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GCSE
GEOGRAPHY
REVISION
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UNIT 1
EDEXCEL B
Unit 1: Dynamic Planet
Revision Guide.
Unit 1 is worth 25% of your final GSCE Geography Grade.
You will have to answer a range of questions (maximum 6 mark answers) on 6 topics (see below).
Use the information below help you revise. Ensure you start your revision early to stop any panic
nearer the time.
In Section B (see grid above), you will ONLY answer the questions on Coastal Change and
in Section C ONLY Oceans on the Edge.
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Unit 1: Dynamic Planet
 Battle For the Biosphere:
What you need to know:
Check list
What 3 things make up the biosphere? Lithosphere (land), hydrosphere(water) and
atmosphere (air).
What is a biome.?
Be able to describe the location of tropical rainforests, deserts, polar and savannah
grassland and why they are found there.
What factors affect the distribution of biomes? Latitude, altitude, continentality (is it
close to a coast or inland), geology.
What is a ‘service’ that humans get from the biosphere and be able to give
examples.
What is a ‘good’ that humans get from the biosphere and be able to give examples.
How do humans degrade the biosphere?
How can the biosphere be conserved? Biosphere conservation, CITES, National
Parks, World Heritage Sites and sustainable management. Know briefly how each
works.
Case study – Korup National Park.
 Climate and Change
What you need to know:
What is climate change?
What will graphs show about climate in the past?
What are the natural causes of climate change? Orbital changes, solar
output, volcanic activity.
How can you find out what the climate was like in the past? (Apart from
written records) Ice cores, tree ring dating, paintings, diaries etc…
Natural climate change has affected people and ecosystems, give
examples. E.g. Greenland’s Vikings, farming etc…
Give a couple of examples of things that are extinct due to natural climate
change.
What is the greenhouse effect and what are the GHGs? CO2, methane,
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Check list
Unit 1: Dynamic Planet
nitrous oxide and water vapour.
What has happened to the climate since the 19th Century and why?
Give some examples / evidence of climate change? E.g. drought etc…
Summarise your Bangladesh case study.
What is the ‘tipping point’?
How can we reduce climate change on a local, regional, national and global
scale?
Is global warming all bad?
What is the ‘Stern Review’?
Why do some people not believe in global warming?
 Restless Earth:
What you need to know:
Check list
Earth structure – inner core, outer core, mantle and crust.
The two types of crust and which is heavier – oceanic and continental.
The four plate boundaries; conservative, constructive, destructive and
collision.
Convection currents – what they are, where they occur and how they
cause plates to move.
The two types of volcanoes and examples of each.
The two types of earthquakes and examples.
The impact of volcanoes and earthquakes.
How to prepare for earthquakes and volcanoes.
 Water World:
What you need to know:
What happens in the hydrological cycle and understand that it links the
atmosphere, lithosphere and biosphere.
Changes to the hydrological cycle can affect both human and
ecosystem health.
Unreliable water supply and the impact on humans case study; Australia
or Sahel.
Impact of climate change on the hydrological cycle and ecosystems.
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Check list
Unit 1: Dynamic Planet
Mini case-studies; Australia, Maldives, Arctic, Ethiopia, Africa,
Caribbean and Bangladesh.
Know examples of what can threaten a healthy hydrological cycle. E.g.
pollution, farming, industry; mining, sewage, transport etc…
Know example of how human interference can disrupt water supply e.g.
deforestation, over-abstraction of groundwater and reservoir and dam
construction.
Know the costs (negatives) and benefits of a large scale water
management scheme; The Colorado River.
Understand what intermediate technology solutions are and an
example; Afridev in Tanzania.
 Coastal Change and Conflict:
What you need to know:
How and why do coasts vary – what are they used for?
What is geology and how does it affect the coast?
(resistant/non-resistant rock; E Yorkshire vs Land’s End;
discordant/concordant)
Physical processes along the coast (E  T  D); inc. wave types
Landforms of erosion (Headlands and Bays, Stacks and stumps and wavecut-notch).
Transportation along the coast (long shore drift)
Landforms of deposition (Spit, Tombolo and Bar)
Coastal defences – what are they? Pro’s & con’s and what do: hard and soft
engineering mean and ‘traditional’ and ‘more modern’ approaches mean.
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Check list
Unit 1: Dynamic Planet
 Oceans on the Edge:
What you need to know:
Know the global pattern of human use of a marine ecosystem;
mangroves swamps.
Understand the global pattern of threats to this ecosystem due to human
activities.
Know the processes that disrupt marine food webs e.g. over-fishing, and
cause nutrient cycles to be disrupted e.g. eutrophification and siltation.
Understand the role of climate change in adding additional stress to
threatened marine ecosystems. E.g. bleaching, warming oceans or sea
level rise.
Using a local-scale, named case study to investigate the growing
localised pressures on a named marine ecosystem.
Understand that different local groups may have different opinions on
how to manage this area and this can cause conflict.
Assess two local case studies of marine management.
Assess the global actions to maintain ocean health.
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Check list
Unit 1: Dynamic Planet
UNIT 1 : DYNAMIC PLANET
Atmosphere
Hydrosphere
Biosphere
Geosphere
The layers of gases/air around us.
The layer of water.
The very thin layer of living things on the crust.
The rocks of the crust and deeper towards the core.
How are we damaging each of the spheres?
Atmosphere  releasing CO2 into.
Hydrosphere  using too much water in some areas
Biosphere  deforestation (chopping down the trees)  animals extinct.
Geosphere  using up fossil fuels
The layers of the earth…
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The lithosphere (which is solid) is split into tectonic plates.
These move slowly (2-5cm/yr) on top of a layer called the asthenosphere (which
is like porridge)
CONTINENTAL CRUST = land, low density, thick.
OCEANIC CRUST = under the oceans, thin, dense.
Meteorites give us a clue as to what the core is like.
How do we know that the inside of the earth is hot?
 lava from volcanoes
 hot springs, geysers
Geothermal heat…
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Heat from the inside of the earth. Produced by the radioactive decay of
uranium etc in the core and mantle.
As heat rises from the core it creates convection currents in the liquid outer
core and mantle. These convection currents move the tectonic plates on top of
them.
PLUMES = where heat moves to the surface e.g. hotspots like Hawaii.
The magnetosphere….
The earth is surrounded by an invisible magnetic field –made by the outer core –
protects the earth from harmful radiation from space/the sun.
Pangea…
The continents were once all joined together – Pangea. How do we know this? Identical
fossils and rocks have been found in western Africa and Eastern South America for
example.
Today the lithosphere is split into 15 tectonic plates. Where 2 plates meet together =
plate boundary.
Constructive plate boundary…
Where two oceanic plates are moving apart from each
other.
 New oceanic crust is forming constantly in the gap
created.
 The magma is injected between the two plates. As it
cools it forms new oceanic crust.
 The magma is runny. Shallow sided volcanoes form.
HAZARDS:
Convection currents from the
 Small earthquakes are formed by friction as the plates tear apart.
mantle bring magma towards
 Volcanoes that are not very explosive/dangerous.
the surface. Magma is forced
Examples are Iceland – the Mid Atlantic Ridge
between the plates, cools and

forms new oceanic crust.
Destructive plate boundary…
Where an oceanic plate meets a continental plate.
They are moving towards each other.
 The denser oceanic plate is subducted beneath the
less dense continental plate.
HAZARDS:
 very destructive earthquakes
 tsunami
 very explosive, destructive volcanoes which cool to

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Unit 1: Dynamic Planet
be steep sided.
Examples are Andes mountains, Peru, Chile.
Conservative plate boundary…

Formed where two plates are sliding past each other.
HAZARDS:
 destructive earthquakes
 small earth tremors daily.
 no volcanoes
Example is San Andreas Fault, California
Collision Zone
A type of destructive boundary where two
continental plates move towards each other. As
they meet they push upwards forming mountain
ranges e.g. Himalayas.
HAZARDS:
 destructive earthquakes
 landslides  volcanoes are rare
Volcanic Explosivity Index (VEI)
Measures the destructive power of a volcano on a scale from 1 to 8.
Volcanic Hazards:
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Pyroclastic flows – deadly clouds of hot ash and gas.
Landslides
Lahars – volcanic mudslides
Lava flows
Ash builds up on the roofs of houses  buildings collapse.
Acid rain is created.
NAMED EXAMPLE: Sakurajima,
Japan
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Stratovolcano/ composite volcano (steep sided)
Destructive plate boundary
 Can erupt 200 times a year.
ADVANTAGES OF THE VOLCANO
 40% of the land is fertile, volcanic
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DISADVANTAGES OF THE VOLCANO
 7000 people live at the base (are
Unit 1: Dynamic Planet
soil  can grow rice and tea.
vulnerable).
Hot springs are a tourist
 There are lots of urban areas
attraction.
around the base.
 Sheltered bay is good for the
 The volcano hurls bombs of lava.
fishing industry.
 Pyroclastic flows and ash erupting.
Managing the threat:
 Japan is a developed country so has money…..
 MONITORING AND PREDICTION
 Aircraft monitor the amount of gas being given off.
 Tiltmeter detects swelling of magma in the rocks.
 Boreholes measure the temperature of the water.
 Hotsprings are monitored
 Seismometers monitor earthquake activity.
 PROTECTION
 Concrete shelters protect people from bombs/ash.
 Concrete lahar channels divert dangerous mudflows.
 EVACUATION
 Evacuation routes clearly sign posted.
 Evacuation drills.

Why are people in developing countries at greater risk
from tectonic hazards than people in developed countries?
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More live in risky conditions – no where else for them to live.
Can’t afford safe, well built houses  they collapse easily
Don’t have insurance
Governments don’t have the money to provide aid.
Poor communications – no warning or evacuation.
NAMED EXAMPLE: MOUNT
NYIRAGONGO, DEMOCRATIC REPUBLIC
OF CONGO, AFRICA
African rift valley
Constructive boundary
2002 hot and runny lava poured out. A river of lava 1000m wide flowed 20km
into the city of Goma.
 14 villages destroyed
 100 died – due to poisonous gas and trapped in the lava flow.
 12 500 homes destroyed
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Was predicted – 400 000 were evacuated
Refugees created (people forced to move due to natural hazards or war)
Unit 1: Dynamic Planet
AID AND RELIEF EFFORT ( help given by organisations/countries to help those
facing an emergency).
 United Nations sent 260 tonnes of food.
 UK TV appeal
 Governments around the world gave $35 million
 Emergency measles vaccinations by the World Health Organisation.
 most fled with nothing
 it was months before they could start rebuilding.
EARTHQUAKES can’t be predicted.
Underground plates try to push past each other– builds up pressure – suddenly released
along faults (cracks in the crust). Energy is sent out in all directions.
Magnitude = power of the earthquake
Seismometer measures the power on the richter scale
NAMED EXAMPLE:Niigata, 2007
AND Kobe 1995, both japan, how
different?
Both earthquakes were the same magnitude but…
Niigata, 2007, Japan
Kobe, 1995, Japan
 City of 90 000 – low population
 City of 1.1 million ( high population
density
density)
 11 died
 5000 died
 1000 injured
 26 000 injured
 Epicentre was offshore (out to sea)
 Soft ground made the shaking
so less shaking of the land.
worse
 6pm. People were alert and
 6am so people asleep and confused.
remembered their drills.
Long term planning…
There is a 70% chance of a huge earthquake hitting Tokyo. No way to predict it so….
 Earthquake drills
 Emergency services practice rescuing people
 People keep emergency kits at home – water, torch, radio, food.
BUILDINGS…
 Strong, double glazed windows – stop the glass from shattering.
Shock absorbers
 Strong steel frame
Cross bracing
Very deep foundation
Earthquakes in the developing world…
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11
Very high death tolls
Unit 1: Dynamic Planet
NAMED EXAMPLE: SICHUAN,
Central china 2008
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8.0 on the Richter scale
Collision zone where the Indian and Eurasian plates are colliding.
No warning
PRIMARY EFFECTS (Caused instantly by the earthquake)
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70 000 died
400 000 injured
5 million made homeless
$75 billion damage
SECONDARY EFFECTS (in the days and weeks following the earthquake)
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Lots of aftershocks  buildings collapse
LOCAL RESPONSES:
 Prime minister flew in
 50 000 soldiers helped dig for survivors
 Helicopters used to reach the isolated
 $1.5 billion aid from the Chinese people
INTERNATIONAL RESPONSES:
 Some countries sent money – UK $2 million
 Finland sent 8000 tents
 Indonesia sent medicines
 Rescue teams from Russia and Hong Kong
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Unit 1: Dynamic Planet
UNIT 2: CLIMATE AND CHANGE
WEATHER = short term, day to day changes in the atmosphere.
CLIMATE = the average weather conditions over 30 years.
How do we know climate was different in the past?
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Fossils of animals and plants that no longer live in the UK.
Landforms left by glaciers
Samples from ice sheets in Antarctica. Ice sheets are made up of layers of ice,
a layer for each year. Trapped in the ice sheets are air bubbles. Climatologists
study the CO2 levels to reconstruct past climates.
INTERGLACIALS = warm periods
GLACIALS = cold periods  ice ages  ice sheets 400-3000m thick extended across
the northern hemisphere.
How do we know climate has changed in the more recent
past?
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Old photos, paintings
Diaries
Newspapers
Recorded dates of blossom and migration of birds.
Theories used to explain why climate has changed in the
past (Natural events)....
1.
2.
3.
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ERUPTION THEORY – very large and explosive volcanic eruptions change
earth’s climate. Ash and gas spread around the stratosphere and stop
sunlight reaching the earth’s surface  cools the earth. Example is Mt
Pinatubo, 1991, Philippines – reduced global sunlight by 10% and cooled the
earth 0.5 degrees for a year.
SUNSPOT THEORY – black areas on the sun’s surface. Some times there
are more then they disappear. Spots mean greater activity and more solar
energy being sent towards the earth  warmer.
ORBITAL THEORY/MILANKOVITH CYCLES – Changes in the way the earth
orbits the sun from circular to ellipse alters the amount of sunlight the
earth receives.
Unit 1: Dynamic Planet
NAMED EXAMPLE: the little ice
age
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Greenland Vikings ran out of food and died as temperatures fell.
In England there were ‘frost fairs’ on the river Thames when it froze.
Crops failed
‘Great famine’
Farmers died of hunger
Glaciers in the Alps grew and destroyed villages
They had to change their crops from wheat to potatoes
Ecosystems – where plants and animals interact with each other and their
environment in order to survive. Can be small e.g. pond or large e.g. Tropical Rainforest.
How were ecosystems affected by climate change in the
past?
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The dinosaur extinction was possibly caused by a massive asteroid hitting
Mexico and a huge volcano in India combining  dust, ash, gas into the
stratosphere  blocks the sun  cools the climate  plants don’t grow 
dinosaurs have no food……..knock on effect through the food chain.
Megafauna extinction – big animals like the woolly mammoth. The climate was
warming so they had to find new areas to live where the climate suited them.
This disrupted food chains. Humans also hunted them to extinction.
How is our atmosphere being changed by human activity?
Greenhouse gases (CO2 from the burning of fossil fuels, deforestation, Methane
from paddy fields and cattle, Nitrous oxide from aircraft engines and
fertilisers) trap heat from leaving the atmosphere and re-radiate that heat
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Unit 1: Dynamic Planet
back down to earth. The greater the concentration of greenhouse gases, the
more heat is trapped and the warmer earth becomes.
We need the NATURAL greenhouse effect – it makes the planet 16 degrees
warmer. Without it the earth would be too cold for us to survive.
The extra greenhouse gases produces by humans  burning fossil fuels  power
stations, transport, industry, homes.
Most greenhouse gases are produced by developed countries – the EU, USA,
Japan.
The average person in the developing world
the developed world
produces 1 tonne of CO2.
of CO2.
The average person in
produces 10-25 tonnes
We are worried about increasing emissions. Issues we
need to think about:
 how can we decrease emissions in the developed world.
 how can we persuade developing countries e.g. China, India to slow their CO2
emissions.
 how do we protect vulnerable people from the impacts of climate change?
GLOBAL WARMING = a warming of the earth’s temperatures caused by the
ENHANCED greenhouse effect (human’s have polluted the atmosphere so it is
working more strongly).
 Global temperatures increase.
 sea levels rise  THERMAL EXPANSION (water droplets expand as warm)
and glaciers and ice sheets melt.
What evidence is there of Global Warming happening?
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19 out of 20 warmest years on record since 1980.
Sea ice in the Arctic shrank.
90% glaciers shrinking.
Scientists disagree – are human actions the main cause of global warming OR is it
mostly natural??
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Unit 1: Dynamic Planet
Predicting future Global Warming is hard….as we don’t
know:
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What the future population will be.
If we will continue to use fossil fuels or change to cleaner fuels e.g. solar, wind
power…
If we will change our lifestyles  recycle  use public transport etc.
How might the UK be affected by Global Warming?
1. Likely to be WARMER:
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2.
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COSTS
Summer drought and water
shortages, especially in the south.
More illnesses e.g. sunstroke, skin
cancer.
Roads melt, railway lines buckle.
Farmers change crops to those that
need less water and more sun.
Extinctions of some plants and
animals as it gets too hot.
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BENEFITS
Winter heating costs and the costs
of gritting the roads fall.
Tourism increases – good for the
economy.
Fewer deaths in winter especially
the elderly from the cold.
More land can be farmed at higher
altitudes.
SEA LEVEL rise
Low lying coasts could flood
Greater erosion e.g. Holderness
Sea defences and flood barriers would cost £millions.
3. More EXTREME WEATHER
 Heatwaves
 Floods
 Storms
Extreme weather is hard to predict and costly.
The Stern Review 2005
We should spend 2% our GDP now, reducing pollution OR the effects of global warming
could decrease our GDP by 20%. ‘Spend now or pay later’.
What can we do?
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Decrease fossil fuel use.
Switch to ‘green energy’ – wind, solar, tidal.
Recycle more
Unit 1: Dynamic Planet

Use cars less and public transport more.
1997 Kyoto Protocol
= international agreement to cut CO2 emissions.
Some countries e.g. UK have cut emissions, others e.g. China haven’t. We need ALL
countries to sign up.
NAMED EXAMPLE: Egypt – the
possible impacts of Global
Warming
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A developing country
Low greenhouse gas emissions – 2.6 tonnes per person per year (world average =
6.8)
Produce less than 1% all green house gases.
99% of Egypt’s people live in 5% land area as so much is desert.
Average rainfall = less than 10mm/yr
The River Nile is an important water supply.
With Global Warming…
 If sea levels rise 50cm, 1/3 of the city of Alexandria would be under water.
 10% Nile Delta would flood  7 million people would have to leave their homes.
 farming would be hit.  there would be less food famine.
 Less and more unreliable rainfall  water shortages.
 Desertification
 Heatwaves  illness and death.
 Malaria increase.
Water Wars??
86% of the Nile’s water starts it’s journey in Ethiopia.
Uganda, Sudan and Ethiopia are all building huge dams for Hydro Electric Power (HEP).
This could have a serious impact on the amount of water reaching Egypt.
This could lead to conflict and war.
Egypt has a debt of $30 billion. It may not be able to cope with the impacts of global
warming.
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Unit 1: Dynamic Planet
UNIT 3: BATTLE FOR THE BIOSPHERE
BIOME = WORLD SCALE ECOSYSTEM
The world has 9 major biomes – determined by climate:
 Temperature – length of the growing season
 Precipitation
 Sunshine hours – precipitation
 Humidity
Why does climate vary around the world?
LATITUDE:
At the equator the sun’s rays hit the earth at right angles, therefore
concentrating the insolation and making it very hot. At the poles the rays
hit at a greater angle, so the insolation is spread out over a greater area
and is much less concentrated.
At the equator the air is always rising = LOW pressure = clouds and rain =
rainforests.
At 30 degrees north and south of the equator the air is always sinking =
HIGH pressure = no clouds and no rain = deserts.
ALTITUDE: (height of the land) – as height increases so the climate gets increasingly
cold and wet. Temperature decreases 1 degree for every 100m of height.
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Unit 1: Dynamic Planet
THE SEA: keeps places near the coast cooler in summer and warmer in winter (as
water heats up and cools down more slowly than the land) this is called continentality.
PREVAILING WINDS: If the most common winds come from across the land, the
climate = dry. If across the sea, the climate – wet. From the poles = cold, from the
equator = warm.
A climate graph…
The RED line graph = average temperature for each month.
The BLUE bar graph = average rainfall for each month.
TEMPERAURE RANGE = difference between min and max
temperatures.
Goods and services
GOODS = things of value to us
SERVICES = things that satisfy our needs
BIOSPHERE GOODS
Fruit, nuts
Food crops
Meat, fish, wood
Biomass for energy
Drinking water, water for farming
Gene pool
BIOSPHERE SERVICES
Pollination for food webs
Climate regulation
Atmosphere gas balance (trees remove
co2 and give out oxygen)
Jobs
Recreation – tourism
Homes for humans and wildlife
Biodiversity
NAMED EXAMPLE: THE TROPICAL
RAINFORESTS
TRF indigenous people (lived their for many generations) - almost everything provided
by the rainforest:
 Wood for cooking and building
 herbs for medicine
 food – nuts, fruit, meat, fish
 grow crops – shifting cultivation (sustainable process)
BUT…
 TNC’s exploit the TRF
 logging for timber/paper
 farming – palm oil for example
 cattle ranches
 mining for oil
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 governments building dams for HEP
 roads
This means…
 The soil is eroded and washed away  floods.
 Wildlife loses habitats
 Rivers become dirty and polluted
PLAYERS… Different people and organisations who use the biosphere in different
ways.
NAMED EXAMPLE: The Guyana
Mountains Rainforest
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The Guyanan government is short of money and in debt.
They wanted to develop the rainforest for timber and mining.
Environmentalists and local people opposed this
How is the biosphere being degraded by human actions?
Every year the ‘red list’ of endangered animals is produced.
Increasingly, habitats are being damaged and destroyed  this leads to increased
threat of species survival.
Immediate causes = logging, overfishing, pollution
Root causes = increasing populations, economic development e.g. China, India  now =
more money and therefore consuming more food and fuel etc.
Certain species and places are particularly under threat.
There are 25 ‘hotspots’ where there is greatest concentration of biodiversity (number
of plants and animals).
OVERHARVESTING/OVERHUNT
ING/OVERFISHING
e.g. Krill
MINING
Oil e.g. Alaska
POLLUTION
air/water
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DEFORESTATION: Logging 
increased flooding and increased soil
erosion e.g. Amazon Rainforest.
Threats to the biosphere…
INTRODUCING ALIEN
SPECIES
CHANGING LANDUSE
to farmland/urban –
changes the ecosystem
TOURISM AND RECREATION
disturbs wildlife.
Unit 1: Dynamic Planet
How have ecosystems changed over time?
MASS EXTINCTION = extinction of a large number of species in a short time.
Are we heading towards another mass extinction? We are threatening the ability of
the biosphere to provide goods and services due to:
 Population growth
 Using more food, oil, water, minerals
 Human induced change (global warming)
Impacts of climate change on the biosphere:
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Habitats broken up
Habitats change due to increasing temperatures, changing rainfall, rising sea
levels
Extreme weather = more common
Oceans = more acidic as more freshwater is added. Kills coral reefs.
Increased pests and diseases.
Species face extinction
Krill numbers falling
Glaciers melting
Emperor penguins decreased 50%
How can we conserve the biosphere?
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Should we save the hotspots or a representation of all of the biomes?
Should we restore devastated areas?
Should we conserve high profile animals or keystone species (have a large effect
on other living things e.g. bees)
GLOBAL ACTIONS… (countries working together)
 RAMSAR  conserving wetlands
 CITES  stop ivory trade/crocodile skins
NATIONAL ACTIONS… (a particular country)
 National Parks England and Wales – protected areas e.g. The Peak District
 Community Forests – new areas of trees near cities
 Paying farmers to replace hedgerows
LOCAL ACTIONS… (local area)
 Biodversity action plans e.g Havering Wildlife Trust, Bedfords Park.
SUSTAINABLE MANAGEMENT – meeting the needs of the present without
compromising the needs of future generations.
Tropical Rainforests – make sure it isn’t used faster than it is renewed.
Ways to do this…
 Zoning
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Educating local people
Ecotourism
Protected areas
Only cut large trees
NAMED EXAMPLE: Klum,
Cameroon Republic:
Sustainable Forest Reserve
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an area of selective logging
tree nurseries to replace trees cut down (afforestation)
ecotourism
protected areas
crops grown beneath the trees instead of cutting them down.
UNIT 4: WATER WORLD
THE HYDROLOGICAL CYCLE
The hydrological cycle is a CLOSED SYSTEM – A finite amount of water going round
and round. None is added or lost.
STORES: rocks (can be stored for 100’s yrs), soil, lakes, oceans (97% water stored
BUT too salty to use) glaciers.
The soil, lakes and rocks hold relatively small amounts of fresh water – but are in high
demand as sources of water..
TRANSFERS/FLOWS: Surface runoff, throughflow, groundwater flow, infiltration,
precipitation.
Intercepts precipitation
22
½ is evapotranspiration without ever reaching the
ground = GREEN WATER
Unit 1: Dynamic Planet
Drips from leaves and infiltrates the soil
Water Crisis






Demand increases as population increases.
Increased demand from agriculture – irrigating their crops uses huge amounts
of water.
Supplies are increasingly unpredictable
Possibility of water wars – Middle East – fighting over water.
Economic development – China, India – increased demand for water
Rising living standards = use more water e.g. showers, washing machines etc.
Population growth
Tourism – hotels, golf
courses = huge amounts
of water
Agricultural demand
urbanisation
Decline in water availability and quality
Energy – reservoir
storage for HEP =
through evaporatio
Industrial developmen
Climate change = rain less reliable in some places
Only ½ freshwater runoff (BLUE WATER) is used.
Most is inaccessible.
WATER STRESS = when demand is greater than supply or when it is not of good
enough quality to use.
Turkmenistan and Uzbekistan are the most water stressed countries in the world 
they use huge quantities for irrigating cotton crops.
SW USA, Central Asia = PHYSICAL WATER SCARCITY – Demand > availability
Sub Saharan Africa = ECONOMIC WATER SCARCITY – supply available but people
can’t afford to exploit them. Lack of money to build storage facilities or distribute
water.
NAMED EXAMPLE: SAHEL

23
Belt of semi-arid land south of the Sahara, Africa.
Unit 1: Dynamic Planet




Rains usually 1 or 2 months a year. Total 250-450mm/yr.
Since 1970 rainfall has been below average. Some years 25% less than average.
Sometimes rainfall is so heavy when it does fall that most is lost as surface
runoff leading to flooding.
Other years there is no rain at all  rivers dry up  water table falls 
farmers crops fail  animals die  desertification  decreased food supplies
 famine.
Global warming means…



Less rain for some areas
Increased rate of glacier melt
More extreme weather events  floods and storms and droughts.
Richer countries e.g. Kuwait, Saudi Arabia (profit from oil) can buy their way out of
trouble e.g. desalination  turning sea water into fresh water (very expensive).
Developing countries rely on rainfall for their crops  + unstable  food insecurity and
famine.
Water quality…
People can suffer economic water stress if water isn’t safe. Pollution can be: domestic,
industrial, agricultural, transport related.
Salt runoff from roads
sewage
Disposal of hazardous waste
Cattle waste (slurry)
Fertilisers washed in
Sources of water pollution
Crop spraying
Runoff from building sites
Industrial discharge
Chemicals applied to golf courses
Developing countries…
 The highest levels of pollution are found in rapidly developing countries like
India and China – they put economic growth before environmental protection.
 Rapidly growing cities means slums  streams = badly polluted as no sewage
systems in place.
 Chemicals added to crops = runoff….
Developed countries…
 E.g. UK, Japan – have taken big steps to control pollution.
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Unit 1: Dynamic Planet

Tertiary and quaternary industries cause less pollution than primary and
secondary.
NAMED EXAMPLE:
– Japan – ‘60’s = heavily polluted rivers
and lakes. 70’s government introduced standards to improve water quality. Now much
better.
Impacts of pollution…



Diseases e.g. cholera
Eutrophication – fertilisers make algae grow really fast – takes all O2 out of
water – all living things in river/lake die.
Cancer (Erin Brokovitch)
Interfering in the hydrological cycle…
We use water for: farming, drinking, washing, industry, habitats for plants and animals,
power generation (HEP), waste disposal.
How people intervene in the water cycle:
1. CLOUD SEEDING: making it rain
2. DEFORESTATION: Decreased interception  increased flooding
3. URBANISATION: Increased impermeable surfaces
4. OVERABSTRACTION: taking too much water from rivers and lakes
5. BUILDING DAMS AND RESERVOIRS
6. GLOBAL WARMING: melting glaciers
OVERABSTRACTION: Too much water is being taken from the
river/lake/water source.
NAMED EXAMPLE:
Thames Valley, S. Eng.
 Dramatic decrease in river flow
 Tributaries dried up
 Ecosystem damaged
Droughts and increased demand from more homes  increased use of groundwater
supplies  falling water table so the store of water is not used sustainably.
 most water companies now have strict policies CAMS for managing water levels.
RESERVOIR BUILDING: Adds a new store to the hydrological cycle.
But….brings PROBLEMS:
 loss of land – drowns villages, farmland
 disease – stagnant water  mosquitoes
 vegetation drowned releases methane = greenhouse gas
BENEFITS:
 Water supply
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Unit 1: Dynamic Planet
 Recreation – fishing, sailing, walking, wildlife
DEFORESTATION





Fewer trees = less evapotranspiration. Less green water recycled = less rain.
Soil left exposed to the sun and rain
Less nutrients in the soil
Raindrops wash out the finer soil, leaving coarse, heavy surface.
Less interception  greater flood risk
Solutions to the water crisis…
If we use water faster than it can be replenished this is not sustainable
Large scale water management projects: Big dams
BENEFITS
 Increased water supply
 Recreational use
 HEP – Industry
 Habitat for water birds
 Fishing
DISADVANTAGES
 loss of farmland/villages
 less navigation
 people have to be relocated
 disease – stagnant water
 loss of cultural sites
 interferes with fish migration
NAMED EXAMPLE: china: south
to north water diversion
project



To transfer water from the south to the dry north.
Complete 2050
Loss of ancient sites, displaced people
NAMED EXAMPLE: three gorges
dam



To provide HEP and prevent flooding
Impacted biodiversity
1.4 million people had to be relocated
Small scale solutions…
NGO’s (Non Governmental Organisations) e.g. WaterAid develop small scale solutions.
APPROPRIATE/INTERMEDIATE SOLUTIONS: Schemes that meet the needs of local
people and the environment in which they live. Within their technical ability – they can
operate and maintain the scheme themselves. They can continue to run it when the
NGO has left e.g RAINWATER HARVESTING – using guttering to collect rainwater
and divert it into a tank. TUBE WELLS – to pump up water. LOW COST
PIT/COMPOSTING TOILETS.
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Unit 1: Dynamic Planet
NAMED EXAMPLE: DHAKA,
BANGLADESH
 Old Zhimkhana – slum on disused railway station. No safe water or toilets.
 WaterAid constructed 6 tube wells and 2 new sanitation blocks
 people are no longer continually ill
they can run facilities themselves
 moving out of poverty
In the past women had to walk long distances to get water. Now they have safe water
for drinking, cooking, washing and personal hygiene.
Problems of small scale schemes…

A huge number of people suffer from HIV/AIDS  too ill to operate.
In general, Intermediate technology is more sustainable than large scale schemes.
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Unit 1: Dynamic Planet
Topic 6 River Processes and Pressures
Don’t forget the role of rivers in the hydrological cycle; Hydrology is the study of water. The
hydrological cycle is the movement of water between the atmosphere, land and oceans.
 Precipitation - all forms of rainfall, snow, frost, hail and dew.
 Interception - precipitation that is collected and stored by
vegetation.
 Infiltration - water that seeps into the ground.
 Transpiration - water loss from vegetation to the atmosphere.
 Evapotranspiration - the combined losses of transpiration and evaporation.
 Water storage - the temporary storage of water in lakes, dams, reservoirs and rivers.
The main processes of a river at work
Erosion is the wearing away of land, there are 4 main types of erosion:
Diagram
Abrasion
(or corasion)
Bed
Attrition
Corrosion
(or solution)
Hydraulic
Pressure (or
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Channel
Type of Erosion
Explanation
This is when the river throws
material against the channel
This is caused when rocks and pebbles
bump into each other and break into
smaller pieces
This is where salts and other acids in
the salt water slowly dissolve away the
coast
This is when air gets trapped in a crack
in the river bank. The air gets
Unit 1: Dynamic Planet
hydraulic action)
compressed and expands, opening the
crack
Rivers can erode:
 Vertically – erodes material from the river bed
 Laterally – erodes material from the river banks
More acidic water
increases rates of
solution
Ph
Soft rocks erode faster
than harder rock
Human
Activity
Geology
Deforestation, dams
and bridges interfere
with the natural flow
Factors
Affecting
Erosion
The steeper the
gradient the greater
the erosion potential
Gradient
Load
The heavier and sharper
the load the greater the
erosion potential
Velocity
The faster the river
flow, the greater the
erosion potential
The material that the river carries is called its load. The load can be large boulders, rock, pebbles or
tiny grains of silt. How much load a river can carry depends on the energy or power the river has.
Transportation is how the load is carried within the river
 Traction – where large rocks and boulders are rolled
along the river bed.
 Saltation – where smaller stones are bounced along the
river bed in a leap frogging motion
 Suspension – where very small grains of sand or silt
are carried along with the water
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Unit 1: Dynamic Planet
 Solution – where some material is dissolved
(like sugar in a cup of tea) and is carried
downstream.
Deposition occurs when the river’s load is too big to carry and it can create some interesting and
unique features.
The most significant process within a river valley or drainage basin is erosion by the river itself.
Although the sub-aerial process of weathering which operates on the valley sides is important too!
Weathering is the breakdown of rocks in situ. This means it happens where the rock is. Rocks are
weakened by being chemically attacked and mechanically broken down. The main ways that rock is
weathered are:
Freeze-Thaw Weathering
Chemical Weathering
Most rain contains a small amount of acid. When it falls on rock it slowly eats into it. It makes
the rock rot and crumble away
Onion-Skin Weathering
The sun heats the rock and its outer layer expands. When it cools down at night it shrinks again.
After this happens many times, the outside of the rock peels off like an onion.
Biological Weathering
A seed falls into a crack in a rock and it may start to grow. As the roots grow they force the crack to
get wider. The rock breaks into pieces.
Mass movements can occur once the rock on the valley sides is broken up. The fragments of rock
can move fairly rapidly in the form of a landslide, or slowly, most common is soil creep.
 Landslides (and mudflows) are relatively rapid
movement of material. They are less common in the
UK, but can occur along the coast and railway
cuttings
 Soil creep is a slow process where slope
material moves at about 2cm per year. Over
decades it can have many effects such as, bent
trees, leaning telegraph poles and/or walls.
The shape of a river valley is affected by 3 things:
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Unit 1: Dynamic Planet
 The speed of weathering
 The speed of mass movements
 How quickly the river can move material brought by mass movements
The Long Profile of a River
A river has a very
distinct profile that
changes from
source to mouth.
There are distinct
sections of a rivers’
profile and each
section has features
and processes
associated with it.
The long profile is a
section along a river
from its source to
its mouth. The
upper section is
normally steep,
whereas the lower
section is usually flatter. The river is able to erode through its flood plain down to the new lower sea
level.
The UPPER course of a river is V-shaped. It has a steep gradient and
the valley is relatively narrow. The river is often quite shallow and
relatively fast flowing. There is lots of friction with the large boulders
found on its bed and the river uses most of its energy to overcome
friction. One of the most impressive features in this section is a
waterfall.
Waterfall Formation
Waterfalls frequently occur on horizontally
bedded rocks. The soft rock is undercut by
hydraulic action and abrasion. The weight of the
water and the lack of support cause the waterfall
to collapse and retreat. Over thousands of years
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Unit 1: Dynamic Planet
the waterfall may retreat enough to form a gorge of recession. Gorges form through the retreat of
waterfalls over thousands of years.
In the MIDDLE Course the slopes are gentle. Lateral (sideways)
erosion is beginning to form a flood plain. There is also a larger
volume of water in the river due to tributaries. One of the most
impressive features in this section of the river is a meander.
Meanders are caused by helical flow; this means water on the
outside of the bend moves faster and therefore erodes, while
the slower moving water is on the inside of the bend. This means
material is deposited to form a point bar (a little beach in the
inside bend).
Meander Formation
Continued erosion at the neck
of the meander can create an
Ox-bow Lake.
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Unit 1: Dynamic Planet
In the LOWER Course, the Valley sides are very gentle, almost flat. Typical processes include erosion
(on the outer banks, especially during times of flood), transport, and deposition (especially on the
inner bends and on the floodplain). Typical features include levees, ox-bow lakes, floodplains and
terraces. Intense use is made of lower courses of rivers on account of their gentle gradient, large
supply of water, fertile valleys, and terraces which are free from flooding.
A floodplain is an area of land at the side of a river that fills up when the river floods. Floodplains are
often flat and fertile and may be used for farming. However, floodplains normally flood each year, so
they may be used for animals rather than crops. Floodplains often contain levees and sometimes
they have ox-bow lakes.
A levee is a raised bank on the edge of a river, formed by deposition of
material each year when the river floods. When the river floods its
speed is reduced. As its speed is reduced it has to deposit some of its
load. It drops the coarser, heavier material first and the finer, lighter
material last. Levees are built up of coarse material, while the flood
plain consists of fine silt and clay.
Delta
For deltas to be formed a river needs to:
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Unit 1: Dynamic Planet
 Carry a large volume of sediment
 Enter a still body of water
The coarser material is deposited first, and the finest material last, and furthest away.
A river regime is the annual variation in the flow of a river. In Britain, river flows are higher in winter
because:
 higher rainfall
 lower temperatures and hence lower evapotranspiration
 less interception by deciduous vegetation
A storm hydrograph (or flood hydrograph) shows how
a river changes in response to a storm or period of
heavy rainfall. The rising limb shows how quickly the
flood waters begin to rise. The peak flow is the
maximum discharge of the river. The time lag is the
time between the height of the storm and the
maximum flow in the river. The recessional limb is the
speed with which the water level in the river declines
after the peak. Baseflow is the normal level of the
river, which is fed by groundwater.
Climate
Human
Activity
Soils
Factors
Affecting
Hydrographs
Drainage
Density
Slope
Angle
Vegetation
Infiltration
Capacity
Link
your
knowledge of
the hydrological cycle to
storm/flood hydrographs.
Rock Type
Urban hydrographs are different to rural ones.
Use the language of the hydrological cycle.
They have:
 A shorter time lag
 A steeper rising limb
 A higher peak flow
 A steeper recessional limb
34
This is because there are more impermeable surfaces in urban areas as well as more drainage
channels
Named Example: MEDC FLOOD: MORPETH, NORTHUMBERLAND
Where (location): Morpeth, market town in Northumberland, UK. On the banks of the River Wansbeck.
When: 6th September 2008, the River Wansbeck breached its banks. The narrow steep topography of the
Wansbeck Valley and increased urbanization caused exaggerated surface run-off and a lag time of only 8
hours.
Causes:
~ River Wansbeck has tributaries in the uplands of rural Northumberland and flows through many small
villages and towns along its course.
~ Environment Agency monitor river levels every 15 minutes
~ 150mm (6in) fell between Friday 5th and Saturday 6th October 2008
~ 24 hours of prolonged heavy rainfall filled river channels and saturated the catchment area
~ Highest ever peak discharge recorded by the EA
~ Narrow steep drainage basin which encourages overland flow
~ 8 hour lag time
~ Confluence just north of Morpeth
Effects:
~ 2000 homes flooded
~ People were being cared for at the Town Hall and local school. Many of them, especially the elderly, were
distressed at having to leave their homes
~ 1000 people evacuated
~ RAF helicopter from nearby Boulmer airlifted the most vulnerable
~ “Staff from Castle Morpeth are handing out sandbags on a priority basis.” As the Environment Agency issued
a flood alert for the whole of Morpeth
~ Major roadways in Durham and Northumberland were closed; with rural villages such as Powburn and
Rothbury completely cut off and isolated.
~ The wet weather in the area at this time also affected Newcastle City Centre and sporting events such as the
cricket at Durham.
~ Damage estimated to cost £10 million
~ Many homes and business are still unoccupied today
Response:
~ Fire crews using inflatable dingies ferried families to safety
~ Morpeth Lions coordinate a Flood Victims Appeal and collect donations from Newcastle to Alnwick.
~ Morpeth Rotary Club shop has received over 300 donations of pieces of furniture.
~ Immediate needs were addressed by the Red Cross
~ Red Cross volunteers are systematically calling at houses, street by street. In this way, they can quickly
identify those who have been adversely affected by the recent weather and ascertain what help they might
need.
~ Red Cross fire and emergency support vehicles are stations in streets as a focal point for information.
~ Local Authorities help with the clean up and re-house residents in social housing
~ RNLI lifeboat crews from Newbiggin-by-the-sea, Amble and Blyth also assisted with evacuations
Flood Management Methods
Type of flood management
Benefits of flood management
Costs of flood management
Cheap; easy to distribute
Not very effective in large floods; not easy for elderly
or people with disabilities to put in place
Store very large volumes of water; can be used for
multi-purpose schemes
Very expensive; can lead to unwanted impacts such
as increased tectonic activity, displacement of
people, silting of dam
Useful and flexible way of diverting flood waters away
from centres of population
Transfer the flood elsewhere; densely populated
areas may not have total flexibility in location of relief
channels
Relatively cheap and easy way of protecting one or
both sides of a river
Do not protect against very large floods
Sandbags
Dams
Relief channels
Raised banks (levees)
Unit 1: Dynamic Planet
Specification Check List
Unit 1 Topic 6: River
Processes and Pressures
SPECIFICATION CONTENT
I know what erosion is
I can describe how a rivers shapes its channel using 4
types of erosion
I know what transportation is
I can describe how a river transports its load (4 types)
I can explain the formation of a waterfall
I know what weathering is and can describe biological,
physical and chemical weathering
I know what mass movement is
I know what a meander is and how it is formed
I know what a flood plain is, where it is located and
some pressures placed on the flood plain
I can describe and explain the processes and features in
the upper, middle and lower course of a river
I can describe and explain a rivers long profile and cross
section
I can interpret storm hydrographs
I can explain, using the hydrological cycle, factors that
might cause flooding
I know the causes and effects of one named flood event
I can evaluate hard engineering strategies to prevent
flooding and give examples
I can evaluate soft engineering strategies to prevent
flooding and give examples
I can describe sustainable river management
37



ACTION
Unit 1: Dynamic Planet
Section C: Large-Scale Dynamic Planet
Oceans on the Edge
What you need to know:
1. Threats to the ocean
2. Ecosystem change
3. Increasing
exploitation
4. Sustainable
management
. How and why are some ecosystems threatened with destruction?
The term ecosystem describes a grouping of plants and animals that is linked with its local
physical environment. The oceans, covering two-thirds of our planet, are home to marine
ecosystem communities composed of fish, aquatic plants and sea birds- as well as tiny but very
important organisms such as krill and plankton.
HINT: make sure you are able to name some values of the Oceans e.g. its uses and value to
human and animal life.
TASK: make notes and research further the importance and value of CORAL REEFS AND
MANGROVE SWAMPS. Pg 102-103.
The way we use Oceans is becoming UNSUSTAINABLE this means we aren't treating/using it in
a way that will preserve it for future generations. Within the oceans here is a natural balance
between all life- these relationships form the FOOD WEB. Use page 104 to make a copy of the
Oceanic food web. It is also important to consider the NUTRIENT CYCLE which is the
movement and re-use of important substances e.g., nitrogen.
DISRUPTION’S TO FOOD WEBS the main three disruptions you need to understand are:
1. Over fishing
2. Eutrophication
3. Siltation
4. Tourism
5. Pollution
6. Habitat destruction
7. Food web destruction
Example: Overfishing of Krill – keystone species
 Eaten by:
 whales, penguins and fish.
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Unit 1: Dynamic Planet




Used for:
Omega 3 supplements
Fish farm food
Southern Ocean food web is below – shows why is Krill so important?

Climate change also disrupts the oceans.
1. Warmer water
2. More acidic water and bleaching
3. Higher sea levels
Nutrient overloading
The balance of nitrates,
phosphates ammonia and
chlorine is tipped and causes
a loss of oxygen due to algal
blooms.
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Unit 1: Dynamic Planet
2. How should ecosystems be managed sustainably?
There are two ways that marine ecosystems can be managed and that is again, as with the
other units, at a LOCAL and GLOBAL SCALE.
Case study on Firth of Clyde, Scotland (see next page to complete this activity). This is an
example of where humans are putting pressure on the marine wildlife and there are plans
to make the area more sustainable.
SUSTAINABLE MANAGEMENT AT A LOCAL SCALE
Managing coral reefs reefs are made of living animals, each piece contains polyp. They are
part of a large colony of marine life. The polyp are skeletal creatures that form coral in
clear, warm and sunlight seas.
Coral reefs are home to ¼ of the world’s fish species. It also acts as natural barriers that
protect the coastline from erosion. They are also great for tourism. However there are
sustainability issues that come with this. Complete the case study6 on Coral Triangle on
the case study section.
SUSTAINABLE MANAGEMENT AT A GLOBAL SCALE
Global actions are needed to tackle pollution and to save threatened species from overfishing
and extinction. International Organisations play a large role in ensuring that the oceans are
protected.
The United Nations Food and Agriculture Organisations regulates the management of deep sea
fisheries.
Individuals around the world can also ‘do their bit’ by changing their shopping habits to ensure
that we only buy sustainably sources fish and buy ‘dolphin friendly’ tuna.
Pressures in the Firth of Clyde,
Scotland page 109-111
The Firth of Clyde is a 60km
stretch of water along
Scotland’s West coast. It is
home to 40,000 animal and
microbe species. You can often
see seals, harbour porpoises
and basking sharks in this area.
Leather back Turtles and Killer Whales are sometimes seen as well. So it is
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Unit 1: Dynamic Planet
obviously an extremely important ecosystem. Make notes on the 4 main pressures
that humans put on this area. Which is the most severe and why?
1. Fishing
2. Tourism and leisure
3. Sewerage disposal
4. Military testing
What is the impact of scallop fishing in Lamlash Bay?
Locals views- what do the people think?
Future Plans?
Oceans on the edge
1. Using examples, describe the threats facing marine ecosystems (6)
Foundation
2. Using named examples, explain the short and long-term threats
facing marine ecosystems (6) Higher
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Unit 1: Dynamic Planet
3. Describe the type of area a mangrove swamp might be found (2)
4. How can an undisturbed mangrove swamp support human activities?
(2)
5. How could an increase in demand for one type of fish impact on the
food chain? (6)
6. Explain how the change in ocean s=currents could impact marine
ecosystems? (6)
7. Explain why the worlds oceans are under threat (4)
8. With reference to an example, explain the problems and successes
of sustainable fishing (4)
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Unit 1: Dynamic Planet
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Unit 1: Dynamic Planet
Battle for the Biosphere Glossary
Biodiversity – is the range of animal and plant life found in an area.
Biome – a world scale ecosystem.
Biosphere – the zone where life is found. It extends 3m below ground to about 30m above
ground and up to 200m deep in the oceans.
Continentality – the effect of distance from the sea.
Evapotranspiration – when water evaporates from the pores of leaves into the atmosphere. This
results in water being drawn up plant stems.
Indigenous Peoples – are people who have originated in and lived in a country for many
generations.
Keystone Species – a species that has a particularly large effect on other living organisms.
Mass Extinction – the extinction of a large number of species within a short period of
geological time.
Pressure Belts – regions of the atmosphere that run around the earth. They are parallel to the
equator. Some are high pressure areas, others are low pressure areas.
Sustainable – means a process that does no lasting harm to people or the environment.
Transnational Companies – are giant companies operating in many countries.
Climate and Change Glossary
Atmosphere – the layer of gases above the earth’s surface.
Climate – the average of weather conditions measured over a period of 30 years.
Climatologist – a scientist who is an expert in climate and climate change.
Weather – the short-term day to day changes in things like temperature, wind, cloud cover and
rainfall.
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Unit 1: Dynamic Planet
Desertification – the gradual change of land into desert.
Extinction – a species of plant or animal dies out completely so none survive.
Food Chain – plants provide food for plant eating animals (herbivores). Herbivores provide food
for meat-eating animals (carnivores). Plants and animals and linked together and depend
on each other.
Glacial – a long period of time during which the earth’s glaciers expanded wildly.
Interglacials – a long period of warmer conditions between glacials.
Megafauna – means ‘big animals’. Most weighed over 40kg and included the woolly mammoth,
giant elk, ground sloth, sabre-tooth cat, giant beaver and glyptodon.
Milankovitch Cycles – the three long term cycles in the earth’s orbit around the sun.
Milankovitch’s theory is that glacials happen when the three cycles match up I a certain
way.
Quaternary – the last 2.6 million years, during which there have been many glacials.
Stratosphere – the layer of air 10 – 50km above the earth’s surface. It is above the cloudy
layer we live in, called the troposphere.
The Greenhouse effect – the way that gases in the atmosphere trap heat from the sun. The
gases act like the glass in a greenhouse. They let heat in but prevent most of it from
getting out.
Restless Earth
Convection Current - When heat rises from the core it creates convection currents. These
currents are strong enough to move tectonic plates on the Earth’s surface.
Tectonic plate - The Earth’s surface is broken into many large pieces, like a cracked eggshell.
These different pieces are called tectonic plates.
Plate Boundary - The point at which two tectonic plates meet
Conservative boundary - When two plate boundaries are sliding alongside each other (causing
earthquakes).
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Unit 1: Dynamic Planet
Conservative boundary - When two plates are moving apart from each other and new crust is
created.
Destructive boundary - When two plates are moving towards each other and crust is destroyed.
Oceanic crust - The part of the Earth’s crust which is under the oceans.
Continental crust - The part of the Earth’s crust that makes the continents.
Pangaea - A supercontinent consisting of the whole land area of the globe before it was split up
by continental drift.
Volcano - A landform built up from lava and ash. Volcanoes come in many different forms.
Lava - melted rock that erupts from a volcano.
Magma - Melted rock below the Earth’s surface.
Stratovolcano - A cone shaped volcano formed when layers of ash and lava build up.
Earthquake - A sudden release of energy between two plates.
Focus - The point at which an earthquake occurs in the ground.
Epicentre - The point directly above the focus on the Earth’s surface.
Magnitude - The strength of an earthquake.
Richter scale - The scale on which we measure the magnitude of an Earthquake.
Evacuate - When people move from a place of danger to a safer place.
Water world
Hydrosphere - All of the water close to, or on, the surface of the Earth.
Closed system - A system which repeats continuously with no inputs or outputs
e.g. the hydrological cycle.
Open system - A system which involves inputs and outputs.
Hydrological Cycle - The movement of water between its different forms e.g. gas, (water
vapour) liquid and solid (ice) forms.
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Unit 1: Dynamic Planet
Biosphere - The zone in which life is found.
Lithosphere - The outer layers of the Earth’s surface (the crust and the upper mantle).
Precipitation - Moisture which falls from the sky including rain, snow, sleet, fog, mist and hail.
Evaporation - The changing of a liquid into a vapour or gas.
Interception - The capture of rainfall by leaves.
Infiltration - Movement of water into the soil from the surface
Percolation - Water flows vertically through soil and rocks
Groundwater storage - Water stored in rocks following percolation
Transpiration - Water vapour is released through the stomata in leaves
Throughflow - Water flows horizontally through the soil into the river
Surface runoff - Water flows horizontally over the land into the river
Saturation - When soil is full of moisture
Water Table - The level at which saturation occurs in the ground or soil.
Input - Things which enter a system
Output - Things which leave a system
Stores - when something is held within a system
Transfers or flows - movements within the system
Water Stress - Occurs when the demand for water exceeds the amount that is available during
a certain period.
Scarcity -Shortage of water due to either physical or economic constraints.
Eutrophication - The process by which ecosystems, usually lakes, become more fertile as
fertilizers and sewage flow in. The resultant loss of oxygen in water kills off all species that
need oxygen to survive e.g. fish.
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Unit 1: Dynamic Planet
Overabstraction - the name given when too much water is being taken from the river, lake or
another water source.
NGOs - Non-governmental Organisations e.g. WaterAid.
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