Key term
OCR A-Level Geography H481
Coastal Landscapes
Topic overviewThe coastal system: inputs, outputs and flows of energy and materialSediment cells, the sediment budget and the sources of coastal sedimentWinds, fetch and the generation of wavesConstructive and destructive waves, and how waves breakTides, tidal range and ocean currentsLithology, geological structure and the plan of the coastWeathering and mass movement on the coastMarine erosion, transport and depositionBays, headlands, cliffs and shore platformsGeos, blow holes, caves, arches, stacks and stumpsBeaches and the changing beach profileSpits, bars, tombolos and salt marshesHigh and low energy coastlines as characteristic landscapesEmergent coasts: raised beaches, marine terraces and abandoned cliffsSubmergent coasts: rias, fjords and shingle beachesCoastal management and its effect on the sediment budgetPorts, tourism and unintended change at the coast
Glaciated Landscapes
Topic overviewThe glacier system: inputs, stores, flows and outputsGlacier mass balance and the equilibrium lineClimate, latitude and altitude as controls on glaciationGeology, relief and aspect in glaciated landscapesFirn, glacier ice, valley glaciers and ice sheetsWarm-based and cold-based ice, and the mechanisms of glacier movementWeathering, mass movement and nivation in cold environmentsGlacial erosion and the marks it leaves on rockEntrainment, transport and deposition of glacial sedimentCorries, arêtes and pyramidal peaksGlacial troughs, hanging valleys and ribbon lakesMoraines, erratics, drumlins and till sheetsCharacteristic glaciated landscapes and how they change over timeGlacio-fluvial landforms of deglaciation: kames, eskers and outwash plainsPermafrost, patterned ground and pingosPeople in periglacial landscapes: resource extraction and thermokarstPeople in glaciated landscapes: dams, reservoirs and valley change
Dryland Landscapes
Topic overviewDryland landscape systems: inputs, stores, flows and outputsAridity, the water balance and the UNEP aridity indexRainfall, pressure belts and the global pattern of aridityRock type and structure in dryland landscapesRelief, aspect and desert microclimatesSediment supply and the dryland sediment budgetPolar drylands and the cold desertsHot deserts of the low and mid latitudesSemi-arid environments and the desert marginsWeathering and mass movement in dryland landscapesFluvial and aeolian processes in the desertWadis, canyons, pedestal rocks, ventifacts and desert pavementsBarchans, linear dunes, star dunes, alluvial fans and bajadasThe Mojave and the Sahara as desert landscape systemsInselbergs, pediments and relict landforms of past pluvialsFrost-shattered debris, nivation hollows and solifluction depositsWater supply, dams and landscape changeTourism, off-road vehicles and landscape change
Earth’s Life Support Systems
Topic overviewWater and carbon as the foundations of life on EarthOpen and closed systems, and the major global stores of water and carbonInputs and outputs of the water cycle: precipitation, snowmelt and evapotranspirationInputs and outputs of the carbon cycle, and the forms of chemical weatheringEvaporation, transpiration, condensation and the causes of rainfallInterception, runoff and catchment hydrologyPhotosynthesis, respiration, decomposition and combustion as carbon flowsNatural sequestration in oceans, vegetation, sediments and rockStores, flows and physical controls in the tropical rainforestDeforestation, farming and forest management in an Amazon drainage basinStores, flows and seasonal change in the Arctic tundraOil and gas development in the Arctic tundra, and its managementDynamic equilibrium, land use change and water extractionFossil fuel combustion, carbon sequestration and feedback loopsChange over time in the cycles, and the monitoring that records itLinks and interdependence between the water and carbon cyclesGlobal strategies to protect the carbon and water cycles
Changing Spaces; Making Places
Topic overviewThe characteristics that shape a place profileContrasting place profiles: Chelsea and BlackpoolPast and present connections, and the scales that embed a placeShifting flows of people, resources, money and ideasSpace, place and the effects of time-space compressionPerception, identity and emotional attachment to placeInformal representations of place in media and the artsFormal and statistical representations of placeMeasuring social inequality and its spatial patternsDeindustrialisation, globalisation and structural economic changeRecession, austerity and the government's role in inequalityLiving with inequality: Sparkbrook and Sutton ColdfieldPlayers driving economic change at different scalesThe Ruhr: a region reshaped by structural economic changePlacemaking and the marketing of places to investorsDesign, mixed use and community-led placemakingRebranding through reimaging and regenerationSalford Quays: from docks to MediaCityUK
Trade in the Contemporary World
Topic overviewMerchandise, services and capital flowsGlobal trade patterns: inter-regional and intra-regional flowsTrade, export value and human developmentTrade as a driver of growth, stability and developmentTrade inequalities, conflict and injusticeTransport, technology and the global supply chainMultinationals, outsourcing and the new international division of labourRegional trading blocs and the European UnionSouth–south trade and the growth of traded servicesIndia: trade patterns of an emerging economyThe United States: a core economy shaping world tradeEthiopia: trade on the periphery of the global system
Global Migration
Topic overviewThe global migrant population: size, composition and direction of flowInter-regional and intra-regional flows, and the world's major migration corridorsRemittances, the Human Development Index and the migration-development linkMigration as a driver of stability, growth and developmentInequality, conflict and injustice in the global migration systemEconomic globalisation and the emergence of new source and host areasYoung workers, women migrants and the growth of South-South movementConflict, persecution and the world's refugee movementsNational immigration and emigration policy, and how it is changingMexico: an emerging economy shaped by a migration corridorThe United Kingdom: an advanced country driving change in the migration systemNepal: a low-income country with little leverage over its migration
Human Rights
Topic overviewThe idea of human rights and its legal foundationsNorms, intervention and geopoliticsForced labour and modern slaveryMaternal mortality and access to safe childbirthCapital punishment and where it persistsPatterns of gender inequality: schooling, reproductive health and workWomen's rights in IndiaHuman rights abuse as a cause and a consequence of conflictInstitutions, treaties and laws that protect human rightsGlobal governance of human rights in eastern DR CongoShort-term relief and long-term change in DR Congo
Power and Borders
Topic overviewStates, nations and the sovereign control of territoryNorms, intervention and geopoliticsContested borders and the legacy of colonial boundariesTransnational corporations and economic sovereigntyTrading blocs, supranational institutions and pooled sovereigntyEthnic dominance, minority marginalisation and separatismUkraine: sovereignty and territorial integrity under challengeResources, conflict and the causes of geopolitical instabilityGlobal institutions, international law and the flows that carry interventionSouth Sudan: governing a conflict from global to localShort-term and long-term outcomes of intervention for people and placesThe Democratic Republic of the Congo: global governance in an LIDC
Climate Change
Topic overviewReconstructing past climates from natural archivesIcehouse and greenhouse Earth, from Cenozoic cooling to the HoloceneContinental drift and volcanic activity as drivers of climateMilankovitch cycles and changes in solar outputThe natural greenhouse effect and the atmosphere's greenhouse gasesWarming of the surface, atmosphere and oceans since the late 19th centuryRetreating ice, shrinking snow cover and rising sea levelWhy greenhouse gas emissions have risen since the pre-industrial eraThe changing global balance of emissions, from an AC to an EDCThe enhanced greenhouse effect and the global energy balanceThe evolution of the global warming debateGovernments, international organisations and the media in the climate debateClimate models, the carbon cycle and feedbackFuture emission scenarios and projected temperature and sea level riseImpacts on ecosystems, health and extreme weatherThe vulnerability of people and environments to climate changeMitigation through energy efficiency, fuel shifts and low-carbon energyCarbon capture and storage, forestry strategies and geoengineeringRetreat, accommodation and protection as adaptationAdapted homes, cities, transport and economiesContrasting countries: impacts, opportunities and the challenges of respondingThe IPCC, international agreements and policy from global to local
Disease Dilemmas
Topic overviewWays of classifying disease, and the epidemic to pandemic scaleMapping the burden of malaria, HIV, tuberculosis, diabetes and heart diseaseDisease diffusion, the Hägerstrand model and the barriers that slow itTemperature, rainfall, relief and water supply as controls on diseaseMosquitoes, vectors and the seasonal rhythm of outbreaksClimate change, emerging infections and diseases that jump from animalsCholera in Haiti after the 2010 earthquakeRising living standards and the epidemiological transitionDiseases of poverty and diseases of affluenceAir pollution and lung cancer in ChinaMalaria in Nigeria: from causes to controlCardiovascular disease in the United KingdomThe World Health Organization and the surveillance of global outbreaksMédecins Sans Frontières and the West African Ebola epidemicPhysical barriers to treatment and the fight against HIV and AIDSMedicinal plants, their growing conditions and the trade that threatens themPharmaceutical transnationals and the global flow of medicinesEradication campaigns, grassroots education and the role of women
Exploring Oceans
Topic overviewThe size and spread of the world's oceansThe shape of the sea floor, from shelf to trenchSalinity and temperature through the water columnSurface currents and the great ocean gyresThe North Atlantic conveyor, from Gulf Stream to deep return flowLight, warmth and nutrients as limits on ocean lifeFood webs in the inter-tidal zone and the deep seaHarvesting Southern Ocean krillWhaling, stakeholder conflict and resource thresholdsOcean energy: oil, gas, waves and tidesMining the deep sea bed for metalsThe global commons, maritime zones and ocean governanceThe major sources of marine pollutionThe Deepwater Horizon oil spill and its aftermathDrifting plastic and the North Pacific garbage patchOcean acidification, warming seas and coral bleachingRising sea level and low-lying island communitiesSea ice, the albedo feedback and irreversible thresholdsThe changing Arctic: peoples, politics and new sea routesShipping lanes, container ships and seaborne tradeNaval power and contested seasPiracy and migration by sea
Future of Food
Topic overviewFood security and its three pillarsMeasuring hunger: undernourishment data and food security indicesShifting patterns of food security between and within countriesClimate, soil, water and relief as controls on where food can be grownThe journey of food from farm to plate, and the waste it leavesTypes of farming: intensive, extensive, subsistence and commercialGlobalisation, rising demand and global tastesThe issues and opportunities of a globalised food industryLand ownership, competition and land grabbingMalthus, Boserup and the population–resource debateYemen: conflict, aridity and the collapse of food accessVulnerable people and the pinchpoints in global food distributionDesertification and the drylands of the SahelExtreme weather, water scarcity and tectonic shocks to food productionInuit hunting and food security in the ArcticSalinisation, deforestation and agrochemical pollution from farmingThe Aral Sea: a landscape remade by irrigationHealth effects of hunger, over-nutrition and agrochemical exposureMalawi and the United States: contrasting experiences of food insecurityTrade policy, the World Trade Organization and appropriate aidAgribusiness, food TNCs, supermarkets and fair tradeFrom emergency relief to capacity building and system redesign
Hazardous Earth
Topic overviewThe Earth's internal structure and the global pattern of platesContinental drift and the evidence from fossils, rocks and ancient glaciationsSea-floor spreading, palaeomagnetism and the age of the ocean floorDivergent boundaries and the landforms of the mid-ocean ridgesSubduction at oceanic-continental and oceanic-oceanic boundariesContinental collision and conservative boundariesMagma chemistry, viscosity and explosive volcanism at subduction zonesEffusive eruptions, shield volcanoes and hot-spot volcanismVolcano size and shape, super-volcanoes and the Volcanic Explosivity IndexLava flows, pyroclastic flows and volcanic gasesTephra, ashfall, lahars and volcanic tsunamisEarthquake focus, depth and the seismic waves releasedMeasuring earthquakes: Richter, moment magnitude and Mercalli intensityFault scarps, rift valleys and the landscapes faulting createsGround shaking, ground displacement and liquefactionEarthquake-triggered landslides, avalanches and floodingTsunamis from sea-bed uplift and underwater landslidesWhy people choose to live in tectonically active placesThe impacts of volcanic eruptions in countries at contrasting levels of developmentThe impacts of earthquakes in countries at contrasting levels of developmentPredicting, monitoring and managing volcanic hazardsLand-use zoning, building design and managing earthquake riskChanging risk over time and the disaster risk equationThe Park model of disaster response
Geographical Skills
Topic overviewGeographical data, its types and the ethics of using itCollecting data: sampling, measurement error and digital devicesQualitative methods, sources and drawing conclusionsMeasures of central tendency and dispersionCorrelation, lines of best fit and Spearman's rankSignificance tests: chi-squared, Mann-Whitney U and the t-testClimate graphs, maps and graphical techniques
Dryland Landscapes
- 18 subtopics
- 45 things to know
- Component 01
What Dryland Landscapes covers
Dryland Landscapes is examined in Component 01, Physical systems. It covers drylands as systems of inputs, stores, flows and outputs; aridity, the water balance and the UNEP aridity index; the pressure belts, ocean currents and relief behind the global pattern of aridity; rock type, structure, aspect and desert microclimates; and the dryland sediment budget. It also covers polar, hot and semi-arid drylands; weathering, mass movement and fluvial and aeolian processes; landforms from wadis, canyons, ventifacts and desert pavements to barchans, linear and star dunes, alluvial fans and bajadas; the Mojave and the Sahara as desert landscape systems; inselbergs, pediments and the relict landforms of past pluvial and periglacial climates; and how water supply, dams, tourism and off-road vehicles change dryland landscapes.
The 18 subtopics
Each one has its own page.
- Dryland landscape systems: inputs, stores, flows and outputsRecall questions on the dryland as an open system: its energy and material inputs, outputs and sediment stores, why its water store is small, geomorphic processes, positive and negative feedback, dynamic equilibrium, and why drylands respond so quickly to change.Open →
- Aridity, the water balance and the UNEP aridity indexRecall questions on aridity and potential evapotranspiration, the UNEP aridity index and its hyper-arid, arid, semi-arid and dry sub-humid classes, the share of land that is dryland, worked index and water balance calculations, aridity versus drought, and the limits of the index.Open →
- Rainfall, pressure belts and the global pattern of aridityRecall questions on desert rainfall and its unreliability, the Hadley cell and subtropical high pressure, the latitude of the hot deserts, continentality, rain shadows and the Patagonian Desert, cold currents off the Namib and Atacama, and high-altitude drylands.Open →
- Rock type and structure in dryland landscapesRecall questions on lithology and rock resistance in deserts, mesas and buttes in Monument Valley, permeability, joints and bedding planes, calcrete, gypcrete and silcrete duricrusts, sandstone as a dune source, dipping strata, and faulting in the Basin and Range Province.Open →
- Relief, aspect and desert microclimatesRecall questions on desert microclimates, how aspect and slope angle change temperature, moisture, vegetation, weathering and runoff, orographic rain on the Tibesti Mountains, albedo, the large daily temperature range and the world's highest recorded temperature, canyon microclimates, and dew.Open →
- Sediment supply and the dryland sediment budgetRecall questions on the dryland sediment budget and a worked storage calculation, sediment sources, supply versus availability, the water table and aeolian transport, dune fields fed by dry lake beds and the Kelso Dunes, Saharan dust export, sediment sinks, and measuring a budget in the field.Open →
- Polar drylands and the cold desertsRecall questions on why Antarctica is a desert, dry polar air, the McMurdo Dry Valleys, katabatic winds and sublimation, polar dryland landforms and weathering, permafrost, aeolian processes, and why polar drylands are sensitive to warming.Open →
- Hot deserts of the low and mid latitudesRecall questions on where low-latitude and mid-latitude deserts lie, the Sahara, the Gobi and the Great Basin, their temperature regimes, sand seas or ergs, hamada and reg surfaces, and desert vegetation and soils.Open →
- Semi-arid environments and the desert marginsRecall questions on semi-arid vegetation and rainfall seasonality, the Sahel, soil erosion on semi-arid land, desertification and overgrazing, how vegetation loss reinforces dryness, dune reactivation and the Kalahari linear dunes, rainfall variability and farming, and playas.Open →
- Weathering and mass movement in dryland landscapesRecall questions on salt weathering and sodium sulfate, tafoni, insolation weathering and the moisture debate, freeze-thaw, hydration and oxidation in deserts, desert varnish, and rockfalls, debris flows and dry ravel on desert slopes.Open →
- Fluvial and aeolian processes in the desertRecall questions on desert runoff, ephemeral streams, exotic rivers and endoreic drainage, flash flood hydrographs and transmission losses, sediment loads, deflation and the Qattara Depression, wind abrasion, saltation, surface creep and suspension, and the wind speed needed to move sand.Open →
- Wadis, canyons, pedestal rocks, ventifacts and desert pavementsRecall questions on how wadis and canyons form and stay steep, the Grand Canyon and the Colorado River, pedestal rocks and the processes that undercut them, ventifacts and dreikanters, and the competing explanations for desert pavements.Open →
- Barchans, linear dunes, star dunes, alluvial fans and bajadasRecall questions on the conditions, shape and migration of barchans, slip faces, linear dunes and star dunes, alluvial fans and their sorting, bajadas, and fieldwork methods for measuring dune shape, barchan migration, fan sorting and geo-spatial mapping.Open →
- The Mojave and the Sahara as desert landscape systemsRecall questions on the Mojave as a mid-latitude, transitional desert with winter rain, its Basin and Range landforms, Death Valley and Lake Manly, the Mojave River and Kelso dunes, and the Sahara's flash floods, Tibesti and Ahaggar streams, African Humid Period and Lake Mega-Chad.Open →
- Inselbergs, pediments and relict landforms of past pluvialsRecall questions on pluvial periods and their causes, evidence of past pluvial climates, inselbergs such as Uluru and the competing explanations for them, pediments, their gradient and formation by sheetflooding, and how inselbergs and pediments change under present and future climates.Open →
- Frost-shattered debris, nivation hollows and solifluction depositsRecall questions on relict periglacial landforms in warm deserts, frost shattering and recognising its debris, relict scree slopes, nivation hollows and their aspect, solifluction and its deposits, and how warming affects periglacial features in drylands and polar deserts.Open →
- Water supply, dams and landscape changeRecall questions on water demand and drought in drylands, the over-allocated Colorado River, Glen Canyon Dam and sediment trapping, hungry water, Grand Canyon sandbars and controlled flood releases, the Colorado delta, effects on alluvial fans and wadis, groundwater abstraction, and the Aral Sea.Open →
- Tourism, off-road vehicles and landscape changeRecall questions on desert tourism, cryptobiotic crust and its functions, how off-road vehicles increase wind erosion, dune activity, runoff and gullying around Moab in Utah, loess and dust carried to distant snowpack, management of recreational damage, and slow dryland recovery.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
How does aspect affect slope conditions in a northern hemisphere desert?
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Why does sediment availability matter as much as sediment supply?
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How can a high water table limit aeolian transport?
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How does salt weathering break up desert rock?
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How is a wadi both deepened and widened?
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What is a canyon?
Process
Explain two processes that combine to undercut a pedestal rock.
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Describe the form of a linear dune.
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Why does Death Valley have no outlet to the sea?
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Give three kinds of evidence for a former pluvial climate in a desert.
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How does deep weathering during a pluvial period help to create an inselberg?
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How can a pediment be distinguished from an alluvial fan in the field?
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Why do some warm deserts contain landforms made by frost?
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Why does the Colorado usually fail to reach the sea?
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Name three energy inputs into a dryland landscape system.
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State the aridity index value below which an area is classed as hyper-arid.
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Define lithology as a control on dryland landforms
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Which is the largest ice-free area of the Antarctic continent?
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Which is the world's largest hot desert, and roughly what area does it cover?
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Why is rainfall seasonality so important in semi-arid areas?
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Why do deserts produce so much runoff from so little rain?
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What is cryptobiotic crust?
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Identify three material inputs to a dryland landscape system.
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Which aridity index values define an arid environment?
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How much precipitation does a true desert typically receive in a year?
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Why do horizontally bedded resistant strata produce mesas and buttes?
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Why is vegetation often denser on a pole-facing desert slope?
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Why do the McMurdo Dry Valleys contain almost no ice?
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Describe the temperature regime of a low-latitude desert.
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What is the name of the semi-arid belt along the southern edge of the Sahara?
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Define weathering in a dryland landscape
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What is an exotic river? Give one example.
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What conditions produce a barchan dune?
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How does the Basin and Range structure of the Mojave control its landforms?
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How does frost shattering break rock apart?
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Why is water demand so often greater than supply in a dryland?
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How does off-road vehicle use increase wind erosion?
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What are the main outputs from a dryland landscape system?
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Which aridity index values define a semi-arid environment?
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Why does the descending limb of the Hadley cell create arid conditions?
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Name a desert landscape famous for mesas and buttes cut in horizontal sandstone.
Process
How does aspect alter the weathering processes operating on a desert slope?
Key term
State the relationship used in a sediment budget calculation.
Key term
Define the term katabatic wind.
Take Dryland Landscapes further
The same content, four other ways.
Commonly confused
Pairs that lose marks when they are blurred together.
Aridity vs Drought
Aridity: a permanent climatic condition in which a place receives very little precipitation year after year. Drought: a temporary spell in which rainfall falls well below what a place normally receives.
Sediment supply vs Sediment availability
Sediment supply: the total quantity of loose material that weathering, rivers and the wind have delivered to an area. Sediment availability: the share of that loose material which is dry, bare and unbound, so the wind can actually lift it.
Pediment vs Alluvial fan
Pediment: a gently sloping surface cut across bedrock at the foot of a mountain front, carrying only a thin veneer of debris. Alluvial fan: a thick, cone-shaped pile of material dropped where a stream leaves a mountain front and loses its power.
Questions from this topic
Each one with the model answer underneath.
- 1
What is meant by describing a dryland as an open system?
Model answer
It is an area of the Earth's surface that exchanges both energy and matter with its surroundings, so material and energy can cross its boundaries.
- 2
Name three energy inputs into a dryland landscape system.
Model answer
The main energy inputs are solar radiation, the kinetic energy of the wind, and the potential energy held by sediment resting on slopes.
- 3
Identify three material inputs to a dryland landscape system.
Model answer
Material inputs include precipitation, weathered bedrock and regolith produced in place, and sediment blown or washed in from outside the area.
- 4
What are the main outputs from a dryland landscape system?
Model answer
The main outputs are water lost by evaporation and transpiration, dust exported by the wind, and sediment carried away by ephemeral or exotic rivers.
- 5
Give four sediment stores found in a desert landscape.
Model answer
Dune fields, alluvial fans, playa deposits and the regolith mantling hillslopes are all sediment stores.
- 6
Why is the water store in a dryland system usually very small?
Model answer
Precipitation is low and infrequent while potential evaporation is extremely high, so most water leaves the system almost at once and little is retained in soil or channels.
What is inside Levo
Six ways to work the same material.
Dryland Landscapes revision questions
- What does Dryland Landscapes cover in OCR A-Level Geography?
- 18 subtopics: dryland landscape systems: inputs, stores, flows and outputs, aridity, the water balance and the unep aridity index, rainfall, pressure belts and the global pattern of aridity, rock type and structure in dryland landscapes, relief, aspect and desert microclimates, sediment supply and the dryland sediment budget, polar drylands and the cold deserts, hot deserts of the low and mid latitudes, semi-arid environments and the desert margins, weathering and mass movement in dryland landscapes, fluvial and aeolian processes in the desert, wadis, canyons, pedestal rocks, ventifacts and desert pavements, barchans, linear dunes, star dunes, alluvial fans and bajadas, the mojave and the sahara as desert landscape systems, inselbergs, pediments and relict landforms of past pluvials, frost-shattered debris, nivation hollows and solifluction deposits, water supply, dams and landscape change and tourism, off-road vehicles and landscape change. Each one has its own page with questions and model answers.
- How is Dryland Landscapes organised?
- By the OCR H481 specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Dryland Landscapes, on a schedule.
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