section a:the challenge of natural hazards Flashcards
what is a natural hazard?
A natural hazard is something that happens naturally like volcanoes and earthquakes which have an impact on our society
name tectonic hazards, meteorological, geomorphological
Tectonic hazards-volcanoes, earthquakes, tsunami
Meteorological -snow, wind, flooding
Geomorphological-landslides
name five factors to consider when natural hazards take place
natural factors-geology, topography and relief can all affect both the risk from natural hazards and the severity of the impact
Frequency - how often a hazard occurs. The more times a natural hazard occurs that people will know how to prepare.
Magnitude -the size and scale of the hazard event is linked closely to the risk of poses to people and the environment
Education -countries are usually usually well aware natural hazard. The level of education may reduce the impact and allow more people to survive.
Level of development/wealth -richer countries are more economical developed and have a great wealth and are able to prepare, predict, respond
time-this influence if people are in buildings
Population distribution/density -number of people living in a place and how they spread across an area can affect the severity of the hazard
Geographical-location
How do earthquakes take place?
Earthquakes are distributed on a tectonic plate boundary plate and moving with enormous pressure that builds up and then is released. There is a lot along the west coast of America.
Conservative plate margin
Two plates are moving past each other, there is friction between the plates
Destructive plate margin
two plates moving towards each other, a deep ocean trench forms
Friction -earthquakes
As the plate moves downwards, it melts and moves upwards
Constructive plate margin
move apart, magma forces up and as it breaks through overlying crust, it creates earthquakes and when reaches the surface forms volcanoes
What are the two types of crust?
Continental-relatively light/less dense, cannot be created or destroyed
Oceanic-more dense ,can be created or destroyed
what is a plate margin?
Plate margins are the place where to plates meet there is oceanic and continental plates
describe the distribution of volcanoes in the world
There’s a ring of fire around the Pacific Ocean of volcanoes, there are volcanoes across the West Coast of America
Why choose to live in hazardous areas?
people in poverty have other things to think about on a daily basis
Plate margins are at coastal areas
Building design can withstand earthquakes
Effective monitoring of volcano waves enable people to receive warnings
Fault lines with earthquakes can allow water supply
Fertile soils, rocks for building, rich mineral deposits
Some people may not be aware of the risk
magnitude, epicentre, focus
magnitude – size of earthquake
Epicentre – is the point of the Earth surface directly above the focus
Focus – the point inside the earths crusted where the earthquake originates from
case study-Typhoon Haiyan
primary effects-airport damaged,90% of tacloban was destroyed
secondary effects-infection+disease spread due to contaminated surface and ground water
immediate responses-over $1.5 billion of foreign aid was pledged ,33 countries organized to help
long term responses-no build zone along coast eastern visayas,build back batter
a hurricane forms in the Atlantic. Why does the Caribbean need to worry but not the west coast of Africa
Because the hurricane will spin anticlockwise because of the Coriolis effect making the earth spin. This means it would end up moving towards the Caribbean
give two reason where tropical storms form
There all on sea,because it needs mositure
Tropical storms need heat.Temps of 26.5 degrees this is only found at low lattitudes
explain global atmospheric circulation
Involves a number of interconnected circular air movement called cells
Sinking creates high pressure
Rising air creates low pressure
Surface winds move from high to low pressure, transferring heat and moisture from the one area to another
what are the 4 ingredients for a tropical storm.
1.source of moisture-not on land
2.sea surface temperature of 26.5 to the depth of 50m
3.coriolis effect (earths spin) ——> none at the equator
4.low wind shear —–> wind in the atmosphere are ‘stable’
name in order the cells of the earth
polar cell
ferrell cell
hadley cell
ferrel cell
polar cell
name the tropics of the earth and where
tropic of cancer -north
tropic of capricorn -south
explain v shape valleys and interlocking spurs
upper coarse of a river
Spurs are formed as a result of the river trying to find the fastest way down towards the sea.
The land and forms around the waterways which is why there is spurs around the river
it erodes vertically 
what causes an earthquake
earthquakes are the sudden violent shaking of the ground.
They happen because the earths plates are consistently moving.
Sometimes because of friction plates try to move and become stuck.
Pressure builds up and because of the plates are still trying to move when the pressure is released.
It sends out a huge amount of energy causing the Earth surface to shake. 
how can monitoring reduce the risk from tectonic hazards?
Remote sensing – satellites detection and changes to the shape of volcanoes
seismicity-seismographs record earthquakes
Round deformation – laserbeam’s form shape changes
Geophysical measure measurements – detect change in gravity
Gas – detect gas release as magma rises
Hydrology– measurements of gas dissolved in water
how can prediction help reduce the risk of tectonic hazards
volcanoes – based on scientific volcano eruption
Earthquakes – historical records of plate margins have identified locations they believe that are at greater risk
how can protection reduce the risk from tectonic hazards?
volcanoes – earth embankment are explosives to divert lava flows away from poverty
Earthquake – construct buildings and bridges to resist the ground shaking. Like concrete columns strengthened by a steel frame.
Earthquake drills
How can planning reduce the risk from tectonic hazards?
volcanoes – hazard maps have been produced for worlds most dangerous places. Can be used to restrict certain land uses.
Earthquakes – maps can be produced to show effect of earthquake and identify at risk areas
why is the UK weather like it is?
The atmospheric circulation system means that the UK sit just below the 60° N which puts the UK in the boundary of cold polar air moving down from the north and warm subtropic air moving from the south

Describe the first two stages of atmospheric circulation
Air and sinks creating a belt of high-pressure and cold dry climate
At about 60° N and S cold polar air mixes with warmer air and rises, creating a belt of low pressure
describe the 3rd and 4th stage to atmospheric circulation
cool air sinks , creating a belt of high-pressure. As it sinks it becomes warmer and drier
warm air rises, creating a belt of low pressure. As the air rises, it cools.
Clouds form and then release precipitation. Above the air will eventually separate and move to higher latitudes. 
describe the 5th and 6th stage to atmospheric circulation
suns heat is concentrated
suns heat is spread out
What is the evidence for climate change?
shrinking glaciers
Rising sea levels
Seasonal change
Temperature record records
how do we know the climate is changing?
Tree rings – rings found in a tree trunk can tell us the age
Ice car – ice sheet glaciers. The tiny bubbles within the ice.
How can we manage the effect of climate change?
alternative energy – 87% of all human produce CO2 emissions are the burning of fossil fuels. To help reduce carbon emissions we could use hydroelectric electricity.
Carbon capture – coal is the most polluting of all fossil fuels. Carbon capture and Storage uses technology to capture CO2 produced. Once captured the carbon gas is compressed and transported by pipeline to an injection well.
Planting trees – trees at his carbon sinks, removing CT from the atmosphere by the process of photosynthesis
