Supervolcano- Yellowstone, Montana, USA
- The caldera is bulging up beneath Lake Yellowstone, up to 70cm in some places
- The Yellowstone magma chamber is 80km long, 40km wide and 8km deep
- An eruption today is likely to destroy 10 000km2 of land, kill 87 000 people, 15cm of ash would cover buildings within 1 000 km and 1 in 3 people affected would die. Also, global climates would change, crops would fail and many people die as a result
Measuring Earthquakes- The Richter Scale
- A logarithmic scale, from 1- no upper limit, based on scientific recordings
- Expressed using numbers, measured with a seismometer, gives no indication of damage caused
Measuring Earthquakes- The Mercalli Scale
- An arithmetic scale, from 1-12
- Expressed using roman numerals, measured by observations, is based on opinions only
Earthquake in a MEDC- Kobe, Japan
- 5:46AM 17th January 1995
- 7.2 on the Richter scale, over 6 000 killed and over 40 000 seriously injured
- EFFECTS: City’s infrastructure ruined: gas mains ruptured, water pipes fractured, 2 million homes without electricity, fires in the city, more than $220 billion damage
- RESPONSES: Friends and neighbours searched the rubble for survivors, Motorola maintained telephone connections free of charge, transport networks slowly reopened, new buildings built further apart, with flexible steel frames
Earthquake in a LEDC- Sichuan, China
- 2:28PM 12th May 2008
- 7.9 on the Richter scale, over 69 000 killed and over 374 000 seriously injured
- EFFECTS: 80% of the buildings destroyed, at least 5 million homeless, communications brought to a halt, roads blocked by landslides, $75 million in damage
- RESPONSES: Helicopters assigned, army troops moved the rubble and searched for survivors, donations made from the Red Cross for running the temporary camps, one million temporary small homes built
Tsunamis- Indonesia
- 26th December 2004 involving India, Thailand, Malaysia, Indonesia, Sri Lanka, the Maldives
- Triggered by an earthquake out to sea which was 9.3 on the Richter scale and it occurred at the plate boundary between the Eurasian and Indo-Australian plates. The plate movement caused a column of water to be displaced which grew in height and proximity as it travelled
- EFFECTS: Around 220 000 killed and 650 000 seriously injured and up to 2 million homeless, up to 25m tall waves, buildings wiped out in seconds, flooding in Sri Lanka, Maldives swamped, buildings damaged from earthquake itself in Indonesia
- RESPONSES: Mass burials of the dead in mass graves, aid workers distributed water purification tablets, food, sheeting and tents, £100 million in donations from the UK, medics and scientists arrived, £40 million spent on rebuilding projects in Sri Lanka and Indonesia, Indian Ocean Tsunami Warning System set up in June 2006 to prepare for similar disasters in the future
Water on the Land…
Processes and Landforms of Rivers- River Tees
- In North East England, source at Cross Fell in the Pennines 600m asl. Tees is 100km in length, lots of surface run off near source due to steep V shaped valley sides and impermeable rock
- UPPER COURSE: Interlocking spurs create steep banks in the upper course of the river. Sediment is full of large, sharp stones. River looks murky because of suspension and the peat staining it brown. White water here too used for white water rafting. Cow-green reservoir is man made so industries and people on the lower land have water. Water can be released into river if there’s a significantly reduced flow. Most powerful section of the river. 350m asl, valley flattens out and land used for cattle and sheep. End of upper course: High Force Waterfall, plunge pool at base, hard igneous rock above soft rock is called Whinstone, public footpath around waterfall called the Pennine Way and High Force Hotel. A gorge has formed downstream of the waterfall, which attracts tourism
- MIDDLE COURSE: 95% of the land used for farming. Lots of the river’s energy is lost to friction here, valley flattens and 10km floodplain created, also arable farming because of the soil’s fertility, settlements start to be built, meanders start
- LOWER COURSE: Darlington 30km from sea, but 75km by river because of meanders. Yarm 18km from mouth, too far for big ships to reach there. Stockton used for major industry, bridge built there during the Industrial Revolution, blocking of access to Yarm. Land predominantly used for industry, but some for recreation and tourism. Bed load very fine. Used to be marshland there, but now power station, chemical works, oil refineries, iron & steel works and a railway station because cheap and flat land, good transport links and not many building (undesirable place to live). Tunnel built in case of drought to Kielder Reservoir. Deep river suitable for ships. Seal Sands nature reserve at the mouth. Land use determined by geographical features of river
Flooding in a MEDC- Boscastle, Cornwall
- 15th August 2004, North Cornwall, UK. 2 inches of rain (one month’s worth) in 2 hours. 6 emergency helicopters. Tintagel and Camelford used for shelter
- Rivers Jordan and Valency were responsible, they converge at Boscastle, 100 cars lost to sea
- Flooding in a LEDC- Bangladesh
- 1998- 70% of country less than 1m below sea level, flooding ensures very fertile soil here
- CAUSES: Human- Deforestation in Nepal and Tibet (root soak up water, so more surface run off), building of dams in India, urbanisation, flood defences Physical- low lying country, snow melt, cyclones etc., rivers, lakes, swamps on 10% of the land
- EFFECTS: Over half the land was flooded, over 1000 killed, over 1 million homeless, diseases (e.g. diarrhoea) spread, $1 billion damage, shortage of drinking water
- RESPONSES: 400 tonnes of rice from government, boats, medicines, water, plastic sheeting from aid agencies (later on replanting of trees and new houses constructed, seven huge dams to be built)
Hard Engineering Strategies- Mississippi, USA
- Primarily in response to the August 1993 floods. Its 200km wide flood plain makes it a high flood risk river
- Dams and reservoirs: six dams on the Missouri River create reservoirs which help to prevent flooding and provide water supply and hydro-electricity
- Diversionary spillways: overflow channels that take surplus water in times of flood e.g. the diversionary spillway into the Gulf of Mexico, which reduces flood risk at Baton Rouge and New Orleans
- Cutting off meanders (channelization): makes the course straighter and shorter, so get rid of water quickly. This shortens the length of the river by cutting through the meander necks and thus increasing the speed of the river
- Strengthening levees: concrete mattresses prevent erosion of levees
- Soft Engineering Strategies- The River Quaggy, UK
SE London.
- Previous hard engineering methods increased flood risk, so they built a new channel for the river above ground through Sutcliffe Park and created a multi-functional open space (a washland). Reduced risk of flooding for 600 homes and businesses in the area, diverse environment for wildlife
Managing Rivers- Kielder Water, UK
- Kielder reservoir, NE England, is one of the largest artificially created lakes in Europe, it regulates the river Tyne and was constructed due to rise in water demand between 1975 and 1982
- An aqueduct transfers water to the Wear and Tees rivers so has enormous flexibility
- Was chosen for poor farming land and few people, narrow valley allows for shorter, cheaper dam, water catchment area collects the maximum volume of water possible, Whinsill underlying rock provides good base for dam, regular and heavy rainfall keeps dam filled up
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ADVANTAGES: Creates water source for many settlements, picnic sites for walkers, study centre for geographers, footpaths created, caravan sites (and therefore tourism), water-sports and nature reserves
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DISADVANTAGES: People living in areas of deficit wanted a reliable water source quickly, but this took time (as the reservoir had to fill up)
Ice on the Land
Retreating Glaciers- South Cascade Glacier, USA
- Washington State, USA. Part of a group of three glaciers monitored by a geological group for the past 40 years
- All three glaciers show signs of retreat from data of stream run-off, air temperature and mass balance (glacier budget). Could be a result of global warming
Tourism in Glacial Areas- Chamonix, France
- Chamonix is in a naturally beautiful area which attracts tourists all year round for both winter and summer activities
- WINTER: Tourists can ski, snowboard, ice climb, paraglide, show shoe, dine in local restaurants, swim, shop and see the sights. There are 60 000 visitors a day to Chamonix in the winter
- SUMMER: Tourists can hike, mountain bike, visit the Mer de Glace glacier, rock climb, paraglide, do rafting, canyoning, pony trekking, summer luging and go to music concerts. There are 100 000 visitors a day to Chamonix in the summer
- CONFLICTS: Different abilities of skiers (e.g. on nursery slopes), language barriers hinder communication, mountain bikers competing for the same space as hikers on potentially narrow and uneven tracks, music causing noise pollution, scaring birds away and ruining the experience for birdwatchers, ignorant winter sports enthusiasts going off-piste and having to be rescued by mountain rescue team, costing them time and money, lack of parking in village, increased traffic due to tourism, crowding, expensive goods in the shops and restaurants, making essential products for locals that remain unnecessarily expensive, high cost of houses, hikers etc. erode the footpaths, litter, exhaust gases, noise and light pollution in the town
- MANAGEMENT TECHNIQUES: Chamonix authority ensures clean energy buses in conjunction with free local transport. The Espace Mont-Blanc initiative involves France, Italy and Switzerland in matters relating to conservation, forests, water resources and international transport. Tomorrow’s Valley scheme promotes sustainable management (e.g. renovating historic buildings)
Avalanches- The European Alps
- On average, there are over 100 million visitor to the Alps each year, with 150 people being killed in avalanches
- The winter of 2005-06 saw 49 people being killed in off-piste avalanches alone. Fluctuating temperatures, irregular weather patterns (including snow and rainfall) led to a greater number of avalanches than usual. Many people ski off-piste when in search of fresh snow, which may not have yet stabilised
- In January 1994, six British doctors went skiing but after an avalanche, there was only one survivor
- The importance of mountain safety is being highlighted by The Ski Club of Great Britain who are running courses in safety
The Impact of Tourism on Fragile Environments- Antarctica
- Small scale tourism began there during the 1950s
- The Marco Polo cruise ship provides a 23 day cruise around the coast of Antarctica.
- More than 99% of Antarctica is covered in ice, so little is left for tourist activity.
- Few tourists are allowed on the ice, but they can do walking, kayaking, skiing, climbing, scuba diving and helicopter flights
The Impact of Tourism on Fragile Environments- Abondance, France
- In 2007, following 15 years of unreliable snowfall, the ski lifts in Abondance closed for the last time. The local council is either considering developing other forms of winter sports (e.g. snowshoeing etc.) to reduce its dependence on deep snow for traditional skiing or to develop its summer programme of activities (e.g. hiking etc.) to promote the town as an all-year round resort rather than just a winter one. It is difficult to maintain a balance between protecting the environment or ensuring a secure economic future for the region