Weather Hazards And Climate Change

Question 1

What does Global Atmospheric Circulation describe?

Answer 1

How air circulated around the world

Question 2

What are the global circulation cells? (Ordered from North Pole to South Pole)

Answer 2

Polar, Ferrel, Hadley, Hadley, Ferrel, Polar

Question 3

What occurs at areas of low pressure? - what are the conditions like at these areas?

Answer 3

Air warms and rises, leading to evaporation which forms clouds and rainfall

Question 4

What occurs at areas of high pressure? - what are the conditions like at these areas?

Answer 4

Air cools and sinks, preventing water from evaporating which leads to sunny and clear conditions

Question 5

Where in the world is hottest? - why?

Answer 5

Equator: The sun’s rays hit the surface at a right angle

Question 6

What are the conditions like at the equator? - why?

Answer 6

Conditions are wet because hot air rises, leading to low pressure

Question 7

What are the conditions like at the Tropic of Cancer? - why?

Answer 7

Conditions are sunny because the air is sinking, leading to high pressure

Question 8

Between which cells does the Tropic of Cancer lie?

Answer 8

The Tropic of Cancer is between the Ferrel and Hadley cells

Question 9

What are the conditions like at the polar front? - why?

Answer 9

There are wet and cloudy conditions because the air is rising which leads to low pressure

Question 10

How do the circulation cells distribute heat across the Earth?

Answer 10

The differences in pressure between different points on the earth cause winds which redistribute heat from the tropics across the planet

Question 11

How do ocean currents help keep the UK warm? Use an example.

Answer 11

GULF STREAM:
- Brings warm water from the Caribbean across the Atlantic Ocean to the UK
- Heat rises from the water and warms the winds blowing across the UK
- This keeps the UK 5’C warmer

Question 12

What’s the greenhouse effect?

Answer 12

A natural process which keeps the Earth warm

Question 13

Name the natural causes of climate change

Answer 13

Milankovitch Cycles
Solar radiation
Volcanism
Surface impact

Question 14

Define the Milankovitch cycles

Answer 14

Natural changes to the Earth’s orbit and position that affect the amount of radiation we receive from the sun

Question 15

Explain the 3 Milankovitch cycles (how they cause climate change)

Answer 15

ECCENTRICITY:
- Earth’s orbit changes over long periods of time
- When the orbit around the sun is more circular, its slightly warmer (INTERGLACIAL PERIOD)
- When the orbit around the sun is more elliptical it’s slightly cooler (GLACIAL PERIOD)

AXIAL TILT:
- Earth is tilted so the pole are 23 degrees from vertical which creates seasons
- Over approx. 40,000 years, the angle of tilt changes meaning when it’s tilted away from the sun we get warmer summers and colder winters

PRECESSION:
- Earth ‘wobbles’ on its axis when it rotates, changing the direction the axis faces
- This creates a greater difference in summer and winter
- Occurs over approx. 24,000 years

Question 16

Define solar variation and explain how it causes climate change

Answer 16

Solar Variation - Amount of radiation the sun produces over time

Periods of lower solar activity lead to GLACIAL periods, high solar activity leads to INTERGLACIAL periods

Question 17

Explain how Volcanism causes climate change

Answer 17

Large scale eruptions eject huge volumes of ash and dust into the atmosphere, partially blocking out solar radiation (leading to GLACIAL periods)

Question 18

Explain how Surface Impact causes climate change

Answer 18

Large cosmic material can impact Earth’s surface, ejecting large volumes of dust into the atmosphere which partially blocks out solar radiation
(leads to GLACIAL period)

Question 19

What are the human activities that produce greenhouse gases?

Answer 19

Industry
Transport
Energy
Farming

Question 20

How does Industry produce greenhouse gases?

Answer 20

• As levels of disposable income rise, there is an increased demand for the production of consumer goods (because more people can afford them)
• This leads to industry growth which requires more energy for the factories resulting in more fossil fuels being burnt

Question 21

How does Transport produce greenhouse gases?

Answer 21

• Cars are becoming more affordable and more people take flights over long distances
• This requires huge quantities of fuel, naturally increasing the fossil fuels burnt (greenhouse gases released)

Question 22

How does Energy produce greenhouse gases?

Answer 22

• Increasing population and new technology means an increased demand for electricity
• This requires energy made by burning fossil fuels which produce greenhouse gases

Question 23

How does Farming produce greenhouse gases?

Answer 23

• population growth has led to a higher demand for food production
• mechanisation = more fuel burnt
• Intensive farming of cattle = increased production of methane (which is a greenhouse gas)

Question 24

What are the negative effects of climate change? (on people and the environment)

Answer 24

Rising sea levels
Retreating glaciers
Lower crop yields

Question 25

Explain Rising Sea Levels and how they have a negative impact on the people and environment

Answer 25

• An increase in temperature causes land based ice to melting, adding to the amount of water in the oceans which makes the sea levels rise
• Places not too high above sea levels have serious risks of flooding
• E.g. The Maldives is a developing country that relies on tourism and the country’s infrastructure is under threat. Key attractions will become inaccessible (loss of employment in tourism). Groundwater supplies contaminated with sea water flowing onto the islands. Increased temperature in surrounding ocean may lead to bleaching = death of coral reefs (environmental)

Question 26

Explain Lower crop yeilds and how they have a negative impact on the people and environment

Answer 26

• Plants produce their own food by photosynthesis which animals use as a vital food source
• Global climate change can cause increases in temperature or decreases in sunlight which negatively affects photosynthesis
• These LOWER CROP YEILDS mean that large sections of the population could suffer from malnutrition (especially in developing countries)

Question 27

Explain Retreating Glaciers and how they have a negative impact on the people and environment

Answer 27

• melting of high mountain glaciers (e.g. Himalayas) can lead to flooding of the local area in the short term
• In the long term, with a smaller volume of ice available in the glacier, there may be water shortages as less water is produced by the glacier on a regular basis
• Also contributes to SEA LEVEL RISE globally

Question 28

Explain the UK’s Climate

Answer 28

• between 50’N and 60’N of the Equator
• Temperate climate
• Extremes of weather are uncommon
• Extreme weather events (e.g. tornadoes) are rare
• Frontal rainfall common throughout the year due to cool air from the north and warm air from the south meeting

Question 29

How has the UK’s climate changed over the last 1000 years? (+ its effects)

Answer 29

MEDIEVAL WARM PERIOD:
- Between 950 and 1100
- Temperatures in UK were high enough for grape vine growth and greater crop yields
- Population increased significantly due to milder winters and greater food availability (because of greater crop yields)
- Period increased solar activity and low volcanic activity across the world

LITTLE ICE AGE:
- 1600 to 1850
- temps low enough on occasion to freeze river Thames thick enough for people to walk on
- Extended winters meant crop failures
- Period decreased solar activity and increased volcanic activity

Question 30

How and why does Temperature, Prevailing Wind, and Rainfall vary in the UK?

Answer 30

Prevailing wind from the South-west has travelled over warm ocean so the air is warm and contains a lot of moisture
So, the prevailing wind releases this moisture as rain in western areas first, leaving the east much drier
South is closer to the equator so its’s warmer and receives more solar radiation than the north
North also has higher altitude = colder and wetter

Question 31

How does the UK’s Maritime Influence impact its weather?

Answer 31

UK surrounded by sea, meaning most of the air that reaches it contains large amounts of moisture = consistent rainfall throughout the year

Question 32

How do the Circulation cells impact the UK’s weather?

Answer 32

Located near the ‘boundary’ between the northern Polar and Ferrel cells
At this ‘boundary’ warm air from the south and cooler air from the north meet, leading to formations of depressions and unsettled weather

Question 33

Why does a higher altitude cause increased precipitation?

Answer 33

As air is forced to rise over high land it is cooled, causing more moisture in the air to condense and fall as precipitation

Question 34

Name an example of how varying altitude in the UK affects rainfall in different locations

Answer 34

Scafell Pike at 978m above sea level averages 178 days of rain/year
London at 35m above sea level averages 98 days of rain/year

Question 35

Why is the UK’s climate milder that expected for its latitude?

Answer 35

North Atlantic drift brings warm water to the UK from the Gulf of Mexico driven by prevailing wind