O Level Pakistan Studies (2059)
Climate
6 questions · about 5% of the marks we indexed · examined in 6 of 9 sessions.
Practice questions
Original questions written by HomiLabs in the style of the exam, with answers and mark schemes. They are not
Cambridge past paper questions and have not been reviewed by Cambridge. Try each one before opening the answer.
Q1Climate extremes and hazards · Core · Paper 2 style · 6 marks- (a) What is meant by the term drought? [2]
- (b) Explain two effects of drought on people living in the Thar Desert. You should develop your answer. [4]
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- (a) A long period with much less rainfall than normal, so that there is a serious shortage of water.
B1 long period / prolonged; B1 below-normal rainfall / water shortage.
- (b) Wells and ponds dry up, so women and children walk long distances for water, which may be unsafe to drink and spreads disease; grazing and fodder fail, so cattle, goats and sheep die and families lose their main source of food and income; food shortages lead to malnutrition, especially among children; many families migrate to barrage areas or towns to find work.
1 mark for each point and 1 mark for its development, for two points. Points: water shortage; livestock deaths; crop failure and hunger / malnutrition; disease; migration; debt.
- (a) Describe the causes of the severe floods in Pakistan in 2022. [3]
- (b) Explain two impacts of floods such as those of 2022 on farming in Pakistan. You should develop your answer. [4]
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- (a) Monsoon rainfall from June to August was several times the normal amount in Sindh and Balochistan; very high temperatures earlier in the year increased glacier melt in the north; much of the lower Indus plain is very flat, so water could not drain away; embankments were breached and hill torrents flooded towns.
1 mark per point up to 3: exceptional monsoon rain (Sindh, Balochistan); heatwave / glacier melt; flat land, poor drainage; breaches / hill torrents; deforestation or climate change accepted with explanation.
- (b) Standing crops such as cotton, rice and dates were destroyed, so farmers lost income and the country lost export earnings; livestock drowned, removing a source of milk and income; floodwater stood for months, so wheat could not be sown on time for the next rabi season; irrigation canals and roads were damaged, increasing costs.
1 mark for each point and 1 mark for its development, for two points. Points: crop losses; livestock deaths; delayed sowing; damaged canals / roads; food prices rise; soil damage or silt.
- (a) Name the hot, dry, dusty wind that blows across the plains of Punjab and Sindh in May and June. [1]
- (b) Describe two effects of dust storms and hot winds on people in the plains. [2]
- (c) Suggest two ways in which people in the plains adapt their daily lives to very hot summers. [2]
Show answer
- (a) The loo.
B1.
- (b) Heatstroke and dehydration, especially among outdoor workers; breathing problems and eye infections from dust; damage to crops and fruit; poor visibility disrupts road and air transport; power lines brought down.
1 mark each for two effects.
- (c) Working outdoors early in the morning or evening and resting at midday; thick-walled houses with small windows and flat roofs for sleeping on at night; drinking more water and traditional drinks; planting shade trees.
1 mark each for two adaptations.
Daily maximum temperatures (°C) during a heatwave in a coastal city:Day 1: 41, Day 2: 43, Day 3: 44, Day 4: 42, Day 5: 39, Day 6: 38, Day 7: 40
- (a) State the number of days on which the maximum temperature was 40 °C or above. [1]
- (b) Calculate the mean daily maximum temperature for the seven days. Give your answer to one decimal place. [2]
- (c) Explain two reasons why heatwaves cause more deaths in large cities such as Karachi than in rural areas. You should develop your answer. [4]
Show answer
- (a) 5 days
B1 5.
- (b) 287 ÷ 7 = 41.0 °C
M1 sum 287; A1 41.0 °C.
- (c) Concrete buildings and roads absorb heat by day and release it at night, so cities stay hot at night (urban heat island) and people get no relief; power cuts during peak demand stop fans and air-conditioners; many poor people live in crowded, poorly ventilated housing; outdoor workers such as labourers and street vendors cannot avoid the heat; water shortages make dehydration worse.
1 mark for each point and 1 mark for its development, for two points. Points: urban heat island; power and water shortages; crowded housing; outdoor workers; humidity at coast; lack of shade / trees.
- (a) State the two periods of the year when tropical cyclones are most likely to affect Pakistan's coast. [2]
- (b) Name two coastal areas of Pakistan that are at risk from tropical cyclones. [1]
- (c) Explain two ways in which authorities can reduce the impact of a tropical cyclone on coastal communities. You should develop your answer. [4]
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- (a) May–June (before the monsoon) and October–November (after the monsoon).
B1 each.
- (b) Any two: Karachi; Thatta / Keti Bandar (Indus delta); Badin; the Makran coast (Gwadar, Pasni, Ormara).
B1 for two.
- (c) Early warning systems using satellite tracking by the Meteorological Department give time to evacuate people from low-lying villages to shelters; fishermen can be told not to go to sea, so boats and lives are not lost; planting and protecting mangrove forests in the Indus delta absorbs storm surges and waves; building raised shelters and stronger houses reduces damage.
1 mark for each point and 1 mark for its development, for two points. Points: forecasting and early warning; evacuation and shelters; fishing ban; mangroves; embankments / building codes.
- (a) What is a glacial lake outburst flood (GLOF)? [2]
- (b) Explain why the risk of GLOFs is increasing in Gilgit-Baltistan and Chitral. You should develop your answer. [4]
Show answer
- (a) A sudden flood caused when water stored in a lake formed by a melting glacier breaks through the ice or moraine (rock debris) that dams it.
B1 lake formed by glacier melt; B1 sudden release when dam of ice/moraine fails.
- (b) Rising temperatures are making glaciers melt faster, so more and larger glacial lakes are forming; these lakes are held back by loose moraine or ice, which can give way suddenly; heavy rain or heatwaves can raise lake levels quickly; more people now live and build in narrow valleys below the glaciers, so more are exposed.
1 mark for each point and 1 mark for its development, for two points. Points: global warming / faster melting; more lakes forming; weak moraine dams; heatwaves and heavy rain; settlement in valleys.
River levels (m above normal) at a gauge on the Chenab during a monsoon flood:Day 1: 3.2, Day 2: 3.9, Day 3: 4.6, Day 4: 5.1, Day 5: 4.8, Day 6: 4.1, Day 7: 3.5
- (a) The danger level at the gauge is 4.5 m. State the number of days on which the river was above the danger level. [1]
- (b) Calculate the rise in river level from Day 1 to the peak. [1]
- (c) Explain two methods used in Pakistan to reduce the damage caused by river floods. You should develop your answer. [4]
Show answer
- (a) 3 days (Days 3, 4 and 5)
B1 3.
- (b) 5.1 − 3.2 = 1.9 m
B1 1.9 m.
- (c) Embankments (bunds) along the Indus and its tributaries keep high water within the river channel, protecting farmland and towns; large dams such as Tarbela and Mangla store monsoon floodwater and release it slowly; flood forecasting and early warnings from gauges and satellites give people time to move to safety; spurs and diversion channels protect barrages and cities.
1 mark for each point and 1 mark for its development, for two points. Points: embankments / bunds; dams and reservoirs; forecasting and warning; diversion channels; banning building on floodplains; afforestation upstream.
Air quality index (AQI) readings at one monitoring station in Lahore on six days in November:180, 245, 310, 420, 390, 260
- (a) State the number of readings that were above 300 ('hazardous'). [1]
- (b) Explain why smog is worst in Lahore between November and January. You should develop your answer. [4]
- (c) 'Smog in Lahore can only be reduced by controlling crop burning.' Evaluate this view. [6]
Show answer
- (a) 3
B1 3.
- (b) In winter cold, calm air near the ground is trapped under a layer of warmer air (temperature inversion), so pollutants cannot rise and spread; winds are light, so smoke builds up; at this time farmers burn rice straw after the harvest and smoke drifts over the city; emissions from vehicles, brick kilns and factories add to the pollution, and fog mixes with the smoke.
1 mark for each point and 1 mark for its development, for two points. Points: temperature inversion; calm winds; crop residue burning; vehicles, kilns, industry; fog.
- (c) For: crop residue burning in Punjab after the rice harvest produces large amounts of smoke exactly when smog peaks; offering farmers machines such as happy seeders or buying straw could cut this quickly. Against: vehicles are a major year-round source, so better fuel, emission checks and public transport (e.g. Lahore Metro Bus and Orange Line) are needed; brick kilns can switch to zig-zag technology; factories and burning of rubbish also contribute; planting trees and banning open burning in the city help. Judgement: e.g. controlling crop burning is important but not enough on its own, because traffic and industry pollute every day.
Level marking. L1 (1–2): simple points. L2 (3–4): developed point(s) for one view, or simple points for both. L3 (5–6): developed points for both views, a named Pakistani example and a judgement.
- (a) Pakistan produces less than 1% of the world's greenhouse gas emissions but is one of the countries most affected by climate change. Explain two reasons why Pakistan is very vulnerable to climate change. You should develop your answer. [4]
- (b) 'Pakistan should spend more on adapting to climate change than on reducing its own emissions.' Evaluate this view. [6]
Show answer
- (a) Its rivers depend on glaciers in the Himalaya, Karakoram and Hindu Kush, so faster melting first raises flood and GLOF risk and later threatens water supply; most of the country is arid or semi-arid with high temperatures, so heatwaves and droughts become more extreme; farming, which employs a large share of the workforce, depends on irrigation and monsoon rain; many people are poor and live in flood-prone areas, so they cannot easily recover.
1 mark for each point and 1 mark for its development, for two points. Points: glacier dependence; heat and aridity; agriculture-dependent economy; flood-prone plains / coast; poverty and weak infrastructure.
- (b) For adaptation: Pakistan's emissions are small, so cutting them will hardly change world temperatures; its people are already suffering floods, heatwaves and droughts, so money for flood defences, early warning, heat action plans, drought-resistant crops and water storage saves lives now. For reducing emissions: cleaner energy such as solar, wind and hydel reduces costly oil imports and air pollution (smog); reforestation such as large tree-planting programmes both stores carbon and reduces floods and soil erosion; showing action helps Pakistan gain international climate finance. Judgement: e.g. adaptation should come first, but many actions (solar power, trees) do both.
Level marking. L1 (1–2): simple points. L2 (3–4): developed point(s) for one view, or simple points for both. L3 (5–6): developed points for both views, a named Pakistani example and a judgement.
Rainfall (mm) at a station in Sindh in a flood year compared with normal:July: normal 60, flood year 210August: normal 70, flood year 330September: normal 40, flood year 150
- (a) Calculate the total rainfall for the three months in the flood year as a percentage of the normal total. Give your answer to the nearest whole number. [2]
- (b) Calculate the rainfall in August of the flood year as a percentage of normal. Give your answer to the nearest whole number. [1]
- (c) Explain why floods in the lower Indus plain of Sindh often last much longer than floods in the mountain valleys. You should develop your answer. [4]
Show answer
- (a) 690 ÷ 170 × 100 = 406%
M1 690/170; A1 406%.
- (b) 330 ÷ 70 × 100 = 471%
B1 471%.
- (c) The lower Indus plain is very flat with a gentle gradient, so water spreads out and drains away slowly; embankments, roads and canal banks trap water on the land side, so it cannot return to the river; the soil is fine and often already saturated, so little water soaks in; in the mountains steep slopes carry water away quickly although floods there are more sudden and destructive.
1 mark for each point and 1 mark for its development, for two points. Points: flat land / low gradient; obstructions (embankments, roads, canals); saturated or clay soils; high water table; contrast with steep mountain valleys.
Climate data for a lowland station in northern Punjab (rounded figures):Mean temperature (°C): Jan 13, Feb 16, Mar 22, Apr 28, May 33, Jun 35, Jul 32, Aug 31, Sep 30, Oct 26, Nov 20, Dec 15Rainfall (mm): Jan 22, Feb 26, Mar 24, Apr 15, May 12, Jun 30, Jul 160, Aug 150, Sep 60, Oct 10, Nov 4, Dec 12
- (a(i)) Name the hottest month. [1]
- (a(ii)) Calculate the annual range of temperature. [1]
- (b) Calculate the total annual rainfall. [2]
- (c) Explain two reasons why most of the rain at this station falls in July and August. You should develop your answer. [4]
Show answer
- (a(i)) June (35 °C)
B1 June.
- (a(ii)) 35 − 13 = 22 °C
B1 22 °C.
- (b) 525 mm
M1 adding the twelve months; A1 525 mm.
- (c) Moist monsoon winds from the Bay of Bengal, arriving from the east and south-east, reach northern Punjab in July, bringing humid air that rises and gives heavy showers; intense summer heating causes air to rise by convection, so it cools and condenses into thunderstorms; nearness to the foothills forces the moist air to rise (relief rain).
1 mark for each point and 1 mark for its development, for two points. Points: arrival of monsoon winds (moist air from the sea); convectional uplift from summer heating; relief uplift by nearby hills; low pressure over the heated land draws in moist air.
Climate data for a highland valley station at about 1,700 m in northern Balochistan (rounded figures):Mean temperature (°C): Jan 4, Feb 6, Mar 11, Apr 16, May 21, Jun 25, Jul 27, Aug 25, Sep 20, Oct 14, Nov 9, Dec 5Precipitation (mm): Jan 50, Feb 52, Mar 40, Apr 22, May 6, Jun 2, Jul 10, Aug 8, Sep 2, Oct 3, Nov 8, Dec 28
- (a) Calculate the annual range of temperature. [1]
- (b) State how many months have a mean temperature below 10 °C. [1]
- (c) Calculate the percentage of the annual precipitation that falls from December to March. Give your answer to one decimal place. [2]
- (d) Explain why this station receives most of its precipitation in winter rather than in the monsoon season. You should develop your answer. [4]
Show answer
- (a) 23 °C
B1 27 − 4 = 23 °C.
- (b) 4 months (Nov, Dec, Jan, Feb)
B1 4.
- (c) 170 ÷ 231 × 100 = 73.6%
M1 (28+50+52+40) = 170 mm out of 231 mm; A1 73.6%.
- (d) In winter, western depressions from the Mediterranean move east over Iran and Afghanistan and bring rain and snow to the north-western highlands; the monsoon winds come from the east and south-east and have lost most of their moisture before they reach Balochistan, and the mountains to the east block them, so summer is dry.
1 mark for each point and 1 mark for its development, for two points. Points: western depressions in winter (origin, path); snowfall at altitude; monsoon weak / exhausted by the time it reaches the west; rain shadow of ranges to the east; distance from the Bay of Bengal.
- (a) Name the four seasons of Pakistan's climate and give the approximate months of each. [4]
- (b) Describe the weather of the northern plains during the cold season. [3]
Show answer
- (a) Cold season – about mid-November to February; hot season – March to May/June; monsoon (rainy) season – about late June/July to September; post-monsoon (retreating monsoon) season – October to mid-November.
1 mark per season with roughly correct months.
- (b) Mainly dry, sunny days with cool to mild temperatures (about 10–20 °C by day); cold nights, sometimes with frost; dense fog in the plains, especially December–January; some light rain from western depressions.
1 mark per point up to 3.
Mean monthly temperatures (°C) for two stations in southern Pakistan (rounded figures). Station A is on the Arabian Sea coast; Station B is about 450 km inland in upper Sindh.Station A: Jan 19, Feb 20, Mar 24, Apr 28, May 30, Jun 31, Jul 30, Aug 29, Sep 29, Oct 28, Nov 24, Dec 20Station B: Jan 15, Feb 18, Mar 25, Apr 31, May 36, Jun 38, Jul 35, Aug 33, Sep 32, Oct 28, Nov 22, Dec 16
- (a) Calculate the annual temperature range for Station A and for Station B. [2]
- (b) Calculate how much hotter Station B is than Station A in June. [1]
- (c) Explain two reasons why Station A has a smaller temperature range than Station B. You should develop your answer. [4]
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- (a) A: 12 °C; B: 23 °C
B1 A 31−19 = 12; B1 B 38−15 = 23.
- (b) 7 °C
B1 38 − 31 = 7 °C.
- (c) Station A is on the coast, and the sea heats up and cools down more slowly than land, so it keeps the coast cooler in summer and warmer in winter; the daily sea breeze brings cooler, moist air on land in summer afternoons; Station B is far inland, where dry land heats strongly under clear skies in summer and loses heat quickly in winter nights (continentality).
1 mark for each point and 1 mark for its development, for two points. Points: maritime influence – sea heats/cools slowly; sea breezes; higher humidity / cloud at coast reduces extremes; continental interior – dry air, clear skies, rapid heating and cooling.
Monthly rainfall (mm) at a station at the foot of the Margalla Hills (rounded figures):Rainfall: Jan 55, Feb 70, Mar 75, Apr 50, May 35, Jun 70, Jul 300, Aug 290, Sep 110, Oct 30, Nov 15, Dec 35
- (a) Calculate the total annual rainfall. [1]
- (b) Calculate the percentage of the annual rainfall that falls in July, August and September. Give your answer to one decimal place. [2]
- (c) This station has a second, smaller rainfall peak. State the months in which it occurs and the weather system that causes it. [2]
- (d) Describe one way in which the timing of rainfall at this station helps farmers. [1]
Show answer
- (a) 1135 mm
B1 1135 mm.
- (b) 700 ÷ 1135 × 100 = 61.7%
M1 300+290+110 = 700; A1 61.7%.
- (c) February–March; western depressions (winter disturbances from the west).
B1 Feb–Mar; B1 western depressions.
- (d) Winter rain falls when rabi crops such as wheat are growing, so less irrigation is needed (or monsoon rain waters kharif crops).
B1 any valid link of rainfall season to crop season.
Mean monthly temperatures (°C) for a station in the central Punjab plain (rounded figures):Temperature: Jan 10, Feb 13, Mar 18, Apr 24, May 30, Jun 33, Jul 32, Aug 31, Sep 29, Oct 24, Nov 17, Dec 13
- (a) Calculate the mean annual temperature. Give your answer to one decimal place. [2]
- (b) State the number of months in which the mean temperature is 30 °C or more. [1]
- (c) Describe the pattern of temperature through the year. [3]
Show answer
- (a) 274 ÷ 12 = 22.8 °C
M1 sum = 274; A1 22.8 °C.
- (b) 4 months (May to August)
B1 4.
- (c) Cool winter with the lowest mean in January (10 °C); temperatures rise steadily from February to a maximum in June (33 °C); they stay high (31–32 °C) in July and August, then fall from September to December; annual range 23 °C.
1 mark per point up to 3; at least one figure needed for full marks.
Mean April temperatures at four places along a valley in the northern mountains (rounded figures):500 m: 22 °C1500 m: 15 °C2500 m: 9 °C3500 m: 2 °C
- (a) Using the data, describe the relationship between altitude and temperature. [2]
- (b) Calculate the average fall in temperature per 1,000 m between 500 m and 3500 m. Give your answer to one decimal place. [2]
- (c) Explain two ways in which the climate of the northern mountains affects the people who live there. You should develop your answer. [4]
Show answer
- (a) Temperature falls as altitude rises; it drops by about 6–7 °C for every 1,000 m (from 22 °C at 500 m to 2 °C at 3500 m).
B1 inverse relationship; B1 use of data / rate.
- (b) (22 − 2) ÷ 3 = 6.7 °C per 1,000 m
M1 20 ÷ 3; A1 6.7.
- (c) Heavy snow in winter blocks passes and roads such as the Karakoram Highway, so villages are cut off and supplies must be stored; the short growing season allows only one crop a year, so farming is limited; many people practise transhumance, moving livestock to high pastures in summer and down in winter; cold winters raise fuel use, leading to cutting of trees for firewood.
1 mark for each point and 1 mark for its development, for two points. Points: snow blocks transport; short growing season; transhumance / seasonal migration; demand for firewood / deforestation; tourism in summer.
Data for three stations in Pakistan (rounded figures):Station X: January mean −2 °C, July mean 17 °C, annual precipitation 650 mm, mostly falling as snow and rain in winter and springStation Y: January mean 18 °C, July mean 30 °C, annual rainfall 180 mmStation Z: January mean 14 °C, July mean 37 °C, annual rainfall 90 mm
- (a) Identify the climatic region of each station, choosing from: highland, lowland, coastal, arid. Use each region no more than once. Give one piece of evidence from the data for each. [4]
- (b) Suggest why Station Y receives less rain than many places further north in Pakistan, even though it is next to the sea. [2]
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- (a) X – highland (very cold winter, −2 °C in January, cool summer of 17 °C, much winter snow/precipitation); Y – coastal (small range of 12 °C, mild winter of 18 °C); Z – arid (very low total rainfall of 90 mm and very hot summer of 37 °C).
1 mark for each correct station with evidence (3); +1 for explaining that Z's very low rainfall makes it arid rather than lowland.
- (b) The monsoon winds reach this coast after crossing dry land / they blow parallel to the coast, and there are no mountains to force the air to rise, so little condensation happens; a temperature inversion over the coast stops air rising.
1 mark each for two points: no relief to lift air; winds parallel to coast / weakened monsoon; inversion layer / dry air above.
Climate data for a station in the Potwar Plateau (rounded figures):Mean temperature (°C): Jan 10, Feb 12, Mar 17, Apr 23, May 28, Jun 31, Jul 29, Aug 28, Sep 27, Oct 23, Nov 17, Dec 12Rainfall (mm): Jan 60, Feb 70, Mar 80, Apr 60, May 40, Jun 60, Jul 230, Aug 220, Sep 90, Oct 30, Nov 15, Dec 40
- (a) Using figures from the data, describe the climate of this station. [4]
- (b) Calculate the ratio of rainfall in the wettest month to rainfall in the driest month. Give your answer in the form n : 1, with n to one decimal place. [2]
- (c) Explain why June is hotter than July at this station although the sun is high in the sky in both months. [2]
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- (a) Hot summer, highest temperature in June (31 °C); cool winter, lowest in January (10 °C), range 21 °C; total rainfall 995 mm; wettest month July (230 mm) and August, so a clear monsoon maximum; driest month November (15 mm); a smaller winter–spring peak (70–80 mm in Feb–Mar).
1 mark per accurate point using data up to 4; must mention both temperature and rainfall for full marks.
- (b) 230 : 15 = 15.3 : 1
M1 230 ÷ 15; A1 15.3 : 1.
- (c) In July the monsoon brings thick cloud cover and rain, which reflect and block incoming sunshine and cool the ground by evaporation; June is mostly cloudless with dry air, so heating is stronger.
B1 cloud cover in July reduces insolation; B1 rain/evaporation cooling or clear skies in June.
- (a) What is meant by the term monsoon? [2]
- (b) State the direction from which the summer monsoon winds reach the northern Punjab. [1]
- (c) Explain two reasons why monsoon rainfall decreases from north-east to south-west across Pakistan. You should develop your answer. [4]
Show answer
- (a) A seasonal reversal of wind direction that brings a wet season; in Pakistan, moist winds from the sea in summer (July–September) bring most of the year's rain.
B1 seasonal change of wind direction; B1 brings heavy rain in summer / wet season.
- (b) From the east / south-east (from the Bay of Bengal).
B1.
- (c) The monsoon winds come from the Bay of Bengal across India, so they lose moisture as rain on the way and are driest when they reach the south-west; the north-east has the Himalayan foothills, which force air to rise and give heavy relief rain, while Sindh and Balochistan are low and flat or in rain shadow; the south-west is furthest from the source of moist air.
1 mark for each point and 1 mark for its development, for two points. Points: distance from Bay of Bengal / moisture lost on the way; relief rain in the north-east foothills; flat lowland / rain shadow in the south-west; Arabian Sea branch blows parallel to the coast.
- (a) Put these stages of the formation of convectional rain in the correct order:P Water vapour condenses into towering cumulonimbus cloudsQ The sun heats the ground stronglyR Heavy showers and thunderstorms fall in the afternoonS Warm air rises and cools [2]
- (b) Explain why convectional rain is most common in the plains of Punjab in the summer afternoons. You should develop your answer. [4]
Show answer
- (a) Q, S, P, R
B2 all correct; B1 if two adjacent stages are swapped.
- (b) In summer the sun is high and days are long, so the ground heats most strongly by the afternoon, causing warm air to rise rapidly; during the monsoon the air is humid, so rising air quickly reaches dew point and produces cumulonimbus clouds and thunderstorms; in winter heating is weaker and air drier, so convection rarely produces rain.
1 mark for each point and 1 mark for its development, for two points. Points: maximum heating in summer afternoons; humid monsoon air; rapid rising and cooling; contrast with winter.
Approximate mean annual rainfall at five places, from north-east to south-west (rounded figures):Murree: 1700 mmIslamabad: 1150 mmLahore: 650 mmMultan: 190 mmJacobabad: 110 mm
- (a) Calculate the difference in annual rainfall between the wettest and driest places in the table. [1]
- (b) Calculate the percentage decrease in annual rainfall from Murree to Jacobabad. Give your answer to one decimal place. [2]
- (c) Murree and Islamabad are about 40 km apart. Explain why Murree receives much more rain. [2]
Show answer
- (a) 1700 − 110 = 1590 mm
B1 1590 mm.
- (b) 1590 ÷ 1700 × 100 = 93.5%
M1 1590/1700 × 100; A1 93.5%.
- (c) Murree is about 2,000 m up in the hills, so moist monsoon air is forced to rise over the hills, cools and condenses, giving heavy relief rain; Islamabad is lower, at the foot of the hills.
B1 altitude / hills; B1 forced uplift → cooling → condensation (relief rain).
- (a) Describe western depressions, including where they come from and when they affect Pakistan. [3]
- (b) Explain two ways in which winter rainfall from western depressions is important for farming in Pakistan. You should develop your answer. [4]
Show answer
- (a) They are low-pressure weather systems that form over the Mediterranean Sea region and move eastwards over Iran and Afghanistan; they reach Pakistan mainly from December to March; they bring rain to the north and west, and snow to the mountains.
1 mark each for: low-pressure systems; origin Mediterranean; move east over Iran/Afghanistan; season (winter, Dec–Mar); rain/snow in north and west. Max 3.
- (b) It falls while rabi crops such as wheat and gram are growing, so it reduces the need for canal or tubewell water, which saves costs; in barani (rain-fed) areas of the Potwar Plateau it is the main water for wheat, so a dry winter means a poor harvest; snowfall in the mountains melts in spring and summer, feeding the rivers and canals used for irrigation.
1 mark for each point and 1 mark for its development, for two points. Points: waters rabi crops (wheat); barani farming dependent on it; snow store feeds rivers; reduces irrigation cost / pumping.
- (a) Explain how relief rainfall forms over the Himalayan foothills during the monsoon. You should develop your answer. [4]
- (b) 'Monsoon rainfall brings more benefits than problems to Pakistan.' Evaluate this view. [6]
Show answer
- (a) Moist monsoon winds blow towards the foothills and are forced to rise over the high ground; as the air rises it expands and cools, and when it reaches its dew point the water vapour condenses to form clouds; the droplets grow and fall as heavy rain on the windward slopes, while the leeward side is drier (rain shadow).
1 mark for each point and 1 mark for its development, for two points. Points: moist air forced to rise by mountains; cools on rising; condensation at dew point / clouds form; rain on windward side; rain shadow on leeward side.
- (b) Benefits: monsoon rain fills reservoirs such as Tarbela and Mangla, used for irrigation and hydel power; it waters kharif crops such as rice, cotton and sugar cane; it recharges groundwater for tubewells; it cools temperatures after the hot season. Problems: heavy rain causes floods, as in 2010 and 2022, destroying crops, homes and roads; urban flooding in cities such as Karachi and Lahore; landslides in the northern areas; standing water spreads malaria and dengue; rainfall varies from year to year, so a weak monsoon causes drought. Judgement: e.g. the benefits outweigh the problems because farming and power depend on it, provided flood management improves.
Level marking. L1 (1–2): simple points. L2 (3–4): developed point(s) for one view, or simple points for both. L3 (5–6): developed points for both views, a named Pakistani example and a judgement. Use named examples (e.g. 2022 floods, Tarbela, kharif crops).
Annual rainfall (mm) at a rain-fed (barani) farming area for five years:Year 1: 512, Year 2: 680, Year 3: 395, Year 4: 840, Year 5: 448
- (a) Calculate the mean annual rainfall for the five years. [1]
- (b) Calculate by what percentage the wettest year was above the mean. Give your answer to one decimal place. [2]
- (c) Explain two problems that this variability of rainfall causes for farmers who depend on rain. You should develop your answer. [4]
Show answer
- (a) 2875 ÷ 5 = 575 mm
B1 575 mm.
- (b) (840 − 575) ÷ 575 × 100 = 46.1%
M1 difference ÷ mean × 100; A1 46.1%.
- (c) In dry years such as Year 3 crops fail and fodder is scarce, so farmers lose income and may have to sell animals or borrow money; in very wet years such as Year 4 floods and waterlogging damage crops and soil; farmers cannot plan which crops to sow or how much seed and fertiliser to buy, so they choose low-risk, low-yield crops.
1 mark for each point and 1 mark for its development, for two points. Points: drought years – crop failure, debt; wet years – flooding / soil erosion; uncertainty in planning; migration to cities in bad years.
- (a) A town at 250 m has a mean July temperature of 33 °C. Temperature falls by about 6.5 °C for every 1,000 m of height. Estimate the mean July temperature of a hill resort at 2250 m. [2]
- (b) Explain why temperature falls as altitude increases. [2]
- (c) Name two factors other than altitude that affect temperatures in Pakistan. [2]
Show answer
- (a) 33 − 6.5 × 2 = 20 °C
M1 height difference 2000 m → 6.5 × 2 = 13 °C; A1 20 °C.
- (b) The air is heated mainly from the ground, so air further from the ground is cooler; at higher altitudes the air is thinner (lower pressure), holds less heat and less water vapour, so it absorbs and keeps less heat.
B1 heating from the ground surface; B1 thinner air holds less heat.
- (c) Any two: latitude; distance from the sea; cloud cover; aspect (direction a slope faces); winds.
B1 each.
- (a) What is meant by the term latitude? [1]
- (b) Explain how cloud cover affects temperatures in Pakistan by day and by night. You should develop your answer. [4]
- (c) State one way in which the aspect of a slope affects temperature in the northern mountains. [1]
Show answer
- (a) The distance of a place north or south of the Equator, measured in degrees.
B1.
- (b) By day, cloud reflects and absorbs sunlight, so less reaches the ground and daytime temperatures are lower (e.g. during the monsoon); by night, cloud acts like a blanket and traps heat radiated from the ground, so nights are warmer; with clear skies in deserts days are very hot and nights cold, giving a large daily range.
1 mark for each point and 1 mark for its development, for two points. Points: day – reflects insolation, cooler; night – traps outgoing radiation, warmer; clear skies – large daily range in deserts; example monsoon / Thar.
- (c) South-facing slopes receive more direct sunshine, so they are warmer (snow melts earlier) than north-facing slopes.
B1.
- (a) Suggest why Jacobabad in upper Sindh is one of the hottest places in Pakistan in May and June. [3]
- (b) Explain why places in the far north of Pakistan are colder in winter than places in the far south. You should develop your answer. [4]
Show answer
- (a) It is far from the sea, so there is no cooling sea breeze (continentality); the sky is cloudless and the air very dry, so the sun heats the ground strongly; the sun is almost overhead and days are long in early summer; it is on a low flat plain surrounded by dry land and hot winds (loo) blow across it.
1 mark per point up to 3: distance from sea; clear skies / dry air; high sun angle and long days; low altitude; hot dry winds.
- (b) The north is at a higher latitude, so the winter sun is lower in the sky and its energy is spread over a larger area, and days are shorter, so less heating; most of the north is also at high altitude, where the air is thinner and holds less heat; cold air from Central Asia can reach it, while the south is moderated by the warm Arabian Sea.
1 mark for each point and 1 mark for its development, for two points. Points: latitude / angle of the sun; shorter winter days; altitude; distance from the warm sea; cold northerly air.
Mean temperatures for a coastal city and an inland city in Balochistan (rounded figures):Coastal city: coolest month 17 °C, hottest month 30 °CInland city at 1,600 m: coolest month 3 °C, hottest month 27 °C
- (a) Calculate the annual temperature range for each place. [2]
- (b) Explain how the sea breeze keeps coastal areas cooler on summer afternoons. You should develop your answer. [4]
Show answer
- (a) Coastal: 13 °C; inland: 24 °C
B1 30 − 17 = 13; B1 27 − 3 = 24.
- (b) By day the land heats up faster than the sea, so warm air rises over the land and creates lower pressure; cooler, denser air moves in from the higher pressure over the sea to replace it, lowering temperatures on the coast; the moist sea air also adds cloud and humidity, which limits further heating.
1 mark for each point and 1 mark for its development, for two points. Points: land heats faster than sea; low pressure over land; cool air flows in from the sea; moist air / cloud limits heating.
July mean temperatures at three stations in the same mountain district (rounded figures):Station P: altitude 150 m, July mean 34 °CStation Q: altitude 1350 m, July mean 27 °CStation R: altitude 2350 m, July mean 21 °C
- (a) Using a fall of 6.5 °C per 1,000 m, calculate the temperature expected at Q and at R from the temperature at P. [2]
- (b) Calculate the difference between the actual and the expected temperature at Q and at R. [2]
- (c) Suggest two factors, other than altitude, that could explain these differences. [2]
Show answer
- (a) Q: 34 − 6.5 × 1.2 = 26.2 °C; R: 34 − 6.5 × 2.2 = 19.7 °C
B1 Q 26.2; B1 R 19.7.
- (b) Q: 27 − 26.2 = +0.8 °C (actual warmer); R: 21 − 19.7 = +1.3 °C (actual warmer)
B1 Q 0.8; B1 R 1.3.
- (c) Aspect – the stations may be on south-facing slopes that receive more direct sunshine; sheltered valley sites trap heat; less cloud cover or less forest; local winds (e.g. warm dry winds descending into valleys).
B1 each for two valid factors with brief explanation.
