section a:the challenge of natural hazards

Question 1

what is a natural hazard?

Answer 1

A natural hazard is something that happens naturally like volcanoes and earthquakes which have an impact on our society

Question 2

name tectonic hazards, meteorological, geomorphological

Answer 2

Tectonic hazards-volcanoes, earthquakes, tsunami

Meteorological -snow, wind, flooding

Geomorphological-landslides

Question 3

name five factors to consider when natural hazards take place

Answer 3

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

Question 4

How do earthquakes take place?

Answer 4

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.

Question 5

Conservative plate margin

Answer 5

Two plates are moving past each other, there is friction between the plates

Question 6

Destructive plate margin

Answer 6

two plates moving towards each other, a deep ocean trench forms

Friction -earthquakes
As the plate moves downwards, it melts and moves upwards

Question 7

Constructive plate margin

Answer 7

move apart, magma forces up and as it breaks through overlying crust, it creates earthquakes and when reaches the surface forms volcanoes

Question 8

What are the two types of crust?

Answer 8

Continental-relatively light/less dense, cannot be created or destroyed
Oceanic-more dense ,can be created or destroyed

Question 9

what is a plate margin?

Answer 9

Plate margins are the place where to plates meet there is oceanic and continental plates

Question 10

describe the distribution of volcanoes in the world

Answer 10

There’s a ring of fire around the Pacific Ocean of volcanoes, there are volcanoes across the West Coast of America

Question 11

Why choose to live in hazardous areas?

Answer 11

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

Question 12

magnitude, epicentre, focus

Answer 12

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

Question 13

what is the four way of reducing the risk from tectonic hazards?

Answer 13

Monitoring – satellites detect heat and change of the shape of volcanoes,seismicity record earthquakes, ground formation, geophysical measurements, gas

Prediction
volcanoes, – based on scientific volcano eruption
Earthquakes – historical records of plate margins have identified locations they believe that are at greater risk

Protection
Volcanoes – earth and embankments are explosives to divert lava flows away from poverty
Earthquakes – building and bridges to restrict the ground shaking. Like concrete columns strengthened by a steel frame, earthquake drills.

Planning
Volcanoes – hazard maps have been produced for worlds most dangerous places.
Can be used restrict certain land uses
Earthquakes – maps can be produced to show effects of earthquake and identify at risk areas

Question 14

case study-Typhoon Haiyan

Answer 14

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

Question 15

a hurricane forms in the Atlantic. Why does the Caribbean need to worry but not the west coast of Africa

Answer 15

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

Question 16

give two reason where tropical storms form

Answer 16

There all on sea,because it needs mositure

Tropical storms need heat.Temps of 26.5 degrees this is only found at low lattitudes

Question 17

explain global atmospheric circulation

Answer 17

Air from the equator rise and moves towards the poles,then cools down and sinks at approximately 30 degrees latitude north and south of the equator.

The sinking air creates an area of high pressure with very little rainfall.

Some of the air moves back to the equator as surface winds called trade winds.

Question 18

what are the 4 ingredients for a tropical storm.

Answer 18

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’

Question 19

name in order the cells of the earth

Answer 19

polar cell
ferrell cell
hadley cell
ferrel cell
polar cell

Question 20

name the tropics of the earth and where

Answer 20

tropic of cancer -north
tropic of capricorn -south