Natural Hazards Flashcards
Give the definition of a hazard
A danger or risk
Give the definition of a natural hazard
A geophysical event that affects the physical environment and people
Give the definition for disaster
An event that causes damage or loss
Features of inner core
Solid, provides heat, made of iron and nickel
What is the mantle made of?
molten magma
What are the two types of plate?
Oceanic and continental
Give the order of the earths insides,starting from the middle.
Inner core, outer core, mantle crust
Where is Haiti?
Central America, in continent of North America, on island in Caribbean, west end of island is Haiti and the rest is the Dominican Republic
Is it smooth?
No, there is friction between the two plates and extreme stresses build up in crustal rocks, when pressure is released earthquake happens
What way do the Caribbean and North American plates move?
Caribbean = from west to east N.A = east to west
Give the definition of subduction
One plate going under the other
What does the size of the earthquake relate to?
The frequency of the movement if there is a long period without movement the pressure builds up and the eventual movement will be greater generating more energy and a higher magnitude earthquake there had not been a very large earthquake at this plate boundary for over 40 years
Why do tectonic plates move?
because they float on the mantle. The mantle moves due to convection currents: hot rocks rise, give off some heat and then fall. This creates big swirls of rock under the crust of the earth, which moves the plates of crust on top.
How do earthquakes occur on conservative plate boundaries?
They slide against each other and no plate is created or destroyed because there is no Magma or subduction. Therefore, volcanoes do not occur at conservative plate boundaries.
How do earthquakes occur on constructive plate boundaries?
Occurs when plates move away from one another. Volcanoes are formed as a result of the magma filling the gap created by the plates
How do earthquakes occur on destructive plate boundaries?
When oceanic plate and continental plate move together. Oceanic plate moves under continental plate. Friction may cause earthquakes. Magma rises up through the cracks.
Explain two human reasons why so many people died in the 2010 Haiti earthquake
66% of population make less than £1 per day
Shortage of doctors people die from broken limbs
1-15 people live in cramped conditions and poor housing
300000 people live in cité soleil where there are no pavements or sewers or electricity
Haiti earthquake 2010 social impacts
3mil people affected 220,000 deaths 300,000 injured 1.3mil homeless Several hospitals collapsed
Haiti earthquake 2010 economic impacts
30000 commercial buildings destroyed
Businesses destroyed
Main clothing industry damaged
Airport and port damaged
What is a hurricane?
A hazard that brings heavy rainfall, strong winds, and related hazards (mudslides, floods)
In Central America they are called hurricanes
In Pacific and China sea they are called typhoons
In Bangladesh Pakistan India Australia they are called cyclones
What does a hurricane need to happen?
Needs tropical water, so it can form on planet earth between 8 to 20 degrees latitude
High humidity, light winds
Sea surface needs to be 26.5 degrees or more
Hurricane season in northern hemisphere runs through June to November
How does a hurricane form?
- Warm ocean heats air above which rises quickly
- The rising air evaporates and starts to spin anti-clockwise in the northern hemisphere
- As the air rises it cools and forms cumulonimbus clouds ☁️
- The rapidly rising air creates areas of low pressure which suck in air causing strong winds
- Once it goes on land it slowly dies
What does the Saffir-Simpson scale measure?
Saffir-Simpson Scale is the way we measure hurricanes. It measures wind speed and storm surge height
Name two impacts of 2013 typhoon haiyan
Economic impacts
The overall economic impact of Typhoon Haiyan is estimated at $5.8 billion (£3.83 billion).
Six million workers lost their sources of income.
Major rice, corn and sugar-producing areas for the Philippines were destroyed affecting the country’s international trade and farmers’ incomes.
Tacloban’s city airport was severely damaged, affecting business and tourism.
Fishing communities were severely affected with the storm destroying 30,000 boats and associated equipment.
Social impacts
More than 7,000 people were killed by Typhoon Haiyan.
1.9 million people were left homeless and more than 6,000,000 displaced.
There were outbreaks of disease due to the lack of sanitation, food, water, shelter, and medication.
Less affected areas reported that their populations more than doubled after the typhoon with the influx of refugees.
The Tacloban city government was devastated, with only 70 people at work in the immediate days after the disaster compared to 2,500 normally. Many were killed, injured, lost family or were simply too traumatised to work.
In the city of Tacloban, widespread looting took place in the days following the typhoon.
Environmental impacts
Widespread floods damaged and in many cases destroyed homes and businesses in coastal areas.
The Philippine government estimated that about 71,000 hectares of farmland was affected.
Thousands of trees were uprooted leading to a massive release of carbon dioxide and loss of habitat with resulting effects on wildlife.
Flooding knocked over Power Barge 103 causing an oil spill affecting mangrove ecosystems.
Major roads were blocked by trees, and were impassable.
Two impacts of hurricane sandy
Economic impacts
Hurricane Sandy was the second most costly hurricane on record, causing $71 billion in damages. In New York City, economic losses are estimated at exceeding $18 billion.
Buildings, cars, people’s possessions and business stock were lost.
More than 18,000 flights were cancelled leading to disruptions in business, tourism and trade.
Crops were lost resulting in loss of earnings for farmers.
Social impacts
At least 286 people were killed either directly or indirectly by Hurricane Sandy. There were 147 direct deaths: 72 in the USA and the rest mainly in the Caribbean, including 54 in Haiti and 11 in Cuba.
Power failure at New York University Langone Medical Centre led to the evacuation of all 215 patients to other hospitals.
People were highly stressed and anxious. In the longer term, many people could be affected psychologically by the loss of family and friends.
More than 8.5 million homes and businesses were left without power.
In Washington DC and other cities, many supermarkets ran out of essentials such as bottled water and batteries as people prepared for the worst.
The New York City marathon was cancelled resulting in a loss of income for many businesses.
Environmental impacts
346,000 houses were damaged or destroyed in New Jersey and 305,000 damaged or destroyed in New York.
Makeshift shanty towns in Haiti were washed away.
Fallen trees and flooded vegetation affected animals’ habitats.
In areas such as New York and New Jersey, untreated sewage was washed into public drinking water, threatening human health.
More than 70 per cent of crops, including bananas and maize, were destroyed in the south of Haiti.
Roads, train lines and other transport infrastructure became unusable due to flooding, resulting in disruptions to travel and trade.
Approximately 10 metres of beach was lost in some parts of New Jersey (making it narrower), exposing the coast to further erosion and impacting wildlife.
Why did the Philippines suffer more than nyc after tropical storm?
Low Income Country (lic) means cannot recover financially from damage as quickly meaning that they cannot restructure buildings and have a full recovery as quickly as a rich city like New York can
