World At Risk - Compulsory CS Flashcards
What process caused drought-like conditions in California over the last 2 years?
La Niña
Where do landslides commonly occur in California after a winter storm?
Steep gradients:
- hillsides burnt and erodes by wildfire
- coastal mountain terrain (San Francisco bay, Malibu, Santa Monica)
What do Santa Ana winds create?
Increased risk of forest fires in rural areas (e.g Los Angeles, Yosmite National Park)
When does advection fog occur?
When cool air from off-shore current drifts inland and meets warm air (esp. in Summer)
What areas are particularly at risk of EQs in California?
Areas along the San Andreas Fault, which extends ~810 miles through California.
Why is San Andreas (fault) so prone to EQs?
San Andreas is the conservative plate boundary between the N. American plate. Movement = sudden release of tension = EQ!
What is the probability that Mojave will have an EQ?
30% probability of a 7.5 magnitude EQ
Explain movements of 2 plates underneath California:
- Both N. American and Pacific plate moves in a NW direction ↖️
- BUT N.Am plate is moving faster than Pacific
- So relative movement = SE ↘️
Where are coastal areas particularly at risk of tsunamis?
On the edge of the ‘Pacific ring of Fire’
CA has had 14 tsunamis since 1812
How much of CA’s population is vulnerable?
19% (in 2013)
Quantify the rate of Pop. Growth in CA:
It has tripled in the last half of the 20th Century.
Protected to be 50 million by 2050.
Quantify the rate of urbanisation:
50,000 acres of farmland is lost to urbanisation each year.
~95% if California’s Pop live in urban areas.
How many people live in CA?
37.3 million
How many of CA’s pop. is affected by poverty?
1 in 4
Exemplify USA’s rapid rate of deforestation:
USA lost 6% more forests that any other country (2000-2005)
How quickly are Arctic temp.s rising?
Twice the rate of the rest of world
How will thawed permafrost effect ecology in the Arctic?
40% of permafrost is expected to thaw!!! ⛄️
Causing lakes to thaw, removing habitats for freshwater species (e.g ARCTIC CHAR )
How will increased UV radiation effect Arctic’s ecology?
Destroy phytoplankton at base of food chain
How have Artic fox numbers been affected and why?
Only 200 individuals left in Scandinavia - key source of food (Lemmings/voles) has declined due to lack of snowy conditions
- more completion for Red Fox which is spreading N.
How will global warming benefit agriculture in Artic
Longer growing season
Although poor souls will be a limiting factor.
How are Inuits affected by GW?
24 Inuit villages in Alaska are now threatened by flooding
Outline a potential social benefit of GW for Greenland:
- Increased access to gas/oil/minerals
- 25% of the worlds remaining resources are in Arctic
- 80% of pop. this will increase economic opportunities
How much has Africa warmed up since 1900?
The continent is 0.5C warmer
Quantify rate of soil erosion in Ethiopia’s Highlands:
1.5 tonnes erode each year with a potential loss of 1.5 MILLION tonnes of grain!!
How will areas affected by malaria change due to climate change?
Area affected by malaria is expected to double so that 5.2 Million people are affected.
How will African subsistence farmers be affected?
70% of Africa’s Pop. (85% in Libya) will experience less/unreliable rainfall as temps rise.
Directly impacting food supply
What %age of California is in extreme drought?
80%
What are the Philippines main hazard? How often does this Hazard occur?
Typhoons - 20/year
How many active volcanoes lie in the Philippines?
17!
What are Lahars? How many have been affected?
They are mudflows which result from volcanic EQs - 100 killed by Lahars in Pinatubo
Describe plate boundary at the Philippines:
- Destructive plate boundary
- Philippine plate; dense oceanic subducted at a rate of 3cm/year beneath Eurasian plate.
- Eurasian plate: lighter continental plate
How common are landslides in mountainous areas of Philippines?
V. Common: 3000 people have died due to landslides in past 100 years.
What %age of Philippines are at risk from EQs?
100%
What is the population density of Manila?
The megacity had a pop. density of 2000/km2
Quantify %age of young dependants in Philippines:
45% of pop. under 18 years - rapid population growth
How is Phlippines economy affected by droughts?
El Niño (2010) = ~2.5 million tonnes of rice/corn lost = agricultural loss of $US 33 Million!
What does rapid urbanisation on Philippines lead to?
Creation of slums:
- 20 Million live in slums
- 1/10 lives in Manila
