6.3 Climate change — mitigation and adaptationIB Environmental Systems and Societies SL: Subtopic test

1. 1
   Denmark has replaced much of its coal-fired electricity generation with wind power. Wind and solar together now supply more than half of the country's electricity, and the government aims to phase out fossil fuels in its energy system. Danish wind farms produce no carbon dioxide while generating electricity, but wind speeds vary, so other sources or storage are needed on calm days.

   (a)

   Decarbonisation of the economy means

   [1 mark]

   • Acapturing carbon dioxide from the air and burying it
   • Bplanting trees to remove carbon dioxide from the air
   • Cincreasing the use of carbon-based fuels that produce less ash
   • Dreducing or ending the use of energy sources that emit carbon dioxide and replacing them with renewable sources

   (b)

   Which change is an example of decarbonisation?

   [1 mark]

   • AReplacing a coal-fired power station with offshore wind turbines
   • BBuilding a higher sea wall to protect a coastal town
   • CUsing more air conditioning during heatwaves
   • DMoving farms to areas with more rainfall

   (c)

   Explain why replacing coal-fired power stations with wind turbines helps to reduce the enhanced greenhouse effect.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   Bangladesh is a low-lying country on the Bay of Bengal that suffers from cyclones, flooding and saltwater intrusion into farmland. It was one of the first countries to produce a National Adaptation Programme of Action (NAPA), in 2005. Measures it has used include building cyclone shelters, raising homes on earth platforms and growing salt-tolerant rice varieties.

   (a)

   Which statement correctly describes an adaptation strategy?

   [1 mark]

   • AIt reduces the amount of greenhouse gas emitted
   • BIt aims to reduce adverse effects of climate change and take advantage of any positive consequences
   • CIt removes carbon dioxide from the atmosphere
   • DIt replaces fossil fuels with renewable energy

   (b)

   What is the purpose of a National Adaptation Programme of Action (NAPA)?

   [1 mark]

   • ATo set limits on the carbon dioxide emissions of rich countries
   • BTo reduce the global use of ozone-depleting substances
   • CTo identify a country's urgent and immediate needs for adapting to climate change
   • DTo measure global temperature

   (c)

   Explain how cyclone shelters and salt-tolerant rice varieties increase the resilience of communities in Bangladesh.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A city emits 4.0 million tonnes of carbon dioxide equivalent per year: buildings 1.6, transport 1.4, industry 0.6 and waste 0.4. Its climate plan includes insulating older buildings (reducing building emissions by 25%), expanding electric buses and cycle lanes (reducing transport emissions by 20%) and capturing methane from landfill (reducing waste emissions by 50%). The plan does not include industry. The city council has set a target of a 25% cut in total emissions.

   (a)

   Calculate the total reduction in emissions that the plan would achieve, and express it as a percentage of the city's current emissions.

   [3 marks]

   (b)

   Evaluate the city's climate plan in relation to the council's target.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A government minister says: "Our country produces only 0.5% of the world's greenhouse gas emissions. Whatever we do makes no difference to the climate, so we should spend our money on adapting to climate change rather than on cutting emissions."

   (a)

   Explain why global action, rather than action by a few states, is needed to avoid catastrophic climate change.

   [6 marks]

   (b)

   Evaluate the minister's view that the country should concentrate on adaptation rather than mitigation.

   [6 marks]

   Total for question 4: 12 marks

End of questions