Natural Geog cards

Mount Etna, Italy- case study

-This case study is concerned with how governments use different strategies to help prevent or reduce the impact of a volcanic eruption, and also why people still live in areas at risk of being affected by a serious volcanic incident. 

-In 1983 there was an eruption on Mount Etna, the impact of which was reduced by lava diversion barriers and by cutting a diversion channel for the lava to run down.

-The key thing done at Mount Etna to reduce the impact when a volcano does hit is land use zoning where the Italian government has already designated the land surrounding Etna into 6 different hazard zones, with 1 being the least impacted area and 6 the most. By dividing land up in this way the government can pritoritise areas that need protection or relief most urgently.

-There are a number of reasons people continue to live in the area surroudning Mt. Etna. Geothermal energy can be harnessed from underground for cheap energy, the areas surrounding volcanoes often contian some of the richest and most fertile soil in the world ideal for farming, deep in the earth surrounding volcanoes are often incredibly valuable  minerals including gold and silver etc., and finally volcanoes are huge tourist attractions which provides money for locals and local businesses.

Philippines (LEDC), Southeast Asia-case study

-This case study is concerned with multi-hazard zones and how some countries are vulnerable to multiple hazards. An example being the Philippines a country over 7000 islands and 100 million people in SE Asia. The Phillipines experiences volcanoes, earthquakes and tsunamis. 

-The country is estimated by the WRI (World Resources Institute) to be the 3rd highest risk country in the world. The World Bank estimates 60% of land and 74% of the pop. are vulnerable to two or more hazards. 

-The problems caused by the natural hazards are exascerbated by the lack of infrastructure and prevention or reduction strategies in the country because of a lack of money. And lack of education for the population.

-The country is home to 18 active volcanoes as it is located on the Pacific 'Ring of Fire' where there is subduction of the Philippines plate and Sundra plate. Volcanoes are a common hazard. 

-Being based on a plate boundary the country has experienced numerous earthquakes in recent years with the most serious being an earthquake in 1976 that resulted in the deaths of 6000 people. 85% of these deaths were caused by a huge tsunami that was triggered by the earthquake which is a further hazard that exists in the Philippines. 

Mount Eyjafjallajökull (Eyjaf), Iceland-case study

-This case study is concerned with with how tectonic hazards can have impacts on a global scale. 

-In 2010 Mt. Eyjaf erupted in Iceland releasing an ash cloud of 110 million m3 to a height of 9km in the air. The ash cloud meant that most flights in Europe were cancelled for a period of time leading to massvie global ramifications.

-During this time disruption caused to tourism and business led to economic impacts totalling over $3bn. Airports lost $200m per day, whilst the company British Airways lost $26m per day. 

-The lack of flights meant UK music bands could not get to California for a festival, toursits were stranded away from home, perishable Kenyan agriculutral products in the UK perished with Kenyan flower imports losing $2m per day, fresh fish from Iceland quickly had to be cold stored, and car parts could not reach factories around Europe resulting in BMW shutting their production lines down for a week. 

-Sporting events were also affected as FC Barcelona were forced to travel to a European away game by coach rather than plane, and a Moto GP race to be held in Japan was postponed as European based teams could not travel to the Grand Prix. 

Sendai earthquake and tsunami, Japan (MEDC), 2011

-This case study is concerned with showing the impact tectonic hazards can have on MEDC's. 

-In 2011 an earthquake that scored 9.0 on the richter scale hit around 50 miles off the east coast of Japan and the city of Sendai. The huge earthquake led to a massive tsunami with a wave reaching up to 40m.

-Despite being an MEDC with several plans in place after the Kobe earthquake 1995 including retrofitting on buildings, education for the population and many early warning systems. However, the sheer scale of the earthquake and tsunami in 2011 meant that just under 16,000 people were killed, with around 6,000 injured. 

-According to the World Bank the disaster was the costliest in history resulting in damages of $235bn .

-Alongside the earthquake and tsunami the result of this was also disastrous floods, fires and landslides.

Haiti Earthquake and tsunami (LEDC), 2010

-This case study is concerned with the impact of tectonic hazards on an LEDC. In 2010 an earthquake with a magnitude of 7.6 on the richter scale hit the land just off the capital, Port-Au-Prince. This earthquake triggered a smaller localised tsunami despite the epicentre being on land.

-Haiti is an incredibly poor country with the majority of people living in densley populated towns and cities in shacks where deadly debris was a big problem. Also there is an incredibly poor infrastructure meaning there were little emergency services to respond, there was no education on what to do for the population, there was no management plan or prevention strategies, and finally no aid to be provided by the govt.

-It is estimated that around 160,000 people were killed, over 250,000 buildings destroyed, the country was brought to a standstill of devastation as most govt. buildings were destroyed including hospitals and overwhelming many clothes factories were destroyed of which 60% of Haiti's wealth relies on.

-The international communities response was co-ordinated by the UN and the USA, the UK contributed £20m with many other countries and organisations such as the USA and the EU also contributed large amounts of money to the relief effort, doctors, medicines, and also supplies such as food and water.

Pressure and Release model

-The Pressure and Release model suggests what should be tackled in order to reduce the risks of a disaster.

Different types of plate boundaries

Conservative- This is where 2 different plates slide by each other in the opposite direction or in the same direction at different speeds. When the friction is overcome the 2 plates give a sudden jolt past each resulting in an earthquake. An example of where this happens is the San Andreas fault, California, USA.

Constructive- This is where 2 plates move apart in opposite direction leaving a gap in the earth where the 2 plates have pulled apart. Magma then rises up through the gap and cools forming new crust and volcanoes. An example of where this type of boundary occurs is the Mid-Atlantic ridge.

Collision- This is where 2 continental plates collide into each other but neither is subducted under the other so both are forced up and form fold mountains. An example of this is the Himalayan mountain range.

Destructive- This occurs when an oceanic plate and a continental plate collide, with the heavier oceanic plate subducted under the lighter continental one. The friction caused leads to the oceanic plate melting and triggering earthquakes, additionally this plate boundary also forms earthquakes as magma rises up through cracks in the surface. An example of this is where the Nazca plate meets the South American plate.

Hotspots- A hotspot can occur anywhere on a plate and is formed when one area of mantle is hotter than all the rest of the mantle. An example of where this occurs are the islands of Hawaii.

Volcanic hazards with case studies

Chances Peak, Montserrat, 1997- This case study is an example of the danger caused with volcanoes where there are pyroclastic flows as the city of Plymouth was completely destroyed. 

Mount Pinatubo, Philippines, 1991- This case study is an example of the danger caused by volcanic gas as it is 70-90% water vapour so can be evaporated but also may contain sulphur dioxide as it did at Mt. Pinatubo which destroyed all the local land. 

Nevado del Ruiz, Colombia, 1985- This is an example of lahars where water from heavy rainfall or a glacier is mixed pyroclastic flow to create a deadly mix, in Colombia in 1985 it led to the deaths of 23,000 people. 

Middle East, tectonic vulnerability case study

-The Middle East is an area of intese seismic activity and is highly vulnerable.

-Many people from this area lack knowledge and understanding of the tectonic situation and how to be prepared which can have disastrous results. After the 2003 Bam earthquake over 31,000 people died in Iran because they lived in houses of clay poorly designed to withstand earthquakes.

-Turkey in the Middle East also has these problems because although for many years a culture of retrofitting was built up in the building industry, rapid urbanisation has changed this as instead of using costly and time consuming local techniques, buildings have quickly been put up using cheap concrete. 

-Turkey is particularly vulnerable because it lies on the highly active Antolian fault which is making its way from east to west and eventuallly will strike the megacity of Istanbul.