2.5.2 Environmental indicators The notion of a link between climatic conditions and the behaviour of plants and animals (e.g. the growth of trees or coral) and the composition of natural communities or ecosystems (the type of vegetation in a given area, say) is fundamental to the use of proxy data to reconstruct past climates. Some examples of biological responses to recent climate change were included in Box 9. Here we should be wary of jumping to conclusions. Such changes involve complex living systems that can respond i
2.5.1 Physical and weather-related indicators The indicators collected in Table 4 have been observed to change over large regions of the Earth during the 20th century. According to the TAR, there is now a good level of confidence that what is being recorded is the result of long-term change rather than short-term natural fluctuations. As we noted earlier (Section 2.2.2), the most recent period of warming has been almost global in extent, but particularly marked at high latitudes. So are the changes in Table 4 consistent with rising tempe
2.2.2 Temperature changes over the past millennium One of the most striking images in the IPCC TAR is reproduced (in adapted form) in Figure 24. Together, these two temperature records tell a compelling story, crystallised in our earlier quotes from the SPM. So let's just pause to take a closer look at each of them. 2.2 Records of the Earth's temperature To put the temperature records reported by the IPCC in context, we start with a longer-term geological perspective on the Earth's GMST. 1.5 ‘Radiative forcing’ as an agent of climate change Since its first major report in 1990, the IPCC has used the concept of ‘radiative forcing’ as a simple measure of the importance of a potential climate change mechanism. The basic idea is straightforward. Any factor that disturbs the radiation balance at the top of the atmosphere has the potential to ‘force’ the global climate to change: it will either warm up or cool down until a balance is restored. The perturbation to the energy balance of the whole Earth-atmosphere system i 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 1.3.4 The role of convection in the atmosphere We come now to our final refinement to the simple picture in Figure 7. Recall that the troposphere is heated from below, with temperature then falling with increasing altitude. This situation sets the scene for the onset of convection – the bulk flow or circulation of a fluid driven by differences in temperature. Convection in the atmosphere plays a vital role in two further mechanisms – quite apart from the emission of longwave radiation – whereby energy is transferred from the 1.2 A framing paradox: experiencing nature with cognitive tools Whilst language tools are helpful in conveying meaning in conversation amongst humans, establishing what matters in ‘conversation’ between human and non-human nature, or amongst non-human living entities, requires different cognitive tools. Cognition refers to the way in which external information from the environment is processed. As sentient beings, humans and some other animals are able to experience wellbeing and suffering. In the next reading, Ronald Moore examines how we engage with Learning outcomes By the end of this unit you should be able to: understand why systems thinking might be useful and know something about how it can be applied in the context of environmental responsibility; describe the significance of environmental pragmatism and cognitive justice as tools for supporting environmental policy and action. 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 References 1.1.1 Where do we get our energy from? The world’s current energy systems have been built around the many advantages of fossil fuels, and we now depend overwhelmingly upon them. Concerns that supplies will ‘run out’ in the short-to-medium term have probably been exaggerated, thanks to the continued discovery of new reserves and the application of increasingly advanced exploration technologies. Nevertheless it remains the case that fossil fuel reserves are ultimately finite. In the long term they will eventually become deplet Learning outcomes When you have completed this unit, you should: have an awareness of the current sources of energy; have an awareness of current solutions for energy sustainability problems. References 2.4.2 Ecological restoration The changing science of ecology, coupled with a greater awareness and development of alternative styles of managing natural resources, continues to influence our notion of what is good and what is right for nature. One of the first and most influential formal expressions of an environmental ethic that arose from early organic and ecosystems models of ecology was that of Aldo Leopold. Leopold’s argument is regarded as an environmental ethic because it explicitly gives moral consideration to, References 2.1 Conversing with environment Consider a situation involving what might be regarded as eco-social collapse. For example, the trigger of global warming (caused primarily by use of fossil fuels in developed countries) has encouraged the rapid development of biofuel agriculture through grants from rich countries in the global North to Brazil and other tropical countries in the global South. This has generated both ecological problems (deforestation, pesticide pollution, etc.) and socio-economic problems – particularly with 1.2 Connecting human and non-human nature Environmental responsibility – caring and generating accountability – requires interaction between human and non-human nature. For example, from a caring perspective what matters in climate change might constitute, say, the continued existence and protection of an arctic wilderness (Figure 3). But this necessarily involves a conne Introduction This unit explores different understandings of nature and environment and the significance these may have for developing responsibility. The problems of connecting human and non-human nature are presented here as being a challenge peculiar to the concerns of environmental responsibility. They provide the impetus for exploring the idea of ‘conversation’ as a metaphor for what matters in environmental responsibility. Using a reading by Stephen Talbott as a foundation, the conversation me Acknowledgements This unit was prepared by Tom Power with guidance from Dr Arlene Hunter. Tom Power is a lecturer in science education at The Open University. His research interests include teacher education in the global south (www.open.ac.uk/deep) and the CASE intervention. He has been a teacher and an advisory teacher in East Sussex and a specialist adviser to the TTA teacher research panel. Dr Arlëne Hunter, Staff Tutor in Science in Ireland
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