GCSE Geography Paper 1 (Physical)

tornadoes

vertical funnels of rapidly spinning air containing clouds, strong wind, rain & sometimes hail

move at 15-30kmph and can have wind speeds of over 400kmph

flooding

a consequence of extreme weather (heavy rainfall in a short time) when water overflows its natural / artificial banks onto land that’s usually dry

thunderstorms

rain, clouds, lightning, thunder, wind

lightning

a type of extreme weather seen during thunderstorms. a bolt can contain 1bil volts of electricity

dust storms

a type of extreme weather, happens when very strong winds carry clouds of dust across an area

weather vs climate

WEATHER: the day to day changes in the atmosphere

CLIMATE: the average weather of an area based on data collected over 30 years

warm air

warm air rises - when air is heated it expands, becomes les dense and starts to rise, creating low pressure

as the air rises it starts to cool and any water vapour in the air condenses, causing clouds to form & possibly rainfall

low pressure because the air is exerting less pressure on the earth

clouds, rainfall, wind, hurricanes

cold air

cold air falls - becomes more dense & falls towards the ground, creaitng high pressure. it’s pushing down so pressure increases

no rising air = no clouds/rain, so calm, sunny, hot days in summer & clear, cold days in winter

the global circulation system

the equator receives the most heat from the sun & the north/south pole the least. this causes a surplus of heat at the equator. to provide polar areas with heat the earth operates the GCS

GCS: hadley cell

at the equator hot air rises creating a low pressure system & a band of high rainfall

at 30° cool air sinks creating high pressure so clear skies & desert climates

GCS: polar cell

cold air sinks and moves away from the poles

GCS: ferrel cell

at 60^o there’s a band of low pressure as warm air from the ferrel cell mixes with cold air from the polar cell, creating rain

extreme weather

unexpected / unusual / unpredictable / severe / unseasonable weather

can take place over 1 day or a period of time

causes of extreme weather - temperature

the GCS can cause temps to be v high in high pressure areas around 30^o. there are few clouds (sinking air) so there’s little to block the sun’s energy. temps in polar regions are very low

causes of extreme weather - the albedo effect

albedo - how much a surface reflects / absorbs the sun’s rays

polar ice has high albedo so reflects more heat so the poles are colder

oceans & rainforests have low albedo so absorb more heat so they’re warmer

causes of extreme weather - clouds

clouds can both cool the plant (reflect sunlight) and warm it (trap infrared heat). low thick clouds reflect causing cooling, while high thin clouds trap causing warming

cooling - clouds act as a white shield, reflecting incoming sunlight back into space. this reduces the amount of energy reaching the surface, particularly with low altitude clouds

warming - clouds act as a blanket, trapping radiation emitted by the surface & reemitting it. this keeps the surface warmer

high clouds - thin & cold, let most sunlight through while trapping outgoing heat = net warming effect

low clouds - thick & warm, reflect substantial sunlight & emit heat similar to the surface = net cooling effect

causes of extreme weather - ocean currents

because water is fluid, ocean currents more heat easily

the UK is warmer than other countries at similar latitudes because it’s warmed by a warm ocean current from the caribbean

causes of extreme weather - altitude

higher up, pressure is lower so temps are cooler (~1^o per 100m altitude)

causes of extreme weather - precipitation

occurs when warm wet air rises & cools, causing water vapour to condense

air rises in low pressure belts so precipitation is frequent & intense in those areas. in high pressure belts air sinks & precipitation is v low

causes of extreme weather - wind

the movement of air from an area of high pressure to one of low pressure. greater pressure difference = stronger wind. (usually winds at ground level are slowed by friction)

trade winds blow from high pressure belts → low pressure belts

katabatic winds are caused by air flowing downhill

jet streams are high in the atmosphere and very strong as there’s little to slow them down

measuring wind

anemometers are used to measure wind speed by counting the number of times they rotate per minute

wind speed & direction can be shown using a rose chat

wind speed is measured using the Beaufort scale which ranges from 0 (calm) to 12 (hurricane)

australia vs uk - temperature

australia is warmer than the uk

in darwin (city in N australia) the average max summer temp is 33^oC. temps over 40^oC are considered extremely hot

in london the average max summer temp is 23^o. temps over 30^oC are considered extremely hot

australia vs uk - wind

australia has stronger extreme winds than the UK, partly because of tropical storms

strongest wind in australia is over 400km/h (recorded off the NW coast during a cyclone in 1996)

in the UK gales (winds 62kmph+) are rare. strongest every sea-level wind was over 220km/h (recorded in scotland in 1989)

australia vs uk - precipitation

australia has much lower precipitation than the UK

average annual rainfall in australia is 465mm. average annual rainfall in UK in over 1150mm

extremely wet years: 500mm+ in australia vs 1210mm+ in UK

extremely dry years: 360mm- in australia vs 950mm- in UK

tropical storms

powerful rotating storms, aka hurricanes, cyclones & typhoons depending on where they occur

form over tropical oceans & move east → west during summer & autumn, steered by trade winds

wind speeds over 120kmph, can be up to 650km wide & bring heavy rain (up to 250mm in 1 day)

a storm can last 6-14 days, bringing devastation to any land in its path

droughts

periods where there is much less precipitation over a specific time than is usual for the area, leading to water shortages. not no rainfall at all. an event of prolonged shortages in water supply, can be atmospheric (below average precipitation), surface water or ground water

can lead to food shortages, hunger & death

linked to long periods of high pressure - few clouds & so less precipitation. high temps also mean more water evaporates from plants, lakes & streams

can last for months / years / as little as 15 days

impact is worsened if people are using too much water or if water is being wasted

pacific normal conditions

winds blow east → west (south america → australia)

winds push warm water to the west making the sea levels in australia higher & warm. low pressure here due to warm water heating the air above it

peru = high pressure, v little rain

el nino

a weather event that takes place in the pacific ocean between australia & south america. happens every 5-7 years and involves a shift in the usual climate of the pacific ocean

el nino conditions in the pacific

usual winds reverse, blowing west→east

australia: cold ocean waters, falling air leading to high pressure, low rainfall, drought & wildfires

peru & south america: warm ocean waters, rising air leading to low pressure, high rainfall, storms & flooding

la nina conditions in the pacific

conditions are the same as a usual year but more extreme. could (but doesnt always) follow an el nino event

opposite impacts to el nino: australia = flooding, peru = droughts

tropical storm formation

occur in late summer & early autumn when oceans are warmest

form between 5^o & 15^o where trade winds meet. must be at least 5^o so the coriolis effect can start the storm spinning

ocean must be at least 26.5^oC and 60m deep. depend on a warm ocean for energy so it dies when reaching land. steered by light winds at sea

1. ocean water evaporates

2. air above the ocean warms up & rises

3. this creates low pressure which sucks in air from trade winds. winds spiral & absorb more moisture from the ocean

4. humid air forms storm clouds

5. cool air sinks, creating an area of calm, clear conditions (eye)

effects of tropical storms

strong winds can blow roofs of buildings, tear down trees & crops, damage communication & transport networks

heavy rain can cause short term flash flooding (especially in urban areas), mudslides & landslides, and flooding downstream

low air pressure raises the sea level (especially as the storm nears land) leading to coastal flooding

industries eg fishing, shipping, transport & tourism are vulnerable to tropical storms. millions of people living along coastlines are affected

typhoon hayan

hit the phillippines in november 2013. category 5 storm, winds over 315km/h

philippines stats

7th most populous nation in asia

population 98.4 people

LIDC, GDP per capita $2,765 (less money for preparation, defences, rebuilding)

typhoon haiyan impacts

worst impact = storm surge: 7.5m at the coast, 5m at Tacloban city where 5,800 people were killed.

90% of buildings in TC destroyed, electricity supplies cut, infrastructure & communications destroyed. 5 million people had their homes destroyed/become uninhabitable. airport unusable

estimated 6,340 fatalities, almost all in Tacloban city / the Visayas region

looting & assault during early days (only 100/1300 police officers reported for duty). relief trucks attacked & looted. martial law declared to maintain order

hospitals run low on supplies & shut (lack of staff, safety regulations)

agriculture, fishing, tourism & manufacturing industries damaged = large economic setbacks

storm surge

a sea level rise experienced in a tropical storm due to low pressure & strong winds

often causes coastal flooding & is the cause of most deaths in a tropical storm

typhoon haiyan responses

UN fundraising appeal raised $788 million. foreign nations donated total of $550 million. but total damage was over $8 billion and only 20% of those requiring aid had received it by mid november

attempts to move 1000s of people by military aircraft were slowed by miscommunication & panic

US sent marines & navy personnel, UK sent air force & navy

government grants for local fishing businesses to buy new boats. rice seed provided for farmers by oxfam. tent schools built by save the children

soft engineering schemes to reduce future storm impact: mangrove plantations & afforestation (create windbreaks & stabilise soil), Philippines Weather Service warnings via internet & social media

uk heatwave

2018 (joint hottest summer for UK). temps 35.3^oC

UK heatwave causes

jet stream was further north than usual meaning high pressure weather stayed over the UK for a long time & weren’t moved away

high pressure prevented formation of clouds/rain. higher jet stream prevented clouds & storms coming

jet stream

a high altitude band of wind that blows at high speeds east → west

UK heatwave impacts

4% revenue rise for businesses. ice cream sales rose by 24%, burgers by 14.4%, sausages by 5.1%

57% of population stayed in UK for summer = large tourism increase

UK economy gained total £31 billion (increased spending & staycations)

wildfires around manchester (winter hill & saddleworth moor). on SM 18km² burnt. fires spread quickly due to changing wind direction. only extinguished after 3 weeks. 150 people evacuated. ecological impacts estimated to last 15 years

that summer there were 663 more deaths than the average. the NHS & care homes struggled to cope

food & farming industry - yields decreased by 20% and food prices increased by 5%

underground reached temps over 40^o+, roads melted, rail tracks bent

driest summer in 57 years (only 15mm of rain in june) = low reservoir stocks & water shortages

UK heatwave responses

farmers were allowed to take more water from groundwater sources & river channel flow than usual for irrigation. however this raised criticism due to environmental impact

roads were shut down (melting tarmac), gritting trucks were put on standby, speed restrictions implemented for trains

hosepipe ban in august

structure of the earth

inner core: 1400km in diameter, solid & dense, made of iron & nickel, temps of 5500^oC

outer core: 2100km thick, semi-molten metal layer, temps of 5000-5500^oC

mantle: 2900km thick, semi-molten layer, less dense than outer core

crust: two types (continental / oceanic), thickness varies

earth’s crust & types

two types:

• oceanic: thinner (5-10km) but heavier & denser

• continental: thicker (25-90km) but older & lighter

oceanic crust is constantly being created & destroyed due to plate movement, because it’s denser so subducts under the continental crust. this means continental crust is much older than oceanic crust as it isn’t destroyed

tectonic plates + movement theories

the earth’s crust is broken into a number of tectonic plates which move on top of the semi-molten mantle below

tectonic theory once stated that their movement was due to convection currents in the mantle

current theory is ridge push & slab pull:

• ridge push: new crust forming at the constructive boundary which pushes the older crust away

• slab pull: the weight of the denser oceanic plates subducting and dragging the rest of the plate along

earthquake/plate boundary distribution

plate boundary/margin = where two plates meet

earthquakes occur at all types of plate boundaries. most (90%) occur along the pacific ‘ring of fire’

volcano distribution

most volcanoes occur at constructive & destructive plate boundaries. most (~75%) are located around the pacific ring of fire

hotspots occur away from plate boundaries

4 types of plate boundary

• constructive

• destructive

• conservative

• collision

constructive plate boundaries

plates are moving apart e.g. mid-atlantic ridge

both volcanoes & earthquakes occur

destructive plate boundary

plates are moving together. the denser heavier oceanic plate subducts under the lighter less dense continental plate

e.g. nazca plate & south american plate

both volcanoes & earthquakes occur

collision plate boundary

two continental plates are moving towards each other. they are less dense than the mantle below them so they don’t subduct & the crust is forced upwards forming fold mountains e.g. Himalayas

no volcanoes but earthquakes only

conservative plate boundary

plates move past each other in opposite directions/the same direction at different speeds. earthquakes only

causes of earthquakes at plate boundaries

earthquake = the sudden violent shaking of the ground. happen at all 4 plate boundaries

focus = the point at which the earthquake starts below the earth’s surface

epicentre = the point on the earth’s surface directly above the focus

measuring earthquakes

seismometers are used to record the size of the seismic waves

the magnitude (amount of energy released) is measured on the moment magnitude scale which replaced the richter scale.

the damage caused by earthquakes is measured on the mercalli scale, which goes from 1 (not felt) to 10 (extreme)

deep focus earthquakes

the depth of the focus can affect the impact of an earthquake

deep focus = depth > 70km

• often at destructive plate boundaries

• very powerful

• seismic waves move vertically so smaller area of effect

shallow focus earthquakes

the depth of the focus can affect the impact of an earthquake

shallow focus = depth < 70km

• all plate boundaries

• less powerful

• seismic waves move horizontally so larger area of affect

how earthquakes happen - sequence

the same regardless of the boundary:

1. as tectonic plates move they get stuck

2. pressure builds up as the plates continue to try move

3. eventually they jolt free & the pressure is released as energy

4. earthquake starts at the focus, epicentre is above that

5. energy passes through the earth’s crust as waves - the earthquake

earthquakes can happen due to human activity e.g. drilling into the crust / mining

measuring volcano magnitude

measured on the Volcanic Explosivity Index (VEI) - an open ended scale but the highest recorded in human history was an 8 (tambora 1815)

features of a volcano

volcanoes are formed when magma erupts onto the earth’s surface as lava through a vent in the earth’s crust

types of volcanoes

due to the type of lava erupted the formation of a volcano varies. there are 2 types, composite & shield

types of volcanoes: composite volcanoes

aka strato-volcanoes

• steep sided

• viscous (sticky) lava

• more explosive eruptions

• formed from alternating layers of ash & lava

• tend to be on destructive plate boundaries

types of volcanoes: shield volcanoes

• gently sloping sides

• runny/thin lava

• less explosive, gentle eruptions

• tend to form on constructive plate boundaries or hot spots

• frequent eruptions

hot spot volcanoes

at a hot spot the tectonic plate passes over a plume of magma & the magma rises to the surface through cracks in the crust. as the tectonic plate moves slowly over the magma plume a line of islands may form e.g. hawaii

nepal background info

one of the poorest countries in the world - GDP of under $1000

landlocked, between china & india

in 2015 80% of the population lived in rural, often remote communities

nepal earthquake background info

25 april 2015 at 11:26am nepal was struck by an earthquake with a magnitude of 7.8

the epicentre was 80km northwest of kathmandu (the capital) in the gorka district

it had a shallow focus - only 15km beneath the surface

over 300 aftershocks followed the main earthquake

cause of nepal earthquake

caused because nepal is located on a collision boundary between the indian & eurasian plates

nepal earthquake effects

• ~9000 deaths

• over 20,000 people injured

• 7,000 schools & 1,000 health facilities were damaged

• almost 3.5 million people were made homeless

• offices, shops & factories were destroyed so people couldn’t make a living

• UNESCO world heritage sites and many temples were destroyed

• loss of tourist income which nepal is reliant on

• avalances on mount everest & in the langtang valley

• landslides blocked roads & rivers

• damages estimated between $7-10 billion - ~35% of GDP

immediate responses to nepal earthquake

$3 billion donations of money & aid from around the world - $3.3 million from china & $51 million from UK

many countries sent aid in the form of temporary shelters, medicines, food, water, clothes, search & rescue teams, medical staff

90% of the nepalese army was mobilised

tent cities were set up in kathmanu for those made homeless

GIS crisis mapping tool was used to coordinate the response

$3 million grant was provided by the asian development bank for emergency relief

long term reponses to nepal earthquake

landslides were cleared & roads repaired to restore access to remote rural communities

schools were rebuilt

earthquake drills were introduced to give people education on what to do in an earthquake

stricter building codes with more enforcement were introduced

$200 million was provided by the asian development bank for rebuilding

a new government task force was set up to plan for future earthquake events

monitoring of earthquakes

accurate prediction of earthquakes isn’t currently possible but monitoring is. many different monitoring methods are being used to help research possible prediction methods e.g:

• tiltmeters - monitor ground changes

• clusters of small earthquakes

• changes in radon gas emissions

• changes in animal behaviour

• remote sensing of ground movement using satellites

preparation for earthquakes

countries can prepare for earthquakes in 4 main ways:

• building design + earthquake resistant structures

• land use planning

• earthquake drills

• emergency planning

earthquake preparation: building design

in developed countries building design & engineering is common to reduce the impact of earthquakes

building regulations & codes require new buildings to include earthquake resistant features e.g:

• shutters on windows to prevent falling glass

• cross bracing of steel frames

• foundations sunk deep into bedrock

• frames which sway with earthquake tremors

• rubber shock absorbers to reduce tremors moving through the building

earthquake preparation: land use planning

mapping areas most at risk from earthquakes

planning can ensure valuable services e.g. fire service & hospitals aren’t build in high risk areas

densely populated housing can be located away from high risk areas

earthquake preparation: drills & education

in many countries earthquake drills are regularly carried out. they help people prepare for what to do in an earthquake to protect themselves

education about how to prepare homes means people are less likely to be injured by falling objects & furniture

earthquake remote sensing & GIS

remote sensing of the earth’s surface by satellites like Sentinel 1 provides data about changes in ground movement

geographic information systems (GIS) provides layers of data e.g. vulnerable areas, land use & infrastructure like roads. this data is then used to assist with land use planning

earthquake management in nepal (developing country)

earthquake experts view kathmandu as one of the most dangerous places in the world for earthquake risk

in 1977 the government created the kathmanu valley earthquake risk management project (KVERMP) which included the school earthquake safety program (SESP) which provided funding to schools for earthquake drills, training to make buildings more resistant to earthquakes, and earthquake safety day. however this was mainly in urban areas so people in rural areas didn’t have drills or knowledge. the 121 recognised languages in nepal make communication of advice & education difficult

83 open spaces around kathmanu were allocated to be used as camps for displaced populations where they would be supplied with shelter, food & medical services. however there weren’t enough supplies to begin with

the improved 1994 national building code & training building inspectors. however the building code was often ignored so many buildings still weren’t earthquake resistant

government’s 2009 national strategy for disaster risk management & 2010 national emergency operations centre to coordinate the humanitarian response & restoration of infrastructure. however due to political instability they weren’t as effective

nepal red cross society maintained 12 warehouses with stocks of emergency supplies. but these weren’t enough for the scale of the disaster

earthquake management in japan (developed country)

japan is one of the wealthiest countries in the world - GDP per capita $48,000. also one of the most seismically active places with 20% earthquakes over magnitude 6 happening there

earthquake drills practised regularly so people know what to do during + after an earthquake. but people weren’t prepared for tsunami

people were encouraged to have an emergency survival bag always packed & ready. but many didn’t have it

buildings were designed to be earthquake resistant, building codes tightened after 1995 kope earthquake, over 80% of buildings in tokyo are earthquake resistant. but many buildings didn’t survive the tsunami

3-10m sea walls built in some coastal areas + breakwaters off the coast at kamashi & ofunato bay. but the tsunami overtopped the sea walls

trains automatically stop when an earthquake is detected to avoid derailments + nuclear power stations automatically shut down. but there was an issue restoring the cooling system at the fukushima nuclear power plant leading to radioactive contamination in the area

$20 million tsunami warning service with 180 seismic stations & 80 water based sensors. warnings issued via phone, tv, sirens & loudspeakers. but people ignored tsunami warning as they thought they’d be protected by sea walls

climate change definition

large scale, long term changes in average temperatures and weather patterns

past patterns of climate change

global climate conditions of earth change over time leading to colder & warmer periods

last 2.6 million years = quaternary period. in this there have been glacial (colder) periods and interglacial (warmer) periods

ice age = whenever the earth has permanent ice sheets. non ice ages are greenhouse periods

climate proxies: ice cores

cross sections of arctic/antarctic ice which trap ash, air bubbles & microbes. air bubbles contain CO₂ providing information about past temps

give info about the climate for the last 2.6 million years

climate proxies: global temperature data

records of temps across the world have been kept from around 1880. scientists can use records to study the earth’s temp & compare it to different time periods, work out global average temps & develop lists of hottest / coldest years

climate proxies: sea ice positions

sea ice forms when the ocean freezes

landfast ice = sea ice that’s attached to land

global warming means there’s less sea ice and ice breaks apart easily. arctic sea ice is at an all time low

comparing photos (e.g. from 1900s and recent satellite images) can sow how much ice levels have decreased

but they aren’t very reliable as they provide comparison not quantitative data and can be edited

climate proxies: tree rings

each ring of a tree shows 1 year’s growth. warmer period = trees grow more = larger rings. fossilised tree remains enable scientists to examine the climate over thousands of years

climate proxies: art & diaries

paintings & diaries provide evidence seen by people in the past e.g. paintings of the frost fairs on the river thames in london in the 1800s, diaries kept by people like a farmer from north-west england from 1815

the natural greenhouse effect

essential to the survival of earth

1. greenhouse gases in the atmosphere allow short-wave radiation from the sun through to the earth’s surface

2. the radiation reflects off the earth’s surface (becoming long-wave radiation aka heat) & greenhouse gases absorb some of it & stop it from radiating out into space

3. this heats the earth up & maintains its average temp

without the greenhouse effect the average temp would be -18^o

greenhouse gasses from natural sources

water vapour - evaporation from the oceans/seas & palnts

carbon dioxide - volcanic eruptions, wildfires, respiration

methane - oceans & soils from decomposition, termites

nitrous oxide - soils & oceans

causes of natural climate change: milankovitch cycles

long term changes to the earth’s orbit an position which change how much solar radiation the earth receives

• obliquity - how the earth tilts on its axis

  • varies every 40,000 years. greater tilt = more severe seasons

• precession - how the earth wobbles on its axis

  • every 24,000 years. can affect seasonal temps

• eccentricity - changes in the shape of the earth’s orbit

  • changes every 100,000 years. more circular = colder, more elliptical = warmer

causes of natural climate change: volcanic eruptions

large scale eruptions lead to vast quantities of ash being ejected into the atmosphere, which blocks solar radiation, leading to a decrease in temps

when mount Pinatubo in the Philippines erupted in 1991 it put 20 million tones of sulphur dioxide & ask 20 miles into the atmosphere, reducing global sunlight by 10% and cooling the planet by 1.3^o for 2 years

causes of natural climate change: sunspots

sunspots = dark spots on the sun’s surface

increased sunspot activity = higher average temps - sunspots show that the sun’s effectiveness at radiating heat is increased. however the IPCC states that the role of sunspots in climate change is minimal

natural vs enhanced greenhouse effect

human sources of greenhouse gases

carbon dioxide (CO₂): released from burning of fossil fuels in power stations & vehicles, burning of wood, deforestation (as less CO2 is removed from atmosphere)

methane (CH₄): released from decay of organic matter eg manure, landfill waste, crops, also released by cattle and during rice cultivation

nitrous oxide (N₂O): released from artificial fertilisers & burning fossil fuels

chlorofluorocarbons (CFCs): released from aerosols, refrigeration units & air conditioning

human causes of climate change

fossil fuels account for ~50% of global greenhouse emissions. used in transport, construction, heating, manufacturing & energy production

agriculture - deforestation to clear land for grazing/crops means less CO2 is absorbed in photosynthesis. production of fertilisers & pesticides uses fossil fuels. increased dairy & beef cattle + rice cultivation increases methane emissions. artificial fertilisers increase nitrogen oxide emissions

construction - cement manufacture releases CO2 (made from limestone which contains carbon)

transport - increasing global population = more cars/lorries/planes. more transport uses petrol/diesel which comes from oil which releases CO2

sea level rise as a result of climate change

sea level has risen 20-23cm since 1880. each year it rises another 3.2mm. it’s estimated that 410 million people will be at risk from sea level rise by 2100. there are 3 reasons for sea level rise:

• thermal expansion - water expands when warm so volume of water increases

• melting glaciers & ice sheets adds water to seas/oceans

impacts:

social - displacement of people from homes & communities, food & water supplies threatened from salt intrusion (salt in freshwater stores), food shortages lead to malnutrition & famine

environmental - destruction of ecosystems eg coral reefs & mangroves, ocean acidification, increased coastal erosion, changing patterns of animal migration & behaviour

economic - cost of flood defences increases, relocation of people & building new homes is expensive, loss of jobs, reduction in tourism due to impact on coastal resorts

in the Maldives over 80% of islands are >1m above sea level & it’s been forecast that if sea continues to rise islands will be uninhabitable by 2050. the government has constructed an artificial island (Hulhumalé) as well as flood walls & defences around islands

ocean acidification

decreasing pH levels due to increasing levels of carbon dioxide absorbed by ocean/sea water

extreme weather events as a result of climate change

warmer sea/ocean temps = more evaporation = more frequent & severe storms. droughts & heatwaves are more common due to increasing global temps

the intergovernmental panel on climate change predicts that a 1.5^o increase in average global temp will make 1 in 50 year heatwaves 8.5x more likely, 1 in 10 year droughts 2x more likely, and 1 in 10 year storms 1.5x more likely

extreme weather events like flooding & drought are forcing people to move - UN says an annual average of 21.5 million people were displaced by weather related events between 2008-2016. this could rise to a total of 1.2 billion people displaced by 2050. impacts include:

• social - people displaced, food & water supplies threatened by flooding & drought, reduction of crop yields (20% in sub-saharan africa), food shortages = malnutrition & famine, less rain = lack of freshwater, higher temps & flooding = spread of disease

• environmental - destruction of ecosystems eg coral reef bleaching & wildfires destroying forests, increased sea temps, changing animal behaviour / migration / hibernation, reduced biodiversity due to loss of species

• economic - relocation & building new homes is expensive, loss of jobs, repairs are expensive, loss of crops reduces income & exports, decline in tourism eg lack of snowfall in ski resorts, extreme temps deterring visitors

changing weather patterns in the UK as a result of climate change

all 10 warmest years on record were in the last 20 years and 6 of the 10 wettest years were in the last 25 years. it’s predicted that by 2050 the UK will have higher average temps, wetter winters and drier summers. impacts include:

• social - increased deaths in extreme heat especially people with respiratory & heart conditions, fewer deaths from cold, increase in hosepipe bans

• environmental - ecosystems affected by drought / flooding / wildfires, changes in species due to higher temps

• economic - increase in tourism due to warmer drier climate, longer growing systems increase income & exports, new warmer plants introduced, less water available for irrigation & power stations

landscape

the character of an area, resulting from the action and interaction of natural & human elements

a landscape’s character will depend on its initial geology, which gives the landscape its relief, which attracts human action/interaction. for example slate found in the mountains of north Wales attracted quarrying

very few landscapes are totally natural - people have had some sort of impact eg planting trees

the UK’s landscape is dynamic (constantly changing):

• glaciers once covered the majority of the country

• the sea surrounds the land making the UK an island with a changing coastline

• rivers flow across the land from their sources to the seas

elements of a landscape

natural/physical: physical features eg mountains & coastlines, water eg lakes, rivers, ponds

human: human aspect eg farmland & buildings, infrastructure eg pylons & fences, landscaped eg road verges & gardens

biological: the living element eg trees, grass, animals, habitats eg marshlands & hedges

variable: temporary - seasonal or weather dependent things eg frozen lakes or storms, weather & couds, smells & sounds

distribution of UK landscapes

uplands are found mostly in the north & west e.g. northern ireland, scotland, wales and north england (eg lake district, grampian mountains, snowdonia)

lowlands are found in the south & east - central & southern england (eg cotswolds, norfolk, south downs)

most cities are in lowland areas and often on main river courses e.g. liverpool on the mersey, bristol on the severn estuary & river avon

glaciation in the UK

europe’s last ice age peaked 20,000 years ago & ended 11,500 years ago. at that time 30% of the world’s land was covered in ice. temps remained below 0^o all year in northern regions like scotland, allowing a 1km thick ice sheet to cover most of the country

ireland, wales, northern england, scotland, and the midlands were covered in perpetual ice, and much of the country was uninhabitable for humans

during the ice age, areas covered in ice were weathered & eroded to create a dramatic mountain scenery. afterwards, those areas were exposed as deep valleys with sediment deposits

today much of upland britain is covered in u-shaped valleys and steep, eroded mountain peaks