Hazards

Question 1

How is a Hadley cell formed?

Answer 1

1. Sun heats the air and it rises at the equator to create an area of low pressure at the earth’s surface
2. As air cools, it spreads out to the poles.
3. Cool air is dense and therefore sinks back to earth which presses down on the earth, creating an area of high pressure.
4. Air moves from high to low pressure, so air rushes in at ground level to replace the rising air.

Question 2

How is a Ferrel cell formed?

Answer 2

Air meets at low altitudes to ascend along the boundaries between cool polar air and warm subtropical air.

Question 3

How is a polar cell formed?

Answer 3

1. Dense cold air falls in polar regions creating areas of high pressure.
2. It then spreads to warmer altitudes.
3. As the air rises it expands and becomes lighter so continues to rise.
4. As the air rises, it cools down and spreads out again, north to south.

Question 4

What is pressure like in cold/warm air?

Answer 4

cold air = high pressure as it sinks

warm air = low pressure as it rises

Question 5

What is the ITCZ (Inter Tropical Convergence Zone)?

Answer 5

It is an area of low pressure that forms along and either side of the equator. Here the northeast trade winds meet the southeast trade winds. This results in a band of heavy rain around the globe..

Question 6

What is Britain’s climate?

Answer 6

Britain has a Maritime climate. A warm ocean current called the North Atlantic drift makes it warm and wet.

Question 7

What is an interglacial period?

Answer 7

warm periods between glacial periods like now.

Question 8

What is a glacial period?

Answer 8

Cold periods, some of which become ice ages.

Question 9

What is climate?

Answer 9

It is the average of weather conditions (day to day temperature, wind and rainfall), measured over 30 years.

Question 10

What was the Pleistocene period and what is the Holocene period?

Answer 10

Pleistocene = the last cold period ending 10,000 years ago.
Holocene = the warm period from 10,000 years ago to now.

Question 11

What is an ice age?

Answer 11

A time in which the polar ice caps are much bigger than today.

Question 12

What is the eruption theory?

Answer 12

The theory that big volcanic eruptions have changed the climate of earth. The ash and gas rise enough that they spread around the stratosphere by high level winds. This prevents light reaching the earth’s surface making it cooler.

Question 13

What is the sunspot theory?

Answer 13

A theory from Chinese astronomers who have recorded sunspots as the sun sometimes has many spots and sometimes has few. It is thought that this causes changes in climate as lots of spots means more solar energy is fired from sun to earth.

Question 14

What is the orbital theory?

Answer 14

The theory that the changes in the earth’s orbit cause changes in the amount of sunlight earth receives. It is thought that tipping and wobbling can cause changes in climate.

Question 15

What is the asteroid theory?

Answer 15

The theory that asteroid impacts alter the earth’s climate. Large asteroids can cause ash and dust being sent up into the atmosphere, blocking sunlight similar to the eruption theory.

Question 16

How are tree rings evidence of past climate change?

Answer 16

They vary in width according to CO2 volume in the atmosphere.

Question 17

How are historical records evidence of past climate change?

Answer 17

There is data and pictures of frozen landscapes not in human memory.

Question 18

How are ice cores evidence of past climate change?

Answer 18

Ice is in layers, like rock and in these layers are air bubbles which include carbon dioxide which can be measured to determine past climate.

Question 19

What happens to solar radiation from the sun?

Answer 19

Most is absorbed by the earth and some is reflected by the earth and atmosphere .

Question 20

What happens to the solar radiation absorbed by earth?

Answer 20

It is often reemitted as infrared radiation, which can be absorbed and reemitted by greenhouse gas molecules. Meaning, they can be sent back to earth, having a warming effect.

Question 21

How are tropical cyclones measured?

Answer 21

Using the Saffir-Simpson scale = wind strength and speed

Question 22

What hazards do tropical cyclones bring?

Answer 22

1. Strong winds which can destroy power lines, buildings, bring down trees…
2. Storm surges bringing flooding caused by high tides due to low air pressure.
3. Intense rainfall caused by thick dense clouds
4. Landslides as it can saturate heavy ground causing it to slump.

Question 23

Where do tropical cyclones develop?

Answer 23

In a large still ocean area that is very warm, this develops a body of warm air which causes a cyclone

Question 24

How do tropical cyclones develop?

Answer 24

1. Warm air currents rise from the ocean which is replaced by other air that also rises.
2. High volumes of water condense to produce cumulonimbus clouds.
3. Coriolis force causes rising currents of air to spiral round.
4. When it reaches a landmass, it loses its energy from the ocean so air pressure rises, winds drop rainfall decreases and it becomes a storm.

Question 25

What are the earth’s layers from centre to outer layer?

Answer 25

inner core, outer core, mantle, asthenosphere and crust

Question 26

What is the temperature, physical state and composition of the crust?

Answer 26

It is solid, made of granite and basalt and is air temperature to 900 degrees.

Question 27

What is the temperature, physical state and composition of the asthenosphere?

Answer 27

It is partially molten, made of Peridotite and is 900 to 1600 degrees.

Question 28

What is the temperature, physical state and composition of the mantle?

Answer 28

It is a solid made of peridotite and is 1600 to 4000 degrees.

Question 29

What is the temperature, physical state and composition of the outer core?

Answer 29

It is liquid made of iron and nickel at 4000 to 5000 degrees.

Question 30

What is the temperature, physical state and composition of the inner core

Answer 30

It is solid made of iron and nickel at 5000 to 6000 degrees.

Question 31

How are convection currents created?

Answer 31

Heat rises from the liquid outer core and mantle which convection current. They are strong enough to move tectonic plates.

Question 32

How do composite volcanoes form?

Answer 32

When two plates move together and where one plate is destroyed underneath another and produces magma under high pressure. This means it erupts violently

Question 33

What is the lava for composite volcanoes and what is produced?

Answer 33

Acidic, explosive, low temperature, high silica content, thick and sticky. It produces ash, lava bombs, smoke and steam.

Question 34

How do shield volcanoes form?

Answer 34

Two plates move apart and magma simply oozes out of the mantle making for gentile eruptions.

Question 35

What is the lava for shield volcanoes and what is produced?

Answer 35

Basic, lowly explosive, high temperature, very low silica content, low gas content, runny. Only lava is produced and quietly escaping gas.

Question 36

How is a conservative plate boundary formed?

Answer 36

They are formed when two plates slide past each other, friction between them causes rare but very destructive earthquakes

Question 37

How is a divergent plate boundary formed?

Answer 37

They are formed when two plates move apart, this causes magma to rise to the surface, forming lava flows and shallow volcanoes.

Question 38

How is a convergent plate boundary formed?

Answer 38

They are formed when two plates collide . The denser oceanic crust gets bent and pulled underneath, the continental plate, forming a subduction zone. This makes magma less dense so it rises. This means volcanoes and earthquakes are common.

Question 39

What is an earthquake?

Answer 39

It is a sudden release of energy under the ground when tectonic plates push past each other building up pressure.

Question 40

What is a tsunami?

Answer 40

It is an earthquake beneath the seabed creating huge waves. They start off small in the open ocean but slow down and build up when they approach the coast meaning wave height can increase to 30 METERS.

Question 41

How are earthquakes measured?

Answer 41

They are measured using the Richter scale with 1 being unfelt, 6 being moderate, 8 being major and 9 means huge devastation.