Case Studies Flashcards
Name an example of a flood in California
Sacramento
December 2006-January 2007
4,000 displaced, $245 million in damages
Why do floods occur in California?
Due to mountain and plain topography around sacramento
Coincide with El Nino
Name an example of a wildfire in California
2007 in South California
22 killed
1,300 homes destroyed
What plate boundary is California on?
Conservative plate boundary
North American plate and Pacific plate are both sliding past each other but at different speeds (N.American is faster) causing friction
Why do droughts occur in California?
Wind blown from Arizona desert which is dry with no moisture
La Nina years
What is the San Andreas Fault and where does it run along?
Fracture between the two plactes
Along the California coast from Los Angeles to San Francisco
Why do earthquakes occur in California?
Friction is eventually overcome and the plates slip past in a sudden movement. The shockwaves created produce an earthquake
Name an example of an earthquake in California
San Francisco 1989
60 killed
Why do landslides occur in California?
Coastal erosion
Steep land
Extreme weather
Earthquakes
Why is California vulnerable?
Population density of LA: 3000km2
20% live below poverty line in LA
Why do tsunamis occur in California?
Undersea
Seismic sea waves created from movements on the fault
On the north coast, the plates turn around and create a destructive plate margin (Cascadia subduction zone)
Name an example of a tsunami in California
Alaska 1964
Earthquake generate tsunami (9.3)
12 killed in california
What plate margin is the Philippines on?
Destructive plate margin
Why does the Philippines experience earthquakes?
Philippine plate (oceanic) subducts below Eurasian (continental)
Oceanic plate gets stuck below continental
Pressure builds
When the pressure gets too much, they jerk and cause shallow and deep focus earthquakes
Name an example of an earthquake in the Philippines
Manilla 1990
Killed 6,000
Why does the Philippines experience volcanoes?
Philippines plate subducts below Eurasian
Oceanic crust is heated by friction
Sea water is dragged into the subduction zone causing wet partial melting
Magma is less dense than the continental
Crust is silica rich = explosive
Rises to the surface and forms volcanoes
Name an example of a volcano in the Philippines
Mt. Pinatubo July 1991
Killed 700
Why do landslides occur in the Philippines?
Demand for food/farmland has led to deforestation - heavy precipitation causes land slides
Earthquakes - Leyte island 2006, killed 1100
Why is the Philippines vulnerable?
Rapid urbanisation - slums
Fast growing economy but majority live on $3 a day
Poor preparedness - few emergency services/hospital beds, poor disaster management - susceptible to secondary impacts
Many live on inaccessible locations - small islands (7000+) or on slopes of volcanoes
Name an example of a typhoon in the Philippines
Typhoon Xangsone
250 deaths
$800 million in damages
What are the physical impacts of sea level rise on Africa?
Movements of environmental refugees from the countryside puts pressure on the coastal zones, especially North and West Africa
60% live in coastal zones
What are the physical impacts of changes in rainfall patterns on Africa?
More variable = competition between countries particularly along large rivers (Nile)
Scarcity increases - dependent on poor quality sources (increase in waterborne diseases - pressure on healthcare system)
Reduced period in which crops can grow
What are the human impacts of climate change on Africa?
Food scarcity - desertification due to pressure/ overgrazing on existing farm land
Health - famine and malnutrition will increase, placing Africa’s food security under threat
Debt - Africa is vulnerable due to debt crisis, most countries have debt written off and this affects majority of African countries - reduced through cash crops
Why is Africa vulnerable?
The countries tend to be among the least developed in the world and have weaker economies
Absolute poverty
Many are subsidence farmers - vulnerable due to rain fed agriculture
Low level of preparedness
