Topic 1 Flashcards
(29 cards)
How do tropical cyclones develop
Tropical cyclones can develop when the sea temperature is 26.5 degrees or higher and when the wind shear between higher and lower parts of the atmosphere is low.
What is the source area of most tropical cyclones
Between 5 and 30 degrees north and south of the equator. Any further from the equator and the water isnt warm enough.
What is a tropical cyclones source of energy
Cyclones intensify due to energy from the warm water
Examples of hazards from tropical cyclones
High winds, intense rainfall, storm surges, coastal flooding, landslides
Impacts of tropical cyclones on people
Unemployment increases becauses businesses are destroyed, shortage of food in poor countries because crops are damaged, people left homeless, people may drown in the strong currents created by floodwater and storm surges.
Impacts on the environment from tropical cyclones
Storm surges can erode beaches and damage coastal habitats like coral reef,
trees are uprooted by high winds which can damage or completely destroy wooded habitats.
What areas are physically vulnerable to tropical cyclones
Low lying coastlines are vulnerable to storm surge flooding as well as large waves, areas in the path of tropical cyclones are hit more frequently, steep hillsides may increase the risk of landslides.
Which areas are economically vulnerable
Poorer countries because people depend on agriculture which is often badky effected and people may not have insurance to cover the costs of repairing damage caused by cyclones.
The economic impact is often greater in richer countries as buildings are worth more money
Which areas are socially vulnerable to tropical cyclones
Poorer countries because : buildings are poorer quality, health care isnt good, little money for flood defences or trained emergency teams, harder to rescue people because of poor infastructure.
How can scientists predict where tropical cyclones will hit
Scientists can use weather forecasting and satellite technolog to monitor cyclones
How is a cyclones magnitude monitored
It is monitored by measuring its wind speeds
What defences can be made to prevent damage
Defences like Sea walls can be built along the coast to prevent damage from storm surges. Buildings can also be built to withstand a storm surge
What are the two case studies for tropical cyclones
Hurricane Katrina and Cyclone Nargis
Describe the earths core
The inner core is solid and the outer core is liquid, at the centre it is very dense, the temperature inside the core ranges from 4400-6000 degrees celcius
Describe the earths mantle
Made up of silicon based rocks, parts of the mantle are semi-molten (asthenosphere) and some parts are rigid. The temperature ranges between 1000 and 3700 degrees celcius
Describe the earths crust
Made up of silicon based rocks, there are two types of crust : continental and oceanic.
The continental crust is thicker and less dense and the oceanic crust is thinner and more dense
What is a convection current
Circular movements of semi molten rock that happen in the asthenosphere
What is a plate boundary
It is where tectonic plates meet
What is a convergent plate boundary
Convergant boundaries are where two plates are moving towards each other.
What happens at a convergent boundary
The denser oceanic plate is forced down into the mantle and destroyed, this often creates ocean trenches and volcanoes.
When two continental plates meet the plates collide and the ground is folded upwards to create mountain ranges
What is a divergent plate boundary
Where two plates are moving away from each other and magma rises from the mantle to fill the gap and cools creating a new crust
What is a conservative plate boundary
Where two plates are moving sideways past each other or moving in the same direction but at different speeds. Crust is not created or destroyed.
How are volcanoes formed at convergent plate boundaries
At convergent boundaries the oceanic plate goes under the continental plate as it is more dense, it is destroyed and a pool of magma forms, the magma rises through the cracks in the crust called vents, the magma erupts onto the surface forming a volcano.
How are volcanoes formed at divergent boundaries
The magma rises up into the gap created by the plates moving apart forming a volcano
