geography case studies

• Regular floods in late summer. Monsoon climate 80% rain in four months.
• 90% land is less than 10m above sea level.
• Brahmaputra river discharge increased by melting snow and ice from Himalayas.

Physical factors

• Monsoon came suddenly after very dry and early summer.
• heavy rainfall Assam record 169.5mm in 24 hours on 22nd July (900mm in total for july)
• ground completely saturated due to long heavy rainfall,  increased surface runoff and discharge
• peak discharges for Ganges, Brahmaputra coincided increaseing discharge downstream.

Human factors.

• Deforestation in Nepal and Himalayas meant less interception and increased discharge.
• growth of urban areas due to migration increased amount of surface runoff.
• Collapse of old earth dams in Madhya Pradesh, India caused further flooding.

Social impacts

• Over 2000 people died.
• Wells became polluted with sewage, over 100,000 poeple caught water-borne diseases e.g dysentery/diarrhoea.
•  Estimated 25 million made homeless.
• Dhaka inundated especially poorer districts and shanty towns near river.
• 4000 schools affected and 44 destroyed.

Economic factors

• Estimated $1 billion due to damge to crops and property.
• Factories closde around Dhaka, poorest became unemployed.
• Widespread loss of livestock e.g 80% of country rely on agriculture.
• world price of Basmati rice rose by 10%, 550,000 hecters couldn't be planted at peak time.
• 10,000km of roads destroyed. landslides blocked roads in Nepal and Assam highlands.
• Increased debt. Farmers for food/seeds. governments imported food and medicine.

River Eden runs through North Cumbria reaching sea near Carlisle.

• Large Drainage basin, large volume of rainfall leads to high river discharge.
• Parts of basin have Steep sides water runs quickly into river.
• Many streams drain quickly into basin making a short lag time.

Physical factors

• Heavy rainfall on 6th January for 36 hours. 200mm of rainfall recored equv of four months.
• Rain fell on saturated ground water didn't soak into ground, went straight into river.
• Very high peak discharge (over 1520 cumecs) compared to average 52 cumecs.

Human factors

• Carlisle large built-up area, impermiable concrete and tarmac surfaces, little soil/vegetation. causing little infiltration and high surface runoff.
• Drains and sewage systems overflowed becoming source of flooding. 25% of flooding problems were associated with overflowing drains.

Social impacts

• Three people died.
• Over 3000 people made homeless and thousands of personal possessions damaged.
• Children lost education, four schools severly flooded.
• Increase in stress-related illnesses.

Economic impacts

• took a year to repair damage to homes, costing over £100 million.
• 350 businesses had to shut down, no electricity, telephone service or transport.
• United Biscuits largest employer flooded 3m of water £5 million damage. 33/1000 lost jobs.
• 70 000 addresses had no power, sewage works and police station severely flooded.
• 80 buses most of public fleet destroyed. Roads and bridges damaged Warwick Road.

Environmental impacts

• Floods increased river bank erosion, rivers polluted with rubish and sewage.

• asthetic scenery attracts tourism.
• Antarctica Treaty System. 50 members developed in 1961.
• Number of tourists risen from 6700 in 1992 to 46,000 in 2008.

Damage to ecosystems

• Fishing disrupts food chains. Krill fishing in Southern Ocean deplete food for whales and penguins. overfishing of Patagonian Toothfish in Antarctica.
• Large cruise ships increase pollution. development of roads and hotels disrupts widelife.

Arctic tundra is found in Greenland, Northern Russia and Canada.

• Minerals e.g gold in Canada  and Alaska lead to development in tundra areas.
• Oil exploitation in Alaska over last century.

Damage to ecosystems.

• Bottom trawling disrupts ecosystems, increases turbidity reducing light levels. Gulf of Alaska, Greenland Sea  and the Barents Sea.
• Oil spills occur during transport. 189 huge spill of coast of Alaskam Exxib Valdez oil tanker crashed, 40 million liters of oil spillt, killing 250,000 birds and fish.
• Pipelines Leak causing oil spils, 1977-94 average 30-40 spills a year from Trans-Alaska pipeline, some by intentional attacts or forest fires.
• Mining creates ground/surface water contamination. Lead-zinc mine in Maarmorilik (Greenland) closed 1990 lead and zinc still released pollution near fjords.

Sustainability.

• National parks, Denali National Park Alaska 1917, cars Banned fishing quotas inBarents Sea. oil pipes have automatic shut-off balves minimise oil spills.

Inuit people live in Northern canada, Greenland and Russia.

• Native tribes lived in tundra climate for thousands of years.
• Newcomers from Europe and US interest in tundra since 17th century opportunites for whale and seal hunting. whales for Oil which is used to fuel lamps and make candels.
• Newcomes had negative effect on natives, brought new diseases
• Late 19th century 90% of Inuvialuit (Canadian tribe) killed by tuberculosis,measles and flu.
• Increase of whaling,selaing and fishing reduced numbers of animals available for Inuit people

Lifestyle change required

• Not enough resources for Inuit tribe to support themselves by hunting and fishing, must find paid employment.
• Young Inuits don't learn traditional skills.
• Few jobs available go to more educated white population.
• Unempoloyment nearly 50% amongst Inuit communities, have to rely on government help.
• Change in employment led to Inuits living in Permanent settlements rather than nomadic.

Stage 1 (prehistoric to about 1760) and tribes in Brazilian rainforest.

• Total population small 6 million in 1700
  Poor diet and hygiene, wars and diseases such as black Death, caused high DR 

Stage 2 (1760-1880) and Nepal/Afghanistan.

• Populaton grows quickly, 5 times bigger by 1880's (30 million). improvments in farming and medicine reduce starvation and disease so DR falls Birth rate remains high economy grows.

Stage 3 (1880 - 1940) and Egypt.

• Population continues to grow but slower, 41 million by 1941. Birth control improved  BR falls. Death rate continued to fall except WW1. food supply, medicine, hygine all improve.

Stage 4 (1940-today) and most of Europe and USA.

• Growth slowed down, 56 million by 1981. DR low except during WW2, BR low except baby booms after WW" and 60s.