Natural Hazards

Question 1

Hazard risk

Answer 1

The probability a hazard may take place.

Question 2

Hazard perception

Answer 2

Hazards need to be reacted to in different ways. People process and receive information differently.

Question 3

Geophysical hazard

Answer 3

Disasters brought about by tectonic snd seismic activity below the Earth’s surface. Linked to land movement.

Question 4

Factors influencing hazard perception: cultural

Answer 4

. Part of daily lives
. Lives linked to hazards e.g. geothermal energy in Iceland
. People perceive risk differently - individual culture

Question 5

Factors influencing hazard perception: Economic

Answer 5

. Developed parts people are educated
. Some then think it’s worse than it is - alters hazard perception
. MIC’s exposed to many news reports on latests hazards skewing view
. Risk vs reward e.g. fertile soil + poor have less possessions
. Lack of perceived danger in LICs, less prepared + lack education
. HIC’s have adapted to mitigate risk

Question 6

Avalanche

Answer 6

. Slide of a large snow (or rock) mass down a mountainside
. Caused when a build-up of snow is released down a slope
. One of the major dangers faced in the mountains in winter

Question 7

Mudflows

Answer 7

. Type of landslide
. Heavy rainfall causes loose soil on steep terrain to collapse and slide downwards
. Lahars are related

Question 8

Flood

Answer 8

. Result of prolonged rainfall from a storm, rapid melting of snow, or rivers which swell from excess precipitation upstream and cause widespread damage to areas downstream, or the bursting of man-made dams or levees.
. Tropical cyclones can result in extensive flooding and storm surge.

Question 9

Landslides

Answer 9

. Related to an avalanche, but instead of occurring with snow, it occurs involving actual elements of the ground, including rocks, trees, parts of houses, and anything else which may happen to be swept up
. Landslides can be caused by earthquakes, volcanic eruptions, or general instability in the surrounding land.

Question 10

Wildfire hazard

Answer 10

. Uncontrolled fire burning in wildland areas
. Common causes include lightning and drought
. Can be started by human negligence or arson
. Threat to those in rural areas and also wildlife
. Can produce ember attacks, where floating embers set fire to buildings at a distance from the fire itself.

Question 11

Cyclonic storms

Answer 11

. Hurricane, tropical cyclone, and typhoon are different names for the same phenomenon
. System that forms over the oceans
. Caused by evaporated water that comes off of the ocean and becomes a storm
. Hurricane is used in the Atlantic and eastern Pacific Oceans
. Tropical cyclone in the Indian, typhoon in the western Pacific.

Question 12

Tornado

Answer 12

. Natural disaster resulting from thunderstorm
. Tornadoes are violent, rotating columns of air
. Can blow at speeds between 50 and 300 mph (480 km/h)

Question 13

Lahars

Answer 13

. Related to a volcanic eruption
. Involves a large amount of material, including mud, rock, and ash sliding down the side of the volcano at a rapid pace
. Usually associated with heavy rains
. Flows can destroy entire towns in seconds and kill thousands of people.

Question 14

Earthquake

Answer 14

. Caused by the ground shaking or moving sideways

. Most occur along the edges of tectonic plates

Question 15

Volcanic eruption

Answer 15

. Point at which a volcano is active and releases its power
. Volcanoes, like earthquakes occur along tectonic plates
. Some form pyroclastic flows which are high temperature clouds of ash and steam that can trial down mountainsides at speed exceeding an airliner.

Question 16

Tsunami

Answer 16

. Wave of water caused by the displacement of a body of water
. Can be caused by undersea earthquakes e.g. 2004 Indian Ocean Earthquake, or by landslides e.g. Lituya Bay, Alaska.

Question 17

Mitigation

Answer 17

. Action taken to reduce/eliminate the threat to property/life as a result of a natural hazard
. Includes ideas of adaptation and preparation + anything done on an individual level to reduce the impact of a hazard
. Any mitigation carried out needs to go through a cost-benefit analysis to ensure that it is economically viable

Question 18

Management

Answer 18

. Most hazards little can be done to prevent the hazard itself
. Range of ways we can manage ourselves + property to minimise the chance of damage
. The degree of management depends on the wealth of a nation
. Japan spends billions of pounds on its tsunami warning systems, whilst the Philippines relies on basic weather reports and wrapping belongings in cling film
. Shows great disparity in how nations at different stages of development can manage hazards
. Despite management little that can be done for some hazards e.g. Volcanic ash falls + wild fires.

Question 19

Fatalistic approach

Answer 19

. Russian roulette - an optimistic approach
. Some communities say that hazards are ‘God’s will’.
. Populations take direct action that is concerned with safety.
. Losses are accepted as inevitable.
. People may remain where they are.
. Lack of alternatives - due economic reasons.
. Used to experiencing the hazard
. Lived through events many times

Question 20

Risk sharing

Answer 20

. Problem shared is a problem halved
. When a natural hazard event occurs somebody always loses out
. Rather than it just being a single individual or company, risk-sharing works spreads the risk reducing any one group/individual’s risk making it more acceptable
. Risk sharing may also involve spreading the financial burden imposed by possible management or adaptation strategies so more elaborate and expensive ideas can be put in place.

Question 21

Prediction

Answer 21

. Knowing when + where a hazard will occur is advantageous and can lead to significantly improves chances of a reduced death toll
. As such human response to a hazard is often to try and predict when and if a similar hazard may occur again.
E.g:
• Seismic monitoring of areas around volcanoes
• Measuring gas emissions from active volcanoes and considering concentrations
• Satellite observation of weather systems (e.g. Hurricanes/Typhoons) to monitor their strength and potential storm track
• Geological ground changes as a precursor to an earthquake
• Odd animal behaviour around a plate margin prior to an earthquake
. Methods only worthwhile if the information is acted upon and not ignored

Question 22

Adaption approach

Answer 22

. When a town or a city starts to change their way of living to fit natural disasters into their everyday lives
. Building structures, the types of research done and the way governments react are the main things that change
. This is as buildings are tweaked with new designs to outstand any natural disasters, and more specific research is done on predicting when natural disasters might occur and governments act differently due to past experiences
. Following the 2010 Christchurch earthquake the government have conducted a review of old buildings and retrofitted many of them with internal supports to minimize the chance of collapse in a future tectonic event.