National Revision- Global Issues- Climate Change

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1 National Revision- Global Issues- Climate Change Our planet is encased in a blanket of gases, held in place by the force of gravity. This mixture gives us our life and makes our planet unique and distinctive. There is great interest about our atmosphere in the media today; global warming, ozone layer depletion, acid rain, greenhouse effect and climate change. o o The diagram above shows variations in global temperature over the past 100 years. Note that the y-axis shows the difference in degrees Celsius from the 1900 mean (average) temperature. Remember that the gradient of this line graph shows how quickly or slowly the temperature is changing - the steeper the slope, the faster the change. o You may be asked to describe what a line graph like this shows. You should begin with an overall statement ie this graph shows that the overall trend is a rise in global surface temperature from 1900 to (1) Then go into more detail: there was a drop in mean (average) temperature of 0.1 degree in the first 10 years of the 20th century (1) the temperature then increased, reaching 0.3 degrees above the 1900 mean by 1940 (1) The average temperature then dropped back to 0.2 degrees above the 1900 figure by 1950 and fluctuated around that figure until 1975 (1) in the past 25 years of the century the temperature rose rapidly to 0.7 degrees higher than 1900 by the year 2000 (1).

2 The Causes of Global Climatic Change Physical Causes o Variations in solar energy like sunspot activity raises global temperature o Volcanic eruptions - large quantities of volcanic dust in the atmosphere shield the earth from incoming insolation, lowering global temperature. For example, the eruption of Mount Pinatubo in 1991 caused a dip in global temperatures in the early 1990s. o Melting permafrost releases large quantities of methane gas. o Gases given off by rotting vegetation in Tundra areas are resulting in a reduction in the albedo effect due to more exposed land. Human Causes o The release of carbon dioxide into the atmosphere from burning fossil fuels (coal, oil and gas) o Emissions from cars and power stations releases Nitrous oxides into the atmosphere, o Deforestation means that not only does carbon absorption cease, but also the carbon stored in the trees is released into the atmosphere as CO2 if the wood is burned. o CFCs from aerosols, air conditioning systems, refrigerators etc. o Methane from rice paddies, animal dung, belching cows (one releases an average of 100kg of methane each year) and flatulent termites adds to the over 200 times more methane in the atmosphere than CO2. o Nitrous Oxides, which has one of the longest lifetimes of all the greenhouse gases, released from vehicles exhausts, power stations and fertilisers. o Landfill sites are huge areas of land that have been dug out so that domestic and industrial waste can be buried. As the waste begins to decompose it produces methane, which goes into the atmosphere. Most of these gases are thickening the blanket of greenhouse gases therefore trapping more heat. The Effects of Climate Change Positive Effects o Crops in Northern Europe and Northern Asia may grow better due to a wetter and warmer climate and result in longer growing seasons in areas like New Zealand meaning an increase in food production. o Increased tourism in colder areas like Canada due to it being warmer. o Arctic and Antarctic will experience milder climates allowing human habitation and more species to grow.

3 o Few deaths and injuries caused by cold weather in countries like Northern Russia. o Reduce in energy demands in colder countries as the temperature will be higher. o Less sea ice will result in increased sea transportation as it will be more efficient and easier to do. Negative Effects o Sea levels to rise due to the melting of the polar ice caps meaning low lying coastal areas could flood e.g. the Nile Delta and the Ganges Delta in India and Bangladesh. o Melting of ice on land areas or shorter periods of snow cover which may result in changes to habitats and plant species (Highlands of Scotland). This could result in Ski resorts having to close due to the reduction in snow o Wildlife may be lost due to changing temperature for example in the Great Barrier Reef. o Droughts will become more frequent in Central Europe as it may experience less rainfall in summer and also more heat waves. o Tropical storms will become more intense and frequent. o Agriculture in Southern Europe, the Mediterranean and North Africa are likely to experience falls in production due to a drier climate leading to famine. o Areas like the Amazon could be turned to desert which will lead to loss of wildlife and species of plants may become extinct causing problem with regards to cures for diseases which rely on these plants.

4 Strategies to Control the Effects of Climate Change Local Level o Reduce, reuse and recycle: Recycling everyday items like milk containers and paper as well as composting unused/wasted food reduces the amount sent to landfill sites and therefore reduces emissions. o Insulate your home: This will result in a less need for the use of central heating which means less fossil fuels being burnt. o Use less hot water, Use energy efficient light bulbs, Turn electrical equipment/lights off National Level UK Government Policies o The 2050 Challenge - the UK is committed to reducing greenhouse gas emissions by 80% by using more green energy. o Carbon Budgets This is a restriction on the total amount of greenhouse gases the UK can emit over five years. o Green Deal Help for businesses and householders to pay for some or all the cost of energy saving improvement to their properties. o CRC Energy Efficiency Scheme this aims to cut gas emissions in large organisations by requiring them to buy allowances for every tonne of carbon they emit. o Encourage the use of ultra low emission vehicles the government provides grants to those who purchase electric, plug in hybrid and hydrogen-powered cars and vans. It also provides funding to the Plugged-in Places programme. o Energy Bill this outlines the UK s commitment to increasing the supply of renewable energy and aims to triple the use of renewable electricity by o Tax on gas guzzlers cars that emit very low levels of carbon dioxide will pay no road tax; the more carbon dioxide cars emit, the greater the road taxed levied on them. International Level o United Nations Framework Convention on Climate Change (UNFCCC) This organisation came up with the Kyoto Protocol in The treaty sets out binding agreements between some of the most developed nations to reduce greenhouse gas emissions. Each country that signed the protocol agreed their own specific target but, combined, they committed to cut their emissions by 5% between 2008 and Developing countries do not have binding targets but are expected to reduce their emissions. In 2012 the Doha Amendment replaced the Kyoto Protocol. o European Union Legislation

5 The EU has committed to cutting its emissions by 20% by There are a number of EU initiatives to reduce greenhouse gas emissions, including the European Climate Change Programme (ECCP) and the EU Emissions Trading System. They agreed that by 2020 at least 20% of all the energy used in the EU would be from renewable energy sources. They also made targets to reduce carbon dioxide emissions from new cars and vans, and to support carbon capture and storage technologies.