620 likes | 771 Views
This is a focussed revision guide for use closer to the final exam – a star * next to the slide number indicates a slide you must become an expert about as the exam approaches Ideas how to use the revision cards: - Colour code the cards to show how confident you are with the topic
E N D
This is a focussed revision guide for use closer to the final exam – a star* next to the slide number indicates a slide you must become an expert about as the exam approaches Ideas how to use the revision cards: - Colour code the cards to show how confident you are with the topic - Ask someone at home to test you - Test yourself & highlight key words - Annotate (label) the cards - Re-write your own definitions - ‘Look, cover, check’ - Draw a mind map for some topics - Expand on key words - Explain a topic to someone else - Cut out cards & stick around a room 1
64* What do we know about mountains? Mountain Environments Extreme Environments What a mountain environment is like – physical characteristics: Mountain ranges are considered to be extreme environments due to their height and the difficulties people face living in them. Altitude – mountains are over 610m above sea level – the higher you climb the less oxygen there is – muscles become less efficient and it is difficult to move. Terrain – moving around is difficult due to the steep gradients – steep-sided mountain slopes and valley sides. Weather and climate – weather can change very quickly due to relief rainfall – cumulonimbus clouds gather quickly because warm air is pushed over mountains – the air cools and water vapour condenses forming clouds which soon turn into storm clouds. Storms can last a few hours or a few days. Snow is common – snow and ice at altitude make travelling hard. It is also colder the higher up you are and you can also be exposed to strong winds.
65* What do we know about mountains? Mountain Environments Extreme Environments The Andes – mountain environments have an impact on humans: At 7000km long the Andes run through Peru, Bolivia, Argentina, Columbia, Ecuador and Chile. Economic activity: Aymara Indians – main job is agriculture - they farm potatoes and quinoa (a grain crop) on steep mountain sides. This makes farming difficult so it is all done by hand. Alpaca farming: alpaca fibre and meat are exported to places around the world - although it is not as profitable as it used to be. Tourism: tourists visit many places in Andes including Machu Picchu & for hiking, climbing and fishing holidays in Patagonia. Energy production: Energy is created through a few large scale hydro-electric dams located in Patagonia. This supplies electricity to many of the cities in the Andes. • Low population density of about 1-10 people per sq/km: • very low densities in the high Andes where living conditions are most difficult • highest densities on the Altiplano – a plateau (flat land high up in the Andes) still sparsely populated despite being home to the world’s highest city – La Paz in Bolivia (population 2 million and growing rapidly) • The Altiplano is home to the Aymara Indians – subsistence farmers (grow just enough for themselves) who struggle to scrape a living in the harsh environment.
66 Where are mountains found? Mountain Environments Extreme Environments Mountains are found on most continents – those in red are mentioned in the specification: Alps Andes Appalachians AsirMts Atlas Mts Balkan Mts Caucasus Drakensberg Ethiopian Highlands Great Dividing Range Himalayas Pyrenees Rockies Zagros Mts
67 Where are mountains found? Mountain Environments Extreme Environments • The Andes mountain range is located to the west of South America. They are located between the Nazca and South American plates and run through countries such as Peru, Chile and Ecuador. • The Alps mountain range is located in central Europe. The mountains are in the middle of the Eurasian plate and run through countries such as France, Italy and Austria. • The Himalayas are located in south Asia between the Indian and Eurasian plate. They are the highest mountain range in the world. • The Atlas mountains are located in north west Africa between the African and Eurasian plates. They are located in Morocco and the Sahara desert. • The Great Dividing Range is in east Australia on the Indian tectonic plate. • The Pyrenees are located between Spain and France. • The Rockies are in the west of North America – they are found between the Pacific and North American plates.
68* Where are mountains found? Mountain Environments Extreme Environments • There are different types of plate boundaries: • constructive (divergent) • destructive (subduction) • collision • conservative • Different plate boundaries have different physical processes associated with them: • faulting • folding • volcanic activity • earthquakes The strongest link is between the location of mountains and destructive plate boundaries – pay particular attention to slide 70.
69 Where are mountain environments found? Mountain Environments Extreme Environments A constructive (divergent) plate boundary – e.g. Mid-Atlantic Ridge – middle of the Atlantic Ocean. • plates are moving apart • new crust is constructed as magma (molten rock) from the mantle reaches the surface through the gap between the plates – volcanoes erupt • earthquakes are created by the friction between the mantle and the moving plates • crust on either side of the boundary is often faulted – there are big cracks in it caused by the massive pressures that the moving plates create
70* Where are mountain environments found? Mountain Environments Extreme Environments e.g. The Andes are on the boundary between the Nazca and South American plates. A destructive (subduction) plate boundary Convection currents in the mantle make the 2 plates move together – the heavier oceanic Nazca Plate pushes under the continental South American Plate = SUBDUCTION. In the subduction zone the Nazca plate melts in the mantle creating magma – this rises to the surface where it erupts as lava – volcanoes. The South American plate is also crumpled into fold mountains. Friction between the plates also causes earthquakes.
71 Where are mountain environments found? Mountain Environments Extreme Environments A collision plate boundary - e.g. the Himalayas • two continental plates push into each other • they are the same density (unlike the continental and oceanic plates that meet at a destructive boundary) so neither of them sink into the mantle below • they squeeze upwards forming fold mountains • the massive pressures caused by two plates crashing into each other causes earthquakes • no space for magma to rise from the mantle layer = no volcanoes
72 Where are mountain environments found? Mountain Environments Extreme Environments A conservative plate boundary - e.g. San Andreas Fault on the west coast of North America. • plates move past each other • friction between the plates causes earthquakes • no volcanoes because there is no space for magma to rise from the mantle layer
73 Where are mountain environments found? Mountain Environments Extreme Environments • Key terms – to understand what happens at plate boundaries you need to remember the following: • crust – the solid, outer layer of the Earth – made up of continental and oceanic plates. • mantle – the area of molten (melted), hot rock under the crust – it is made up of a thick liquid called magma (known as lava if it reaches the surface) – hot rock in the mantle rises, and sinks again as it cools – these convection currents cause the plates of the crust to move. • folding and faulting – along with volcanic activity (magma rising to the surface, erupting as lava and solidifying), these lead to the formation of mountains – folding is when the rocks of the Earth’s crust bend; faulting is when they break or crack.
74* Where are mountain environments found? Mountain Environments Extreme Environments Mountains are found in ranges along plate boundaries. Movement of the plates leads to mountain building: Fold mountains – under extreme pressure and heat rock becomes pliable – when two plates meet the layers of rock are slowly crumpled. As a result sedimentary rock formed under the sea can be found above sea level millions of years later in the form of mountains – the rocks fold upwards forming mountains.
75 Where are mountain environments found? Mountain Environments Extreme Environments A fault occurs when pressure at plate boundaries is so great that blocks of rock break apart. This process can occur very rapidly creating earthquakes. The damage caused by this can be very destructive and cause severe changes to the Earth’s surface. Faults rarely occur on their own – they often occur together and are parallel to each other – this can lead to the formation of mountains.
76* Where are mountain environments found? Mountain Environments Extreme Environments Mountains created by faulting - Rift Valley • A rift valley is created when two faults occur parallel to each other and the land sinks between them. The mountains on either side of a rift valley are called block mountains. • Examples include the Great Rift Valley in North Africa and the Black Forest Mountains in Germany.
77* What are mountain climates like? Mountain Environments Extreme Environments 1 The higher the altitude (height above sea level) the colder it gets – about a 0.6c fall in temperature for every 100m you go up. 2 The higher the altitude the thinner the atmosphere is (less oxygen in the air) due to less pressure. 3 Mountains act as a barrier to the wind – weather on the windward side can be quite different from the weather on the leeward side – the west-facing slopes of the Andes are drier and more sheltered than the east-facing slopes. 4 The aspect (direction in which you face) is important – e.g. east facing slopes get sun in the morning but not the afternoon.
78* What are mountain climates like? Mountain Environments Extreme Environments 5 Mountains force air to rise and cool – condensation occurs forming clouds – storms with rain or snow (precipitation) are likely the higher up you are – this is called relief rainfall: The air gets forced up and over the (windward) side of the mountain. As the air rises, it cools, condensation occurs, clouds form and it rains. The air sinks down the other (leeward) side of the mountain – there is little moisture left in the air. The air also warms, evaporation of remaining moisture occurs so no clouds form = no rain. rainfall = 400-800mm a year drier west side in the rain shadow Andes moist, easterly wind Atacama Desert
79 What are mountain landscapes like? Mountain Environments Extreme Environments Glaciers – a glacier is a mass of ice that moves slowly downhill under gravity.
80* What are mountain landscapes like? Mountain Environments Extreme Environments Glaciers erode the landscape using 2 processes: Abrasion – the moving ice uses bits of rock that it carries to wear away at the surface of the rock below. Plucking – as water freezes it attaches to pieces of rock to the ice. When the glacier moves the pieces of rock are pulled with it. The landscape is also affected by freeze-thaw weathering (frost-shattering): During the warm day, melt water sinks into cracks in the rock. At night the water freezes, expands (by 10%) – the process is repeated and eventually breaks off pieces of rock. This rock can be used by the glacier for abrasion.
81 What are mountain landscapes like? Mountain Environments Extreme Environments Freeze-thaw weathering on the mountain side can lead to the formation of scree – a collection of broken rock fragments at the base of the slope. This rock can be used by a glacier for abrasion.
82* What are mountain landscapes like? Mountain Environments Extreme Environments This is a CORRIE (sometimes called a cirque or tarn) – a bowl-shaped hollow with a steep back wall and a shallow lip at the front – a small lake often forms in the corrie bowl. Corries are usually found in the mountains and are formed by ice erosion – when the ice has gone you are left with the landform below: Steep, frost-shattered back wall Corrie lip Corrie lake or tarn
83* What are mountain landscapes like? Mountain Environments Extreme Environments Back wall made steeper by erosion/weathering A corrie forms in stages – A, B, C & D below: Base of hollow deepened by abrasion and plucking Less erosion leaves lip – material deposited on lip Steep, frost-shattered back wall Corrie lake Corrie lip
84* What are mountain landscapes like? Mountain Environments Extreme Environments If 2 corries form side by side a knife-edged ridge is formed between the two steep-sided back walls – this is called an arête Arête
85* What are mountain landscapes like? Mountain Environments Extreme Environments Third corrie – on other side of the mountain If three corries are found together a horn-shaped mountain is formed from the glacial erosion on all sides – this is called a pyramidal peak. Pyramidal peak
86 What are mountain landscapes like? Mountain Environments Extreme Environments Glaciers come in different shapes and sizes – as well as corrie glaciers there are longer valley glaciers which leave glacial troughs when the ice has gone (receded): The valley glacier erodes by abrasion and plucking. Moraine – material transported and deposited by the glacier – can be lateral, medial and terminal.
87 What are mountain landscapes like? Mountain Environments Extreme Environments Glaciers come in different shapes and sizes – after the ice melts we see the effect of the glaciers on the landscape – here erosion by valley glaciers has left behind U-shaped valleys: Ribbon lake – a long, narrow body of water in a deeply eroded glacial valley. Some are trapped behind glacial deposits (terminal moraine). Terminal moraine – where the glacier ended it left behind this pile of stones, boulders and soil, which made a ridge across the valley.
88 What are mountain landscapes like? Mountain Environments Extreme Environments Glaciers come in different shapes and sizes – after the ice melts we see the effect of the glaciers on the landscape – here erosion by valley glaciers has left behind U-shaped valleys: Glacial trough/U-shaped valley – a deep, steep-sided, flat-bottomed valley – usually very straight. Truncated spur – before glaciation this was a ridge round which a river valley curved. Glaciation eroded away the end of the ridge leaving an area of high ground protruding into the valley.. Hanging valley – was a small tributary valley to the main river valley before glaciation – the main river valley eroded deeper during glaciation , leaving this smaller valley above the level of the main valley– can be a waterfall between the hanging valley and the main valley.
89 What are mountain landscapes like? Mountain Environments Extreme Environments Rivers also erode the landscape in mountain environments – these are known as fluvial processes – they create certain landforms: V-shaped valleys • A V-shaped valley – the process begins with the river eroding downwards (vertically) due to: • abrasion – sand and stones wear away the bed and banks of the river channel • hydraulic action - the fast-flowing water is forced into cracks in the banks breaking them up • solution – water dissolves soluble minerals from the bed and banks
90 What are mountain landscapes like? Mountain Environments Extreme Environments Rivers also erode the landscape in mountain environments – these are known as fluvial processes – they create certain landforms: V-shaped valleys 1) The river erodes downwards as boulders, stones and rock particles are bounced and scraped along the channel bed. 2) As the river cuts down, the steep sides are attached by weathering. This breaks up and loosens the soil and rock. 3) The loosened material slowly creeps down the slope because of gravity or is washed into the river by rainwater. 4) The river carries material away and the end result is a V-shaped valley.
91 What are mountain landscapes like? Mountain Environments Extreme Environments Rivers also erode the landscape in mountain environments – these are known as fluvial processes – they create certain landforms: Interlocking spurs The photograph shows how hills stick out like the teeth of a zip in the river’s path – these are called spurs. The river doesn’t have the energy to erode the spurs, so it winds its way around them – this creates the landform of interlocking spurs. IF THE V-SHAPED VALLEY IS FILLED WITH ICE (A VALLEY GLACIER), IT WILL ERODE THE LANDSCAPE CREATING A U-SHAPED VALLEY. THE INTERLOCKING SPURS WILL BE WORN AWAY BY THE ICE LEAVING TRUNCATED SPURS.
92 What are mountain landscapes like? Mountain Environments Extreme Environments Rivers also transport and deposit material – these are also fluvial processes – they create certain landforms: Flood plains • If a river flows on the floor of a U-shaped valley it can flood the land on either side of the river channel – this is the flood plain. • When the river floods the material it has carried (transported) is deposited in the form of fine silt called alluvium – this builds up the flood plain and makes the land very fertile for crops. flood plain alluvium
93 How do people use mountain environments? Mountain Environments Extreme Environments • Tourism – Machu Picchu – an example of a cultural/sight-seeing holiday • The mysterious lost city of the Incas, high in the Andes – 70 km from the nearest city – Cuzco. • Half a million people visit every year putting pressure on the site and the surrounding environment – 2000 a day (grows by 6% a year). • Tourists get there by train (from AguasCalientes) or by hiking along the Inca Trail (6000 in 1984; 82000 in 2004). • AguasCalientes can only be reached by train – there are plans to build a road (the town’s population has already grown from 500 to 4000 in 10 years). • Plans to build a cable car to the site from AguasCalientes. • IMPROVEMENTS TO ACCESSIBILITY WOULD INCREASE THE VISITOR NUMBERS EVEN MORE.
94* How do people use mountain environments? Mountain Environments Extreme Environments • Tourism in an LEDC – Machu Picchu – an example of a cultural/sight-seeing holiday • There are social/economic (s) and environmental (e) costs and benefits to tourism: • Tourism – costs – negative impacts • site is being eroded by tourists feet (e) • Inca trail – vegetation worn away by walking and timber cut for fuel (e) • tourism is an unreliable employer – unemployment in the low season & poorly paid jobs (s) • more sewage in AguasCalientes pumped into river & increased litter (e) • money from tourism goes to other countries where the travel companies are based (s) • loss of traditional culture - people forced off their land to make way for construction to aid tourism (s) • poor working conditions (e.g. for porters) (s)
95* How do people use mountain environments? Mountain Environments Extreme Environments • Tourism – Machu Picchu – an example of a cultural/sight-seeing holiday– benefits/positive impacts • creates jobs – formal (e.g. in a hotel/travel guides) & informal (not employed by anyone – street vendors selling postcards) (s) • entrance fees and taxes on tourism = extra money for the Government of Peru (s) • new facilities for tourists benefit local people (e.g. new infrastructure – roads/bridges – new bridge across the Vilcanota river to Machu Picchu will bring more tourists and can also be used by farmers to get goods to market quicker than before improving the quality of their life) (s) • THERE ISN’T A SINGLE ENVIRONMENTAL BENEFIT
96 What are the alternative futures for the Andes? Mountain Environments Extreme Environments There are positive impacts of tourism at Machu Picchu, but tourism at the site is currently unsustainable:
97 What are the alternative futures for the Andes? Mountain Environments Extreme Environments • Tourism – Machu Picchu – an example of a cultural/sight-seeing holiday– solutions: • Sustainable, eco-tourism – responsible travel to natural areas which conserves the environment and sustains the well-being of the people: • offer fair wages • buying fresh local produce • minimising waste, leaving no litter • ensuring good working conditions (e.g. for porters) • trekking groups limited to 12
98* What are the alternative futures for the Andes? Mountain Environments Extreme Environments Tourism – Machu Picchu – an example of a sustainably managed holiday - eco-tourism : HIGH INCA TRAIL TREK TO MACHU PICCHU
99* How do people use mountain environments? Mountain Environments Extreme Environments Indigenous people The Aymara Indians live on the Altiplano – a sparsely populated plateau formed from deposits brought down from the mountains by wind and water – they make poor soils & most Aymara Indians are subsistence farmers (growing enough food to survive) – struggling to make a living in a harsh environment. The terrain makes it difficult to take food to markets to sell. The Indians depend on two crops – potatoes and quinoa. Quinoa is a grain crop with all the nutritional benefits needed for a healthy diet (seeds are cooked like rice & leaves are boiled like spinach) – the stalks can also be burnt for fuel. Quinoa grows well at high altitudes in poor soil with little rainfall, in both hot and cold weather. The Aymara also keep llamas and alpacas for meat and wool.
100* What are the alternative futures for the Andes? Mountain Environments Extreme Environments • The future of farming in the Andes – sustainable or not? • Alpaca farming – large-scale ranching: • Countries such as China and Australia now have their own alpaca herds – to protect the future of the industry in Peru large-scale ranching is being developed with wealthier farmers taking over smaller farms – many see this as more sustainable: • farmers invest large amounts in pure alpacas with finer fibres that make more money • farmers have buildings insulated against the cold by mud – alpacas can be moved indoors when it snows – alpacas survive the winter months • fibres go to a processing factory in Arequipa – textiles are manufactured for export – using machinery to produce clothing for China, USA, Australia and New Zealand large profits can be made.
101 How do people use mountain environments? Mountain Environments Extreme Environments Indigenous people – rural to urban migration For years people from the Altiplano have been migrating from the countryside to the city – rural to urban migration: Push factors cold, dry climate; poor soils; few jobs other than farming; poor educational opportunities; lack of healthcare; poor diet and malnutrition (the renewed popularity of quinoa is helping with this), lack of clean water and electricity Pull factors more work; higher income (30 times higher than farming); educational opportunities; housing; healthcare and a higher life expectancy.
102* What are the alternative futures for the Andes? Mountain Environments Extreme Environments • The future of farming in the Andes – sustainable or not? • Quinoa farming: • quinoa is one of the planet’s most nutritious foods – a health food for people in Europe, USA, China and Japan • farmers can now sell their quinoa crop – prices have tripled since 2006 – the crop has improved quality of life of people in some of the poorest regions of the Andes • However, quinoa is worth more to the indigenous people as something to sell – as a result they eat less of it themselves and their diets have become much poorer as a result. People are returning home from towns and cities to grow quinoa, but bitter disputes are breaking out about who owns the land on which quinoa is grown. • Ethical consumers in MEDCs are not always aware that quinoa is now no longer affordable to indigenous people in the Andes – it is better for indigenous people to sell the crop and their traditional diet is suffering as a result.
103 How do people use mountain environments? Mountain Environments Extreme Environments • Other uses of the Andes by people: • Scientists use the Andes: • to develop commercial farming methods – e.g. world renowned animal experts are researching alpacas to make sure that the purest animals with the finest wool can reproduce and maintain the quality of the fibres in future generations • to understand volcanic activity and develop the potential of geothermal power • to understand the impacts of climate change through studying glacial retreat – understanding the impacts on water supply in the Andes
104 How do people use mountain environments? Mountain Environments Extreme Environments Mountains have a key role in the hydrological cycle – precipitation (rain, hail, sleet or snow) levels are high in mountain areas due to relief rainfall – a mixture of surface runoff (rainwater running along the ground), throughflow (rainwater flowing downhill through soil) and groundwater flow (slow movement of water downhill through rock beneath the ground) supplies water to major rivers. condensation precipitation rivers carry water back to the ocean evaporation
105* How do people use mountain environments? Mountain Environments Extreme Environments • Mountains can provide valuable natural resources that can be exploited – the Andes are a source of hydro-electric and geothermal power: • Hydro-electric power (HEP): • Running water is used to drive turbines. Certain physical conditions are needed – these conditions are very common in the Andes with its deep valleys and rivers: • fast flowing water – the Andes have very steep gradients increasing water speed – excellent for HEP • high rainfall all year & snow melt • either a lake as a natural water store, or a narrow and deep valley with rocky sides to build a dam and create a reservoir • Once the HEP is operating, there are many advantages making HEP a sustainable form of energy: • continuous production - renewable energy • no water or air pollution – no CO2 created • low cost • water can be used for other purposes when it reaches further downstream • Unfortunately, sites with good physical conditions are not found anywhere. If a dam needs to be built to store enough water, this increases costs. Flooding the land behind the dam, drowns forests, destroys wildlife habitats and forces people off their land.
106 How do people use mountain environments? Mountain Environments Extreme Environments Mountains can provide valuable natural resources that can be exploited – the Andes are a source of hydro-electric and geothermal power: Hydro-electric power (HEP): Case study in the Andes – Peru gets 80% of its electricity from HEP. The Yuncan Dam Project is located on the Puacartambo and Huachon rivers in north east Peru. It cost $262m to build. It produces 901GWh of electrical power per year with most of this electricity going to the national grid in Peru. However, because hydro-electric power varies with rainfall amounts and snow melt, in the last few years Peru has been reducing its dependence on HEP but using more and more natural gas. As glaciers in the Andes melt due to climate change, Peru has lost water equivalent to 10 years supply to the capital city Lima.
107 What are the alternative futures for the Andes? Mountain Environments Extreme Environments Mountains can provide valuable natural resources that can be exploited – the Andes are a source of hydro-electric and geothermal power: Hydro-electric power (HEP): There are many remote villages in the Andes with no electricity supply. People are leaving such villages to find work in nearby towns and cities – rural to urban migration. HEP has been used on a small scale to provide electricity to isolated communities – with pipelines and small turbines generating electricity 24 hours a day, villages have been regenerated with new businesses growing – less people are now migrating away. small-scale, sustainable use of HEP
108* What are the alternative futures for the Andes? Mountain Environments Extreme Environments Mountains can provide valuable natural resources that can be exploited – the Andes are a source of hydro-electric and geothermal power: Geothermal Power – another renewable form of energy that generates electricity without burning fossil fuels and creating CO2: The Andes also contain many volcanic areas - the volcanic rocks may heat water so that it rises to the surface naturally as hot water and steam. Here the steam can be used to drive turbines and generate electricity. Unlike HEP, geothermal is not dependant on the weather but installation and start up costs can be expensive and drilling down can sometime release harmful gases. Currently the Andes has few geothermal power stations but plans are underway for this type of energy to become more and more exploited.
109* What challenges do mountain environments pose and how can they be overcome? Mountain environments Extreme Environments Mountaineers use the Andes because they offer the opportunity for great achievements, climbing spectacular and challenging mountains (e.g. Siula Grande at 6,344m). Mountaineers face frostbite, injury and even death – less oxygen at high altitudes – muscles become less efficient – must gain height slowly – 600m a day. Whilst there is plenty of snow and ice, water is in short supply as is food. Other challenges for people include: Transport and accessibility – very difficult due to steep slopes – roads and railways have to be constructed around these – costly and difficult to build – often walking is the only option. Snow line in Peru is at 4500m – snow and ice make travelling even harder. Storms can last days during which travel is impossible. Remoteness – because transport is so difficult people living in remote areas have little or no contact with the world outside their village. Many places are a long way from specialist help – Aconcagua is 113km from the nearest city – if an emergency happens often the only way out is by foot. Shelter – in a storm shelter is needed quickly – local residents can use their houses, but mountaineers will have to put up tent, dig a snow hole or find a place in the rocks. Indigenous people – develop larger lungs and produce more blood cells to deal with lower air pressure and lack of oxygen. They have adapted to survive – e.g. growing crops on steep sided valleys – can only produce small amounts. It is however difficult to access education to get the skills needed for better jobs and many live without a clean water supply and sewage disposal because the cost of providing this for remote areas is too high and natural water is in short supply – dehydration is a problem at high altitudes.
110 What challenges do mountain environments pose and how can they be overcome? Mountain Environments Extreme Environments Mountaineers manage the challenges in different ways: Multi-layered clothing – trap air – insulation from the cold Reflective glasses – protects eyes from the glare Equipment – lightweight oxygen cylinder, ice axe to climb steep ice & altitude stoves to melt ice for water supply Insulated gloves – protection from frost bite Windproof jacket – duvet jackets filled with feathers – warm and light – keep body’s core temperature stable by avoiding cold Spiked boots – avoid slipping and falling in difficult terrain – snow and ice.
111* What challenges do mountain environments pose? Mountain Environments Extreme Environments Natural hazards – the 10 highest volcanoes in the world are found in the Andes – earthquakes are also frequent: Earthquakes– 16th August 2007 – earthquake measuring 7.9 on the Richter scale hit Peru - 337 confirmed deaths. Volcano – Ubinas – Peru – spewed acid-laden ash over surrounding area – 640 families in 6 villages affected – eye and breathing problems. Animals died from drinking contaminated water & eating contaminated grass – these animals had been a source of food and money – poverty made worse.
112* What challenges do mountain environments pose? Mountain Environments Extreme Environments • Natural hazards – • Landslides/landslips – 1998 – city of Santa Teresa destroyed – 15 people died – 2000 residents lost homes and livelihoods. Bridge over the Vilcanota river connecting the city to Machu Picchu was destroyed – now a 15 hour journey to Cuzco in order to transport goods • Avalanches – large amount of snow falling suddenly down a mountainside – caused by: • snowfall – usually within 24 hours of heavy snow (over 30cm) • temperature – increases weaken upper layers of snow • wind – uneven snow on leeward side dropped by wind • ground cover – most avalanches caused by smooth ground • slope – most on convex slopes between 30 and 45 degrees (where most ski slopes are found)