Climate Change

Question 1

How old is the Earth and when did the Quaternary period begin?

Answer 1

Earth is 4.5 billion years old and the Quaternary period(which is an Ice Age) began 2.6 million years ago

Question 2

How long do glacials and interglacials last?

Answer 2

100,000 years and 10,000 years

Question 3

Are we currently in a glacial or interglacial period?

Answer 3

Interglacial period

Question 4

What are some examples of proxy data and their reliability? [3]

Answer 4

• Glaciological; Vostok Ice Core goes back 400,000 years is an example of ice cores containing O2 isotopes to interpret past climate. Reliable and detailed(1 layer/year)
• Historical; records, paintings( Temperature Data since 1850s, recorded on thermometers). Reliable, but short-term and unevenly distributed.
• Sea Ice Positions; Sea ice forms around the poles in winter and melts during summer; by observing max+min. sea ice levels/year, we can tell how ocean temps are changing. Reliable but short-term.
• Biological; tree growth is influenced by tree ring width patterns; they generally produced 1/year and can estimate climate.

Question 5

What are the issues of proxy data? [3]

Answer 5

• Calibration; calibrating the readings to modern analogues is hard
• Timeframes; some records don’t go very far back at all compared to others
• Accuracy; can be hard to tell the true age of the data sometimes

Question 6

What evidence is there for natural climate change? [3]

Answer 6

Sunspots, volcanic eruptions, Milankovitch cycles

Question 7

What are sunspots? How long do they last? Is there an example?

Answer 7

• Dark patches on the suns surface which increase the amount of energy Earth receives from the Sun, causing it to warm up.
• They come in cycles of 11 years.
• The Little Ice Age(starting 1300) is an example.

Question 8

What are the Milankovitch Cycles and how do they affect Earth’s climate? [6]

Answer 8

• Eccentricity; Earths orbit slowly changes from circle to elliptical and back, causing variation in energy received from the Sun(think why).
• Obliquity; Earth’s axis tilts 2 degrees and back in a cycle. The greater the angle, the greater the energy the poles receive.
• Precession; A gradual change in Earth’s axis orientation affecting the relationship between the other 2 cycles.

Question 9

How do volcanic eruptions affect climate change?

Answer 9

Major eruptions can cause huge amounts of dust and Greenhouse Gases into the atmosphere, blocking sunlight, causing cooling. (Mt. Pinatubo released 20mil tonnes of SO2).

Question 10

What is the Natural Greenhouse effect? Is it normal?

Answer 10

• When greenhouse gases trap the Suns radiation and prevent it from escaping Earth, increasing global temperature.
• This is normal as it keeps it at a level sustainable for life.

Question 11

What is the enhanced greenhouse effect?

Answer 11

When humans put more Greenhouse Gases into the atmosphere, trapping more radiation and causing it to warm up too much.

Question 12

How do humans enhance the greenhouse effect? [3]

Answer 12

• Farming livestock which produces a lot of methane. (flooded rice paddies also do the same)
• Burning fossil fuels like coal, oil, petrol, which releases greenhouse gases into the atmosphere.
• Deforestation; trees take in CO2, so removing them increasing the amount of CO2 in atmosphere(also burning wood as fuel releases CO2).

Question 13

What are the global environmental impacts of Climate Change? [4]

Answer 13

• Temperatures are expected to rise by up to 4.8C by 2100
• Warmer temps = shrinking glaciers, causing sea level rise(600million live <10m above sea level).
• Shrinking sea ice leads to destruction of polar habitats.
• Bleaching of coral reefs due to global warming
• Changing precipitation+ extreme weather can cause crop shortages
• Species moving due to temp. changes leads to loss of biodiversity in some areas.

Question 14

What are the global economic impacts of climate change? [2]

Answer 14

• Rising temps affecting crop yields causes more money spent on agriculture, importing food(Predicted cost of $17 billion for Vietnam by 2050 and Africa crop yields drop by 22% by 2050)
• Climate Change leads to more extreme weather, so more money spent recovering+preparing for them(2003 heatwave cost Europe farming £10 billion)

Question 15

What are the global social impacts of climate change? [3]

Answer 15

• More extreme weather killing people(20,000 died in 2003 heatwave)
• Causes climate change refugees as they cannot inhabit former home due to CC( predicted 100 million by 2050)
• Droughts+Changing precipitation can cause lack of water supply like in Lake Chad(used by 30mil).
• Warmer climates can spread diseases like malaria into places like Europe(1.5mil U5s die per year to diarrhoea)

Question 16

What are the UK environmental impacts of climate change? [3]

Answer 16

• Increasing temperatures(SE predicted 3.9C increase by 2080)
• Winter rainfall predicted to increase
• Summer rainfall predicted decrease of 23% in South
• Extreme Weather + RSLs can cause flooding and loss of habitats like Saltmarsh.

Question 17

What are the UK economic impacts of climate change? [4]

Answer 17

• Low-lying areas can experience flooding(£120bil worth of infrastructure at risk)
• Can affect fishing industry by damaging fishing infrastructure due to storms, fish migration due to temp.
• Warmer temperatures can cause increase in tourism and boost UK economy and decline in areas like Cairgnorms
• Flooding due to extreme rainfall can cost UK a lot (£3.2bil in 2007)
• Can mean more crop growth like Vineyards(2014 grew 43% more than 2013 in UK wine sales)

Question 18

What are the UK social impacts of climate change? [3]

Answer 18

• Health services may have to treat more heat-related illnesses(predicted 9000 more salmonella cases by 2050)
• Many vulnerable elderly people live on coasts which are most at risk from flooding
• Will cause water shortages in SE where there is a higher population density.
• 2007 flood; 3 deaths, 1,800 homes destroyed, 50,000 with no electricity