P1 - Unit 1A - Climate Change

Question 1

How old is the earth believed to be?

Answer 1

4 billion year old

Question 2

Which era is the Quaternary period in?

Answer 2

Cenozoic

Question 3

The Quaternary period is split into which two epochs?

Answer 3

Holocene

Pleistocene

Question 4

What has happened to the earths climate in the past?

Answer 4

The earth has swung between glacials (colder phases which have caused ice ages) and interglacials (warmer phases where the ice has retreated).

Question 5

What do glacial and interglacial episodes mean?

Answer 5

A glacial is a cold phase which generate ice ages and interglacials are warm phases when ice retreat.

Question 6

What equipment does the Met office use to measure climate change?

Answer 6

Weather stations, satellites, weather balloons, radar, ocean buoys

Question 7

Give 2 reasons why sea levels have risen 19cm since 1900?

Answer 7

When freshwater ice from glaciers and ice caps melt and thermal expansion(when the water gets hotter it takes up more space)

Question 8

What’s the total ice loss in Antarctica and Greenland since 2002?

Answer 8

6,315 billion tonnes

Question 9

How can we measure temperature before the 1900s before we had thermometers?

Answer 9

Before 1914 scientists have had to make inferences(guesses) based on proxy data.

Question 10

How is pollen analysis proxy data?

Answer 10

Each plant species has a distinctive pollen grain and if it falls into an oxygen free environment(such as peat bogs) they resist decay. The change inpollen over different layers of bog indicate changes in climate.

Question 11

How is ice core analysis proxy data?

Answer 11

Ice cores contain small air bubbles. The CO2 levels can be recorded. Cold phases less CO2, warm phases more CO2.

Question 12

How is historical records proxy data?

Answer 12

Dairy entries, journal entries, newspaper reports and church records can include information on weather conditions .

Question 13

How is dendrochronology proxy data?

Answer 13

The analysis of tree rings. Evidence from tree ring growth has been used to study climate change because the rings are wider in warmer and wet years.

Question 14

How is glacial retreat proxy data?

Answer 14

Strong photographic evidence that the worlds glaciers have been retreating over the last 50-100 years.

Question 15

How is cover of artic sea ice proxy data?

Answer 15

Currently there’s 50% less sea ice over the Arctic Ocean than there was 30 years ago.

Question 16

What an example of proxy data ice cores?

Answer 16

Vostok ice core, Antarctica (goes back to 10,000 years ago)

Question 17

What an example of proxy data historical records?

Answer 17

Since 1873 there have been daily weather reports which have been documented in the U.K. As well as cave paintings and depth of grave digging in Greenland.

Question 18

What an example of proxy data dendrochronology?

Answer 18

Using tree rings from Bristlecone pines which live for 6000 years or more

Question 19

What an example of proxy data pollen analysis?

Answer 19

Pollen is widely distributed and produced in vast quantities, some pollen in east Africa goes back 3 million years

Question 20

What’s a limitation of dendrochronology?

Answer 20

The growth of the tree rings can be affected by other things than temperature such as;wind, soil properties, disease or pollution

Question 21

What’s a limitation of pollen analysis?

Answer 21

Pollen can be transported considerable distances by wind or wildlife

Question 22

What are the 3 milankovitch cycles?

Answer 22

Eccentricity
Axial tilt
Procession

Question 23

What is eccentricity?

Answer 23

This is the path by which the earth orbits the sun. The earths orbit isn’t fixed it changes from circular to mildly elliptical. A complete cycle from circular to elliptical back to circular again this happens every 100,000 years.

Question 24

What is axial tilt?

Answer 24

The earth spins on an axis causing night and day. This axis is currently at 23.5°. Over about 41000 years the tilt moves back and forth between two extremes 21.5° and 24°.

Question 25

What is procession?

Answer 25

This is the natural ‘wobble’ rather like a spinning top. A complete wobble cycle takes about 26000 years. The earths wobble is the reason for certain regions of the world to have very long days and very long nights at certain times of year.

Question 26

What is the general term for the three orbital changes?

Answer 26

The Milankovitch cycles

Question 27

What are three natural reasons for climate change?

Answer 27

• Milankovitch cycles
• Solar output
• Volcanic activity

Question 28

How is solar out put a reason for climate change?

Answer 28

The output of the sun is measured by observing sunspots on its surface. Sunspots are caused by magnetic activity in the sun which results in dark patches on the surface. Satellites record the solar energy output using radio meters (since 1978). Over the last 50 years solar output has barely changed and has even slightly decreased. Therefore solar output can’t be responsible for climate change since the 1970s.

Question 29

How is volcanic activity a reason for climate change?

Answer 29

Volcanic eruptions can temporarily cause climate change. When a volcano erupts it releases sulphur dioxide(which when mixed with water vapour creates a volcanic aerosol which reflects sunlight away, causing the earth to cool down), ash can be carried round the stratosphere for many weeks and carbon dioxide is released which contributes to global warming.

Question 30

What is the greenhouse effect?

Answer 30

It’s a natural process created by the earths atmosphere. It’s vital to life on earth without it the earth would be approximately 33°C cooler than it is today. It’s when the earth absorbs short wave radiation from the sun and emits long wave radiation.

Question 31

What’s the enhanced green house effect?

Answer 31

The long wave radiation is reflected back into the earths atmosphere by carbon dioxide and by burning fossil fuels the amount of carbon dioxide in the atmosphere is increased so more long wave radiation is reflected which causes the earth to heat up.

Question 32

What are some of the gases and sources of gases which are responsible for climate change?

Answer 32

CO2 -burning fossil fuels, transport, industry
Methane -rice farming, dairy farming
Nitrous oxide -farming fertilisers, transport
CFCs -fridges, Nike air trainers, polystyrene

Question 33

What is the keeling curve?

Answer 33

Since 1958 a group of scientists begun to regularly record carbon dioxide levels in the atmosphere. They took these readings on Mauna Loa, Hawaii to keep away from any local levels of CO2.

Question 34

How do humans cause climate change by carbon dioxide?

Answer 34

The increase in carbon dioxide is from;burning fossil fuels(coal, oil and natural gas) and deforestation.

Question 35

How do humans cause climate change by the manufacturing industry?

Answer 35

The amount of carbon dioxide produced has been increasing since the industrial revolution, 40% of global CO2 emissions are from industry. Even though MICs have become more efficient.

Question 36

How do humans cause climate change by transport?

Answer 36

Emissions from transport are climbing at more than 2% a year. It has increased due to the long distance and long flights people are willing to take. Also in places like china and India more people are driving as their development takes off.

Question 37

How do humans cause climate change by heating homes and generating electricity?

Answer 37

Fossil fuels are used in heating homes. They are also burnt in power stations to generate electricity. As the population grows and wealth increases people demand more energy.

Question 38

How do humans cause climate change by deforestation?

Answer 38

Trees absorb CO2 as part over photosynthesis. Over the last 250 years large amounts of trees have been felled to fuel economic development such as urban expansion, agriculture. By trees being felled they don’t remove as much CO2 from the atmosphere.

Question 39

How do humans cause climate change by agriculture?

Answer 39

Farming processes involve the production of greenhouse gases. Methane is a product of animal waste products, rice and dairy farming. Fertilisers add to the amount of nitrous oxide in the atmosphere. As the worlds population increases, more food is required and as countries wealth increases there is an increasing demand for meat.

Question 40

What are 4 problems caused by rising sea level?

Answer 40

• flooding in the Netherlands
• floods in Nile delta
• Pacific islands such as the Marshall Islands are likely to be submerged
• floods in Bangladesh, threatening millions of people’s lives

Question 41

What are 5 benefits of global warming?

Answer 41

• crops can be grown further north due to warmer weather
• fewer deaths/injuries due to cold weather
• central heating in northern areas won’t be needed as much
• higher rainfall increases rice yields
• Canadas north west passage may become ice free and can be used by shipping

Question 42

What are 5 problems of global warming?

Answer 42

• alpine ski resorts close down due to lack of snow
• reduced rainfall in rainforests due to deforestation
• drier conditions reduces cereal production
• parts of Africa may become drier and more prone to droughts, leading to starvation and civil war
• increase in tropical storms activity in the Caribbean and USA

Question 43

What is mitigation?

Answer 43

Mitigation strategies, whether local or global, deal with the cause of the problem.

Question 44

Mitigation strategy:

What is the IPCC?

Answer 44

Intergovernmental Panel on Climate Change
Most methods of mitigation need agreement of lots of different governments. This is done through the IPCC but progress has been very slow.

Question 45

Mitigation strategy:

How can the causes of climate change be reduced by alternative energy sources?

Answer 45

To reduce carbon emissions you can use:
-hydroelectric power, nuclear power, solar wind and tidal, geothermal, biomass
Although renewable energy is more is currently more expensive than fossil fuels, they don’t emit large amounts of CO2

Question 46

Mitigation strategy:

How can the causes of climate change be reduced by solar energy?

Answer 46

A typical home can save over a tonne of CO2 per year as there is no greenhouse gas emissions from solar panels. However at times when there is no sunshine such as night, solar energy can’t be relied on to generate electricity.

Question 47

Mitigation strategy:

How can the causes of climate change be reduced by carbon capture?

Answer 47

Carbon capture and storage(CCS)
CCS can remove CO2 from the open atmosphere by converting it into a liquid ‘supercritical CO2’ which is injected into sedimentary rock. An impermeable cap rock prevents it from escaping. The process of CCS is expensive and is unclear whether CO2 would remain trapped in the long run and it doesn’t promote renewable energy.

Question 48

Mitigation strategy:

How can the causes of climate change be reduced by planting trees?

Answer 48

Trees act as carbon sinks, removing CO2 from the atmosphere by the process of photosynthesis. They also release moisture into the atmosphere producing more cloud, reducing incoming solar radiation. The UK has a £24.9million project to reduce deforestation in Brazil.

Question 49

Mitigation strategy:

How can the causes of climate change be reduced by international agreements?

Answer 49

Climate change is a global issue and will effect the whole world and requires a global solution. There have been 3 meetings; 2005 Kyoto Protocol reduce carbon emissions by 5.2%, 2009 Copenhagen didn’t work and 2015 Paris Agreement it had 3 main points to keep global temeperature increase below 2°C, review progress every 5 years and provide financial help for LICs.

Question 50

What is adaption?

Answer 50

Where we make adjustments to our environment as changes caused by climate change take place and try to make populations less vulnerable. Adaption strategies are local.

Question 51

How can the effects of climate change be made more manageable by changing agricultural systems?

Answer 51

Although the effects of climate change are uncertain, agriculture will need to adapt to them. Some methods are; increasing irrigation and changing crops and varieties grown and the time of year they are planted. The cost of adapting to climate change is more difficult for poorer subsistence farmers.

Question 52

How can the effects of climate change be made more manageable by managing water supply?

Answer 52

Climate change has caused more severe and frequent droughts and floods. Future climate change will affect the current patterns of water supply, impacting the quantity and the quality of our water. Two ways water can be managed; reducing demand by things such as aerators and increasing supply by using sea water on a desalination plant.

Question 53

How can the effects of climate change be made more manageable by reducing the risk from rising sea levels?

Answer 53

Ways of adapting to rising sea levels are; constructing sea walls, building houses raised on stilts, restoration of costal mangrove forests, building houses on earth embankments(LICs), flood warning systems and constructing artificial islands so people can be relocated. Ultimately if the sea rises too much the entire population of the Maldives could be relocated to India or Sri Lanka. An example of a flood barrier is the Thames barrier in London which is to prevent sea water from flooding the city.