Flashcards
Geography - Global Hazards
Cards in this deck (30)
- 1Describe the circulation and the climate of a Polar cellAir cools and sinks, creating a belt of high pressure and a cold, dry climate
- 2Describe the circulation and the climate of a Ferrel cellCold polar air mixes with warm air and rises, creating a low belt of pressure
- 3Describe the circulation and the climate of a Hadley cellCool air sinks creating a belt of high pressure, as the air sinks it becomes warmer and drier
- 4Describe the circulation and climate of the Inter-tropical Convergence ZoneWarm air rises creating a belt of of low pressure, as the air rises it cools, clouds formed then produce precipitation
- 5Describe how the global circulation system causes extreme weather in areas of the worldA hot, dry climate is created where the Hadley and Ferrel cells meet which is why there are deserts
Unsettled weather when the cool air mixes with warm air where the polar and Ferrel cells meet creating a cold, wet climate - 6Describe how the Albedo effect impacts temperaturethe Albedo affects is how much a surface reflects or absorbs the suns rays. Polar ice has a high Alebedo affect compared to deserts as they absorbs more of the suns heat
- 7Describe how cloud cover impacts temperatureCloud cover reflects the suns rays. Although potential isolation is stronger at the Equator, thick clouds reduce the temperature. Cloud isolation is stronger closer to the tropics where there is less cloud cover
- 8Describe how ocean currents impact temperatureOcean currents can move heat around very easily. The UK is warmer than other countries in that latitude because it is warmed by the North Atlantic drift
- 9Describe how land and sea impact temperatureOn land isolation is concentrated on the surface. At sea isolation reaches further and it stays warmer for longer
- 10Describe how altitude impacts temperatureHigher up the air pressure is lower which makes temperature colder
- 11Describe the distribution of tropical storms and whether it has changed over timeMany Asian countries get hit by tropical storms and so does North America. Scientists believe that global warming is having an impact on the amount of tropical storms
- 12Describe the distribution of drought and whether it has changed over timeMany areas in the south of Africa are at risk form drought and also many areas in Asia. Scientists believe that the pattern of drought has changed over time, this could be due to changing rainfall and evaporation patterns
- 13Describe the formation of tropical stormsThe water in the ocean must be at least 26.5C and 60 meters deep, tropical storms form between 5-15 degrees N and S of the Equator so that the Coriolis effect starts the storm spinning.
- 14Describe how El Nino and La Nina formedEl Nino and La Nina are caused by changes in the sea surface temperature. When trade winds that blow from E to W are weaker, the surface temperature increases and causes the El Nino effect. When the trade winds are stronger if forms the La Nina effect
- 15Describe how El Nino and La Nina impacts the rainfall pattersWeaker trade winds result in less rainfall on the Australian/Asian edge and more on the N and S American edge, the La Nina effect reverses this
- 16Describe how the El Nino effect leads to droughtEl Nino takes away rain form the Australian and Asian area which increases the chances of drought
- 17Describe the Earths structure and how it involves convection currentsThe Earths crust is broken into sections of Tectonic plates with the mantle underneath it. After the mantle there is the outer core and then the inner core
- 18What is the definition of a constructive plate boundary?Plates are moving apart to create more land
- 19What is the definition of a destructive plate boundary?plates are moving towards one another, with one being forced under the other
- 20What is the definition of the collision boundary?Plates are moving towards each other and creating mountains
- 21What is the definition of conservative plate boundary?Plates are moving alongside each other with no land lost or gained
- 22Describe how tectonic plates moveScientists believe that tectonic plates move due to ridge push and slab pull. Ridge push is when new crust rises because it is warm and thin, creating a ridge, it pushes older crust away from the ridge. Slab pull is cooler and thicker than hot mantle and so it sinks into the mantle
- 23What is the definition of a hot spot?A hot spot is not on a plate boundary but where the oceanic crust is very thin as
- 24Describe what happens when an oceanic plate meets a continental plateThe denser oceanic plate is forced under the continental plate (subduction). A the point of collision the oceanic plate bends and a deep ocean trench is formed and the continental plate buckles and creates mountains. When the plate fold against each other lots of pressure can build up and be released as earthquakes. Also the water makes the partially melted mantle less dense so it could rise through the cracks and form an volcano
- 25Describe what happens when two oceanic plates meet eachotherThe denser plate will subduct under the less denser one, forming a deep ocean trench. Volcanoes can the form and could create new islands
- 26Describe what happens when to continental plate boundaries meetWhen two continental plate meet they collide and push against each other. The are both less dense than the mantle beneath them, therefor there is no subduction and so no volcanoes are formed, however the pressure that builds up can cause earthquakes
- 27Describe how the movement of tectonic plates creates a deep focus earthquakeDeep focus earthquakes start 70 - 700 km beneath the Earths surface. They are triggered where an oceanic plate is subducted under a continental plate (at destructive plate boundaries) They can me very powerful bet the seismic waves are spread out vertically so smaller areas suffer damage
- 28Describe how the movement of tectonic plates creates a shallow focus earthquakeShallow focus earthquakes start within 10 km of the Earths surface. They occur at conservative, collision and in the upper part of destructive plate boundaries. They are usually small and cannot be felt, however because the seismic waves are spread out horizontally they can cause damage over a large area
- 29Describe how the movement of tectonic plates can cause composite volcanoesSubduction at destructive plate boundaries can lead to volcanic activity. The partially melted mantle that rises is viscous and it contains seawater and hot gasses which builds up pressure. When it is released it erupts violently, the lava flows down while ash is also released, the alternate layers of lava and ash creates composite volcanoes
- 30Describe how the movement of tectonic plates can create shield volcanoesShield volcanoes are found at constructive plate boundaries where the mantle rises as the plates are pulled apart. This lowers the pressure on the hot rock, which partially becomes runny, it doesn't trap gas so the eruptions are gentle, it surfaces as runny lava which cools to form a gentle slope
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- Geography Flashcards on Geography - Global Hazards, created by Anna Lessore on 22/03/2018.
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- Anna Lessore
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