Physical Case Study Flashcards
River exe location
South west England
Rises in the moorland of exmoor and travels 82.7km to reach sea at ex mouth
River exe catchment
601km
Why has the river exe got a large drainage density
Largely underlain by impermeable rock (84%)
How much of the catchment is grassland
67%
Annual rainfall for river exe
1295mm of rainfall annually
Land use % for river exe
67% grassland - farmland
15% woodland
10% arable land - crops
3% moors and peat bogs
How far above sea level is the source of river exe
514 metres
Location of Amazon rainforest
Covers large areas in the north of South America
Lies between cancer and Capricorn
Aprox 15•n to 15•s of equator
Size of Amazon rainforest
4% of earths surface
Climate of Amazon rainforest
27•C and roughly 2000+mm of annual precipitation
Amazon impact on carbon cycle
Accounts for 30-50% of global photosynthesis
Biodiversity of Amazon rainforest
Home to almost 20% of species on earth
Amazons impact on earths water
15% of global ocean water comes from the Amazon
Water cycle in Amazon
50% is used by plants and returned to the atmosphere
80% of rainfall is intercepted
Cause of deforestation in Amazon
Agriculture - 80%
Logging - mahogany
Road building - trans Amazon highway
Mineral extraction
Energy development
Settlement and population growth
Change in the Amazon
The Amazon basin has lost 17% of its primary rainforest in the last 50 years
Overall impacts of deforestation on the water cycle
Reduced evapotranspirstion
means less precipitation
Increased rates of runoff due to less trees
Soil is at risk of erosion which limits re growth
Mitigation on Amazon
Deforestation slowed by 75% between 2000 and 2021
Cattle ranching ban
Threat of prosecution
Protected areas
2006 soy moratorium
Eyjafjallajokull background
Constructive plate margin
North American and Eurasian plate diverge at a rate of 10-50 mm/year
Eyjafjallajokull nature of vulcanicity
Type of lava - basaltic
Viscosity - low
Shape - gentle sides, wide base, shield
Magnitude of eruptions - explosive
Hazards - ash, tephra, little lava, flooding
Primary impacts of Eyjafjallajokull
270 million cubic meters of ash ejected
110 million cubic meters of tephra
Very little lava
No deaths or injured
700 people evacuated
Secondary impacts of Eyjafjallajokull
Ash contaminated water supplies
20 farms were destroyed
150m thick ice cap was melted causing floods
2 bridges burst
Nepal earthquake of 2015 (Gorkha)
Magnitude -7.8
Date - April, 2015
Depth / focus - 15km - very shallow
80km north-west of Kathmandu
Vulnerability of Nepal to gorkha earthquake
Nepal GNI is £2730 per capita- its an lic
Kathmandu lies in a valley
Kathmandu has high population density
Infrastructure is poor
Impacts of gorkha earthquake
9000 fatalities
23,000 injuries
700,000 homes destoyed
200 killed in langtang landlides
5.17bn damage
Responses to gorkha earthquake
90% of Nepal’s military were deployed
The UN immediately released £15m
NGOs such as unicef brought in supplies