WAEC SSCE - Geography - 2004 (Essay)

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(a) What is an environmental hazard?

An environmental hazard is any natural or human-induced event or condition in the environment that poses a threat or danger to human life, property and other living things. It is a situation with the potential to cause damage, injury, loss or destruction.

(b) Five examples of environmental hazards

• Flooding.
• Drought and desertification.
• Earthquakes.
• Volcanic eruptions.
• Soil erosion (also acceptable: landslides, storms/hurricanes, oil spillage, deforestation, pollution).

(c) Three effects of environmental pollution

• Health problems: polluted air and water cause diseases such as cholera, respiratory illness and skin infections, and can lead to death.
• Destruction of ecosystems and living things: pollution kills fish, wildlife and plants, poisons the soil and reduces biodiversity.
• Damage to agriculture and economic loss: contaminated soil and water lower crop yields and fish catch, spoil water supplies and impose high clean-up and treatment costs; air pollution also contributes to global warming and acid rain.

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(a) Characteristic features of the Tropical Continental (Sudan/Savanna) Climate

• It lies roughly between latitudes 5° and 15° north and south of the Equator.
• Distinct double season: a wet season in the high-sun period and a long dry season in the low-sun period.
• Total annual rainfall is moderate, about 50 cm to 100 cm, decreasing towards the poles/desert margins.
• Rainfall is convectional and falls mainly in one maximum during the wet season.
• Temperatures are high all year, generally 21°C to 32°C, with the hottest period just before the rains.
• The annual temperature range is greater than in the equatorial zone (about 8°C or more).
• Relative humidity is low, especially in the dry season when the dry, dusty Harmattan wind blows.
• Skies are largely clear in the dry season, giving high sunshine and strong evaporation.

(b) Vegetation of the Savanna region

• It consists mainly of tall grasses interspersed with scattered trees, giving a parkland appearance.
• Grasses grow tall (up to 3-4 m) in the wet season and dry up, turning brown, in the dry season.
• Trees are deciduous and drought-resistant, shedding leaves in the dry season to reduce water loss.
• Trees have adaptations to drought and fire: thick, fire-resistant bark, long tap roots, small leathery leaves and umbrella-shaped crowns (e.g. baobab, acacia, shea, locust bean).
• Vegetation is zoned by rainfall: it changes from Guinea savanna (moist, taller trees) through Sudan savanna (shorter grass, fewer trees) to Sahel savanna (thorn scrub) as rainfall decreases polewards.
• Grasses are tufted, growing in tussocks rather than continuous turf.

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(a) Factors which may favour a rapid growth of population

Human factors:

1. High birth rate: Early marriage, polygamy and the desire for large families raise the number of births and speed up growth.
2. Improved medical facilities: Better health care, immunisation and drugs lower the death rate, especially infant mortality, so more people survive.
3. In-migration: The movement of people into an area for jobs, security or better living conditions adds to its population.

Physical factors:

1. Favourable climate: Moderate temperature and reliable rainfall support farming and comfortable living, attracting and retaining people.
2. Fertile soils: Rich soils give good harvests and food security, encouraging settlement and population increase.
3. Availability of water and mineral resources: Adequate water supply and the presence of minerals attract settlers and support economic activity that sustains a growing population.

(b) Problems that may arise from rapid population growth:

1. Food shortage: Population may outstrip food production, leading to hunger and malnutrition.
2. Unemployment: The labour force grows faster than available jobs, causing widespread unemployment and low incomes.
3. Pressure on social amenities: Housing, schools, hospitals, water and electricity become overstretched and inadequate.
4. Environmental problems: Overcrowding, poor sanitation, congestion and pollution increase, and land is degraded through overuse.

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(a)(i) Two areas of copper mining in Zambia: the Copperbelt Province towns of Kitwe, Chingola, Mufulira, Ndola and Luanshya, and the newer Solwezi (Lumwana/Kansanshi) area in the North-Western Province.

(a)(ii) One method of copper mining: Open-cast (open-pit) mining is used where the copper ore lies near the surface. The overburden (soil and rock covering the ore) is stripped off with heavy machinery, and the exposed ore is drilled, blasted and loaded onto trucks in a series of descending benches, then hauled to the surface for crushing, concentration and smelting. (Where the ore is deep, underground/shaft mining is used instead.)

(b) Contributions of copper mining to Zambia's economic development:

1. It is the chief source of foreign exchange, earning most of Zambia's export income.
2. It provides government revenue through taxes and royalties used for development.
3. It creates employment for miners, engineers and support workers.
4. It has stimulated growth of towns, railways and industries in the Copperbelt.

(c) Problems facing copper mining in Zambia:

1. Price fluctuations: Falling and unstable world copper prices reduce earnings.
2. Landlocked position: High transport costs to distant seaports raise export costs.
3. Depletion, deep ores and power/water shortages: Rising extraction costs, ore depletion and unreliable electricity hamper production.

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(a) Outline map of Nigeria showing mineral-producing areas and towns

Key to the map:

• Crude oil: Niger Delta, with Port Harcourt shown and named.
• Limestone: Ewekoro area, Ogun State, with Ewekoro shown and named.
• Columbite: Jos Plateau, with Jos shown and named.

(b) Five ways crude oil contributes to the economic development of Nigeria

1. Foreign exchange earnings: Export of crude oil earns foreign exchange for Nigeria.
2. Government revenue: Government obtains revenue from petroleum taxes, royalties, rents and export sales.
3. Employment: It provides direct and indirect employment in exploration, drilling, refining, transport, marketing and related services.
4. Industrial raw material and energy: Petroleum provides fuel for transport and industries and raw materials for petrochemical, fertiliser, plastic and allied industries.
5. Infrastructure and urban growth: Oil revenue finances roads, schools, hospitals, ports, pipelines and other public facilities, while oil activities encourage the growth of towns such as Port Harcourt and Warri.

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(a) Sketch map of West Africa

The sketch map below shows two ECOWAS coastal countries, two ECOWAS interior countries and the capitals of the four countries.

Key: Ghana and Nigeria are coastal ECOWAS countries. Mali and Burkina Faso are interior ECOWAS countries. The capitals shown are Accra, Abuja, Bamako and Ouagadougou.

(b) Problems facing ECOWAS

1. Poor transport and communication: Inadequate roads, railways, sea links and communication facilities make movement of people and goods between member states difficult.
2. Differences in currencies: The use of different national currencies makes trade and payment between member countries more difficult and costly.
3. Political instability: Coups d'état, civil unrest, wars and insecurity in some member states disrupt regional cooperation and development projects.

(c) Possible solutions

1. Member states should jointly improve roads, railways, ports, air transport and telecommunication links within West Africa.
2. ECOWAS should work towards the adoption of a common currency and harmonised monetary policies.
3. Member states should promote good governance, respect constitutional rule and cooperate in peacekeeping and conflict resolution.

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(a) Orographic (relief) rainfall

Orographic rainfall forms when moist air is forced to rise over a highland or mountain barrier. Warm, moisture-laden winds (often from the sea) meet a mountain range and are compelled to rise up the windward slope. As the air rises it cools at the lapse rate; on reaching its dew point the water vapour condenses to form clouds, and heavy rain falls on the windward slope. After crossing the summit, the air descends the leeward slope, warms and dries; this drier region is the rain shadow, which receives little rain.

(b) Convectional rainfall

Convectional rainfall forms through the strong heating of the ground surface. Intense insolation heats the land, which in turn heats the layer of air above it. This warm, moist air becomes lighter and rises rapidly in strong upward (convection) currents. As it rises it cools and condenses, building tall cumulonimbus clouds. When condensation is complete, heavy rain falls, usually in the afternoon and often with thunder and lightning. It is common in the equatorial regions and in the tropics during hot afternoons.

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(a) Outline map of Nigeria showing cash-crop producing areas and towns

Key: The labelled dots show towns: Akure, Enugu, Kano and Zaria. The shaded or labelled areas show the main producing zones for cocoa, palm produce, groundnut and cotton.

(b) Three major problems of agriculture in Nigeria

1. Inadequate capital and credit facilities: Many farmers cannot obtain sufficient money to buy land, machinery, fertiliser, improved seeds and other farm inputs.
2. Primitive farming methods: The use of hoes and cutlasses on small scattered holdings results in low output and makes mechanisation difficult.
3. Pests, diseases and adverse weather: Insect pests, crop diseases, livestock diseases, drought and floods destroy crops and animals.

(c) Solutions to the problems

1. Government, agricultural banks and co-operative societies should provide farmers with adequate, low-interest loans and subsidies for farm inputs.
2. Farmers should be encouraged to use tractors and other machines, improved seeds, fertilisers and extension services. Land reform and consolidation should also be carried out to reduce fragmentation of farm holdings.
3. Extension officers should educate farmers on the proper use of insecticides, fungicides and veterinary drugs. Irrigation, drainage and flood-control schemes should be developed to reduce dependence on unreliable rainfall.

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(a) Four effects of the revolution of the earth

• The four seasons: as the earth revolves round the sun with its axis tilted, the overhead sun shifts between the tropics, giving spring, summer, autumn and winter in temperate lands.
• Varying length of day and night: at different times of the year, days and nights become unequal in length (long days/short nights in summer and the reverse in winter), except at the equator.
• Changing altitude (apparent movement) of the midday sun: the noon sun is high overhead at some seasons and low at others.
• Occurrence of equinoxes and solstices, and the basis of the calendar year (365.25 days), leading to a leap year every fourth year.

(b) Time calculation

Match starts at 8:00 p.m. local time in Los Angeles (75°W). Find the time in Nigeria (15°E).

Difference in longitude \( = 75^\circ + 15^\circ = 90^\circ \).

\[ \text{Time difference} = \frac{90}{15} = 6 \text{ hours} \]

Nigeria lies east of Los Angeles, so its time is ahead; we add 6 hours:

\[ 8{:}00 \text{ p.m.} + 6 \text{ hours} = 2{:}00 \text{ a.m.} \]

Nigerian fans should switch on their televisions at 2:00 a.m. (the following day).

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(a) Calculation of the missing percentages

Percentage premium income = \(\dfrac{\text{premium income}}{\text{total premium income}}\times100\).

Motor:

\[\frac{94,442,000}{202,320,000}\times100=46.678\ldots\%\approx \boxed{46.7\%}\]

Miscellaneous:

\[\frac{20,040,000}{202,320,000}\times100=9.904\ldots\%\approx \boxed{9.9\%}\]

Type of insurance	Premium income (₦)	Percentage (%)
Fire	24,532,000	12.1
Accident	13,770,000	6.8
Motor	94,442,000	46.7
Marine	49,536,000	24.5
Miscellaneous	20,040,000	9.9
Total	202,320,000	100.0

Check: \(12.1+6.8+46.7+24.5+9.9=100.0\%\).

(b)(i) Percentage bar graph

The bar represents the whole premium income, that is, \(100\%\). Its sections show the percentage contribution of each class of non-life insurance.

(b)(ii) Disadvantages of a percentage bar graph

1. It shows the relative percentages only; the actual premium incomes in naira cannot be read directly from the graph.
2. Very small component parts are difficult to draw, measure and compare accurately.

(c) Alternative method

A pie chart (divided circle) can be used to represent the statistics.

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(a) (i) Annotated cross-profile from A to B

(ii) Points A and B are not intervisible. The intervening hills rise above the line of sight between A and B and therefore obstruct visibility.

(b) Effects of relief on transportation

1. The area is mainly upland; consequently, road construction is difficult and transport routes are few.
2. The rugged hills in the western and northern parts discourage the construction of roads and other transport lines.
3. The less rugged eastern and south-eastern part permits a secondary road, while footpaths are few and widely spaced in the high-relief areas.

(c) Reasons for sparse population

1. The western and northern parts are rugged, high and inaccessible; hence, there are few or no settlements there.
2. Farming is difficult on the high, steep and rugged land, so few people settle in the area.

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(a) Ways railway transport has contributed to economic development in Tropical Africa:

1. Movement of bulky goods: Railways carry heavy and bulky raw materials such as minerals (copper, coal, tin), timber and agricultural produce cheaply over long distances from the interior to the ports.
2. Opening up of the interior: Rail lines linked landlocked and remote inland regions to coastal ports, encouraging settlement, farming and mining in previously inaccessible areas.
3. Promotion of trade and commerce: By providing regular and relatively cheap transport, railways widened internal and export markets and stimulated buying and selling of goods.
4. Employment generation: Construction, operation and maintenance of railways provide jobs for engineers, drivers, clerks, labourers and traders, raising incomes.
5. Growth of towns and industries: Many towns (e.g. junction and terminal towns) grew along rail routes, and industries were sited near railways to obtain raw materials and distribute finished products.

(b) Ways of improving the development of railway transport in Tropical Africa:

1. Modernisation and expansion: Extend the rail network and construct new standard-gauge lines to link more producing regions, ports and neighbouring countries.
2. Re-equipment: Replace obsolete locomotives, coaches and worn-out tracks with modern engines and stronger rails to improve speed and reliability.
3. Adequate funding: Increase government investment and encourage private and foreign investment (public-private partnership) to finance construction and maintenance.
4. Regular maintenance: Establish workshops and train skilled personnel to service tracks, bridges and rolling stock regularly.
5. Gauge standardisation and inter-country links: Adopt a uniform gauge and connect national railways to promote through-traffic and regional integration.

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Describe the formation and appearance of any two of the following (two are treated here).

(i) Stack

Formation: a stack develops on a headland of fairly resistant rock. Waves attack lines of weakness at the base by hydraulic action and corrasion, first cutting a cave. When two caves on opposite sides of a narrow headland join, or a cave is cut right through, an arch is formed. Continued erosion and weathering widen the arch until its roof becomes too heavy and collapses, leaving an isolated pillar of rock standing in the sea. This is a stack.

Appearance: a tall, steep-sided, isolated column or pillar of rock rising out of the sea just off the coast, separated from the mainland cliff.

(ii) Blow hole

Formation: a blow hole forms where a sea cave is cut into a cliff along a line of weakness (a joint). Waves force water and compressed air up through the joint towards the top of the cliff. Continued hydraulic action enlarges the joint until it breaks through to the cliff top, forming a vertical shaft. During high tides or storms, water is forced up the shaft and spouts out at the surface.

Appearance: a roughly circular opening or hole on top of a cliff, connected below to a sea cave, through which spray and water spout upward with a blowing sound.

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(Country referred to: Nigeria.)

(a) Four factors that promote international trade

1. Differences in natural resources: Nigeria has crude oil, cocoa and solid minerals that other countries lack, while it needs machinery and manufactured goods produced abroad, creating a basis for exchange.
2. Differences in level of industrial/technological development: industrialised nations supply capital goods and technology that developing Nigeria cannot yet produce.
3. Availability of transport and communication links: shipping routes, ports, air links and modern communications make the movement of goods between countries possible.
4. Membership of international/economic organisations: membership of bodies such as ECOWAS, OPEC and the WTO removes barriers and encourages trade. (Others: surplus production for export, favourable government policy and a stable currency.)

(b) Three problems in trade with other West African countries

1. Similarity of products: most West African states export the same primary commodities (cocoa, palm produce, minerals), so they compete rather than complement one another.
2. Poor transport links between the countries: few good roads and railways connect the states, and rivers are interrupted by rapids, making the movement of goods difficult and costly.
3. Multiplicity of currencies and language/colonial barriers: different currencies, exchange controls and English/French divisions hinder smooth payment and dealing. (Also smuggling, trade restrictions and tariffs.)

(c) Three solutions

1. Diversify production so that member states produce different goods that can be exchanged instead of competing.
2. Improve inter-state transport by constructing trans-West African roads and railways and easing border crossings.
3. Adopt a single/common currency and harmonise trade policies (as pursued under ECOWAS) to simplify payments and remove tariff barriers.

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(a) Outline map of Nigeria showing the required transport features

The map includes two international airports: Murtala Muhammed International Airport at Lagos and Nnamdi Azikiwe International Airport at Abuja. It also shows the Lagos–Ibadan–Ilorin–Minna railway, the River Niger as a major inland waterway, Apapa as a seaport, and Onitsha as a river port.

(b) Four economic importance of road transport in Nigeria

1. Roads move people between homes, workplaces, schools, markets, towns and rural areas.
2. They transport agricultural produce, raw materials and manufactured goods, helping producers reach markets.
3. They promote domestic trade by linking places of production with places of consumption.
4. They provide employment for drivers, mechanics, road construction workers, fuel sellers and other transport-related workers.

(c) Two problems of road transportation in Nigeria

1. Poor road condition and inadequate maintenance: potholes, damaged bridges and poorly maintained roads slow journeys, damage vehicles and increase accidents.
2. High cost of road transport: expensive fuel, spare parts and vehicle maintenance raise the cost of moving passengers and goods.

Examination reminder: For a map question, use conventional symbols, place each feature in its approximate correct location, and label every symbol clearly with a ruler line where necessary.

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(a) Four components of soil

1. Mineral (inorganic) matter: weathered rock particles (sand, silt and clay) that form the bulk of the soil and supply nutrients such as potassium, calcium and phosphorus.
2. Organic matter (humus): decomposed remains of plants and animals which give the soil its dark colour, improve fertility and help retain moisture.
3. Soil water (moisture): water held in the pore spaces which dissolves nutrients and makes them available to plant roots.
4. Soil air: gases occupying the pore spaces, supplying oxygen for respiration of roots and soil organisms. (Living organisms such as bacteria, earthworms and fungi are also present.)

(b) The soil profile

A soil profile is a vertical section through the soil from the surface down to the parent rock, showing a succession of layers called horizons.

• O horizon (litter layer): topmost layer of fresh and decaying leaves and organic debris.
• A horizon (topsoil): dark, rich in humus and living organisms; the zone from which minerals are leached downward.
• B horizon (subsoil): lighter coloured zone of accumulation where clay, iron and minerals leached from above are deposited.
• C horizon: partly weathered, broken parent rock (regolith).
• D horizon (bedrock): the solid unweathered parent rock beneath.

See the labelled soil-profile diagram showing these horizons in order from the surface downward.

(c) Three farming practices that lead to soil erosion

1. Bush burning: burning of vegetation before cultivation removes the protective plant cover, exposing bare soil to rain-splash and wind.
2. Overgrazing: keeping too many animals strips the grass cover, loosens the topsoil and allows it to be washed or blown away.
3. Cultivation on steep slopes / ploughing up and down the slope: tilling along the direction of the slope creates channels that guide run-off, accelerating gully and sheet erosion. (Continuous cropping without fallow and shifting cultivation also expose and exhaust the soil.)

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(a) Sketch map of Africa showing two important lumbering areas

(b) Factors that promote lumbering in Africa

1. Availability of extensive forest reserves: Equatorial Africa and parts of West Africa have large stands of valuable hardwood trees such as mahogany, ebony and iroko.
2. Favourable hot and wet climate: High temperatures and heavy, reliable rainfall encourage rapid growth of dense tropical forests.
3. Fertile soils: In suitable forest areas, soils support the growth and regeneration of trees.
4. High demand for timber: Timber is needed locally and abroad for building, furniture, paper, plywood and other wood products.
5. Improved transport: Roads, railways, rivers and ports help to move logs from forest areas to sawmills, markets and exporting ports.
6. Establishment of sawmills and wood-processing industries: These provide facilities for converting logs into usable timber and wood products.

(c) Benefits of lumbering in Africa

1. It provides employment for tree fellers, machine operators, sawmill workers, transporters and traders.
2. It earns foreign exchange through the export of logs, sawn timber, plywood and other forest products.
3. It provides revenue to governments through taxes, licences, royalties and export duties.
4. It supplies raw materials for furniture, paper, plywood, carving and other industries.
5. It provides timber for building and construction works.