2.2.4 Identifying the carbon heavyweights I've focused on two studies of the carbon footprint of UK individuals and households, but there are many others (e.g. WWF, 2006; Goodall, 2007 and Marshall, 2007a). References 2.6.2 The role of modelling studies State-of-the-art models are designed to simulate the workings of the climate system (in so far as this is currently understood), and include the ‘internal’ interactions that generate short-term natural variability in the real world. They provide modellers with a means of carrying out ‘virtual’ experiments on the climate system. In the present context, an important aim of these experiments is to identify the ‘signal’ of a human influence on climate, so studies typically involve ‘ 2.5 A ‘collective picture of a warming world’ The observed increase in GMST may be the key global indicator of greenhouse warming, but it is far from being the only tangible sign of climate change during the 20th century. This brings us back to the first bullet point at the beginning of Section 2.1. Here, we take a brief look at the growing body of evidence that many different climate variables, as well as physical and biological systems around the world, have been affected by recent climate warming. The examples collected in Box 9 will 2.2.1 Long-term rhythms in the climate The instrumental record referred to above is based on direct temperature measurements (using thermometers), and extends back only 150 years or so. Temperatures further back in time are reconstructed from a variety of proxy data. These include historical documents, together with natural archives of climate-sensitive phenomena, such as the growth or retreat of glaciers, tree rings, corals, sediments and ice cores (see Author(s): 1.7 Summary Figure 12 summarises the ways in which the Earth's surface and atmosphere gain and lose energy. The main points are as follows:  A proportion (the planetary albedo) of the incoming shortwave radiation from the Sun is reflected (or scattered) directly back to space, mainly by clouds and the Earth's surface (especially snow and ice cover), but also by aerosols (e.g. dust, salt particles, etc.). Most of the re 1.4 An overview of the global energy budget Figure 12 incorporates the additional factors considered in Section 1.3, including the non-radiative energy transfers across the surface-air boundary (green arrow). Essentially a more detailed version of Figure 7, this figure gives quantified estimates of the globally averaged energy budget for the whole Earth-atmosphere system, and its component parts. Question 3 should help you to find your way around Figure 12, and to draw together many of the key points developed so far in this chapter. M 1.1 Introduction At the beginning of the 21st century, terms such as the ‘greenhouse effect’, ‘greenhouse gases’ and ‘greenhouse warming’ are printed or spoken thousands of times a week in the context of climate change caused by human activities. This section is designed to consolidate your understanding of the basic science behind these terms, and then to review what is known about the human impact on the composition of the atmosphere since the dawn of the industrial age, commonly put (in this co 1.3.7 Corporate connections continued One issue that might be added by a workers' organisation or trade union, for instance, might be that of freedom of association and the right of workers to organise. Another might be the right to collective bargaining. In fact, the coverage of the codes of conduct vary considerably depending on who instigated the code and the parties involved (Pearson and Seyfang, 2001). Most codes of conduct, it seems, are top-down affairs, drawn up by the companies involved or by trade associations. Some hav 1.1.3 Introduction continued The difficulty perhaps is that things which happen at some distance from the everyday routine of our lives are often hard to place or connect with. Moreover, it has to be said that not everyone views factory sweatshops in quite the same way as groups such as Oxfam, or indeed endorses their negative claims about the use of cheap labour in places such as East Asia. For that is what the statements of such groups are: claims. And they are far from uncontroversial. In fact, it is poss 1.1.2 Activity 1 You have already glanced at Figure 1 and some of the worki Acknowledgements The content acknowledged below is Proprietary (see terms and conditions) and is used under licence. Grateful acknowledgement is made to the following sources for permission to reproduce material within this unit. Box 4: Four Scenarios for 2050, Royal Commission on Environmental Pollution, 22nd
Report, Energy– The Changing Climate, June 2000. Crown copyright material is reproduced under class licence number C01W0000065 with the p 4.5 Sustainability of renewable energy sources Renewable energy sources are generally sustainable in the sense that they cannot ‘run out’ – although, as noted above, both biomass and geothermal energy need wise management if they are to be used sustainably. For all of the other renewables, almost any realistic rate of exploitation by humans would be unlikely to approach their rate of replenishment by nature, though of course the use of all renewables is subject to various practical constraints. Renewable energies are also rela References 2.3.1 Public participation and perspectives on sustainability When it comes to issues around the environment, ‘experts’ – whether ecologists, economists or other types of social scientist – are clearly not infallible. Environmental crises have led to a questioning of traditional expert support as a guarantor of environmental planning. This has had two consequences. Firstly, there have been some interesting and useful explorations amongst environmentalists in seeking guarantors through the domain of spiritualism. In particular, traditional worldv 2.2.3 Ecological economics Ecological economics, which formally came to prominence in the mid-1980s, represents a departure from reliance on the use of mainstream economic modelling. Instead, it branches out to actively engage with and incorporate the ethical, social and behavioural dimensions of environmental issues. In short, ecological economics attempts to provide an interdisciplinary approach to environmental issues, whereas environmental economics maintains the primacy of economic modelling. Mark Sag 2.2.2 Environmental economics and green consumerism In economic terms, green consumerism is typically expressed using measures based on the willingness to pay (WTP) principle. As mentioned above, this takes two main forms: eco-taxation, in which environmental costs are estimated and added to the price of commodities (e.g. vehicles with high carbon emissions); and eco-labelling, in which products are labelled with relevant environmental information, such as is now required by the food industry and governments in many industrialised count 2.2.1 Environmental economics Environmental economics emerged as a sub-discipline in the 1960s, following a tradition that began in the early twentieth century with ‘agricultural’ economics and continued in the 1950s with ‘resource’ economics. In each case, natural resources are treated as environmental assets in the same way as other resource inputs, using the classical mainstream supply and demand economic models. David Pearce, who at one stage was at the forefront of environmental economics and was an ac 2.2 Economic valuation: towards ecological economics The blue whale could have supplied indefinitely a sustainable yield of 6000 individuals a year. This is one of the earliest references to sustainability in the literature, taken from the 1971 edition of the science journal Nature (cited in Senge et al., 2006, p. 45). Here, the blue whale is given instrumental value – a means of measuring not the survival of the blue whale for its intrinsic v 2.1 Accounting for the consequences of environmental harm The ethical tradition of consequentialism informs not only what matters from the perspective of caring for the environment, but also what matters from the perspective of accountability towards it. In eighteenth-century Europe, the actual environmental consequences of rapid economic development, triggered by the industrial revolutions taking place at that time, prompted an increasing concern for accountability. The most evident expression of this came with ideas of sustainable development
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