Tectonic And Weather Hazards And Case Studies Flashcards
What is the difference between oceanic and continental crust?
- Oceanic=Denser,Can be subducted,found underneath oceans, younger
- Continental=Older, lighter (doesnt sink), cannot be destroyed
What happens at a destructive plate boundary?
- An oceanic and continental plate collide
- Oceanic crust is subducted under the continental plate and melts in the mantle
- Volcanoes and mountains so usually the most erupt I’ve
What happens at a collision plate boundary?
- Two continental plates collide
- Neither can sink so they collide upwards and form mountains
What happens at a conservative plate boundary?
- Two plates move past each other
- As they move friction is created and eventually they get stuck
- When the pressure is released so is a lot of energy and an earthquake occurs
- No new land created
What happens at a constructive plate boundary?
- Plates move apart from each other and in the gap magma rises
- Makes new land in the form of a shield volcano
What affects the severity of a natural disaster?
- The strength of the event
- The number of people in the area at the time
- The amount of poverty in the main area
What are the four main management strategies for reducing tectonic risks and how do they help?
- Monitoring-Using equipment to give people adequate time to evacuate
- Prediction-Using the monitoring equipment to predict when the next hazard will strike
- Protection-Helps with fatalities and destruction
- Planning-Strategies on how to prevent decimation by earthquakes.
How do convection currents cause plate boundaries?
- Heat from the core rises
- When it hits the surface it drags the plates apart causing magma to rise
- The heat then goes back down
What is the global atmospheric model?
- A model showing the circulation of air and weather on Earth
- Following the premise that hot air rises, cool air falls and will travel back to the equator
What are the three cells that make up the global atmospheric circulation model and what are their features?
- Polar Cells- Smallest where cold dense air travels slightly then recirculates
- Hadley Cells- Largest near the equator
- Ferrel cells- Don’t work off temperature making steady weather
What is the weather like where air rises?
- Low pressure and lots of rain
What is the weather like where air falls?
- Clear skies and minimal rainfall
What does ITCZ stand for and what happens there?
- Inter tropical convergence zone
- Warm air is sucked towards the equator making it hotter
- This warm air rises carrying any moisture and forms Cumulonimbus clouds (Large clouds)
What do hurricanes need in order to form?
- To start over the ocean
- Ocean needs to be at least 60 m deep
- Ocean needs to be 26 degrees or warmer
Structure of a hurricane?
- Eye of the storm- Calmer, slower winds
- Everywhere else- High winds, rain , death.