Dynamic Planet

Practice questions: 2016

You have 1 hour 15 minutes for this paper. That is about

12 minutes per question.

Answer questions 1-4Restless Earth, Changing Climate, Battle for the

Biosphere and Water World

Answer question 6 – River Processes and

Pressures. NOT question 5. Answer question 7 –

Oceans on the Edge. NOT question 8

There are marks for spelling, punctuation and grammar. Make sure you write in full

sentences and check these things.

Volcanoes- Type of volcano: Shield volcanoes are less explosive

but lava travels a long way causing damage to buildings and farmland. Composite (cone) volcanoes (e.g. Montserrat) are explosive. They often produce poisonous gases and pyroclastic flows which are very dangerous to humans and property

- Location: If it is close to a major urban area where people live (e.g. The eruption in Montserrat destroyed Plymouth the capital city).

- Development: More developed countries will be able to afford warning systems (e.g. tilt meters) to warn people. They will also have better evacuation plans and drills

Earthquakes- Magnitude: the strength of the earthquake- Depth: Shallow earthquakes are more destructive

(e.g. in Haiti)- Distance from epicentre: Haiti earthquake

epicentre was close to Port au Prince the capital city so destructive

- Time of day: Whether people are out in large numbers

- Development: Quality of building control design- Preparation: The quality of the emergency services

and education / preparation of the population- Secondary impacts: E.g. Japan had a tsunami and

fires

Chances Peak: Montserrat

Primary impacts:- 23 people died and many homes were destroyed.

This led to people on the island being evacuated to the North were it was safe.

- Destruction of Plymouth (capital city) – It was covered in ash and pyroclastic flows

- Destruction of the islands crops by ash- Infrastructure was destroyed

Secondary impacts:- People suffered from health problems due to the

ash- People lost jobs as tourism declined on the island- Montserrat was left with an ageing population as

many young people moved away from the island

Explain why some volcanoes / earthquakes have a greater impact than others. (6 marks)

Explain the primary and secondary impacts of a volcano you have studied (6 marks)

Question 1) Restless Earth

• Orbital changes – From a circular to an oval orbit can affect the amount of sunlight / heat the earth receives

• Sun spots - Increased sun spot activity leads to higher amounts of heat reaching the earth

• Volcanic eruptions – Ash can block out the sun reducing temperatures

• Meteorites – Impacts can throw up clouds of dust blocking out the sun and reducing temperatures

• Transport – Cars, planes release carbon dioxide (a greenhouse gas) into the atmosphere making the greenhouse gas layer thicker, therefore trapping more heat.

• Factories and power stations using fossil fuels release carbon dioxide and increase the greenhouse effect

• Deforestation – Trees absorb CO2 through photosynthesis. Cutting down trees prevents further CO2 from being locked away. Many of the trees are also burnt, releasing CO2.

• It is difficult because we don’t know the future size of the world population, or what the greenhouse emissions of a future population will be, e.g. the amount of fossil fuels they will use.

• We are unsure of how quickly different countries will develop. This will influence their resource consumption (and e.g. car ownership). E.g. China’s rapid development has increased it’s CO2 emissions, if other countries develop as quickly there will be a great impact on climate change and rising global temperatures.

• The switch to renewable energy is hard to predict. If countries use more renewable energy (e.g. HEP) it will reduce CO2 emissions and temperatures will not rise so fast.

• The growth of the ‘Green Economy’ in jobs such as recycling could reduce resource consumption and therefore carbon emissions.

• Other factors such as melting ice in the Artic could increase the rate of temperature rise as there will be less ice to reflect the sun’s rays back to space. It could also melt ice which is trapping Methane (a greenhouse gas) in permafrost.

Outline reasons why predicting future global temperatures is difficult. (6 marks)

Question 2) Climate and Change

Examine how degradation of the biosphere takes place by indirect means, including the impact of climate change on tropical rainforests. (4 marks)

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• Climate change – caused by increased CO2 emissions and deforestation will impact on rainforest ecosystems:

• Lower rainfall could result in the ecosystem changing to savannah grasslands. This would affect the biodiversity and animals able to survive / adapt.

• Wildfires would become more common with hotter, drier weather

• If rainforests started to disappear climate change would become worse as they store large amounts of carbon and photosynthesise carbon dioxide into oxygen.

• National Parks – protecting areas from development . This helps protect the biodiversity in the Amazon rainforest

• Eco-tourism – Tourism based on the protection of the environment. Tourist numbers are low and do not negatively impact on wildlife and habitats.

• Sustainable industries – e.g. logging industries replanting trees, or vines being used to make baskets. E.g. no lasting damage to the rainforests

• International Agreements – CITES (Convention on International trade in endangered species) prevents trade in endangered animal goods and helps protect animal species. World Heritage sites are protected by the UN and governments

Difficulties and tensions can exist when managing the biosphere.- People want to make money from the biosphere, this often involves it’s destruction (e.g. logging or mining). This would help developing countries earn money and create jobs (e.g. Brazil). Protecting the rainforest also costs money, which for a developing country like Brazil, would otherwise be spent on healthcare or education. However destroying the rainforest is not sustainable and resources will not last in the future if they continue to be consumed. Therefore the rainforest needs to be managed sustainably to preserve the environment although allowing people to still earn a living. E.g. through eco tourism or sustainable industries.

Question 3) Battle for the Biosphere

Aswan Dam, EgyptCosts (negatives)• Nubian people – 12,000 forced to leave their

homes because the land was flooded for Lake Nasser.

• No more silt is deposited on the land (making it fertile). Farmers no have to pay for fertilisers (these are expensive and cause pollution)

• Water snails are no longer washed out to sea. They spread Bilharzia disease

Benefits (positives)• Water can be used to irrigate land all year• Villages are safe from flooding• The dam produces hydro-electricity (renewable

energy) for villages

Using examples, explain how humans can disrupt water supplies. (6 marks)- The Aswan Dam in Egypt has disrupted water

supplies by creating Lake Nasser (a reservoir). This has increased water supplies in the region. Although it has reduced flooding downstream, there is also lower flow which can disrupt ecosystems.

- Over-extraction of groundwater in Mexico City, Mexico has reduced groundwater supplies for the future. It has also resulted in subsidence in the city.

- Deforestation in the Amazon Rainforest has resulted in less interception. This has disrupted water supplies as flooding is now more common.

- Cloud seeding in China has increased precipitation at certain times. This however disrupts water supplies elsewhere as it reduces precipitation in other places. Explain how climate change can disrupt

the hydrological cycle. (6 marks)- Warmer temperatures in some parts of the world will increase evaporation, leading to increased rainfall and less

water in storage (lakes, ice caps, soil)- A warmer climate will also increase melting from glaciers and ice caps. This could increase flooding, but will also

increase fresh water supplies (in rivers).- Some areas will become drier, although wild weather could lead to increased surface runoff and flash flooding

(on hard, dry ground).

Question 4) Water World

Hydrograph 1 is more of a hazard as it has a shorter lag time (time between peak rain fall and peak discharge). This would mean people have less time to prepare, and evacuate from the flood.

A short lag time is often due to urbanisation. This creates impermeable surfaces, reducing infiltration and increasing surface runoff. Therefore leading to a greater, and faster peak discharge. Deforestation would have a similar effect as interception would be reduced.

Question 6) River Processes and Pressures

E.G. Sheffield – Hard Engineering• Hard Engineering - Used to control nature. They are

usually expensive and can have a negative impact on the environment.• Embankments / Levees – Used along the River Don

to raise banks and increase the size of the river channel. It prevents flooding as the river can hold more water

• Straightening the river – To allow more water to flow through the river channel quickly. This would help remove flood waters

• Overflow channels in Sheffield – To carry floodwaters to safe locations when the discharge is too high

E.G. River Skerne – Soft Engineering• Soft Engineering - A more sustainable approach, as it

works with nature. It will also help the local environment and is cheaper.• Afforestation – Planting trees on the flood plains

increases interception and reduces surface runoff. It also creates habitats

• Landuse zoning – Restricts building on the floodplain and therefore the damage done if the river floods.

• Flood warning systems – To inform people if there is a risk of flooding and therefore reduce the risk to them.

E.G. Sheffield• Physical (natural)

• Prolonged, heavy rainfall which leads to saturated soils which can absorb no more moisture. This increases surface runoff and flooding.

• Steep slopes meant that the rainfall had little time to infiltrate so flowed down hillsides as surface runoff causing flooding

• Point of confluence. Sheffield is at the confluence of the River Don, Loxley and Sheaf. This meant there was a large discharge from the 3 rivers resulting in flooding.

• Human• Urbanisation (in Sheffield) reduced infiltration

and interception increasing surface runoff and flooding

• Deforestation reduces interception and increases the risk of flooding

• Burst levees and blocked drains resulted in flooding being made worse in Sheffield

Question 6) River Processes and Pressures

• Increased sea temperatures will lead to coral bleaching, (where corals expel the algae living on them). It turns white and becomes brittle and easily broken. This results in a loss of habitat. The loss of plankton also affects the food chain.

• Climate change will lead to rising sea levels. This could submerge coastal ecosystems such as mangroves. It could also make affect fragile coral reefs with deeper water levels

• Climate change could result in a greater number of storms. This could break fragile corals.

• Changes in temperature could lead to biodiversity changes as animals cannot adapt to rising temperatures. This would effect the food chain.

• Warming seas have led to species migration. E.g. Dangerous species like the Portuguese man o’ war jellyfish have now been found in the North Atlantic. This can disrupt fragile food webs and ecosystems

E.G. Ban Don Bay, Thailand (Coral Reef)• Environmentalists and tourists will disagree about how to manage the

coral reef.• Environmentalists would want the use of the reef to be restricted

and areas zoned to avoid lasting damage. Tourists would want to visit the reef and take souvenirs (coral) from it. They would also want to eat tropical fish caught from the reef, although the fisherman may have used destructive fishing techniques like dynamite fishing which the environmentalists would disagree with.

• Local people would disagree with the environmentalists as tourism would provide jobs and incomes, which would need the coral reef to be exploited.

E.G. The North Sea • Fisherman and environmentalists disagree about the management of

the North Sea• Environmentalists would like to see more ‘no-take zones’ in order

to allow fish stocks (of Cod) to replenish.• They would also like to see trawler boats banned as they damage

the sea floor habitats and often have large amounts of ‘bycatch’ which has a negative impact on the food chain.

• Fisherman disagree because they need to make a living by catching cod in the North Sea and if they are unable to fisherman from other European countries will only catch the Cod instead.

E.G. Global Oceans (e.g. Pacific)• Many countries have disagreed about international agreements such as

the International Whaling Convention (IWC), which bans whaling. Japan and Norway have defied the ban and the Faroe Islands still continues to hunt whales as part of it’s traditional cultureQuestion 7) Oceans on the Edge