Читать книгу Sociology - Anthony Giddens - Страница 233

The consequences of global warming will be unevenly experienced, with devastating outcomes for some regions and countries but not for all. The IPCC’s Fourth Assessment Report (2007: 50–2) suggested a range of social impacts, some of the more significant of which are listed by region below.

1 Some 75 to 250 million people across Africa will experience greater stress on water supplies, and agricultural yields may fall by as much as 50 per cent, severely compromising access to adequate levels of food, increasing levels of undernourishment. The IPCC also forecast an increase in arid land by 2080 of between 5 and 8 per cent in Africa and that rising sea levels will affect low-lying coastal areas with large populations.

2 In Central, East, South and South-East Asia, availability of freshwater is forecast to be reduced by 2050, leading to increasing problems with water security. Coastal areas are likely to be subject to flooding from rivers and from the sea. As global warming changes the hydrological cycle, floods and drought will be more common.

3 In Latin America, eastern Amazonia is likely to see tropical forests becoming savannah as soils dry out, and semi-arid vegetation will be lost. Food security will be reduced as the productivity of crops and livestock declines and more people will be at risk of undernourishment and chronic hunger. Shifting rainfall patterns will lead to uncertain water supplies for drinking water and agriculture.

4 In Australia and New Zealand, the forecast is for a loss of biodiversity in important sites, including the Great Barrier Reef. Water insecurity will increase in southern and eastern Australia and parts of New Zealand. Agricultural production will decline in much of southern and eastern Australia and eastern New Zealand because of increasing droughts and fires.

5 In Europe, more frequent coastal flooding and erosion are expected as a result of sea level rise and more severe storms. Southern Europe will see more drought and higher temperatures that will reduce the availability of water and crop productivity. Higher temperatures will worsen health problems arising from more frequent heatwaves.

6 North America will experience more intense and frequent heatwaves in cities that already have problems, bringing increasing health problems. Warming in the western mountains is likely to cause more flooding in winter and reduced flows in the summer months.

7 Rising sea levels are likely to present major challenges for many small island communities in the Pacific and Caribbean. Storm surges will be higher and erosion exacerbated, threatening communities and infrastructure. By the mid-twenty-first century, water resources are likely to be reduced to the point that they will not be sufficient to meet demand during times of low rainfall.

Figure 5.1 Global and regional temperature changes: observed, natural forcing, and natural plus anthropogenic forcing

Note: All time-series are decadal averages plotted at the centre of the decade.

Source: IPCC (2015: 49).

The IPCC’s 2018 Special Report compared the impact of global warming of 1.5°C with that of 2°C above pre-industrial levels, noting that human activity has already produced warming of between 0.8°C and 1.2°C, i.e., approximately 1°C. On present trends, at 0.2°C per decade, based on previous and current emissions, 1.5°C of warming will be reached sometime between 2030 and 2052 (IPCC 2019: 6). Even if all emissions stopped immediately, warming would continue on account of past greenhouse gas emissions, but this would not reach the 1.5°C threshold.

As in the Fifth Assessment (2015), the IPCC argued that the most damaging effects of global warming could be averted if the temperature rise can be kept as close to 1.5°C as possible. All of the potentially deleterious effects of rising temperatures listed above would be worse and more difficult to reverse if 2°C is reached. To prevent that happening would require a much more systematic, wide-ranging global programme to reduce emissions alongside adaptive measures. In particular, global net emissions of CO₂ would have to be reduced to ‘near zero’ by 2050. The report acknowledges that achieving this goal will require ‘rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings) and industrial systems’ that are ‘unprecedented in terms of scale, but not necessarily in terms of speed’ (IPCC 2019: 17).

Net zero has become the slogan of XR and other environmental groups as they try to push governments to go faster in reducing carbon emissions, and much progress has been made in numerous countries to shift to renewable forms of energy and to move away from fossil-fuel-based transport systems. Yet, despite this, the scale of the task ahead is highlighted by reports that, after levelling off between 2014 and 2016, global CO₂ emissions began to rise again, by 1.6 per cent in 2017 and 2.7 per cent in 2018, ending the year at an all-time high. These rises have been attributed to oil and gas use continuing in many countries, the increasing use of coal in China (by 4.5 per cent) and India (by 7.1 per cent) (countries with very large populations), and US emissions rising by around 2.5 per cent (Figueres et al. 2018). What we can see from this brief sketch is that, without concerted global action involving all of the major polluting nations, global net zero CO₂ by 2050 will not be achieved.

The negative impact of global warming will be distributed unevenly, with already disadvantaged people and communities around the world bearing the brunt of environmental change. As we will see later, this is one reason why campaigners argue for ‘sustainable development’, which foregrounds tackling global inequality as the key to reducing emissions.