil fuels and CFC-based technologies. Therefore, the need of the hour is to reduce
our dependence on them.
What can you do in this regard ?
Answer:
The ways to reduce our dependency on them are :

1. By using materials such as bamboo, recycled metal and organic paints in construction of buildings.
2. By using solar energy to heat and light homes and offices.
3. By using clean fuel like CNG and unleaded petrol to run vehicles.
4. By making changes in everyday practices such as
   (a) choosing to travel in public vehicles, biking, walking or using a car pool.
   (b) buying energy efficient household appliances.
   (c) replacing light bulbs with CFL bulbs.

EXERCISES

A. Fill in the blanks.

1. Carbon dioxide and methane, nitrous oxide, water vapour and CFCs are examples of greenhouse gases.
2. Global Warming is a major cause of climate change.
3. The increase in earth’s temperature is called global warming.
4. The layer of atmosphere where ozone is found is called stratosphere.
5. The ozone layer protects us from the ultraviolet rays of the sun.

B. Write True or False.

1. Aeroplanes flying in the sky cause global warming.
Answer. True.

2. Forest fires do not cause global warming.
Answer. False.
Correct : Forest fires do cause global warming.

3. Ozone is found in the troposphere.
Answer. False.
Correct : Ozone is found in the stratosphere.

4. The ozone layer is harmful for humans and animals.
Answer. False.
Correct : The ozone layer is not harmful for humans and animals.

5. CFCs and BFCs protect the ozone layer.
Answer. False.
Correct : CFCs and BFCs deplete the ozone layer.

C. Choose the correct option.

Question 1.
Oxygen/Carbon dioxide is a greenhouse gas.
Answer:
Carbon dioxide is a greenhouse gas.

Question 2.
Use of fossil fuels/hydroelectricity causes global warming.
Answer:
Use of fossil fuels causes global warming.

Question 3.
Cattle release methane / CFCs.
Answer:
Cattle release methane.

Question 4.
Global warming will reduce/increase climate change.
Answer:
Global warming will increase climate change.

Question 5.
The ozone layer is found between 20 and 40/40 and 60 km above the earth’s surface.
Answer:
The ozone layer is found between 20 and 40 and above the earth’s surface.

D. Match the following

Answer:

E. Answer the following questions in brief 

Question 1.
Why do we call carbon dioxide a greenhouse gas?
Answer:
Carbon dioxide is called greenhouse gas because it absorbs
Infrared radiations. A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range.

Question 2.
Name two more greenhouse gases.
Answer:
Methane and water vapour are other greenhouse gases.

Question 3.
How will countries like Bangladesh and Thailand be affected by global warming?
Answer:
Climate change will cause melting of polar ice caps with huge chunks of icebergs several kilometres across breaking off from the mainland. This is already taking place around the Arctic and in Antarctica. The result will be an increase in the volume of ocean waters. Countries like Bangladesh, Thailand and Malaysia and the Southeastern parts of USA like the States of Florida and Louisiana would be swamped by flood water along its shores.

Question 4.
What is responsible for causing a hole in the ozone layer?
Answer:
The release of large amount of CFCs or chlorofluorocarbons and BFCs or bromofluorocarbons by industries are responsible for the formation of holes in the ozone layer.

Question 5.
Name some diseases that are caused due to exposure to ultraviolet rays of the sun.
Answer:
Exposure to UV rays can cause sunburn, cataract, hair loss, skin cancer and birth deformities.

F. Answer the following questions in one or two paragraphs 

Question 1.
How is the greenhouse effect created?
Answer:
The ‘greenhouse effect’ takes place when the ‘sun’s rays heat the earth. This heat is absorbed by the surface of the earth and some of it is radiated back into the atmosphere. However, a part of this heat is trapped in the atmosphere by gases such as water vapour, carbon dioxide and methane while the rest escapes into space. These gases let in light from the sun but prevent the heat from escaping like the glass walls of a greenhouse. They also act like a mirror and reflect back to the earth some of the trapped heat energy. The more greenhouse gases (GHGs) are present in the atmosphere, the more heat is trapped, subsequently making the earth warmer.

Question 2.
State three causes that have led to an increase in greenhouse gases in the atmosphere.
Answer:
The causes that have led to the increase in greenhouse gases (GHGs) are:

1. Increase in industries
2. Increase in deforestation
3. Increase in atmospheric pollution due to emissions from chimneys of factories
4. Increase in natural disasters like floods, volcanic eruptions and earthquakes that release large amounts of smoke, dust and gases into the atmosphere
5. Increase in the methane content of the atmosphere because of large-scale cattle rearing, since cattle release methane
6. Expansion of cies and towns

Question 3.
What do you understand by the term ‘global warming’?
Answer:
The greenhouse gases in the atmosphere trap a part of the heat radiated back by the earth, increasing its temperature. The increase in the earth’s temperature is called global warming.

Question 4.
State some anthropogenic (man-made) causes of global warming.
Answer:
Man-made causes of global warming ‘include burning of fossil fuels, cutting of forests, using refrigerators, air conditioners, aerosols, factories belching smoke, increase in methane content of the atmosphere because of large-scale cattle rearing, expansion of cities and towns.

Question 5.
Global warming does not augur well for our planet earth. State at least three reasons to support this statement.
Answer:
Global warming is not good for our planet as

(a) It will worsen climate changes leading to food shortages.
(b) Many forms of wildlife are now’ at risk and since climate change and deforestation are causing disappearance of their habitat.
(c) Climate change will cause melting of polar caps resulting in the increase in the volume of ocean waters.

G. Picture study.

Question 1.
Which region of the world is seen in the picture?
Answer:
Antarctica and Arctic Poles.

Question 2.
How is it going to be affected by global warming?
Answer:
Global warming causes melting of polar ice-caps with huge chunks of icebergs several kilometres across breaking off from the mainland resulting in increase in volume of ocean waters. The increase in the volume of ocean waters will result in rising of sea levels. Countries like Bangladesh, Thailand and Malaysia and the Southeastern parts of USA like the States of Florida and Louisiana would be swamped by flood water along their shores.

LETS DO SOMETHING

Question 1.
Imagine that you are an active member of the Greenpeace. Write a two-page appeal addressed to the Prime Minister of India stating why you think that increasing number of vehicles on roads will be disastrous to the nation in the long run.
Answer:
August 25, 2017,
Mr. Narendra Modi,
Prime Minister of India
Dear Prime Minister Modi,

It is with great optimism and hope that we are following news about the meeting you will have with U.S. President Trump, at this critical time in our planet’s future. 2017 is the year for making decisive commitments towards tackling climate change together. As the elected leader of the world’s largest democracy, and a country with much to lose from run away climate change, the hopes of 1.3 billion Indian citizens rest on you. Along with them, and the millions of people worldwide who will inevitably be affected by decisions made this year, we hope you will successfully push the United States, and the developed world, towards an ambitious and equitable global agreement to rein in climate change.

We congratulate you on setting new and ambitious renewable energy targets, and urge a focus on decentralized renewable energy as the fastest, most cost-effective way to tackle India’s energy poverty challenge. At the same time, we believe that continued growth in coal power is not in the interests of common Indians as it imposes a significantly higher cost on people’s health, livelihood of communities and the environment, and will prove far more expensive than renewable energy. We hope you will secure much-needed support from global partners, civil society and investors – including the United States administration – to realize these renewable energy goals.

Being the member of the Greenpeace, I would like to bring in your kind notice that I found that the number of vehicles has increased considerably in India in the past five years, which is one of the sources of pollution. In the recently released World Health Organization (WHO) report on pollution, the situation of the city is not so encouraging in terms of pollution in the air.
Due to increase in number of vehicles over the years, the city roads witness frequent traffic congestions, but above all, the vehicles emitting pollutants are affecting environment badly. The recently-released WHO report shows that India has 2.5 microns of diameter (PM2.5) concentration of 68 micrograms particulate matter per meter cube. However, the WHO guideline values for particulate matter is 10 microgram per meter cube for PM2.5.

“The air pollution consists of many pollutants, among other particulate matter. These particles are able to penetrate deeply into the respiratory tract and therefore constitute a risk for health by increasing mortality from respiratory infections and diseases, lung cancer, and selected cardiovascular diseases,” says the WHO report.

New patients with respiratory problems are constantly being reported in hospitals. Recently, the many big cities are witnessing a flow of traffic on city roads consisting high end cars too. Moreover, as far as public transport is concerned, the government-owned low floor buses could be seen plying on the road emitting black smoke causing problems for pedestrians, bikers and other roadside vendors. Mr. Avinash Chowdhry senior member of Greenpeace took out a rally of school children at Statue

Circle (Mumbai) on the eve of World Environment Day said, “Men’s health is determined by his environment. He is greatest enemy of his own health. Environmental pollution is one of the reasons of cardiovascular diseases, hypertension and diabetes.”
Collaboration between the government and civil society is essential to secure a bright future for India and the planet. Greenpeace looks forward to working with the Indian government on our common objective of ensuring clean, affordable renewable energy for all.

Sincerely,
VeenuGopal,
Interim Executive Director, Greenpeace

Question 2.
Make a collage using pictures or a chart to show the various causes and consequences of global warming.
Answer:
You can take idea from the picture given below and can make a collage of your own.

ICSE Solutions for Class 8 Geography Voyage – Asia: Climate and Natural Vegetation

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ICSE Solutions Class 8 GeographyHistory & CivicsBiologyChemistryPhysicsMaths

Exercises

A. Fill in the blanks

1. A few regions of South-west Asia receive winter rainfall from the temperate cyclones that originate over the Mediterranean Sea. (tropical cyclones, temperate cyclones, north-east winds, south-east winds)
2. The Mediterranean climate is ideally suited growing citrus fruits, (equatorial, warm temperate east coast, Mediterranean, tropical monsoon).
3. The tropical rain forests of Asia are dense and impenetrable, (steppes, mangrove forests, monsoon forests, tropical rain forests)
4. About one-third of the land area of Asia is covered with forest.
5.  Thermal electricity is produced by burning coal and petroleum.

B. Match the following

Answer:

C. Answer the following questions in brief

Question 1.
When does most of Asia receive maximum rainfall ? Give a reason for your answer.
Answer:
Most of the Asia receives maximum rainfall in the months of April, May and June. In summers, most of Asia has an average temperature of about 32°C. The hot air over the land rises and creates an area of low pressure. There is high pressure in the surrounding seas and oceans. So there is movement of warm moisture-laden onshore winds which are called monsoons. These winds cause heavy rainfall.

Question 2.
Name any two countries that experience Mediterranean climate.
Answer:
Syria, Turkey, Lebanon and Israel experience Mediterranean climate.

Question 3.
Explain how the climate of the cold temperate regions of Asia has affected the :

1. Vegetation
2. Wildlife

Answer:

1. Vegetation of the cold temperate regions of Asia — These regions experience long severe winters with heavy snowfall and very short, cool summers with light rainfall. So the natural vegetation has adapted very well to the climate. The evergreen softwood trees of the region are conical in shape and have needle-like leaves. They are called coniferous trees as they have cones in which they bear their seeds. The common tree species are pine, fir, spruce, larch and cedar. The forests are also called as taiga.
2. Wildlife — Several small to medium sized animals such as the fox, sable, bear, mink, lynx and squirrel are found here which have fur over their bodies to protect them from cold weather.

Question 4.
Name some wildlife species found in the taiga region, the tundra region, and the tropical deciduous forests of Asia..
Answer:
Wildlife species found in the taiga region are fox, sable, bear, mink, lynx and squirrel. Wildlife species found in the tundra region of Asia are polar bears, reindeer, foxes, seals and walruses.
Wildlife species found in the tropical deciduous forests of Asia are rhinoceros, elephants, bears, deer, apes, lions, tigers, leopards, etc.

Question 5.
Trees cannot grow of survive in the regions beyond the Arctic Circle in Asia. Why ?
Answer:
Trees or forests cannot grow or survive in the regions beyond the Arctic Circle in Asia because this region has long severe winters and the frozen subsoil which do not permit the growth of trees and this region is, therefore, devoid of forests.

D. Answer the following questions in one or two paragraphs

Question 1.
Identify the main factors that affect the climate of Asia. Explain any two of them.
Answer:
The Main factors that affect the climate of Asia are :

1. Size and latitudinal extent — Asia is the largest continent with a large east-west extent. Also, it stretches across the torrid, temperate and frigid heat zones of the earth.
2. Distance from the sea — Many parts of Asia are far away from the maritime influence of the seas and oceans and experience extreme conditions and continental climate. Places closer to the’Coasts enjoy equable or maritime climate.
3. Relief features — like mountain ranges of Asia extend in the east-west direction and form barriers to the moisture laden winds and the cold winds.
4. Wind — Moisture bearing winds from the south and cold winds of the north affect the climate of the places.
5. Ocean Currents — The cold Oya Siwo and the warm Kuro Siwo ocean currents affect the temperatures of the coastal regions of Japan.

Question 2.
Describe the climatic conditions in Asia from October to March.
Answer:
From October to March, Asia experiences winter season as the northern hemisphere receives the slanting rays of the sun because of the tilt of the earth’s axis. The temperature falls to 0°C and even below freezing point in many parts of the northern Asia. The air over the land is cold and heavy and sinks causing high pressure. The surrounding oceans and seas ! have higher temperature and lower pressure so the cold air
moves from land (high pressure) to sea (low pressure). These winds are dry and hence most of the Asia receives no winter rainfall except South-East Asia, Japan, South-Eastern India i and parts of Sri Lanka, where the same winds cross the seas
and pick up moisture. A few regions of South-West Asia receive winter rainfall from the temperate cyclones that originate over the Mediterranean Sea.

Question 3.
Write about the Mediterranean climate experienced in Asia.
Answer:
The Mediterranean Climate in Asia is characterized by warm, dry summers and cool, wet winters.
Since these areas experience drought-like conditions in summer, the natural vegetation has adapted to the climate by developing long roots and spongy barks. The evergreen vegetation of oak, acacia, laurel, chestnut, walnut and olive trees is common. Orchards of citrus fruits such as lemons, and oranges, vineyards and farm grains have replaced the natural vegetation. In the absence of natural habitat, not much wildlife is found. Mostly domesticated animals such as donkeys, cattle and sheep are found.

Question 4.
Describe each of these forests :

1. Tropical deciduous
2. Equatorial rainforest.

Answer:

1. Tropical deciduous forests — They are found in tropical monsoon climate. These areas have hot wet summers with heavy rainfall and cool dry winters. Tropical deciduous forests are also called as monsoon forests. They have hardwood, broad-leaved trees which shed their leaves, in the dry season, usually in winter. Teak, Sal, shisham and mango are the common tree species. These thrive in regions of heavy rainfall. Grasses and thorny bushes grow in drier regions. Elephants, rhinoceros, bear, deer, apes, lion tiger, leopard, etc are some of the wildlife species found here.
Such forests are found in India, Pakistan, Bangladesh, Thailand, Myanmar, Vietnam, Laos, Cambodia and Southern China.

2. Equatorial rainforest — Such forests are found in equatorial climate where the temperatures are high of about 28-30°C and rainfall occurs all year round. Such climatic conditions have resulted in dense, hardwood forests with broad-leaved tree species such as mahogany, ebony, rosewood, cinchona, coconut and rubber. There are lianas, creepers and climbers, tall grass, ferns and bamboos that grow between the tall trees, which makes the forests dense and impenetrable. The forests are dark and gloomy as very little sunlight reaches the ground owing to the tall trees whose branches spread out, forming a canopy. Mostly arboreal or tree-dwelling animals such as monkey, apes and colourful birds are found. Reptiles such as lizards, snakes, crocodiles and insects are found in the swampy floors of the forests. Large animals such as elephants and wild cats are only found in the outskirts as the forest interior is too dense.
Such forests are found in countries located close to the equator like Malaysia, Indonesia, and Southern Philippines.

Question 5.
How has modernization changed the natural vegetation of the Mediterranean and steppe regions ?
Answer:

• Mediterranean region — Due to modernization, most of the natural vegetation has been replaced by grain farms, orchards of citrus fruits such as lemons and oranges and vineyards.
• Steppes region (Temperate Grassland) —Vast areas of grasslands have been converted into rich farmlands that grow wheat, barley and other food grains.

Question 6.
How are forests useful to the people of Asia?
Answer:
About one-third of the land area of Asia is covered with forest. Some of these forests provide hardwood, bamboo, sandalwood and camphor. They also provide other valuable forest products such as lac, resin, turpentine, honey, medicinal plants and herbs. Natural rubber is obtained from the latex of the rubber tree. The evergreen rainforest of the equatorial region and the monsoon forests of the tropical regions of Asia are the chief sources of these products.
Softwood forests yield softwood for making paper, pulp, newsprint, matchsticks and synthetic fibers such as rayon. These are obtained from trees such as birch, pine, cedar and fir, which grow in the taiga or coniferous forests region of northern Asia, especially Siberia.

Question 7.
Give an account of the mineral resources of Asia.
Answer:
Asia has vast deposits of different types of minerals such as iron ore (India, Malaysia, China, Russia, Japan, the Philippines, North Korea), coal (China, India, Kazakhstan, Russia), bauxite (India, Indonesia, Russia), and petroleum (Saudi Arabia, United Arab Emirates, Bahrain, Kuwait, Iran, Iraq, Malaysia, Indonesia, China, Russia).

E. Map study
On an outline map of Asia, mark the following:

• area affected by the monsoons
• regions of equatorial climate
• regions of Mediterranean climate
• areas under the steppes

Answer:
(a) Area affected by the monsoons

F. Picture study

Question 1.
Identify the animal seen in the photograph.
Answer:
Yak

Question 2.
In which climatic region of Asia can you find this animal ?
Answer:
Temperate or mid-latitude Desert region of Asia.

Extra Questions

Question 1.
Write a short note on summer conditions in Asia.
Answer:
From April to June, the sun rays fall directly over the northern hemisphere. In June, it shines overhead the Tropic of Cancer, so most of the continent of Asia, except the extreme northern parts beyond the Arctic Circle is warm with an average temperature of 32°C. Most of the Asia receives maximum rainfall in these months.

Question 2.
Why is Siberia so sparsely populated ?
Answer:
Siberia is sparsely populated as the climate here is very cold. Winters are long and severe with heavy snowfall which the summers are short and cool.

Question 3.
Write a short note on the tropical or hot desert climate and the natural vegetation and wildlife found there.
Answer:
Tropical or hot desert climate prevails in Arabia, Iran and the Thar desert in India and Pakistan. These regions experience very hot dry summers and very cold winters. The daily and annual ranges of temperature are very high and the areas receive less than 25 cm of rainfall annually.
As climatic conditions are harsh, vegetation is scarce and only thorny bushes, shrubs, cacti and clumps of dry grasses are found scattered in the region which is largely bare and devoid of vegetation. Date palms are found in the oases. Camels, horses, mules, gazelles, insects and lizards are some of the wildlife species found in the deserts.

Question 4.
What type of climate do China, Japan and Korea experience?
Answer:
China, Japan and Korea experiences warm temperate eastern margin or China type climate. It is similar to monsoon type except that the winters are colder. Snowfall occurs in winters while rainfall occurs in summer.

Question 5.
Which is the most common domesticated animal in Tibet ? What kind of climate is found in the Plateau of Tibet and the Gobi Desert ?
Answer:
Yak is the most common domesticated animal in Tibet. Temperate (or mid-latitude) desert climate is found in the Plateau of Tibet and the Gobi Desert. Very little rainfall, very cold winters with temperatures below the freezing point and very hot summers is found.

Question 6.
What increases the commercial value of forests in cool temperature eastern margin climate ?
Answer:
Oak, beech, maple and birch are the main trees and their occurrence in almost pure stands and predominance of only a handful of species greatly increase the commercial value of these forests.

Question 7.
List the major types of climate of Asia.
Answer:
The major types of climate of Asia are :

1. Equatorial climate
2. Tropical monsoon climate.
3. Tropical or hot desert climate. .
4. Warm temperate eastern margin or China type climate.
5. Temperate or mid-latitude desert climate.
6. Mediterranean climate
7. Cool temperate eastern margin climate
8. Temperate grassland or steppe climate
9. Cold temperate or taiga climate
10. Arctic or tundra climate.

Question 8.
What are the different types of vegetation found in varied climatic conditions of Asia ?
Answer:
The different types of vegetation in Asian climate include dense evergreen hardwood forests, tropical deciduous forest, thorny bushes, coarse short grasses, evergreen softwood trees and mosses and lichens.

9. Fill in the blanks.

1. The areas away from the coasts experience continental (extreme), climate while places closer to the coasts experience maritime (equable) climate.
2. World’s highest surface temperature of 71°C has been recorded in Dasht-eLut in Iran.
3. Mawsynram in Meghalaya receives the heaviest rainfall in the world.
4. Verkhoyansk in Russia is the coldest region in Asia with an average temperature of-51 °C. ’
5. Most of the Asia receives no rainfall in winter.
6. Convectional rainfall occurs almost daily around 4 o’ clock in equatorial climate region of Asia.
7. Latex is the milky sap of rubber tree which is collected and used to make rubber for commercial purposes.
8. The equatorial (tropical) rainforests are different from the rainforests of the Amazon and Zaire basins because of their nearness to the sea.
9. India has tropical monsoon climate and tropical deciduous (monsoon) forests.
10. Date palms are found in the Oases in hot deserts.
11. The Gobi Desert stretches across large parts of Mongolia and China.
12. Yak is one of the most commonly domesticated animals in the temperature desert regions of Asia.
13. The two-humped Bactrian camel is a well-known animal of temperate grassland or steppe.
14. The temperate grassland region of Central Asia is called steppe.
15. The forests of the cold temperate regions, have coniferous trees with needle like leaves.
16. The coniferous forests in cold temperate climate are called as Taiga.
17. The treeless plains in the Arctic climate are called Tundra.

Map Skills
On a physical map of Asia, show the different types of climate and natural vegetation
Answer:

ICSE Solutions for Class 7 Geography Voyage – Africa: Location, Area, Political & Physical Features

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 7 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 7 with Free PDF download option. Geography Voyage for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 7 Geography History & CivicsMathsPhysicsChemistryBiology

THINK AND ANSWER

Why did Africa remain unexplored for a long time ?
Answer:
The equator passes through the middle of the continent and most of Africa lies within the tropics. It is, therefore, the hottest continent.
People faced many difficulties while exploring Africa. In the north, the Sahara, the world’s largest desert, was impenetrable due to severe heat and dry conditions. Most of Africa consists of undulating plateaus, so it was difficult to reach the interior from the coastal areas. The rivers of Africa have many rapids and waterfalls, and are not fit for navigation. The extensive equatorial forests and swampy lands teeming with dangerous tsetse flies and poisonous insects discouraged explorers from entering the heart of the continent.

Discuss

Deforestation rate in Africa is twice the average for the rest of the world with more than four million hectares of primary forest disappearing every year. What could be the reasons for this.
Answer:
The reasons would be :

1. Conversion of forests for subsistenance and commercial agriculture.
2. Deforestation done because of commercial logging
3. Other activities such as cattle rattling, cash crop plantations, and the construction of dams, roads and mines.

VALUES AND LIFE SKILLS

The Sahara Desert forms a large part of Africa. This desert extends from the Atlantic in the west to the Red Sea in the east.
Suppose you were going to the Sahara Desert. List the things you would take with you.
What kind of problems are you likely to face ?
How would you cope with them ?
Answer:
The things one should carry and the problems we can face are discussed below :
1. Preparing for Desert Emergencies —
(a) Wear clothing that minimizes sweat loss : Most of your body’s water loss happens through perspiration. Cover as much skin as possible with loose, light-weight clothing. This will trap the sweat against your skin, slowing evaporation and therefore water loss.
(b) Bring lots of extra water : Whenever you enter a desert, bring more water than you expect. While walking in sunshine and 40°C (104°F) heat, the average person loses 900 mL (30 oz) of sweat every hour. In an emergency situation, you’ll be thankful for any water you carried.

1. Divide the water you’ re carrying among several containers. This minimizes the amount of water you can lose to one leak.
2. Store the excess in a cool spot in your vehicle, away from direct sunlight.

(c) Bring food that packs the most nutrition in the least size and weight: Energy bars, pemmican, jerky, and trail mix are popular choices. Do your research, experiment beforehand, and be prepared. When wheeled vehicles break down, it’s just your two legs and the path to the next town, and you don’t want to be carrying anything nonessential.
(d) Pack survival equipment: Here are the bare essentials for a survival kit:

1. Sturdy emergency blankets
2. Cords or rope
3. Water purification tablets
4. First aid kit
5. Fire starters
6. Powerful flashlight or headlamp. LEDs last longest.
7. Knife
8. Compass
9. Signal mirror
10. Goggles and a dust mask or bandana (for dust storms)

2. Survival Tactics :
(a) Become nocturnal: In a desert survival situation, you do not want to be moving around during the day. The cooler night air enables you to travel farther and faster with minimum danger of heat exhaustion. In hot climates, this single decision will save your body about three liters (three quarts) of water per day.
(b) Stay in a shelter during the day: If you don’t have a shaded car to stay in, string cords between a pair of objects in a place that gets shade most of the day. Drape a sturdy emergency blanket over the cords. Place a few pieces of brush on top of the blanket, then cover it with another emergency blanket (this one can be a thin Mylar sheet). The gap of air between the two blankets insulates the shelter, keeping it cooler.
(c) Signal for help : Building a fire is a great way to make a signal, creating smoke during the day and light at night. While in transit, keep a signal mirror in reach to reflect light at passing aircraft or distant cars.
(d) Decide whether to stay in place : If you have a supply of water and someone knows where you are, staying in one place may be your best chance of rescue. Traveling to find help will exhaust you much faster than staying in place, and water loss will cut your survival time way down if you can’t find another supply. That said, if your water supplies are low, you will need to look for more. You cannot expect to survive more than a couple of days if you run out of water.
(e) Find water sources : If there’s been a rainstorm recently, you may find pockets of water in rock outcrops or flat stone surfaces. More often, you’ll need to search for areas with possible groundwater:

1. Follow animal tracks leading downhill, birds circling around something, or even flying insects.
2. Walk to the greenest vegetation you can see, especially large plants with wide leaves.

3. Recognizing Dangers
(a) Watch out for signs of dehydration : Many people make their journey much harder by underestimating their water needs. Trying to ration your supply is a mistake that can cost your life. If you notice any of the following symptoms, drink more water:

1. Urine with a dark color or a noticeable smell.
2. Dry skin
3. Dizziness
4. Fainting

(b) Rest if you experience heat exhaustion : If you feel lightheaded or nauseous, or if your skin feels cool and clammy, seek shade immediately. Rest and treat yourself as follows:

1. Remove or loosen your clothing
2. Sip a sports drink or slightly salty water (about 5 mL salt per liter water /1 tsp per quart).
3. Apply wet cloth on your skin to aid cooling evaporation.

(c) Stay away from dangerous animals : Most mammals and reptiles will stay away from you, especially if they are alone. Follow the same practice and be aware of your surroundings to avoid accidentally cornering something.

EXERCISES

A. Choose the correct answer :

1. The strait that separates Europe from Africa is the

1. Palk Srait
2. Bering Strait
3. Strait of Gibraltar
4. trait of Magellan

2. A large portion of Africa lies in the

1. desert
2. tropics
3. temperate region
4. marshy land

3. The area in a desert where water can be found is called a/an

1. pond
2. well
3. depression
4. oasis

4. The Sudd is a

1. lake
2. swamp
3. gulf
4. cape

5. The largest lake in Africa is

1. Lake Chad
2. Lake Tana
3. Lake Victoria
4. Lake Tanganyika

B. Identify who I am

1. i am a country through which the Tropic of Capricorn passes: Namibia.
2. I am the southernmost tip of Africa: Cape of Good Hope.
3. I am a snow-capped mountain near the equator: Mt. Kilimanjaro.
4. I am the longest river of Africa: Nile.
5. I am a river that flows into Lake Chad: The Chari.
6. I am a lake that does not lie in the Great Rift Valley of Africa: Lake Victoria.
7. I am a river that flows through the Namib Desert: Okavango

C. Match the following:

Answer:

D. Give geographical reasons

Question 1.
People faced many difficulties while exploring Africa.
Answer:
It was difficult to explore Africa because of deserts like Sahara which have severe heat and dry conditions, the undulating plateaux, non-navigable rivers, extensive equatorial forests, swampy lands and poisonous insects.

Question 2.
The rivers of Africa are not very suitable for navigation in their lower course.
Answer:
The rivers have many rapids and waterfalls making them unfit for navigation.

Question 3.
The river Nile flows through a desert and yet has water throughout the year.
Answer:
River Nile has water throughout the year because its source is Lake Victoria which lies in the rainy equatorial region.

E. Answer the following questions briefly.

Question 1.
Give the latitudinal extent of Africa and explain why it is mostly a tropical continent.
Answer:
Latitudinal extent of Africa is 37°N to 35°S. Africa is known as mostly tropical continent because a large portion of Africa lies in the Tropics, the Tropic of cancer (23 1/2° N) in the North and the Tropic of Capricorn (23 1/2° S) in the South.

Question 2.
Name three great explorers connected with the African continent.
Answer:
David Livingstone, who discovered Victoria Falls in 1855. Mungo Park followed the course of the river Niger. Henry Morton Stanley traced the course of the river Congo from Lake Tanganyika to its mouth.

Question 3.
Name the major mountain ranges of Africa.
Answer:
The Atlas Mountains lie in north-western Africa. They are young fold mountains consisting of three parallel ranges—the Tell Atlas in the north, the High Atlas in the middle, and the Sahara Atlas in the south. The highest peak in the Atlas Mountains is Mt Toublkal, which remains snow-capped most of the year.

Question 4.
Name the lakes found in the Great Rift Valley.
Answer:
The lakes found in the Great Rift Valley are Lake Malawi, Lake Mobutu, Lake Edward and Lake Turkana.

Question 5.
How much time does it take the cocoa tree to yield cocoa pods ?
Answer:
An evergreen tropical plant, the cocoa tree grows to a height of 4 to 9 m. It begins to yield cocoa pods after about 5-7 years. Cocoa pods grow on the trunk and main branches. Each pod is about 18-25 cm long and contains pulp with beans.

F. Answer the following questions in one or two paragraphs

Question 1.
Elaborate on the achievements of the great explorers in opening up the continent of Africa.
Answer:
Explorers like David Livingstone discovered Victoria Falls. Mungo Park discovered the course of river Niger. Henry Morton Stanley traced the source of river Congo from Lake Tanganyika to its mouth.

Question 2.
Name the major physical divisions of Africa. Describe any one.
Answer:
Africa can be divided into the following physical divisions: the Atlas Mountains, the low central plateau, the high plateau of the south, the Great Rift Valley, the Nile and Congo-Zaire Basins, and the coastal plains.

1. The Atlas Mountains lie in north-western Africa. They are young fold mountains.
2. There are three parallel ranges – the Tell Atlas in the north, the High Atlas in the middle, and the Sahara Atlas in the south. The highest peak in the Atlas Mountains is Mt Toubkal, which remains snow-capped most of the year.
3. The low central plateau extends from the Atlantic Coast in the west to the Nile Valley in the east. The Sahara Desert forms a part of this plateau. This desert extends from the Atlantic in the west to the Red Sea in the east, and covers an area of 8.6 million sq.km.
4. The Great Rift Valley of Africa is a special physical feature of the southern plateau. It is a long narrow valley formed as a
   result of vertical cracks that developed because of the movements within the earth. It extends for a total distance of 5,000 km from Lake Malawi to the Red Sea and the Gulf of Aqaba to the Dead Sea in Jordan.

Question 3.
Describe the three important deserts found in Africa.
Answer:
The three important deserts are Sahara, The Namib, The Kalahari.
Sahara is part of the low Central Plateau. It is the largest desert in the world covering the area of 8.6 million square km.
The Namib, desert runs along the Western Coast in South-West Africa.
Kalahari desert lies in the Southern part of Africa forming part of High Plateau of South Africa.

Question 4.
What is a rift valley? How is it formed?
Answer:
The Great Rift Valley is a long narrow valley formed as a result of vertical cracks that developed because of movements within the earth. It extends for a total distance of5,000 km from Lake Malawi to Red Sea and the Gulf of Aqaba to Dead Sea in Jordan. Many freshwater lakes, such as Malawi, Tanganyika, and Turkana are found here.

Question 5.
Give an account of the major lakes of Africa.
Answer:
Lake Victoria is the largest lake of Africa. The river Chari flows into Lake Chad. Lake Tanganyika is one of the longest freshwater lake in the world. Other large lakes in Great Rift Valley are Malawi, Mobutu, Edward and Turkana.

G. Map work:
On a blank outline map of Africa, mark the following:

1. The Cape of Good Hope
2. The Drakensberg Mountains
3. The Victoria Falls
4. The Atlas Mountains
5. The Nile River
6. The Libyan Desert
7. The Suez Canal

Answer:

H. Picture Study

This is a photograph of Victoria Falls.
Question 1.
Name the explorer who discovered it.
Answer:
David Livingstone discovered Victoria Falls in 1855.

Question 2.
On which river is this fall located ?
Answer:
Victoria Fall is located on Zambezi River.

LET’S DO SOMETHING

On a blank outline map of Africa

(a) Mark with brown lines the Atlas and the Drakensberg Mountains.
(b) Shade with yellow and label the Sahara Desert and the Kalahari Desert.
(c) Shade with light brown the plateau region of Africa, the Ethiopian and Adamawa Highlands.
(d) Colour with blue and label neatly all the surrounding water bodies, oceans, seas, bays, gulfs, and straits.

Answer:
Do it Yourself.