Hazardous Earth

Question 1

Explain why low latitude locations receive more heat then places close to the poles

Answer 1

Earth is largely spherical so more radiation is received at the equator, the hottest part of the earth, where the poles are the coldest part of the earth

Question 2

Latitude

Answer 2

Horizontal line;measurement of distance from the equator which ranges from 0° at the Equator to 90°

Question 3

Longitude

Answer 3

Vertical line;measurement of distance from the equator which ranges from 0° at the Equator to 90°

Question 4

How does atmospheric circulation causes high pressure areas (dry) like Tindouf

Answer 4

Areas of high pressure are caused by descending air from Hadley and Ferrell cells. As air cools it descends leading to high pressure at the surface. Also the air is descending, which reduces the formation of clouds and leads to light winds and settled weather conditions

Question 5

How does atmospheric circulation causes low pressure areas (wet) like Singapore

Answer 5

Areas of low pressure are caused by ascending air from two Hadley cells. As air warms it ascends leading to low pressure at the surface. Water vapours condense forming clouds and perhaps precipitation. Weather in depression area is often unsettled

Question 6

Atmospheric circulation cells

Answer 6

• Hadley cell
• Ferrel cell
• Polar cell

Question 7

How is heat transferred

Answer 7

Winds blow from areas of high pressure to areas of low pressure, transferring heat away from equator

Question 8

How do atmospheric circulation cells move heat around world

Answer 8

Winds are part of global atmospheric circulation cells. cells have warm air rising which creates a low pressure belt and cool falling air which creates high pressure be

Question 9

Four different factors that cause climate to change over last 400,000 years

Answer 9

Orbital changes

Volcanic activity

Solar output

Asteroid collisions

Question 10

Orbital stretch

Answer 10

Earth orbital path around sun changes from almost perfect circle to ellipse (oval shape) and back every 96000 years

Question 11

Orbital tilt

Answer 11

Earth axis is tiled at angle as orbits sun. Tilt changes over cycle of 22000 years

Question 12

Volcanic activity effect on climate

Answer 12

Major volcanic eruption ejects large quantities of materials,e.g ash, into atmosphere.

Some of the particles reflect the Sun’s rays back out to space, the earth gets cooler

Example if this is eruption of Mount Tambora in Indonesia in 1815 with lead to a year without summer

Question 13

How do ice cores in Antartica tell us about previous temperatures

Answer 13

By analysing the gases (e.g carbon dioxide) trapped in the layers of ice, you can tells the temperature was each year

Question 14

Greenhouse gases

Answer 14

Water vapor (H2O)
Carbon dioxide (CO2)
Methane (CH4)
Nitrous oxide (N2O)
Ozone (O3)

Question 15

Factors that show climate change is happening

Answer 15

Sea level
Since 1901 sea levels have risen by almost 0.2m.Water in the ocean expands as it gets warmer, this is called thermal expansion

Global temperatures
Temperatures have increased by nearly 1 degrees since 1880 and expected to rise by 0.3-4.8 depress between 2003 - 2100

Question 16

3 consequence of climate change

Answer 16

Some areas in world could become so hot and dry that it can be difficult or impossible to inhabit

Lower crop yields could increase malnutrition, ill health and death from starvation, particularly in lower latitude countries

Some farmers in higher latitude countries benefit

Question 17

Astroid collision impact on climate

Answer 17

Astroid hutting the earth’s surface can launch huge amounts of dust into atmosphere

Question 18

Orbital wobble

Answer 18

(Also called precession) the axis of Earth wobbles like a spinning top every 2200 year cycle

Question 19

How have humans enhanced greenhouse effect

Answer 19

Industrial
Some industrial processes also release greenhouse gases,e.g cement is made from limestone, which contains carbon. When cement is produced lots of CO2 is released

Industrial waste may end up in landfill sites where it decays, releasing CH4

Farming
Farming of livestock produces a lot of CH4

Rice paddies contribute, as flooding fields emit methane

Question 20

What is Tropical cyclone

Answer 20

Tropical cyclones are circular in shape hundreds of kilometres wide and usually last 7-14 days

Spin anticlockwise in northern hemisphere and clockwise in southern

Center of cyclone is called eye, low pressure, no clouds, no rain and high temperature in eye

Eye is surrounded by eyewall, strong winds(around 160km per hour) storm clouds and low temperature

Question 21

Formation of Tropical cyclone

Answer 21

Source area of most cyclones is between 5* and 30* north or south of equator, any further from equator and water isnt warm enough. When sea temperatures are 26.5*C or higher and when wind shear(difference in windspeed) between higher and lower parts of the atmosphere is low. Warm, moist air rises and condensation occurs. This releases huge amounts of energy, which makes the storm powerful. The Earth’s rotation deflects the paths of the winds which causes the cyclone to spin.

Question 22

How do cyclones intensify in energy

Answer 22

Cyclones intensify due to energy from the warm water.

Question 23

How do cyclones dissipate

Answer 23

When moved over land or cooler water

Question 24

Tropical cyclones cause physical hazards

Answer 24

Wind speeds can reach 250km/h

Tropical cyclones can releases trillions of litres of water per day as rain. Rain gets heavier closer to eye

Storm surge is a large rise in sea level caused by low pressure and high winds

Flooding happens as a result of storm surges and strong winds driving large waves to shore

Question 25

Tropical cyclone impact on people

Answer 25

People may drown in strong currents

Wind speeds in tropical cyclones can destroy buildings leaving people homeless and jobless

Damaged roads make it very difficult for aid and emergency vehicles to get through

Question 26

Tropical cyclone impact on environment

Answer 26

Trees are uprooted by high winds which can damage or completely destroy wooden habitas

Storm surges can erode beaches and damage costal habits (e.g coral reefs)

Flooding caused by storm surges can pollute freshwater environment with saltwater

Question 27

Most vulnerable to tropical cyclone

Answer 27

Physical
Low-lying coastlines are vulnerable to storm surge flooding as well as large waves caused by high winds

Steep hillsides may increase the risk of landslides

Economic
Poor countries are vulnerable as:
Many people depend on agriculture which is often badly affected, leading to loss of livelihood

People may not have insurance to cover costs of repairing damage and infrastructure

Social
Poor countries are vulnerable as:
Health care isnt as good for flood defence so they struggle to treat all casualties

Harder to rescue people because poor infrastructure

Question 28

Solar output

Answer 28

Suns output of energy isnt constant. Changes in short cycles of 11 years and possibly longer cycles

Reduced solar output can change climate may causing mini ice age

Example- Maunder Minimum was a period of reduced solar output between 1645 to 1715 causing mini ice age

Question 29

Convection current

Answer 29

When lower parts of the asthenosphere heats up they become less dense and slowly rise

As they move towards top of asthenosphere they cool down becoming more dense then slowly sink

This drags on base of tectonic plates and moves them

Question 30

Convergent boundaries

Answer 30

Two plates are moving towards each other

Where oceanic plate meets continental the denser oceanic plate is subducted into mantle and destroyed

When two continental plates meet the plates collide and ground is folded and forced upwards to create mountain ranges

Question 31

Divergent boundaries

Answer 31

Where two plates are moving away from each other, e.g mid-Atlantic ridge. Magma rises from the mantle to fill the gap and cools creating new crust

Question 32

How is a volcano formed

Answer 32

A volcano is formed when magma rises from inside the earth and erupts onto the surface.

Question 33

Convergent boundary

Answer 33

Where two plates move towards each other

If when oceanic plate meets continental plate, the denser oceanic plate is forced down into mantle and destroyed. This often creates volcanoes and ocean trenches

If when two continental plates meet the plates collide and the ground is folded and forced upwards to create mountain ranges

Question 34

Divergent Boundaries

Answer 34

Where two plates are moving away from each other e.g mid-Atlantic ridge. Magma rises from mantle to fill the gap and cools creating cracks

Question 35

Conservative boundary

Answer 35

Where two plates are moving in the same direction but at different speeds e.g along west coast of the USA. Crust isnt created or destroyed

Question 36

Volcano formation/Divergent plate boundary

Answer 36

The magma rises up into the gap created by the plates moving apart forming a volcano

Question 37

Volcano formation/Convergent plate boundary

Answer 37

Oceanic plate moves down into mantle where its melt and destroyed. A pool of magma is formed rising though vents in the crust. Magma erupts onto the surface, now called lava, forming a volcano

Question 38

3 ways earthquakes occur

Answer 38

convergent boundary
divergent boundary
conservation boundary

Question 39

What are earthquakes

Answer 39

Shockwaves caused by movement of plate boundaries

Question 40

How are earthquakes measured

Answer 40

Using moment magnitude scale