geography paper one

what is hydraulic power

hydraulic action is where the force of waves hits against a cliff face and causes rock to break off

what is abrasion

where pieces of material are picked up by waves and hit or scrape against sea bed or the side of a cliff. it acts like sandpaper

what is attrition

where different bits of material hit each other, causes them to break apart and become smaller and more rounded.

what is a wave cut platform

over time cliffs are eroded by destructive waves creating a wave cut platform. it is the process where the cliff retreats

what are the factors that affect hazard risk

population, urbanisation, climate change, development levels.

what is the distribution of tectonic hazards like

most tectonic activity( 95% of earthquakes) occurs in the bands along plate margins

The Pacific Ring of Fire; horseshoe shaped zone circling Pacific Ocean it is home to 90% of global earthquakes and 75% of active volcanoes.

Examples: destructive plate margin like the Nazca plate subducting under South American plate (Chile)

Nepal earthquake 2015

• 7.8 on richter scale

• Australian plate colliding with the Eurasian plate

• 9000 deaths

• 22000 injured

• 3 million made homeless

• avalanches on Mount Everest killed 19 people

• they had to rely heavily on foreign aid (UK, India ,China)

• the damage cost $5 billion which was less than in chile but it was 49% of Nepals GDP

Chile earthquake 2010

• 8.8 on richter scale (magnitude)

• nazca o plate subducted under South American plate

• 500 death

• 12000 injuries

• 220000 houses destroyed

• damage to Santiago airport

• $30 billion(15 percent of national wealth)

• chemical plant fire near Santiago

• landslides cutting off remote communities (1500km roads)

Chile responses

• temporary repairs the main highways were completed within 24 hours

• power water restored to 90 percent in 10 days

• didn’t have to rely that much on foreign aid because of strong economy

• full recovery took 4 years

Nepal responses

• heavily relied on foreign aid 6.7 billion international aid eg India uk china

• helicopters search rescue teems rescued trapped people

• still hasn’t fully recovered after eleven years and still restoring historic temples

why live in a area vulnerable to natural hazards?

1. farming; volcanic ash is very rich in nutrients so create exeptionally fertile soil.

2. Mining: tectonic activity brings valuable minerals closer to surface creating mining jobs

3. Tourist industry

4. Geothermal energy provides cheap renewable source of electricity and heating

5. Trust in the modern monitoring systems

Typhoon Haiyan

• Philippines LIC

• 6300 deaths from storm surges

• 90 percent city of tacloban destroyed

• 1.1 million houses destroyed

• 600000 hectares of farmland wiped out

• 30000 boats destroyed

• 6 milion madę homeless

• outbreak of disease eg cholera due to contaminated water

• looting violence broke out in tacloban because of food shortages

• oil tanker leaked 800 000 litres contaminating fishing water and mangroves

Typhoon Haiyan responses

• the government evacuated 800 000 people

• foreign aid uk us gave $1.5 billion

• 1200 evacuation centres and hospitals established within days

• improved coastal defences

• planting mangrove forests to act as natural barriers

• cash for work schemes to clear debris

what is prevailing wind

direction in which the wind blows most frequently

what is the eye of a hurricane like

the centre of a tropical storm has clear conditions created by air converging at the centre and then sinking

what is the eye wall

a thick band of cloud around the eye with high wind speeds and heavy rain

what is the Hadley cell

circulation cell nearest to equator responsible for storms at equator

Ferrell cell

circlulation cell bringing warm air north

what is the polar cell

circulation furthest from equator that brings cold air south

what is a greenhouse gas

a gas that absorbs and remits infrared radiation warming the earths surface

what is a honey pot site

place of special interest attracting tourists

what is an agribusiness

large scale commercial farming and food supply

what is the canopy layer

tall trees that block out area beneath because the trees in tropical rainforests are so densely arranged

what is a bar

a ridge of sand or shingle across the entrance of a bay or river mouth created by spit over time and longshore drift. It creates a lagoon.

what is a spit

ridge of sand or shingle deposited by the sea creating a ledge into the water.

what is a consumer

a creature that eats herbivores and or plant matter

what is subsistence farming

type of agriculture producing food and materials for the benefit of the farmer and his family

what is over cultivation

exhausting soil by over cropping land

what is beach nourishment

addition of new material to a beach artificial by dumping large amounts of sand or shingle

what is beach reprofiling

changing profile or shape of beach direct transfer of material.

what is chemical weathering

decomposition of rock caused by chemical changes in its mineral composition typically done by rainwater reacting with minerals.

what is dune regeneration

building up dunes and increasing vegetation to strengthen them and prevent costal retreat

what is a discordant coastline

bands of hard and soft rock are perpendicular to the coastline eg swanage bay d

what is slumping

rapid mass movement which involves a whole segment of the cliff moving down slope along a saturated plane or line of weakness

what are embankments

raised banks constructed along rivers they make the river deeper so it can hold more water

Somerset levels

flood 2014

• it was the wettest January since 1910 and rain had saturated the ground increasing surface runoff

• the Somerset levels have rivers tone and parrot that had not been dredged for 20 years significantly reducing capacity.

impacts

• 600 plus houses flooded

• 16farms evacuated

• villages like Muchelney cut off for weeks

• 14000 hectare of agricultural land submerged

• floodwater contaminated with sewage oil and chemicals stagnant water had to be reoxygenated to protect marine life

Management and responses

• flood action plan £20 million plan launched to dredge 8km of rivers tone and parrett

• raising road levels