Component 1 - Hazardous Earth Flashcards
What are the 3 cells?
1.Hadley
2.Ferrel
3.Polar
How does air move around the Earth due to cells?
1.The sun warms the Earth at the equator, which causes air to rise. This creates a low pressure belt. As the air rises, it cools and condenses and forms clouds and rain.
2.The cool, dry air moves out to 30° N and S of the equator
3.Here the cool air sinks, creating a high pressure belt, with cloudless skies and very low rainfall.
4.The cool air then moves as wind back to the equator, forming a Hadley cell, or towards the poles.
5.At 60° N and S of the equator, the warmer surface winds meet colder air from the poles. The warm air is less dense so is forced to rise, creating low pressure and frontal rain.
6.Some of the air moves back towards the equator, forming a Ferrel cell, some goes towards the poles.
7.At the poles, the cool air sinks creating high pressure. The high pressure air is drawn back to the equator as wind, forming a polar cell.
What is frontal rain?
rain that forms where the warm and cold air masses meet
What are trade winds?
surface winds which blow towards the equator
What are westerlies?
surface winds blowing towards the poles.
What is thermohaline circulation?
The cycle of cooling and sinking of water, which moves water around the earth in a big loop
How are surface currents made and what do they do?
- caused by winds
- They transfer heat away from the equator, eg the gulf stream
How do deep ocean currents work?
1.When water freezes at the poles, surrounding water gets saltier and denser
2.This makes it sinking, causing warmer water to flow in at the surface, creating a current
3.The warmer water cools, creating a cycle
How are arid climates made?
- Sinking air from the Hadley and Ferrel cells causes high pressure.
- This means rainfall is low, and termperatures are warm for most of the year.
How are polar climates made?
1.Sinking air from the polar cells creates an area of high pressure at the poles.
2.This means temperatures are low all year round and there’s very little rainfall.
How are tropical climates made?
1.Rising air from the 2 Hadley cells meeting causes low pressure.
2.This results in high rainfall and high temperatures all year round.
How has the Earth’s climate changed in the period before and during the Quarternary period?
- Before, it was warmer and quite stable.
- During, global temp has shifted between glacial periods, that last 100,000 yrs, and warmer interglacial periods, lasting 10,000 yrs
- The last glacial period ended 15,000 yrs ago, the Earth is currently warming
What are the 3 orbital changes which can change the climate?
1.Eccentricity - where the Earth’s orbit goes between circular and eliptical every 96k years
2.Tilt - where the Earth’s tilt changes angle over 41k yrs
3.Precession - where the axis of the Earth wobbles every 22k yrs
How do the 3 orbital changes affect the climate?
The cycles change the amount of solar radiation the Earth gets.
What are the 4 natural causes of climate change?
- Orbital changes
- Volcanic activity
- Solar output
- Asteroid collision
How does volcanic activity affect the Earth’s climate?
1.Major eruption eject large amounts of material like ash into the atmosphere
2.Some of these particles reflect the sun’s energy back into space, so the Earth cools
3.This causes a short term cooling in the climatge, eg - Mount Tambora in 1815, which led to the year without summer in 1816
How do asteroid collisions affect climate?
1.Asteroids hitting the Earth throw up huge amounts of dust into the atmosphere
2.These particles prevent the Sun’s energy from reaching the Earth, causing temperatures to fall for several years
How does solar output affect climate?
1.The sun’s output of energy changes in short cycles of 11yrs, and longer cycles of hundereds of years
2.Sunspot activity/solar flares result in more energy from the sun, raising temperatures/
What are 3 pieces of evidence for past climate change?
1.Tree rings
2.Ice cores
3.Historical records
How can we detect past climate change through tree rings?
1.The thickness of each ring depends on the climate that year
2.If it is warmer then the rings are thicker, else they’re thinner.
How can we detect past climate change through ice cores?
1.1 layer of ice is formed every yr in ice sheets
2.We drill in to the ice sheets to get long cores
3.By analysing the gases, eg CO2, trapped in the layers of ice, we can tell what the temperature was like that year.
How can historical records tell us about past climate change?
1.Since the 1850s global temp has been measured with thermometer
2.Historical diaries can show what the climate was like in the past, by giving the dates of harvests and days of rain/snow.
3.Paintings and news articles of fairs and markets on a frozen Thames show that winters in Europe were colder back then
What was the medieval warm period?
1.A period of relatively high temps between 900-1300AD
2.Harvest records show England was warm enough to grow large amounts of grapes
What was the Little Ice Age?
1.A period of cooling after the medieval warm period
2.Paintings from the 17th centure show the London Frost Fairs on the Thames.
3.Historical records show Arctic Ice reaching Scotland.
Radiation waves coming in are ____ and going out are _____
Radiation waves coming in are short and going out are long
What 4 ways are humans causing the enhanced greenhouse effect?
1.Farming
2.industry
3.Energy
4.Transport
What is the enhanced greenhouse effect?
Human activities causing global warming by making the greenhouse effect stronger
How does Farming cause the enhanced greenhouse effect?
1.Farming cows releases a lot of methane
2.Rice paddies emit methane from flooded fields
3.Trees absorb and store CO2. Deforesting for farming prevents this.
How does Industry cause the enhanced greenhouse effect?
1.Industry uses a lot of energy, to get this they burn fossil fuels, which releases greenhouse gases
2.some industrial processes, eg making cement from limestone, releases CO2
3.Industrial waste decays and releases methane
How does Energy production cause the enhanced greenhouse effect?
- CO2 is released into the atmosphere when burning fossil fuels
How does Transport cause the enhanced greenhouse effect?
- Most vehicles run on fossil fuels, which release greenhouse gases
- Car ownership has rapidly risen due to rapid development
- Increased congestion causes even more emissions
What 4 pieces of evidence is there to support the fact that humans are causing climate change?
1.declining arctic ice
2.global temp rise
3.sea level rise and warming oceans
4.extreme weather events
How does declining sea ice support human caused climate change?
- Sea ice forms in winter when ocean temps fall below 1.8°C.
- The extent of this ice has decreased 3% each decade over the past 35 yrs
How do global temp rises support human caused climate change?
1.Temps have increased by nearly 1°C since 1880, and ar expected to rise between 0.3-4.8°C between 2005-2100
2.The top ten warmest years have all been since 2000
How does sea level rise and warming oceans support human climate change?
1.Since 1901 sea levels have risen by 0.2m.
2.Glaciers melting and warmer water causes sea levels to rise
What is eustatic sea level rise?
- warmer temps cause glaciers to shrink and melt.
- The melting of ice on land then flows into the seas and causes it to rise
What is thermal expansion?
1.water in the oceans expands as it gets warmer, causing sea level rise
How do extreme weather events support human caused climate change?
- since 1905, there has been a higher freq. of heat waves in many areas, with less cold weather extremes
- In the UK, more rainfall records were broken between 2010-20 than in any other decade.
how does climate change impact people?
1.more deaths due to heat
2.more damage in coastal and low lying areas due to rising sea levels
3.many crop yields will fall, causing malnutrition
4.weather is getting more extreme, so more money must be spent to predict and protect
Why is there a lot of uncertainty around future climate change?
1.we don’t know how emissions will change as it’s hard to predict how population will grow and how governments will act and develop
2.we don’t know the exact climate changes each scenario will cause as we don’t fully understand the natural processes.
3.we don’t know what attmepts there will be to reduce human caused climate change
How do tropical cyclones develop?
1.they develop when the sea temp is 26.5° or higher and when the wind shear between higher and lower parts of the atmosphere are low
2.They form between 5-30° N and S of the equator, any further and the water is too cold.
3.Warm, moist air rises and condensation occurs, this releases huge amounts of energy making the storm powerful. The rising air creates and area of low pressure, causing high winds
4.The Earth’s rotation deflects the path of winds which causes the cyclone to spin ( coriolis effect)
5.The cyclone then travels towards the west because of the easterly winds near the equator
6.As it ventures away form the equator, they curve east because of westerlies
What causes cyclones to dissipate?
1.When they move over land or cooler water, their warm water energy supply is cut off so they weaken
2.Changes in windspeed from meeting other weather systems can also weaken cyclones
What is the structure of a cyclone?
1.The eye is up to 50km across and is caused by descending air. There’s very low pressure,light winds,no clouds, no rain and warm temps.
2.The eyewall is where there’s spiralling rising air, very strong winds, storm clouds and torrential rain and low temps
3.The edges of the cyclone is where the wind speed falls, clouds become smaller, rain becomes less intense and the temp increases.
What are the physical hazards of tropical cyclones?
1.High winds
2.intense rainfall
3.storm surges - a large rise in sea level caused by low pressure and high winds.
4.Coastal flooding
5.Landslides.
How can the physical hazards of cyclones impact people?
1.People may drown in the strong currents created by storm surges
2.Windspeeds can destroy buildings
3.high winds and floodwater can carry debris, killing people
4.Electricity supplies are cut
5.Flooding can cause sewage overflows
6.Crops are damaged
7.roads are damaged
What impacts do cyclones have on the environment?
1.Trees are uprooted by high winds
2.Storm surges can erode beaches and damage coastal habitats
3.Flooding can pollute freshwater environments with salt
4.Landslides can deposit sediment in rivers, killing wildlife
5.Flooding can damage industrial buildings on the coast, which can leak toxic stuff
How can we prepare and respond to cyclones?
1.Forecasting - allows for early preparing
2.Evacuation - Allows people to get to safer places, saving lives
3.Defences - reduce the damage done by the storms
What makes Mozambique a vulnerable to cyclones?
- 50% of population lives on low lying land.
- This is easily flooded which is bad for the 75% of people working in agriculture.
- Mozambique is in the tropics and has a long coastline
- There are 9 major rivers which can easily flood
- Sea level rise will make all this worse.
What were the social impacts of Cyclone Idai?
1.1300 people died
2.The winds were so strong, roofs were destroyed and people drowned
3.Cholera spread quickly in Mozambique
4.Safe zones got flooded
5.People in rural areas were unaware of the warnings
What were the economic impacts of Cyclone Idai?
1.$2Bn cost
2.90% of structures were damaged in Beira
3.Crops were wiped out by floods, and were unable to be replaced for 2 years.
4.Power and clean water were unavailable
5.This affected the poorest most as rural areas received little help.
What were the environmental impacts of Cyclone Idai?
1.Cyclone was slow moving so lots of water fell
2.Storm surges of 4m
3.Floods of 6m
4.Floods hit later as rivers burst their banks later
5.Many landslides killed 180 people.
What preparation was there in the lead up to Cyclone Idai?
1.Safe zones were designated - higher land areas basically
2.3 days of warning was given for evacuation, though this didn’t reach many rural areas.
Why did Cyclone Idai cause secondatry flash floods?
Mozambique uses a lot of dams, which took time to burst, then leading to more floods.
What are the secondary impacts of Idai?
1.Disease spread
2.Landslides
3.Secondary flash floods.
When was Cyclone Idai?
13-14 March 2019
How did Mozambique protect itself from future tropical cyclones?
Mangrove planting - the Mozambique gov plans to plant 5000 hectares of mangroves
What is mangrove management strategy?
1.An inexpensive form of defence against storm surges, as the mangroves absorb the energy.
2.They provide habitat for wildlife, and clean pollution
What are the criticisms of mangroves in Mozambique?
They need their coastline for trade, which is being covered by mangroves.
What were the responses to Cyclone Idai, to reduce the impact of future cyclones?
1.Mangrove barriers
2.better early warning systems
3.building better evacuation routes and shelters.
What catergory was Hurricane Sandy when over Cuba?
Cat 5
What was the path of Hurricane Sandy?
1.It began in the Carribean
2.Then headed North, picking up energy from the warm water
3.It went along the US east coast and combined with Nor’easter Athena to create a superstorm 100km wide.
4.It then cut in and hit NYC
What made Sandy unique?
1.Sandy was late in the hurricane season, and combined with Nor’easter Athena, which was early
2.No bermuda high to block hurricanes
3.The gulf stram was 3°warmer than usual
What were the economic impacts of Sandy?
1.Transport infrastructure was damaged, hurting trade and travel
2.$20Bn in economic losses
3.350k homes destroyed
4.8.5m homes/businesses without power
5.$71Bn in damages
6.NYSE had no power for 4 days, costing $50Bn
7.Crops destroyed for over a year
8.electric network got flooded, costing loads
What were the social impacts of Sandy?
1.Patients had to be evacuated out of hospitals due to power cuts
2.330 deaths, 72 USA rest Carribean
3.350k houses damaged
4.People got PTSD from the storm
How did the US prepare for future Hurricanes?
1.Forecasting
2.Storm resistant buildings
3.Natural barriers
What are the pros/cons of warning from forecasts?
Pro - it is the only way we can predict storms
Cons - Forecasting is very expensive + warning people too late or too early may be hard to judge
What are the pros and cons of storm resistant buildings?
Pros - Will help minimise damage from wind and rain
-less debris after the storm
Cons - All very expensive to setup, and people may not be able to afford it.
What are the pros and cons of natural barriers?
Pros - Good for nature
- cheaper
- protects agains storm surges well
Cons - May need to be created where people live
- prevents development of other buildings
Why is the economic impact of cyclones usually greater in developed countries?
Infrastructure damaged is worth a lot more money
When did Hurricane Sandy happen?
22 october 2012 - 2 november 2012
What are the 2 types of plates?
1.Oceanic - thinner and denser
2.Continental - thicker and less dense
How do tectonic plates move?
1.Radioactive decay of elements in the mantle and core generate heat,
2.When lower parts of the asthenosphere heat up, they become less dense and rise.
3.As they move up, they cool and become denser and sink
4.This creates a circular movement called convection currents.
5.These currents drag the base of the tectonic plates and causes them to move.
What are the 3 types of plate boundaries?
1.Convergent
2.Divergent
3.Conservative
What happens at convergent plate boundaries?
1.At the Ocean+Continental boundaries, the denser oceanic plate is subducted beneath the continental plate, where it melts in the mantle. This then creates volcanoes.
2.At continental+continental boundaries, the ground is folded and forced upwards, creating mountains.
What happens at divergent plate boundaries?
1.the 2 plates are moving away from eachother.
2.Magma then rises from the mantle to fill the gap, creating new crust and shield volcanoes.
What happens at conservative plate boundaries?
1.The 2 plates move sideways past eachother or in the same direction, but at different speeds
2.This causes a lot of earthquakes.
What are pyroclastic flows?
Super heated currents of gas, ash and rock, moving very quick
What are the 2 different types of volcano?
1.Composite
2.Shield
What are hotspots?
- Volcanoes found nowhere near a plate boundary.
- A plume of hot magma moves towards the surface causing pressure to build
- This then breaks through causing an eruption, and making a volcano.
How are composite volcanoes made?
- The oceanic crust gets subducted beneath the continental plate.
- The plate melts, rises and pressure builds.
- This eventually breaks through and causes an eruption and the formation of a shield volcano
What are the properties of composite volcanoes?
1.They have explosive eruptions which are ashy
2.They erupt andesitic lava, which is very sticky and thick. This meant the lava doesn’t flow far and forms a steep cone.
How are shield volcanoes formed?
1.They form at divergent plate boundaries
2.As the plate pulls apart, magma flows out of the hole, making shield volcanoes unexplosive
3.They erupt basaltic lava, which is runny and flows quickly, making a gentle sloped shield volcano
How do earthquakes happen?
- tension builds up between the plates either moving away, towards or past eachother
- The plates then suddenly jolt past eachother, sending out shockwaves - an earthquake
What scale is used to measure earthquakes?
Richter Scale
What is the focus?
The point in the Earth where the earthquake starts
What are shallow focus earthquakes caused by?
Tectonic plates moving at or near the surface. Usually between 0-70km deep
What are deep focus earthquakes caused by?
Crust that has already been subducted into the mantle, moving towards the core, heating up or decomposing. Usually between 70-700km deep
What methods are there to predict earthquakes?
1.Lasers to detect the movement of plates
2.Vibrations can be monitored by a seisometer
3.Gases can be detected from crakcs in the crust before earthquakes
4.Rocks will crack and expand because of the increased pressure
What methods are there to predict volcanoes?
1.tiny earthquakes and changes in shape of the volcano point to an eruption
2.Thermal imaging cameras can be used to detect changesin temp around the volcano to see if they increase
3.analysing the gases escaping from the volcano. If they are sulfurous it can mean an eruption
What long-term planning can be done to prepare a country for tectonic hazards?
1.Emergency services can train and prepare for disasters.
2.Buildings can be designed to withstand earthquakes
3.People should be educated on what to do
4.Evacuation routes hsould be planned
5.Emergency supplies should be stockpiled/
What short term relief is needed after a disaster?
1.Providing food, drink and shelter
2.treating people who have been injured
3.recovering dead bodies
4.resuing people who are trapped or cut off
5.provide temporary supplies of gas, electricity and comms
What preparations did Japan make for tectonic hazards?
1.Strict building laws
2.buildings reinforced with steel frames
3.skyscrapers have deep foundations with shock absorbers to reduce vibrations
4.japan has early warning systems for earthquakes and tsunamis to alert residents.
5.shinkansen immediately brakes during earthquakes
6.Japan has a very educated population, and they regualarly carry out drills.
When was the Tohoku earthquake?
The 11th March 2011
What magnitude was the Tohoku earthquake?
9.0
What were the social impacts of the Tohoku earthquake/tsunami?
- 131k were displaced
- residents suffered from radiation sickness, so 20k were evacuated around Fukushima power plant
- 15,878 people died
- airports were damaged, limiting aid
- 20,000 buildings destroyed
- 2Mn were without power and 2.4Mn without water
- Numerous towns destroyed
- 300k people lived in temp accomodation for weeks
- water supplies were contaminated, but this was controlled quickly.
What were the economic impacts of Tohoku earthquake/tsunami?
1.$300Bn cost - most expensive EVER
2.Economy shattered, overtaken by China earlier than expected
3.20000 buildings destroyed
4.Honda had to shut down production in north east.
5.Infrastructure heavily damaged
6.Ports in Sendai were damaged for weeks, so trade slowed
What were the environmental impacts of the Tohoku earthquake/tsunami?
1.62 landslides lasted for weeks
2.Fukushima power plant went into meltdown and released radiation into local eco-systems
3.Debris pollution everywhere
4.Coastal habitats destroyed, fish are still dodgy near Fukushima - IRRADIATED
What responses did Japan make for the Tohoku Earthquake/tsunami?
1.Search, rescue and Aid(short term)
2.Supporting people(short term)
3.clean up(mid term)
4.building back better(long term)
5.End of nuclear power..?(long term)
6.Improving monitoring and comms(long term)
How did Japan conduct its search and rescue?
1.100,000 members of the Japanese defense force were mobilised
2.Countries like India, Korea, China and the USA sent ait - USA sent an aircraft carrier within 48hrs
Why was the death toll in Japan relatively low?
japan’s buildings are built to withstand earthquakes, and the people are trained to escape tsunamis. Japan also quickly mobilised rescue efforts.
How did Japan support people after the crisis?
1.Makeshift camps were set up quickly and people were checked for disease and radiation
2.These camps were setup quickly, but were still being used 6 months later, which was criticised
How did Japan change the way buildings were built in response to the crisis?
1.Buildings were built with safety glass
2.improved structural reinforcements too
When did the Nepal earthquakes happen?
1.April 2015 - 8.1
2.May 2015 - 7.3
What were the social impacts of the Nepal earthquakes?
1.9000 - high for a country with a small population
2.100k buildings destroyes
What were the major economic impacts for Nepal?
1.Tourism was heavily damaged, this represented a large part of the Nepalese economy
2.35% of GDP was lost
Why type of plate boundary was Japan and Nepal?
both convergent boundaries
What was an environmental impact of the Nepal earthquakes?
Avalanches and landslides disrupted ecosystems
How did Nepal respond in the short term to the earthquakes?
1.Temp housing was provided quickly
2.90% of army was deployed in worst hit areas, but was slowed by damaged infrastructure
3.3 Chinooks were sent by the UK
4.Inflatable hospitals for local people
How did Nepal respond in the long term?
1.India and China gave $1Bn in aid
2.UK gave £73Mn
3.Permanent gov taskforce who check earthquake readiness and public structures
4.People are now being educated to do earthquake drills like JapanJAPANjapanJAPANjapanJAPANNiHOn
