Topic 1Hazardous Earth Flashcards
What is global atmospheric circulation
The movement of air around the planet
Describe low pressure zones
As air warms it rises leading to low pressure on the surface
Describe high pressure
As air cools it descends leading to high pressure on the surface
Why does air subside at the poles
The loss of energy at the poles creates very cold air that subsides towards the surface
How does temperature and rainfall change when moving from the equator to the poles
Temperature decreases directing to the poles as it recieves less sunlight and nearer to the equator more water is evaporated leading to more rainfall aswell
What is the source of global atmospheric circulation
The rotation of the earth and the amount of heat different parts of the globe recieve
What are some features about winds of high pressure locations
Winds tend to be light and rotate in a clockwise direction
What are the three cells in the hemisphere called
The Hadley, Ferrel and polar cells
What direction does winds blow (pressure zones)
Winds blow from areas of high pressure to areas of low pressure transferring heat away from the equator
What do ocean currents do
Ocean currents have a large scale movement of water that transfers heat energy from warmer to colder regions
What do surface currents do
They help transfer heat awat from the equator and are caused by winds
What are 4 different natural factors that have caused natural climate change
Volcanic eruption/asteroid strikes, fluctuations in solar radiation, tectonic shifts, slight changes in our orbit
What are orbital changes and what do they cause
Variations in the way the earth moves around the sun. This may cause glacial and inter-glacial cycles during the quaternary period
What is axiel tilt and what can it cause
The earth doesnt sit with the north and south poles perfectly and the earth is tilted at 23*, over long periods of time the angle slightly changes which the earth might be tilted further away from the which exagerates the difference in seasons, and the same the other way.
What is precission (wobble)
The earth does not rotate perfectly on its axis and it wobbles, because of this the direction the axis is facing slihhtly changes. This creates either greater or smaller changes in seasons between summer and winter
How is the emission of dust and ash important when volcanic erupitions and asteroid strikes occur
When large volumes of dust gets ejected into the atmosphere it blocks solar radiation which can lead to glacial periods. The blanket of ash and gas will prevent sunlight reaching the earths surface and reflects sunlight back into space
What are sun spots
Black areas in the sun’s surface, if there are more black spots this tells us the sun is more active. Lots of black spots mean more solar energy being fired out from the sun towards earth making the earth warmer
What are ice cores and how do they help us infer previous temperatures
The ice contains bubbles of the air from each year. The bubble in each layer represents how much CO2 they contain. We can learn about the temperatures fir each year by measuring relative amounts of different types of oxygen atoms in the water
What are tree rings and how do they help tell us abiut previous climates
Each ring shows one year of growth. Chnage sin shape and size of tree rings can show conditions during that year. Warmer and wetter weather is shown with bigger rings. Cool and drier weather is shiw by thinner rings
How can histricial evidence help tell us about previous climates
Old photos, drawings, diaries and writtens records. These souces are often not very acurate becauss they were not intended to record weather however they do give us some information
What are convergent plate boundaries
Where two plates move towards each other
What are conservative plate boundaries
Plates are mobing sideways of eachother
What are divergent plate boundaries
To plates moving away from eachtoher
Where do composite volcanoes occur
Convergent plate bpundaries
Where do shield volcanoes occur
Occur at divergent plate boundaries
How does farming increase global warming
Farming of livestock releases lots of methan, cows farting.
How does industry increase global warming
Industrial processes release greenhouse gasses. When cement is produced it relases CO2
What temperature do tropical cyclones develop at
26.5C or higher
What causes winds
Differences in air pressure
What way do winds move
High pressure zones to low pressure zones
What are high pressure zones
Cool declining air
What are Low pressure zones
Warm ascending air
At 30° north and south of the quator what is the air pressure
High pressure zone
What are trade winds
Surface winds that blow towards the equator
What are westerlies (winds)
Winds that blow towards poles
At 60° north and south of the equator what are the pressure zones
Low pressure zones
What pressure zones are both poles
High pressure zones
What causes surface currents
Winds
What do surface currents do
Transfer heat from the equator to cooler regions
What are deep ocean currents caused by
Differences in water density
What happens to the air when ferrel nd hadley cells meet
Air skins creating high pressure belt
How does pressure affect levals of rain fall
High pressure - low rainfall
Low pressure - high rainfal
What are the conditions in tropical climate zones
High temperatures
High rainfall
What is the name of the most recent geological period that started 2.6millions years ago and is still active today
Quaternary period
How long do galcial periods roughly last for
100,000 years
How long do interglacial periods roughly last for
10,000 years
What are the 4 different sources that show evidence of cilimate change
Tree rings
Ice cores
Temperature records
Pollen analysis
Exaplain the distribution of short and long wave radiations from from the sun and earth.
The incoming energy from sun is called short-wave radiation
The outgoing energy from the earth is long-wave radiation
What do gases in the atmosphere do. (Greenhouse effect)
They naturally act as an insukating layer. They let short-wave radiation in but trap long-wave radiation helping to keep the earth at rhe right temperature. This is called greenhouse effect
Give two examples of greenhouse gases
Carbon dioxide and methane
What is the enhanced greenhouse effect
The proccess of which humans activites causing global warming by making the greenhouse effect stronger
How does farming enhance the greenhouse effect.
Farming of livestock produces a lot of methane due to cows farting
Explain one way in which industries enhance the greenhouse effect
Industrial waste may end up in landfill sites where it decays. This release methane
Give one way fossil fuels enhance the green house effect
Foosil fuels like coal,oil and natural gas are burnt at power stations (for example) which releases CO2.
Explain one way how transportation increases greenhouse effect
Most cars, lorries, ships and planes use fossil fuels to function which releases CO2 when burnt.
Give 4 factors that show how humans are causing global warming
Declining arctic ice
Global temperature rise
Seal level rise and warming oceans
Extreme weather events
What are 3 impacts of climate change
More money has to be spent on predicting extreme weather events, reducing their impacts and reversing them
Low lying coastal areas could be lost by flooding
Areas could become too hot and dry for people to live in. This will force people to leave and overcrowed in other cities/countries.
What is the most common location in terms of distance from equator are tropical cyclones formed
Between 5 and 30° north and south of the equator
What is the centre of the tropical cyclone called
The eye
What does dissipate mean
Lose strength
How fast do winds reach in the eye
Up to 50km
What are 4features of the eye in the tropical cyclone
light winds,
no clouds,
no rain,
high temperature
What is the eye surrounded by in a tropical cyclone
Eyewall
What are 4 features of the eye wall
Strong winds
Storm clouds
Torrential rain
Low temperature
What are the 3 physical hazards tropical cyclones cause
High winds
Intense rainfall
Storm surges
Coastal flooding
Landslides
What are 3 impacts tropical cyclones cause on people
People may drown in string currents created by floodwater
People can become homeless due to the winds destroying the buildings
People may die to the debris carried by the floodwater
Cholera possibilites increase due to sewage overflowing contaminating water supplies
Unemployment increases due to buisnesses getting damaged or destroyed
What are 3 impacts tropical cyclones cause on the environment
Trees are uprooted by high winds which can damage or detroy habitats
Storm surges can erode beaches
Flooding caused by storm surges can pollut freshwatee environments with saltwater
Landslides deposit sedimwnr in lakes which can kill ocean life
Flooding can damage industrial buildings which can cause chemicals to leak into the environment
What are the 3 different ways to prepare and respond to tropical cyclones
Forecasting
Evacuation
Defences
How does forecasting prepare for tropical cyclones and whybis it important
Scientists can use satelties to predict when and where tropical cyclones will hit land. This gives people more time to evacuate and protect their homes/buisnesses. e.g boarding up windows.
Why is evacuation important when minimising impacts from tropicsl cyclones
Evacuations can reduce number of deaths and injuries. To help this goverments csn plan evacuation routes to get people away from storms quickly
How does defences minimise risks of tropical cyclones and why are they important
Defences like sea walls can prevent the damage from storm durges and houses can be built on stilts to stay safe from floodwater. This will reduce number if houses destroyed so fewer people will be killed and made homeless.
What was rhe magnitude of hurricane katrina
Category 3
How many people were killed in hurrican katrina
More than 1800
How many houses were destroyed in hurican katrina
300 000 houses
Describe the preperation of hurikane katrina (developed country). Was it successful?
The USA had a monitoring system (NHC) to predict when are where the hurricsne would hit using satelites. 70-80% of the people in New Orlands evacuated before the hurricane reached land reducing the number of people killed
How many people died from cyclone nargis
140 000 died
How many houses were destroyed in cyclone nargis
450 000 were destroyed
Describe the preperation if cyclone nargis (developing country). Was it succesful?
Myanmar didnt have a good monitoring centre for cyclones this meant indian weather angencies only warned myanmar 48 hours before the cyclone hit. Warnings were issued on Tv and Radio but didnt reach the people in poor communities. The country had no evacuation plans and due to all of this more people were killed. Not succesful.
Describe the order in the earths sturtcure from middle to ourside
Inner core, outer core, mantle, crust
What does the temperature range from inside the core
4400-6000°C
What is the core made out of
Iron and nickel
What is the mantle made up of
Silicon-based rocks
What does the temperature of the mantle vary from
From 1000 to 3700°C
What is the crust made up of
Silicon based rocks
What are the two types of crusts called
Continental and oceanic
Compare oceanic and continental crusts
Continental crusts are thicker and less dense
Oceanic crusts and thinner and more dense
What is the process that moves tectonic plates
Convection currents
What are different names for the crust and mantle
Lithosphere
Asthenosphere
Describe the peoccess of convection currents
When lower parts of the asthenosphere (mantle) heat up, they become less dense and slowly rise. As they move towards the top of the mantle the cool down and become more dense causing them to sink. These cricular movements of semi-molton rock are called convection currents.
At what plate bondaries are volcanos found at
Convergent and divergent plate boundaries
What happens when an oceanic and continental plate meet at a convergent plate boundary
The denser oceanic plate is forced down into the mantle and destroyed creating volcanos.
What happens when two continental plate boundaries meet
The ground is folded and forced upwards which chreates mountain ranges
What happens at divergent plate boundaries
Plates move away from eachother and magma rises from the mantle to fill the gap and cools creating new crust
Where are hotpsots found
Away from poate boundaries
What are hotpsots and how do they occur
When a large amount of hot magma from the mantle moves towards the surface causing an unusal floe of heat from the mantle to the crust. Sometines the magma can break through the crust and reach the surface causing an eruption and a volcano
What are the two different types of volcanos
Conposite volcanos
Shield volcanios
3 features of a composite volcano
Steep sides
Explosive eruptions
Thick and sticky lava
3 features of a shield volcano
Low flat sides
Not explosive
Runny lava
At what plate boundaries do earth quakes occur
All plate boundaries
What are earthquakes measured in
Moment magnitude scale
What is the focus of an earthquake
The point at which the earthquake starts
Why do deep-focus earthquakes have a lower magnitude than shallow-focus earhquakes
Deep-focus earthquakes’ shockwaves have to travel through more rock to reach the surface which reduces the energy they carry to the surface
What is the epicentre in tsunamis
The point durectly above the focus
Give 3 short-term reliefs developed countries will do after a disaster like an earthquake
Recover dead dead bodies to prevent spread of disease
Rescuing people still alive who are trapped due to collaps builds, roads or bridges
Treating injured people to prevent more deaths
What are primary impacts
Immediete impacts of the hazard
Give an two primary impacts of an earthquake
Builds collaps/damages
Roads get destroyed
Gice two possible secondary impacts of an earthquake
Earthquake causes a tsunami
People becoming homeless due to destroyed houses
How can scientists predict an earthquake
Lasers can be used to detect the mobement of tectonic plates before an earthquake
How can scientists predict volcanos
Thermal imaging cameras can be used to detect changes in temperature around the volcano. Temperature increase before a volcano.
