There could be many impacts on society and the environment as a result of these changes to the Earths atmosphere and temperature. One such effect will be that the sea level will rise. Scientists predict that it will rise by about half a metre by the end of the century. The reasons for this rise are mainly due to the thermal expansion of the oceans and the melting of glaciers. In Greenland, a temperature rise of more than 3ºC would start to melt the icecap. Although this would take many thousands of years, it alone will result in an eventual total sea level rise of about 7 metres. This rate of sea level rise over the next 100 years would not cause a significant problem to the UK, however, the Thames barrier would need modification and extensive resources would have to go into improving sea defences, especially along the low lying east coast regions. Most developed countries, such as The Netherlands, would also be able to cope. On the other hand however, the situation would be very different for the developing countries. For example in Bangladesh (see picture above) there are around 10 million people living within 1 metre of present sea level. Countries such as these would not be able to afford adequate defences against such a rise in sea level. Many low lying islands in the Indian and Pacific oceans, such as the Maldives (see picture below), are likely to become uninhabitable. A rise in sea levels could result in salinization of ground water.
A second major impact is on precipitation and water supplies. Heavy rainfall will get heavier, and light rainfall will often get lighter. This is because in a warmer world more water is evaporated from the surface, more water vapour enters the atmosphere and more water vapour condenses to form clouds. This will therefore result in the hydrological cycle becoming more intense. There has also been a noticeable change in El Nino. This natural phenomenon has been returning far more frequently.
Agriculture will be affected by the increase in carbon dioxide. This has a fertilising effect on crops. The climate changes will also effect growth and yield. They could be aided by these changes, although plants may also be harmed due to heat stress. The increase in temperature will also mean a decrease in soil moisture, which is one of the main factors in the cause of soil erosion and eventually desertification. There will also be an effect on human health. There will be a higher death rate in the developed countries as the extreme temperatures ranges will cause more heart disease and strokes. Increases in mortality have been noted in London during spells of hot weather (Haines, 1991), however in Europe more deaths occur in extreme weather than in hot weather (Kovats et al 1999). Air pollution is also linked to warmer summers so this will therefore increase with global warming. Air pollution affects people with respiratory problems such as asthma. Other diseases such as malaria and typhus, which were previously extinct from Europe, may become prominent. As the climate becomes more temperate, the animals or plants which carry the virus will distribute into other areas and therefore spread the disease.
To reduce this effect there are two options: mitigation and adaptation. Mitigation is where we seek to find ways in which to reduce greenhouse gases and implement these strategies. We can be energy efficient by using products that require less energy to run and we could also conserve energy by switching off energy consuming items when they are not required. Transport is a major factor in producing carbon dioxide and there are many ways this problem can be handled such as using public transport or by using light weight cars. We could also research different methods of energy production as a substitute for fossil fuels. There is nuclear power but this also has its problems as accidents such as Chernobyl have shown this. Reforestation would also be an effective way of reducing carbon dioxide levels. Adaptation will be made much easier when put into practice with mitigation, as this will result in less adaptation being needed. This is where we try to allow societies and ecosystems to cope better with the inevitable effects of climate change. However, it does not benefit a single nation to take action unless others will act alongside it. Therefore the Kyoto Protocol was produced in 1997. It is the first agreement under the FCCC with greenhouse gas emission reduction targets that will be binding in international law. The FCCC itself set voluntary targets for industrialized nations such that their CO2 emissions should be no higher in 2000 than they were in 1990. Developing countries argued that they had no responsibilities to cut emissions because the industrialized countries were the main emitters of greenhouse gases. As it happens, not many nations will meet their voluntary targets. The Kyoto Protocol sought a 5.2 per cent reduction in overall greenhouse gas emissions by about 2010 relative to 1990. This target applies collectively to industrialized economies only. Once again, developing countries have no mandatory targets. The target is differentiated between industrialized countries. The European Union as a whole must achieve an 8 per cent reduction, the United States 7 per cent, and Japan 6 per cent.
Global warming requires action soon. Conditions are shifting rapidly, meteorologically and otherwise. Most of the public is now intuitively aware of climate change--and extremely worried about changes in the weather. Growing numbers of corporate leaders are realizing that the remedy--a world-wide transition to renewable and high-efficiency energy sources--would, in fact, create a huge surge of jobs and a dramatic expansion in the total wealth of the global economy. And national as well as grassroots political activists are at last making the climate crisis the focus of campaigns. It is too slow and too small--but it is a beginning. The issue is not whether we will mobilize around the climate crisis, but whether we will do it in time.
Bibliography
Drake, F. 2000: Global Warming, The Science of Climate Change. London: Oxford University Press
Haines, A. 1991: Global Warming and Health. British Medical Journal
Houghton, J.T 2000: Global Warming. Cambridge: Cambridge University Press
Houghton, J.T Meira Filho, L.G., Callander, B.A., Harris, N., Kattenburg, A. and Maskell, K. 1996: Climate Change. Cambridge: Cambridge University Press
Kovats, R.S., Haines, A., Stanwell-Smith, R., Martens, P., Menne, B. and Bertollini, R. 1999: Climate Change and Human Health in Europe. British Medical Journal
