2025 OCR GCSE Geography A (Geographical Themes) - J383 模擬試題連答案詳解

Waves exploit a crack by hydraulic action and abrasion to form a cave. The cave erodes through the headland to form an arch. When the arch roof collapses, the isolated column of rock left standing in the sea is a stack.

1 mark for B (Stack). Do not credit more than one letter. A is the earlier stage; C is a depositional landform; D is a wide indentation of the coast.

Counter-urbanisation is the movement of people from large urban areas to smaller settlements and rural areas beyond the city edge. Re-urbanisation is the return of people to inner city areas, and suburbanisation is growth at the city's edge within the urban area.

1 mark for C (Counter-urbanisation). Do not credit more than one letter. A describes movement back into the city centre; B describes outward growth to the edge of the built-up area; D describes the physical spread of the built-up area, not a migration trend.

Natural gas is a fossil fuel formed over millions of years and cannot be replaced within a human timescale, so it is non-renewable. Wind, tidal and solar power are renewable because they are naturally replenished.

1 mark for C (Natural gas). Do not credit more than one letter. A, B and D are all renewable sources.

Find offshore wind in the data table (28%). On the y-axis, 25 and 30 are labelled gridlines, so 28 lies three fifths of the way from 25 to 30. Draw a bar of the same width as the others up to this height.

1 mark: bar plotted at 28% (accept 27.5 to 28.5 on the axis).
0.33 mark: bar drawn with the same width and spacing as the others and ruled neatly.
Do not credit a bar drawn to 25 or 30, or a point or line instead of a bar.

District F has 63% of homes with superfast broadband. This is between 60 and 79, so it falls in the medium shading class.

1 mark: district F shaded with the medium shading.
0.33 mark: shading matches the key pattern and stays within the district boundary.
Do not credit light or dark shading, or shading of a different district.

Locate 2020 on the x-axis and 19 on the y-axis, which is halfway between the labelled values 18 and 20. Mark the point and draw a straight line from the 2010 point (17%) to it.

1 mark: point plotted at 19% in 2020 (accept 18.5 to 19.5).
0.33 mark: point joined to the 2010 point with a straight line.
Do not credit a bar, or a point that is not joined to the existing line for the second mark.

Hydraulic action and abrasion widen a weakness in a headland to form a cave. Erosion continues through the headland to make an arch. Weathering and erosion weaken the arch roof, which collapses, leaving an isolated stack.

3 x 1 (tick) for each valid point in the sequence, e.g. waves attack a weakness/crack in a headland by hydraulic action or abrasion (1); a cave forms and enlarges until it breaks through to form an arch (1); the arch roof is weakened by weathering/erosion and collapses, leaving a stack (1). Development (DEV) may be credited for naming or explaining a process. Full marks can be awarded for one well-developed sequence. Do not credit a bare list of landforms with no process.

Near the source, vertical erosion dominates, so the valley is narrow and V-shaped with steep sides and interlocking spurs. The channel is small and shallow with a steep gradient and a bed of large angular rocks; waterfalls and rapids may be present.

3 x 1 (tick) for each valid characteristic, e.g. steep-sided/V-shaped valley (1); narrow, shallow channel (1); steep gradient with rapids/waterfalls (1); large angular bed load (1); interlocking spurs (1); vertical erosion dominates (1). Do not credit descriptions of the lower course (floodplain, meanders, wide channel).

Medical advances, better diet and sanitation mean people live longer, increasing the number of older people. Lower fertility, through contraception, careers for women and the cost of raising children, reduces the proportion of young people.

2 x 1 (tick) for each valid reason, plus 1 (DEV) for a further valid explanation of one reason = 3 marks. Examples: increased life expectancy due to better healthcare/NHS/diet (1) so more people survive into old age (DEV); falling birth rate due to contraception/later parenthood/cost of children (1) so the older share of the population rises (DEV); the post-war baby-boom generation is now reaching retirement (1). Do not credit 'people are older' or 'people live longer' with no reason.

Investment in trams, buses and cycle lanes gives people alternatives to private cars, cutting emissions and congestion. Park-and-ride or congestion charges discourage car use in the centre.

2 x 1 (tick) for each valid strategy, plus 1 (DEV) for a developed link to sustainability or reduced congestion = 3 marks. Examples: tram/bus/rail improvements (1) reducing the number of cars and emissions (DEV); cycle lanes/bike hire (1); park-and-ride (1); congestion charge or low emission zone (1). Do not credit building more roads as sustainable.

Regions that relied on mining, steel or shipbuilding lost jobs when these industries closed. Remote areas with poorer infrastructure attract less private investment, and government policy often concentrates spending in the South East.

3 x 1 (tick) for each valid cause, e.g. deindustrialisation/closure of primary or manufacturing industry (1); peripheral location far from London/ports/markets (1); poor road, rail or broadband infrastructure (1); government policy/investment focused elsewhere (1); young skilled people migrate away (1). Do not credit a description of the inequality itself.

The North Atlantic Drift carries warm water from the Gulf of Mexico towards north-west Europe. Air passing over it is warmed and picks up moisture, giving mild winters and cool, wet conditions, particularly in the west.

3 x 1 (tick): it is a warm ocean current flowing from the tropics/Gulf of Mexico (1); it warms the air/prevailing south-westerly winds blowing over it (1); winters are milder than places at the same latitude, e.g. no sea ice in ports (1); moist air brings rainfall, especially to the west (1). Do not credit a bare statement that the UK is warm.

Turbines are tall and visible, spoiling views in scenic areas. Rotating blades create noise and can kill birds and bats. Building access roads and foundations can damage habitats and disturb residents.

3 x 1 (tick) for each valid negative impact, e.g. visual pollution of upland/coastal landscapes (1); noise for nearby residents (1); bird and bat deaths (1); habitat damage during construction (1); possible impact on tourism or house prices (1); intermittent supply (1). Do not credit cost alone without a link to environment or communities.

A warmer atmosphere holds more moisture so intense storms are more common. Building on floodplains and paving over land increases runoff into rivers, so peak flows rise faster. Upland drainage and tree removal speed water to channels.

2 x 1 (tick) for each valid reason, plus 1 (DEV) for a developed explanation = 3 marks. Examples: climate change causes more intense/prolonged rainfall (1) so rivers exceed capacity (DEV); urbanisation creates impermeable surfaces and drains (1) so water reaches rivers quickly, giving a shorter lag time (DEV); deforestation or land drainage reduces interception and infiltration (1); building on floodplains increases the number of events that count as flooding (1). Do not credit 'it rains more' without a cause.

A stack forms in a sequence. Waves exploit weaknesses in a headland through hydraulic action and abrasion, enlarging a crack into a cave. Erosion continues until the cave breaks through to form an arch. Weathering and erosion weaken the arch roof until it collapses, leaving a column of rock separated from the land: a stack.

3 x 1 (tick) for each valid idea, up to a maximum of 3. Development (DEV) marks may be awarded for a further explanation of an identified point; full marks can be awarded for one well-developed explanation.
- Waves erode a weakness/crack in a headland (1) by hydraulic action or abrasion (DEV) to form a cave (1)
- Cave enlarges/erodes through the headland to form an arch (1)
- Arch roof is weakened by erosion/weathering and collapses (1), leaving a stack standing separate from the cliff (DEV)
Accept: valid references to differences in rock resistance. Do not credit: a bare list of landform names without explanation; stack formed by deposition.

Two challenges are explained. First, older people need more healthcare, so GP surgeries, hospitals and care homes may face longer waiting times and staff shortages. Second, a smaller share of the population is of working age, so less tax is raised to pay for pensions and services, putting pressure on the local council budget.

2 x 1 (tick) for each valid challenge identified, plus 1 DEV mark for a further valid explanation of either challenge. Maximum 3 marks.
- Greater demand for healthcare/care homes (1), leading to long waiting times or staff shortages (DEV)
- Fewer working-age people paying taxes (1), so less funding for services or pensions (DEV)
- Need for adapted housing, accessible/cheaper public transport (1), which may be costly to provide (DEV)
- Closure of schools/youth facilities as fewer children (1)
Full marks can be awarded for one well-developed explanation plus one other idea. Do not credit: a bare description of the age structure; vague 'more old people' without link to services.

A tropical continental air mass forms over hot, dry land to the south (such as North Africa). When it moves north over the UK it brings hot, dry air. High pressure can keep it in place, with clear skies and strong sunshine, so temperatures stay high for days, producing a heatwave.

3 x 1 (tick) for each valid point, up to a maximum of 3.
- Air mass originates over hot land to the south, e.g. North Africa/southern Europe (1)
- Air is warm and dry because it has travelled over land, not sea (1)
- Moves north to the UK, often in summer (1)
- Associated with high pressure/slow-moving system keeping it in place for days (1)
- Clear skies allow strong solar heating, giving a heatwave (1)
Accept: valid figures for UK temperature records if relevant. Do not credit: air mass from the north or from the Atlantic; description of rainfall.

Residents may dislike the appearance of tall turbines in a rural landscape, which could reduce tourism and house values. Turbines can also create noise and may harm birds and bats, and construction lorries cause disruption on narrow village roads.

2 x 1 (tick) for each valid reason, plus 1 DEV mark for a further valid explanation of either reason. Maximum 3 marks.
- Visual pollution of rural landscape (1), reducing tourism or house prices (DEV)
- Noise from turbine blades (1), disturbing sleep or residents (DEV)
- Harm to birds/bats or habitats (1), through collisions or construction (DEV)
- Construction traffic/disruption on small roads (1)
- Intermittent energy supply, so not seen as worth the impact (1)
Do not credit: bare 'they don't like it'; reasons in favour of wind farms.

Change = 60 - 24 = 36 TWh.
Percentage increase = \( \frac{36}{24} \times 100 = 150\% \).

Method mark (1): correct method, i.e. (60 - 24) / 24 x 100, or 36 / 24 x 100.
Accuracy mark (1): 150 (%).
Correct answer of 150% with no working scores 2 marks. Accept 150 without the % sign.
Error carried forward: if the difference is miscalculated but the method (difference / 2012 value x 100) is correct, award 1 mark.
Do not credit: 250% (60/24 x 100, which is the 2022 value as a percentage of the 2012 value), or 60% (36/60 x 100, using the wrong base year). Award 0 for these unless the correct method is also shown.

A strong answer names a real UK coastal landscape (e.g. a chalk or limestone coast, or a coast with alternating hard and soft rock). It explains that differential erosion of resistant and less resistant rock forms headlands and bays; that hydraulic action and abrasion exploit joints and faults to form caves, which are enlarged to arches and then collapse to leave stacks; and that longshore drift and deposition form beaches or spits where the coast changes direction or sheltered water allows sediment to build up. It uses local detail (named features, rock types, wave direction) and links geology to process to landform.

AO1 (2 marks): knowledge of place-specific geology and landforms. AO2 (4 marks): understanding of how processes and geology interact.

Level 3 (5-6 marks) Thorough: accurate, detailed explanation linking geology (rock type, joints, hard/soft rock) with specific processes (hydraulic action, abrasion, attrition, solution, longshore drift, deposition) to at least two named landforms; well-developed place-specific detail; a sustained, coherent line of reasoning.
Level 2 (3-4 marks) Reasonable: some explanation of how processes create landforms, with partial or general links to geology; some place detail.
Level 1 (1-2 marks) Basic: simple, generic description of landforms or processes; little or no link to geology or to the case study.
0 marks: no creditable response.

Cap: if the case study is not a UK coastal landscape, or no place is identified, maximum Level 2 (4 marks).

Indicative content (not exhaustive; valid alternatives credited): differential erosion of hard and soft rock; wave refraction concentrating energy on headlands; joints and faults exploited by hydraulic action; cave-arch-stack sequence; longshore drift moving sediment; deposition in sheltered bays or at river mouths; effect of climate and sea level; role of human management in shaping the coast.

Examples: Well-developed: 'At my coast, resistant chalk forms headlands while softer clay erodes to form a bay. Waves attack a crack in the headland by hydraulic action, widening it into a cave, and abrasion then erodes through to form an arch...' Developed: 'Hard rock sticks out as headlands and waves make caves that become arches.' Simple: 'Waves erode the cliffs and make caves.'

A strong answer identifies the challenge (e.g. traffic congestion, housing availability or waste management) and one named strategy (e.g. a tram or cycle network, a low emission zone, brownfield housing regeneration or a recycling scheme). It outlines how it works and gives evidence of success (reduced car use, improved air quality, more homes, higher recycling rates, jobs). It then weighs limitations (cost, uneven benefits across areas, displacement, continued problems) and reaches a justified judgement about overall success.

AO1 (2 marks): knowledge of the city, challenge and strategy. AO2 (2 marks): understanding of how the strategy works and its impacts. AO3 (4 marks): evaluation and judgement.

Level 3 (6-8 marks) Comprehensive/Thorough: detailed, place-specific knowledge of one strategy; balanced consideration of successes and limitations across social, economic and environmental dimensions; a clear, supported judgement (evaluation may be implicit at the lower end of the level).
Level 2 (3-5 marks) Reasonable: some relevant detail on the strategy and some impacts; limited or one-sided evaluation; judgement partial or weakly supported.
Level 1 (1-2 marks) Basic: generic or simple statements about the challenge or strategy; little place detail; no evaluation.
0 marks: no creditable response.

Caps: if the city is not a UK city, or the strategy is not sustainable or not linked to a challenge, maximum Level 2. If more than one strategy is discussed, credit the best only.

Indicative content (not exhaustive): public transport schemes, cycling infrastructure, congestion or low emission zones; regeneration of brownfield sites and affordable housing; recycling and waste-to-energy; community involvement; cost and funding; long-term versus short-term benefits; who gains and who loses; ongoing problems.

A strong answer names a UK flood event caused by extreme weather and briefly states its causes and effects. It then evaluates local management (quick, tailored, protects specific properties, but limited area, may increase flood risk downstream, depends on community resources) against national management (flood warnings, funding, coordinated catchment planning and policy, but slower, may not reflect local needs, cost-benefit priorities leave some areas unprotected). It reaches a justified conclusion, for example that effectiveness depends on cooperation between the scales, using evidence from the event.

12 marks: AO1 (3 marks) knowledge of the flood event and management; AO2 (3 marks) understanding of how management works at different scales; AO3 (6 marks) evaluation and judgement. Plus 3 SPaG marks.

Level 4 (10-12 marks) Comprehensive: detailed, accurate place-specific evidence on both local and national management; sustained, balanced evaluation of effectiveness; a clear, well-supported conclusion that addresses 'to what extent'.
Level 3 (7-9 marks) Thorough: good knowledge of the event and management at both scales; some evaluation with supporting evidence; a conclusion that is mostly supported.
Level 2 (4-6 marks) Reasonable: some relevant knowledge, perhaps more on one scale; limited evaluation; conclusion simple or partly supported.
Level 1 (1-3 marks) Basic: generic statements about flooding or defences; little place detail; no real evaluation.
0 marks: no creditable response.

Cap: if the case study is not a UK flood event caused by extreme weather, maximum Level 2 (6 marks). Evaluation may be implicit at lower levels.

Indicative content (not exhaustive; valid alternatives credited): causes (prolonged rainfall, saturated soils, steep relief, urbanisation); effects (damage to homes, disruption to transport and business, stress, pollution, habitat damage); local management (flood walls, embankments, temporary barriers, community flood wardens, resilient building); national management (forecasting and warnings, government funding, planning policy, catchment-scale schemes, insurance); limitations of each; cooperation between scales.

SPaG (3 marks): High performance (3): spelling and punctuation consistently accurate; grammar controlled; wide range of specialist terms used accurately. Intermediate (2): considerable accuracy; good range of terms. Threshold (1): reasonable accuracy; some specialist terms. 0: errors prevent meaning, or no creditable response.

The SPaG marks are awarded for the quality of written English in the extended response, not for the geography itself. A strong response would be clearly organised and would spell and punctuate accurately. It would use specialist terms such as renewable, non-renewable, fossil fuels, energy mix, carbon emissions, sustainable, intermittent supply, national grid, offshore wind, fracking, energy security and demand. Example of high-performance writing: 'Offshore wind farms generate low-carbon electricity, but supply is intermittent because it depends on wind speed. Therefore, gas-fired power stations are still needed to maintain energy security.'

SPaG grid (applied to the response to the 12-mark question; the geographical content is marked separately):

High performance [3 marks]: spelling and punctuation are consistently accurate; rules of grammar are used with control and meaning is clear throughout; a wide range of specialist terms is used adventurously and correctly.

Intermediate performance [2 marks]: spelling and punctuation are generally accurate with minor errors; grammar is mostly controlled and meaning is clear; a good range of specialist terms is used, mostly correctly.

Threshold performance [1 mark]: spelling and punctuation are accurate in places, with some errors; some control of grammar and meaning is generally clear; a limited range of specialist terms is used, with some accuracy.

No marks [0]: errors in spelling, punctuation and grammar severely hinder meaning; no or very few specialist terms; or no creditable response.

Notes: Award 0 if the response is too brief or too off-topic to judge. Specialist terms must be used correctly in context (a bare list does not gain credit). Do not penalise the candidate on SPaG for the choice of case study; mark the quality of writing seen. Terms that may be credited include: renewable, non-renewable, fossil fuel, energy mix, energy security, carbon emissions, sustainable, intermittent, national grid, offshore wind, fracking, nuclear, demand, supply, subsidy.

Biotic components are the living parts of an ecosystem (plants, animals, fungi, humans). Fungi are living organisms, so B is correct. Soil acidity, rainfall and temperature are abiotic (non-living) factors.

1 mark for B only. Do not credit more than one letter. A, C and D are abiotic components.

GNI per capita is an economic development indicator showing the average income per person. The other options are physical features that do not measure development.

1 mark for A only. Do not credit more than one letter.

Rapid decomposition and heavy rainfall leaching mean the soil is nutrient-poor. Nutrients are taken up quickly by roots and held in the biomass of the trees and other plants, so B is correct.

1 mark for B. Do not credit any other letter. A is wrong because tropical rainforest soils are thin and nutrient-poor; C and D are not the main stores in the nutrient cycle.

Hot, humid conditions let decomposers break down fallen leaves within weeks. Nutrients are released into the top few centimetres of soil and taken up rapidly by shallow roots, then stored in the biomass. Little is stored in the soil itself, so the cycle depends on the constant supply of litter.

Max 2.6 (1 + 1 + 0.6). 1 mark for each valid point, with the third valid point worth 0.6. Development (DEV) of a point can count as a further point; full marks can be awarded for one well-developed explanation.
Indicative content:
- warm, moist climate speeds up decomposition by fungi and bacteria (1)
- nutrients released into the topsoil and absorbed quickly by shallow roots (1)
- heavy rain can wash (leach) nutrients away, so quick uptake is needed (1)
- most nutrients are held in the biomass, not the soil (1)
Do not credit: a bare statement that the rainforest is wet or hot with no link to nutrients.

Example using the Great Barrier Reef: agricultural run-off carries fertiliser and sediment onto the reef, causing algal growth that blocks light and harms the zooxanthellae. Anchors and careless divers break fragile coral, reducing habitat for fish.

Max 2.6 (1 + 1 + 0.6). Award 1 for each valid threat identified, plus development marks for an explained impact on biodiversity; the final point is worth 0.6. A named reef must be a real reef (e.g. Great Barrier Reef, Mesoamerican Barrier Reef, Red Sea, Florida, Andros, New Caledonia) for the case-study context.
Indicative content: pollution and run-off, overfishing, tourism damage, anchors, warming oceans and bleaching linked to human emissions.
Do not credit: a bare term such as 'pollution' with no explanation.

GNI per capita is collected for nearly every country, so comparisons are quick and quantitative. However, it is an average: a few very wealthy people can raise it while most live in poverty. It also says nothing directly about life expectancy or literacy, unlike the Human Development Index.

Max 2.6 (1 + 1 + 0.6). 1 mark for a valid advantage, 1 mark for a valid disadvantage, and development of either point earns the remaining 0.6.
Advantages: single figure, easy to rank, widely available, economic measure.
Disadvantages: average hides inequality; ignores social or environmental aspects; informal economy not counted; exchange rates distort values.
Do not credit: 'it is not accurate' with no reason.

Rural families often depend on small farms. When harvests fail or land is too small, income falls and people leave to look for paid work in cities. Remote villages may also lack hospitals and secondary schools, so families move to access services.

Max 2.6 (1 + 1 + 0.6). 1 mark per valid push factor, with development marks for an explained link to migration; last point worth 0.6.
Indicative content: unemployment or low wages; crop failure, drought or flooding; conflict; poor services; mechanisation reducing farm jobs.
Do not credit: pull factors (e.g. better jobs in the city) unless they are reworded as a rural problem.

Long-term aid, such as funding for rural schools, increases literacy and later productivity. However, aid tied to buying donor-country goods benefits the donor, and corruption can divert money from the people who need it.

Max 2.6 (1 + 1 + 0.6). 1 mark for a valid way aid helps, 1 mark for a valid way it hinders, and 0.6 for development of either point.
Indicative content: helps - infrastructure, health, education, reduced poverty; hinders - dependency, tied aid, corruption, unsuitable projects, debt if loans.
Do not credit: 'it gives them money' alone.

Each year's snowfall forms a layer, so depth gives age. Air bubbles reveal past greenhouse gas concentrations, and oxygen isotope ratios in the ice indicate the temperature when the snow fell. Comparing layers shows warm and cold periods.

Max 2.6 (1 + 1 + 0.6). 1 mark per valid point; development marks for explained links.
Indicative content: layers represent years, deeper means older; gas in bubbles shows past carbon dioxide levels; oxygen isotopes show temperature; allows comparison of glacial and interglacial periods.
Do not credit: 'it shows the temperature' with no method.

Warm water evaporates, and rising moist air condenses, releasing latent heat that powers the storm. Over land the moisture source is removed and friction with the surface slows the winds, so the system loses energy and decays.

Max 2.6 (1 + 1 + 0.6). 1 mark for each valid idea; 0.6 for the last developed point.
Indicative content: sea temperature of at least about 27 degrees Celsius over a depth of 50 m; evaporation gives moisture and energy; condensation releases latent heat; land removes the moisture supply; friction reduces wind speed.
Do not credit: 'because land is colder' with no development.

Increase = 34 - 10 = 24. Percentage increase = \( \frac{24}{10} \times 100 = 240\% \).

Max 2.6. Method: 1 mark for the increase (34 - 10 = 24) or for dividing the change by the original value; 1 mark for \( \frac{24}{10} \times 100 \); 0.6 mark for the correct answer of 240% (accept 240). Correct answer with no working: 2.6. Error carried forward allowed if the method is correct. Do not credit 340% (using the new value as a ratio) or 70.6% (dividing by the final value).

Rainforest: warm, humid conditions make decomposers very active, so leaf litter breaks down within weeks and nutrients are taken up quickly by shallow roots. Heavy rainfall leaches nutrients from the soil, so the biomass store is the largest. Temperate forest: cooler conditions and a seasonal leaf fall slow decomposition, so a thicker litter layer and a larger soil store build up.

3 x 1 (tick) for each valid idea, including development (DEV) marks. Full marks can be awarded for one well-developed explanation.
- Rainforest decomposition is rapid due to heat and moisture (1) so litter store is small / nutrients are recycled quickly (DEV 1).
- Most nutrients are in the biomass store in the rainforest (1).
- Heavy rainfall leaches nutrients so the soil store is small (1).
- Temperate forests have slower decomposition because of cooler temperatures / leaf fall in autumn, so larger litter and soil stores (1).
Do not credit: a bare statement that rainforests have more plants; description with no comparison.

Two strategies are needed, each with a reason it works. For example, a marine protected area bans destructive fishing such as dynamite or trawling, so coral structure and reef fish populations recover. Limiting boat anchoring by providing fixed moorings prevents anchors breaking coral, so reef cover is maintained.

3 marks: 2 x 1 for two valid management strategies, plus 1 DEV mark for a valid explanation of how either reduces the threat. Full marks can be awarded for one well-developed point plus one identified point.
Accept: marine protected areas; fishing quotas or bans; limits on visitor numbers; fixed moorings; reducing run-off from farms; education schemes; coral nurseries / restoration.
Do not credit: a bare 'protect the reef'; reducing climate change without any specific reef-scale link. Strategy should relate to a reef.

Advantage: GNI per capita is a quantitative figure available for almost every country, so countries can be ranked and compared easily. Disadvantage: it is a mean, so a wealthy minority can raise the figure while most people stay poor; it also does not show quality of life, such as access to healthcare or education, so a composite measure such as HDI may be fairer.

3 marks: 1 for a valid advantage, 1 for a valid disadvantage, 1 DEV for development of either.
Accept advantages: simple, easy to compare, data widely available, economic measure.
Accept disadvantages: average hides inequality; does not include social/environmental factors; informal economy not counted; differences in cost of living.
Do not credit: 'it is inaccurate' without reason.

Increase = 3.0 - 2.4 = 0.6 million. Percentage increase = \( \frac{0.6}{2.4} \times 100 = 25\% \).

3 marks:
- 1 for the correct increase (0.6 million or 600 000).
- 1 for the method: increase divided by original, multiplied by 100.
- 1 for the correct answer, 25 (%).
Allow error carried forward where working is shown. Correct answer with no working gains full marks. Do not credit 20% (dividing by the new figure) beyond the first mark.

Choose two from ice cores, tree rings, historical diaries/paintings, or temperature records. Each needs the type of evidence and what it reveals about past climate. E.g. ice cores contain layers of snow with trapped gases from which temperature can be inferred; tree rings vary in width with growing conditions each year.

3 marks: 2 x 1 for two valid evidence types, plus up to 1 further mark for a valid statement of what a type shows (maximum 3). Credit a clear explanation of one type as DEV.
Accept: ice cores, tree rings, paintings (e.g. frost fairs), diaries, instrumental temperature records, pollen or sediment records.
Do not credit: 'satellites' or 'weather forecasts' for pre-modern climate.

Warm ocean water above about 27 degrees C evaporates and the moist air rises, condensing and releasing latent heat that drives the storm. Once over land the moisture and heat source is lost and friction with the surface slows the winds, so the storm decays.

3 x 1 (tick) for each valid idea, including DEV marks.
- Sea temperature of 27 degrees C or more / warm water (1).
- Evaporation provides moisture and energy, causing rising air / low pressure (DEV 1).
- Over land the source of heat and moisture is removed (1).
- Friction over land reduces wind speed (1).
Do not credit: a bare 'land is cold'; description of storm movement with no reason.

Example answer (Great Barrier Reef). Warming seas linked to the enhanced greenhouse effect raise water temperature, so corals expel the symbiotic algae that feed them and bleach. Where bleaching is severe the coral dies, and the fish, molluscs and crustaceans that depend on it for food and shelter decline, so biodiversity falls. Fertiliser and sediment washed from farmland on the Queensland coast add nutrients, which encourage algae to smother coral and cut the light reaching it. Crown-of-thorns starfish thrive on this nutrient-rich water and eat large areas of living coral. Boat anchors and careless snorkellers break fragile branching corals, and overfishing of grazing fish lets algae spread, which further reduces the variety of species.

AO1 (2 marks): knowledge of the reef and threats. AO2 (4 marks): understanding of how the threats reduce biodiversity through links in the ecosystem.

Level 3 Thorough (5-6 marks): Detailed, accurate place-specific knowledge. Two or more threats explained through clear chains of cause and effect, showing interdependence of abiotic and biotic components (e.g. temperature, symbiotic algae, coral, fish). Sustained, coherent reasoning.
Level 2 Reasonable (3-4 marks): Some accurate knowledge with some place detail. At least one threat explained with some linkage to biodiversity loss.
Level 1 Basic (1-2 marks): Simple, generic statements about threats with little or no explanation or detail.
0 marks: no creditable response.

Indicative content (not exhaustive; valid alternatives credited): ocean warming and bleaching; nutrient and sediment runoff; algal blooms; crown-of-thorns outbreaks; overfishing and removal of grazers; tourism damage such as anchors, trampling and sunscreen; coastal development; oil or plastic pollution; ocean acidification.

Caps: if the case study is not a coral reef, or no named place is evident and the answer is wholly generic, cap at Level 1. Description of threats without any link to biodiversity cannot exceed Level 1 (2 marks). Do not credit management or mitigation strategies unless used to explain a threat.

Example answer (Curitiba, Brazil: transport). The challenge was traffic congestion and air pollution as the city grew rapidly. The strategy was a bus rapid transit system with dedicated lanes, tube-shaped stations with pre-paid boarding, and bi-articulated buses. It succeeded in moving large numbers of commuters cheaply, cutting car use per person and reducing emissions, and it is affordable for poorer residents so it is socially sustainable. It was also cheaper than building an underground railway. However, buses are now overcrowded at peak times, and outlying low-income neighbourhoods are less well served, so some problems remain. Overall the strategy has been largely successful but not completely, because demand has outgrown capacity.

AO1 (2 marks): knowledge of the city, challenge and strategy. AO2 (3 marks): understanding of how the strategy works and its effects. AO3 (3 marks): evaluation and judgement of success.

Level 3 Thorough (6-8 marks): Accurate, detailed place-specific knowledge of a strategy and challenge. Clear explanation of how the strategy addresses the challenge in a sustainable way (social, economic, environmental). Balanced evaluation of successes and limitations leading to a supported judgement about the extent of success.
Level 2 Reasonable (3-5 marks): Some accurate knowledge with some place detail. Some explanation of how the strategy works. Some evaluative comment, which may be one-sided or the judgement may be partial.
Level 1 Basic (1-2 marks): Simple, generic statements with little place detail. Little or no evaluation.
0 marks: no creditable response.

Indicative content (not exhaustive; valid alternatives credited): scale of the problem; aims of the strategy; cost and affordability; community involvement; improved living conditions, travel times or waste collection; reduced pollution; reach to the poorest groups; population growth outpacing the scheme; long-term maintenance and funding; continuing informal settlement or congestion.

Caps: if the city is not in an LIDC or EDC, or the strategy is not sustainable or does not address a contemporary challenge, cap at Level 2 (5 marks). Evaluation may be implicit. Top of Level 3 needs a clear judgement.

Example answer (2015-16 El Niño drought, Ethiopia). During El Niño the Pacific warm water shifts east, which weakens the trade winds and disrupts atmospheric circulation. Rain-bearing winds over the Ethiopian highlands fail, so the kiremt rains were poor and crops failed. Millions needed food aid, livestock died and rivers and water holes dried up, which supports the view that people have little power. However, people have adapted: some farmers switched to drought-tolerant crops, built small ponds and terraces to hold water, and the government and charities delivered food and water; early-warning systems improved preparation. These steps reduced deaths compared with the 1984 famine. Yet poverty, poor roads and the scale of the failure limited what could be done, so adaptation was only partly effective. I therefore agree only partly: people can reduce the impact, but poorer communities remain highly vulnerable.

12 marks: AO1 (3 marks), AO2 (4 marks), AO3 (5 marks). Plus 3 marks SPaG (separate grid below).

Level 3 Comprehensive/Thorough (9-12 marks): Detailed, accurate knowledge of the named event, with specific facts and figures. Thorough understanding of how El Niño/La Niña created the drought and of effects and adaptations. Sustained evaluation weighing the effectiveness and limits of adaptation, leading to a well-supported judgement about the extent of agreement. Coherent line of reasoning.
Level 2 Reasonable (5-8 marks): Mostly accurate knowledge with some place detail. Some understanding of causes, effects and adaptations. Some evaluation, perhaps one-sided or with a partial or unsupported judgement.
Level 1 Basic (1-4 marks): Simple, generic statements about drought with little place detail. Little or no link to the statement or evaluation.
0 marks: no creditable response.

Indicative content (not exhaustive; valid alternatives credited): shifting Pacific warm water and altered air circulation; failed rains; crop and livestock losses; food and water shortages, health problems, migration; loss of vegetation and soil erosion, falling reservoir levels; adaptations such as water storage, drought-resistant crops, irrigation, water rationing, early warning, aid and cloud seeding; limits due to poverty, cost, scale and governance.

Caps: if the event is not an El Niño/La Niña drought, cap at Level 2 (8 marks). An answer with no adaptation content cannot exceed Level 2. Evaluation may be implicit.

SPaG (3 marks): High 3 = spelling and punctuation accurate, grammar controlled, wide range of specialist terms used accurately. Intermediate 2 = considerable accuracy, good range of terms. Threshold 1 = reasonable accuracy, some specialist terms. 0 = errors impede meaning, or no response worthy of credit.

The task is to write a short, well-organised paragraph on a named coral reef that responds to the statement. The SPaG marks reward writing accuracy and the precise use of terms from the specification (e.g. biodiversity, interdependence, nutrient cycling, bleaching, sustainable, mitigation, threat). The content itself is not credited here, but the response must be relevant enough to give a sufficient amount of writing to judge. A typical 3-mark response is accurate throughout, with sentences and paragraphing that are clear and a wide range of terms used correctly.

SPaG grid (0-3 marks), judged on the candidate's response to the statement:

3 marks (High performance): Spelling and punctuation are consistently accurate; rules of grammar are used with control; meaning is very clear. A wide range of specialist terms is used accurately and appropriately (at least four relevant geographical terms used correctly).

2 marks (Intermediate performance): Spelling and punctuation are generally accurate, with minor errors that do not hinder meaning. Grammar is mostly controlled; meaning is clear. A good range of specialist terms is used, mostly correctly (two or three terms).

1 mark (Threshold performance): Spelling and punctuation are reasonably accurate, though errors may occasionally hinder meaning. Some control of grammar. A limited range of specialist terms is used, with some accuracy (one term).

0 marks: No response, or the response is not worthy of credit; errors in spelling, punctuation and grammar severely hinder meaning; no specialist terms, or the response is not relevant to the topic of coral reefs.

Notes: Do not credit a response that is too brief to allow SPaG to be judged (cap at 1 mark). Do not credit specialist terms that are merely listed and not used in context. Credit any valid case study; the accuracy of the content is not assessed by this grid but a response must relate to coral reefs. Accept a reasonable agree or disagree stance; the stance does not affect the SPaG mark.

Order the data: 8, 11, 11, 14, 21. The middle (third) value is 11 m. The mean is 65 ÷ 5 = 13 m (distractor D). 8 m is the minimum value (distractor A). 10 m is not in the data set and is not the median (distractor B).

1 mark for C (11 m). Do not credit any other letter. Common error: calculating the mean (13 m) instead of the median.

Vertical rise = 320 − 120 = 200 m. Horizontal distance = 2 km = 2000 m. Gradient = 200 : 2000 = 1 : 10, so 1 in 10.

1 mark for B (1 in 10). Do not credit any other letter. Common error: forgetting to convert km to m, or using 320 m as the vertical rise.

The sector is 72 ÷ 360 = 0.2 (20%) of the whole. 0.2 × 300 = 60 TWh.

1 mark for D (60 TWh). Do not credit any other letter. Common error: giving the percentage (20) or dividing the angle incorrectly.

A larger sample reduces the effect of anomalies and makes the mean at each site more representative, increasing reliability. B reduces the data collected, C introduces bias, and D reduces accuracy.

1 mark for A. Do not credit any other letter.

Increase = 20.0 - 12.5 = 7.5 TWh.
Percentage increase = \( \frac{7.5}{12.5} \times 100 = 60\% \).

Method mark (1): correct method, i.e. difference divided by original value, multiplied by 100 (e.g. \( \frac{7.5}{12.5} \times 100 \)).
Accuracy mark (1): 60 (%).
Correct answer of 60% with no working gains 2 marks.
Error carried forward allowed for the accuracy mark if the method is correct but the subtraction is wrong.
Do not credit: 160% or 37.5% (calculated using the wrong base year) for the accuracy mark; method mark may still be awarded if the method is otherwise clear.

Sum = 0.42 + 0.55 + 0.61 + 0.48 + 0.69 = 2.75.
Mean = \( \frac{2.75}{5} = 0.55 \) m/s.

Method mark (1): adds all five values and divides by 5 (e.g. \( \frac{2.75}{5} \)).
Accuracy mark (1): 0.55 (m/s).
Correct answer with no working gains 2 marks.
Error carried forward allowed for the accuracy mark if the sum is incorrect but divided by 5.
Do not credit: median (0.55 is coincidentally equal, so only credit if the working shows the mean method); dividing by a number other than 5 gains no method mark.

Sum = 4 + 7 + 5 + 9 + 5 + 6 = 36. Mean = 36 / 6 = 6 cm. Range = largest - smallest = 9 - 4 = 5 cm.

Mean: 1 mark for method (sum divided by 6, or 36 / 6), 1 mark for 6 cm. Range: 1 mark for 5 (cm). Total 3. Error carried forward allowed for the mean if the sum is mis-added but divided by 6. Do not credit range given as '4-9' without a value of 5.

Wind direction is data arranged around compass points, so a rose chart or radial graph shows at a glance which direction is most frequent (west).

1 mark for a suitable graph: rose chart, wind rose or radial graph. 1 mark for a reason, e.g. it shows direction as well as frequency; the dominant direction is easy to see; categories are compass directions. A bar graph may be credited 1 mark for the graph with a valid reason (compares frequency) but the reason must link to the data. Do not credit a pie chart, line graph or scatter graph with no valid reasoning. Reason cannot be awarded without a valid graph.

7.4 cm x 25 000 = 185 000 cm = 1850 m = 1.85 km. (Equivalent: 1 cm = 0.25 km, so 7.4 x 0.25 = 1.85 km.)

1 mark for method (7.4 x 25 000 or 7.4 x 0.25). 1 mark for 1.85 km. Accept 1.8-1.9 km only if working is shown. Do not credit an answer in metres or centimetres without conversion to km. Error carried forward for the answer mark if the method is correct.

Vertical rise = 80 - 40 = 40 m. Horizontal distance = 1.6 km = 1600 m. Gradient = 1600 / 40 = 1 in 40.

1 mark for method: rise 40 m and distance converted to 1600 m, divided correctly. 1 mark for 1 in 40. Do not credit 40/1600 left unsimplified if the answer is not given as 1 in X. Award 1 mark (method) if units are not converted but the working is otherwise correct (e.g. 1.6 / 0.04 shown consistently).

Compare each age group with the UK figure: older group is 8 percentage points higher, young group is 5 percentage points lower.

2 x 1 (tick) for each valid comparison using data: the proportion aged 65+ is higher (27% compared with 19%, 8 percentage points more); the proportion aged 0-14 is lower (12% compared with 17%). Both must be comparative. Do not credit statements with no data or with no comparison to the UK.

Increase = 27 - 9 = 18. Percentage increase = 18 / 9 x 100 = 200%.

1 mark for method (increase divided by original x 100, or 18 / 9 x 100). 1 mark for 200%. Do not credit 18% (percentage point change) as the final answer, though the working mark may be given.

Reliability improves with larger samples and unbiased selection, and by repeating the survey or adding more sites so patterns are not due to chance.

Up to 3 marks. Each valid improvement 1 mark, with 1 further (DEV) mark for a reason, to a maximum of 3, e.g. larger sample (1) so anomalies have less effect on the mean (DEV); random sampling (1) to avoid bias towards larger or easier-to-reach pebbles (DEV); more sites or repeat measurements (1) to show a clear trend (DEV); measure the same axis with the same ruler (1) for consistency. Full marks can be awarded for one well-developed point plus a second idea. Do not credit 'be more careful' or 'use better equipment' without detail.

Identify the weakness (1) and develop why it affects the conclusions (1).

1 mark for a weakness: small sample; one location outside a coffee shop; one time/day; not random or may be biased. 1 mark (DEV) for explaining the effect, e.g. results may not be representative of people at other times, so conclusions about the whole town centre may be unreliable. Do not credit 'it was boring' or 'people refused' without a link to the sample.

Total = 12 + 8 + 25 + 31 + 6 + 14 + 8 = 104 mm. Mean = \( 104 \div 7 = 14.857... \approx 14.9 \) mm.

1 mark for method: total divided by 7 (accept 104 / 7).
1 mark for correct answer 14.9 (mm).
Correct answer with no working gets 2 marks. Do not credit 14.86 or 15 if 1 d.p. is not given (14.857 may be awarded the method mark only). Error carried forward allowed if the total is mis-added but is divided by 7.

Angle = \( \frac{28}{100} \times 360 = 100.8^{\circ} \), so about \( 101^{\circ} \).

1 mark for method: 28/100 x 360 (or 28 x 3.6).
1 mark for correct answer: accept 100.8 or 101 degrees; accept anything between 100 and 101.
Correct answer with no working gets 2 marks. Do not credit 28 degrees or an answer with no units/degrees only if clearly a different quantity.

(i) 6.4 cm x 25 000 = 160 000 cm = 1600 m = 1.6 km.
(ii) Height gain = 120 - 40 = 80 m. Horizontal distance = 1600 m. Gradient = 1600 / 80 = 1 in 20.

(i) 1 mark for 1.6 km (accept 1600 m if clearly converted).
(ii) 1 mark for method: height difference 80 m divided into 1600 m (ecf from (i)). 1 mark for correct answer 1 in 20 (accept 5% or 80/1600).
Do not credit a gradient of 1 in 0.05 or 20 without a 'in' form if the working is absent.

Reliability improves when more readings are taken and averaged, which reduces the effect of anomalies, and when readings are taken across the channel because velocity varies from bank to centre.

2 x 1 (tick) for each valid idea, e.g.: repeat each reading (at least three times) and take a mean; take readings at several points across the channel / bank and centre; take readings at several cross-sections; use the same person and equipment each time; use a flow meter as well as a float for comparison; remove anomalies.
Do not credit: 'be more careful', 'use a better method' or 'take more time' without detail. One mark per distinct idea; no marks for repeating the same idea.

Normally warm water and rising moist air bring rain to the western Pacific. In El Niño the trade winds weaken and warm water moves east, so air above Australasia sinks. Sinking air is dry and stops cloud forming, so rainfall falls below normal and drought develops.

1 mark for identifying a valid point and 1 mark (DEV) for development / explanation. Full marks can be awarded for one well-developed explanation.
Indicative: trade winds weaken / warm water moves east (1); so less evaporation and rising air over Australasia, with high pressure and sinking dry air (DEV); so less cloud and rainfall, drought (DEV).
Do not credit: description of drought effects only, or 'it gets hot' with no link to rainfall.

GNI per capita is a single economic average. Two countries can have the same figure but very different wealth distribution, life expectancy or schooling, so it gives an incomplete picture of development.

1 mark for a valid disadvantage and 1 mark (DEV) for explaining why this limits comparison. Full marks can be awarded for one well-developed explanation.
Indicative: it is an average so hides inequalities (1) so many people may be far poorer than the figure suggests (DEV); it only measures economic wealth, not social or environmental development, e.g. health or education (1) so a country could appear more developed than it is (DEV); informal economy not recorded; different currencies / cost of living.
Do not credit: a bare statement such as 'it is not accurate' or 'it is only about money' with no development.

Wind turbines at sea use a renewable resource and release no greenhouse gases during generation, helping the UK reduce emissions. Winds offshore are stronger and more constant than on land, giving reliable output and cutting dependence on imported gas.

1 mark for a valid reason and 1 mark (DEV) for development. Full marks can be awarded for one well-developed explanation.
Indicative: renewable / low carbon (1) so reduces greenhouse gas emissions and helps meet international targets (DEV); stronger, more consistent winds offshore (1) so higher output (DEV); reduces dependence on imported fuels (1) improving energy security (DEV); creates jobs in coastal areas.
Do not credit: 'it is cheap' or 'it is good for the environment' with no development.

Worked data: renewables 2005 = 2 + 0 + 5 = 7%; 2025 = 29 + 5 + 12 = 46%, an increase of 39 percentage points. Coal fell by 33 points (34 to 1). Gas fell only 5 points (36 to 31) so remains the largest single source. Nuclear fell 20 to 14.

A strong answer: (for) rapid growth already achieved, trend suggests renewables could pass 50% well before 2040, coal almost eliminated, jobs and climate targets (Fig. B), UK has good wind resource and long coastline, falling costs; (against) wind and solar are intermittent so need back-up and storage, gas still 31% and sets prices (Fig. B), local opposition over visual impact and tourism, high grid and construction costs, nuclear provides steady low-carbon supply, imports 8% show security issues. Judgement: 'mainly' (over 50%) is realistic by 2040 provided storage and grid investment, but not complete reliance; some gas/nuclear will remain as a stable base.

Levels of response (AO2 = 2 marks, AO3 = 5 marks approx.; marked holistically).

Level 3 (Thorough/Comprehensive) 6-7 marks: Sustained, balanced evaluation using data from Fig. A (with manipulation, e.g. 7% to 46%) AND points from Fig. B, linked to own understanding (intermittency, storage, nuclear, gas, costs, security of supply, targets). Reaches a clear, supported judgement on 'to what extent'. 7 marks needs well-developed linkage between sources and a convincing conclusion; 6 marks where one side is less developed.

Level 2 (Reasonable) 3-4 marks (5 if only one source of evidence is well used): Some use of Fig. A and/or Fig. B with partly developed explanation; may be one-sided or the judgement may be weakly supported.

Level 1 (Basic) 1-2 marks: Simple, generalised statements or copying of figures with little link to the statement; no judgement or an unsupported one.

Level 0: No creditable response.

Indicative content (not exhaustive; valid alternatives credited): Fig. A: renewables 7% to 46%; coal 34% to 1%; gas 36% to 31%; nuclear 20% to 14%; imports 3% to 8%. Fig. B: 400 jobs, climate targets, tourism/visual impact, intermittency, gas price dependence. Own knowledge: UK wind resource, energy mix management, government policy, nuclear as low-carbon base load, battery storage and interconnectors, costs.

Accept: any reasonable calculation from the table. Evaluation may be implicit. Do not credit: bare statements such as 'renewables are good' without link to the evidence. Cap: answers that use neither figure cannot exceed Level 1; answers using only the figures with no own understanding cannot exceed Level 2.

Worked data: population increase = 5.9 - 1.2 = 4.7 million; percentage increase = 4.7 / 1.2 x 100 = about 392%. Number living in informal settlements in 2020 = 38% of 5.9 million = about 2.24 million (in 1990: 22% of 1.2 million = about 0.26 million), so the number living in informal housing has increased roughly eight to nine times, faster than the city as a whole.

A strong answer: (problems) informal settlements, hazard-prone slopes and river banks, water shortages, long commutes, strain on services, pollution; (benefits) jobs in factories, access to clinics and schools, economic growth, migrants' remittances, improvements such as bus rapid transit and water kiosks (Fig. D); push factors (falling farm incomes) show alternatives for migrants are worse. Judgement: problems are growing faster than solutions in Kandara, so broad agreement is reasonable, although benefits are real and management schemes are beginning to help; the balance depends on whether investment keeps pace with growth.

Levels of response (AO2 = 2 marks, AO3 = 5 marks approx.; marked holistically).

Level 3 (Thorough/Comprehensive) 6-7 marks: Balanced, developed evaluation using data from Fig. C (with manipulation, e.g. percentage or numbers in informal settlements) AND Fig. D, supported by own understanding of the causes and consequences of rapid urbanisation (push and pull factors, social, economic and environmental effects, management strategies). Gives a clear, justified judgement. 7 marks needs convincing linkage and conclusion; 6 marks where one side is less developed.

Level 2 (Reasonable) 3-4 marks (5 if only one source is well used): Some use of the figures and some explanation of problems and/or benefits; limited balance or weakly supported judgement.

Level 1 (Basic) 1-2 marks: Simple, generalised statements or lifting of figures with little explanation; no judgement or unsupported one.

Level 0: No creditable response.

Indicative content (not exhaustive; valid alternatives credited): Fig. C: 1.2m to 5.9m (about 392% increase, accept 390-393%); informal share 22% to 38% (about 0.26m to 2.24m people, accept 2.2-2.3m). Fig. D: push factors (falling farm incomes, distant schools), pull factors (factory work, clinics), long commutes, water shortage, hazardous sites, bus rapid transit, water kiosks. Own knowledge: natural growth, pressure on housing, waste, pollution, informal economy, economic growth, remittances, sustainable strategies.

Accept: correct calculations with working; error carried forward where working is shown. Evaluation may be implicit. Do not credit: bare description of 'overcrowding' with no link to the evidence. Cap: answers using neither figure cannot exceed Level 1; answers that only describe the figures without own understanding cannot exceed Level 2.

Total = 42 + 58 + 35 + 61 + 54 = 250. Mean = 250 / 5 = 50 people per 10 minutes.

2 marks. 1 mark for method (adding all five values and dividing by 5, or 250 / 5). 1 mark for correct answer of 50. Full marks for 50 with no working. Error carried forward allowed for the answer mark if the addition was slipped but the division by 5 is shown. Do not credit median or range.

The scores fall steadily from 26 at 0.1 km to 15 at 1.5 km, rise slightly to 17 at 2.0 km, then fall to the lowest value of 11 at 2.5 km. The overall trend is a negative relationship, with one anomaly.

2 x 1 (tick) for each valid point, up to 2.
- General trend: environmental quality decreases / gets worse with distance from the town centre (1).
- Supporting data quoted, e.g. from 26 at 0.1 km to 11 at 2.5 km, or a difference of 15 (1).
- Anomaly identified with data: score rises at 2.0 km (17) compared with 1.5 km (15) (1).
The data mark requires a correct figure from the table. Accept a range of 14 to 16 for a difference stated between the extremes only if consistent with the table (the correct difference is 15). Do not credit a bare 'it gets lower' with no reference to distance or data for the data mark.

Choosing only friendly-looking people is biased sampling, and a single site and time (Saturday morning outside a coffee shop) means certain groups are over-represented, so conclusions cannot be generalised to everyone who uses the town centre.

2 marks: 1 for identifying a valid weakness and 1 (DEV) for a development explaining why this affects reliability. Full marks can be awarded for one well-developed explanation.
Valid ideas:
- Biased selection / not random (1), so some groups of people are missed and the sample is not representative (DEV).
- Small sample size of 20 (1), so anomalies have a large effect and results cannot be generalised (DEV).
- Only one site and time, Saturday morning (1), so people who visit on weekdays or evenings are missed (DEV).
Do not credit vague answers such as 'people might lie' or 'it was cold' without a link to reliability.

Order the data: 9, 10, 11, 12, 14, 15, 15, 16, 18, 20. There are ten values, so the median lies halfway between the 5th (14) and 6th (15) values: (14 + 15) / 2 = 14.5.

2 marks. 1 mark for method: data placed in correct order, or identifying 14 and 15 as the middle values. 1 mark for the correct answer of 14.5. Full marks for 14.5 with no working. Accept 14 or 15 for the method mark only if the middle position is clearly shown. Do not credit the mean (13.9) or range (11).

Read the two missing values from the table: 400 m = 33 and 500 m = 27. On the vertical axis (steps of 10), 33 lies just above the 30 line (about one third of the way to 40) and 27 lies just below the 30 line (about 7/10 of the way from 20 to 30). Draw a bar of the same width as the others at each position, rising from the horizontal axis to these heights. The completed graph shows a steady decrease in pedestrian numbers with distance from the town centre.

2 x 1 (tick) for each bar correctly plotted:
- 1 mark: bar for 400 m drawn to 33 (accept 32 to 34 on the scale).
- 1 mark: bar for 500 m drawn to 27 (accept 26 to 28 on the scale).

Both bars must be in the correct position on the horizontal axis, start from the axis, and be of similar width to the existing bars (bars may be ruled or neatly freehand; shading is not required).
Do not credit a bar drawn at the correct height but in the wrong position, or a line or point instead of a bar.
Do not credit bars whose heights have been swapped between the two sites.
If one bar is correct and the other incorrect, award 1 mark.

Overall fall: 148 - 22 = 126 people; 126 / 148 x 100 = about 85% decrease. Each site is lower than the previous one except Site 4 (119 vs 117), a minor anomaly, possibly caused by a bus stop or cafe nearby. The largest drop is between Sites 4 and 5 (43 people over 100 m), which may mark the edge of the main shopping area. The data therefore largely but not perfectly support the idea, based on one 5-minute count per site on one day. Improving reliability: repeat counts at several times of day and on different days, calculate means, count for longer, or use more pupils per site to reduce counting error.

Levels of response, AO3 (4 marks) and AO4 (2 marks).
Level 3 (5-6 marks): Thorough assessment using several accurate data points or calculations, recognises both the overall trend and the anomaly or the steepest fall, reaches a supported judgement on how far the data support the idea, and gives a developed, valid suggestion to improve reliability.
Level 2 (3-4 marks): Reasonable use of data to describe the trend, some attempt at a judgement, suggestion for reliability present but not developed.
Level 1 (1-2 marks): Basic, generic statement that footfall falls, little or no use of data, no judgement.
0 marks: no creditable response.
Indicative content (not exhaustive): overall decrease 148 to 22 (accept about 85%); anomaly at Site 4 (119 > 117); steepest fall Site 4 to 5 (43); limited sample of 8 sites and one 5-minute count; reliability - repeat counts at different times/days and calculate mean, more sites, same count duration.
Cap: if no suggestion for reliability is given, maximum Level 2 (4 marks). Do not credit a bare statement such as 'collect more data' without how or why.

Example: Enquiry 'How does river velocity change downstream?' at a UK river. Velocity was measured at 6 sites using a flow meter, three repeats per site, and a mean calculated. Means were plotted on a line graph against distance from source. The graph showed velocity rising from 0.2 m/s to 0.7 m/s, explained by the channel becoming larger and more efficient with less friction relative to volume. This answered the question well as the trend was clear, but one site had a boulder-strewn bed which gave an anomaly, and only six sites on one day limits confidence.

Levels of response, AO3 (3 marks) and AO4 (3 marks).
Level 3 (5-6 marks): Thorough, accurate explanation of a presentation and analysis technique applied to the candidate's own data, with developed geographical explanation of the pattern, and a balanced evaluation of how well it answered the enquiry question.
Level 2 (3-4 marks): Reasonable explanation of presentation and some analysis; evaluation is limited or partial.
Level 1 (1-2 marks): Basic description of data or method with little explanation or evaluation.
0 marks: no creditable response.
Indicative content: choice of graph/map/diagram and why suitable; calculations (mean, range); description of pattern with figures; explanation using theory (e.g. Bradshaw model, longshore drift, wave energy); anomalies; sample size, timing, accuracy of equipment; judgement on conclusion.
Cap: if the data is not from a physical enquiry or is not the candidate's own, maximum Level 1. Evaluation may be implicit. Do not credit generic textbook description with no link to the candidate's enquiry.

Difference in means: 5.2 - (-4.6) = 9.8. The ranges do not overlap (inner city maximum +1, suburb minimum +2), which strengthens the conclusion. Weaknesses: bi-polar scoring is subjective and differs between pupils (could be reduced by agreeing criteria or having several pupils score each site); five sites per area is small; first-five-streets is convenience sampling, which risks bias, whereas systematic or random sampling along a transect would be better; one day and time (e.g. rush hour affects traffic and noise score); inner city and suburbs are broad areas with variation. Judgement: supported but limited confidence.

Levels of response, AO3 (5 marks) and AO4 (3 marks).
Level 4 (7-8 marks): Comprehensive evaluation of both methods and conclusion; uses data from Fig. B accurately (e.g. 9.8 difference, ranges do not overlap); several developed weaknesses with improvements (subjectivity, sample size, sampling bias, timing); reaches a clear overall judgement on how far the conclusion is justified.
Level 3 (5-6 marks): Thorough evaluation, uses data, at least two developed methodological points, judgement present.
Level 2 (3-4 marks): Reasonable, some data use and some valid evaluation points, limited development or judgement.
Level 1 (1-2 marks): Basic, generic comments such as 'more sites would help', little use of data.
0 marks: no creditable response.
Indicative content: means and ranges; no overlap of ranges; subjectivity of scoring; small sample; convenience sampling vs random/systematic; single time of day; use of improvements; accept valid alternatives.
Note to markers: the ranges do not overlap (inner city maximum +1; suburb minimum +2). Accept 9.8 or 'about 10' for the mean difference. Do not credit a bare 'not enough time'.

The SPaG mark is awarded for the quality of written English and the use of geographical terminology, not for the geography itself. A strong answer is a short, well-organised report that:
- names the physical enquiry and the data collected (e.g. channel width, depth, velocity, beach profile, pebble size);
- evaluates one or two methods, e.g. a small sample size, human error in using a ranging pole or tape, or a missing anomaly check;
- suggests improvements, e.g. repeat readings, a larger sample, systematic sampling, or using the same equipment and person at each site;
- uses specialist terms accurately and spells them correctly.
Sample answer: 'My enquiry investigated how velocity changed downstream. I used a flow meter at six sites, but each reading was taken only once, so reliability was low. One anomaly, caused by a fallen branch, raised the mean at site four. To improve accuracy I would repeat each measurement three times and use a larger sample size with systematic sampling every 50 metres.'

SPaG: 3 marks. Mark only if the response makes an attempt at the task and relates to physical fieldwork.

High performance (3 marks): spelling and punctuation are consistently accurate; rules of grammar are used with control; meaning is clear throughout; a wide range of specialist terms is used accurately and appropriately (at least 4 correct terms).

Intermediate performance (2 marks): spelling and punctuation are generally accurate, with minor errors that do not hinder meaning; grammar is mostly controlled; a good range of specialist terms is used (2-3 correct terms).

Threshold performance (1 mark): spelling and punctuation are accurate in places; some control of grammar, and meaning is mostly clear; limited use of specialist terms (1 correct term).

0 marks: no response, a response not worthy of credit, or errors that severely limit meaning; no specialist terms.

Notes: Do not credit a bare list of terms with no sentence context. Do not penalise the candidate's choice of river, coastal or other physical enquiry. The geographical content of the answer is not itself marked here; only the quality of written English and terminology. Credit terms such as sample size, accuracy, reliability, anomaly, systematic sampling, mean, repeat readings, human error.