There has been an increase in the average global temperature in the last 150 years. Explain the human factors causing global warming.

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1 Question 1 There has been an increase in the average global temperature in the last 150 years. Explain the human factors causing global warming. (5) Question 2 Study Diagram Q2. Describe the possible consequences of global warming throughout the world. (4) Diagram Q2: Newspaper Extract Global warming is causing an increase in temperature throughout the World. In Scotland, some areas of Glasgow near the Clyde are in danger of serious flooding and the risk is only going to get worse because of climate change due to global warming. Question 3 (a) Describe the human factors that may lead to the global temperature projection shown in the diagram. (4) (b) Explain the possible consequences of global warming. (6) Diagram Q3: Global Warming Projection

2 Question 4 Look at Diagrams Q4a and Q4b. (a) Explain the human activities which have contributed to the changes in global air temperatures. (5) Diagram Q4a: Global air temperatures (b) Discuss the possible impacts of global warming throughout the world. (5) Diagram Q4b: Greenhouse gases, emissions by type Question 5 (a) Explain the physical factors affecting climate change. (4) (b) Evaluate the effectiveness of the strategies used to: (6) (i) reduce the emissions of greenhouse gases; (ii) manage the local effects of climate change.

3 ANSWERS Question 1: Carbon dioxide: from burning fossil fuels - road transport, power stations, heating systems and from deforestation (particularly in the rainforests) and peat bog reclamation/development (particularly in Ireland and Scotland for wind farms). CFCs/PFCs: from aerosols, air-conditioning systems, refrigerators, polystyrene packaging, production of aluminium, etc. Methane: from rice padis, landfill sites, (almost half of UK s methane emissions), animal dung, oil exploration, permafrost melting in tundra areas and belching cows. Nitrous oxides: from vehicle exhausts and power stations. Hydrofluorocarbons (HFCs): potent greenhouse gases used to replace CFCs in refrigeration, air conditioning and the production of insulating foams. NB there were 6 man-made greenhouse gases included in the Kyoto protocol (Carbon Dioxide, Methane, Nitrous Oxide, Hydro fluorocarbons, PFCs and Sulphur Hexafluoride). Many of these are more powerful as greenhouse gases than CO2. Question 2 Descriptions of possible consequences may include: Rise in sea level. More extreme weather (and more variable) including floods, droughts, hurricanes, tornadoes etc. Extension and retreat of vegetation by altitude and latitude. Melting of ice sheets/icebergs. Impact on wildlife eg extinction of species. Increase in diseases eg malaria. Change in length of growing season. Some areas will become wetter, others drier. Changes to ocean current circulation. Changes in atmospheric patterns linking to monsoon, El Nino, La Nina etc. Question 3 (a) Human factors Carbon Dioxide: from burning fossil fuels road transport, power stations, heating systems, cement production and from deforestation (particularly in the rainforests) and peat bog reclamation/development (particularly in Ireland and Scotland for wind farms). CFC/PFCs: from aerosols, air-conditioning systems, refrigerators, polystyrene packaging etc. Methane: from rice paddies, animal dung and belching cows. Nitrous oxides: from vehicle exhausts and power stations. (b)

4 Melting of the ice sheets/glaciers A rise in sea level with subsequent migration as islands and coastal areas are submerged. Loss of plant and animal habitats in these areas eg impact on polar bears which could lead to a loss of tourism/more problems in settlements as the bears scavenge instead of hunting on the ice. New transportation routes across the Arctic Ocean ie the North West Passage with resulting benefits to trade/previously ice bound coastal settlements. Extension of mineral exploitation into the Arctic with positive and negative consequences. Changing rainfall/temperature patterns Higher or lower rainfall/temperature and maybe more extreme weather depending on where you are with resulting increasing/decreasing crop yields, more floods/drought/hurricanes/tornadoes etc. Extension or retreat of vegetation (and associated wildlife) by altitude as well as latitude growing vines/sunflowers in Scotland, spread of malaria, the loss of the Cairngorm Arctic habitat etc. Change in ocean currents (EI Nino/La Nina). Change to the Atlantic Conveyor disruption of the thermohaline circulation. Question 4 (a) Carbon dioxide from burning fossil fuels road transport, power stations, heating systems, cement production and from deforestation, particularly in the rainforests where more carbon dioxide is present in the atmosphere and less being recycled in photosynthesis (1 mark) and peat bog reclamation/development (particularly in Ireland and Scotland for wind farms). (1 mark) CFCs: disused refrigerators release CFCs when the foam insulation inside them is shredded. (1 mark) The coolants used in fridges and air conditioning systems create CFCs which are safe in a closed system, but can be released if appliances are not disposed of correctly. (1 mark) Methane: from rice paddies to feed rapidly increasing populations in Asian countries such as India and China (1 mark), belching cows to meet increasing global demand for beef. (1 mark) Methane released from permafrost melting in Arctic areas due to global warming. (1 mark) Nitrous oxides: from vehicle exhausts and power stations. (1 mark) (b) Rise in sea levels caused by an expansion of the sea as it becomes warmer and also by the melting of glaciers and ice caps in Greenland, Antarctica, etc. (1 mark) Low lying coastal areas, eg Bangladesh affected with large-scale displacement of people and loss of land for farming and destruction of property. (1 mark) More extreme and more variable weather, including floods, droughts, hurricanes, tornadoes becoming more frequent and intense. (1 mark) Globally, an increase in precipitation, particularly in the winter in northern countries such as Scotland, but some areas like the USA Great Plains may experience drier conditions. (1 mark) Increase in extent of tropical diseases, eg yellow fever as warmer areas expand, possibly up to 40 million more in Africa being exposed to risk of contracting malaria. (1 mark)

5 Longer growing seasons in many areas in northern Europe for example, increasing food production and range of crops being grown. (1 mark) Impact on wildlife, eg extinction of at least 10% of land species and coral reefs suffer 80% bleaching. (1 mark) Changes to ocean current circulation, eg in the Atlantic the thermohaline circulation starts to lose impact on north western Europe, resulting in considerably colder winters. (1 mark) Changes in atmospheric patterns linking to monsoon, El Nino, La Nina, etc. (1 mark) Question 5 (a) Solar activity: variations in solar energy and sun spot activity can alter global temperatures. Scientists have shown that variations in sun spot activity follow an 11-year pattern. (1 mark) Scientists at Cardiff University have discovered that periods of low sun spot activity corresponded with colder ocean currents. (1 mark) This caused high pressure to build in the North Atlantic Ocean, blocking of warmer ocean currents, and subsequently caused more extreme winters, in 2010 and (1 mark) In the current cycle, a peak in sun spot activity was anticipated in 2013, but in fact there was more sun spot activity in (1 mark) Changes in the Earth s orbit and tilt: Milankovitch s research suggested that every 41,000 years there is a change in the tilt of the Earth s axis. A greater tilt means more sunlight in polar regions and colder temperatures. (1 mark) Over a 97,000 year cycle, the Earth s orbit stretches from circular to eliptical, affecting the amount of energy received. (1 mark) Volcanic eruptions: Dust particles in the atmosphere after violent eruptions reduce the Earth s temperatures by shielding the Earth from incoming solar radiation and reflecting energy. (1 mark) This was apparent when Mount Pinatubo erupted in 1991, sending millions of tonnes of ash and gas 21 miles high into the atmosphere, resulting in average temperatures falling by up to 0 5⁰C. (1 mark) Ice cap/sheet melting: Melting of ice caps releases additional fresh water into the oceans, which in turn alters oceanic circulation with cold and warm ocean currents being affected. (1 mark) (b) For reducing emissions of greenhouse gases: At a local level, individuals are encouraged to reduce, reuse and recycle products so that less refuse is sent to landfill sites. The amount of waste being received at landfill sites has fallen dramatically, which shows that council policies and education campaigns have been effective. (1 mark) To reduce the amount of carbon dioxide generated by the burning of fossil fuels, households are encouraged to reduce energy consumption by insulating their homes, flooring lofts or switching lights off, etc. Studies have shown that the amount of energy being used by households has fallen significantly, showing these measures have been effective. (1 mark) Studies by the government have shown that greenhouse gas emissions have fallen by a fifth over the last 20 years, therefore local and national policies to encourage the use of environmentally-friendly vehicles and to monitor emissions carefully are proving effective. (1 mark) The Kyoto Protocol outlined agreements between developed countries to reduce their carbon emissions by 5% between 2008 and Developing countries were also encouraged to reduce their emissions.

6 In 2012, the Doha Amendment replaced the Kyoto Protocol). (1 mark) However, on a global scale, emissions continue to rise, and methane levels are predicted to continue to rise due to emissions from landfill sites and rice fields. (1 mark) For managing the local effects of climate change: Flood defences have been built to manage the local effects of extreme weather events. The Thames Barrier has successfully protected London from flooding on numerous occasions and is predicted to provide protection from one in a thousand year flood events. (1 mark) However, a second barrier may be needed to cope with flooding beyond 2070 and advance warning systems need to be further developed to advise householders of the potential risks of flooding. (1 mark) To manage the effects of drought during periods of extended rainfall, the UK has implemented hose-pipe bans but these are unpopular and difficult to enforce. (1 mark) London has built a desalination plant, which is only intended to be used in periods of extreme drought due to the high operational costs. (1 mark)