Fossil fuels such as oil, gas, coal and peat are not only a finite resource, but their consumption also carries severe environmental, social and health costs. The best-known problem associated with burning fossil fuels is climate change, but several other serious environmental problems are caused by the practice, some of which we have been experiencing for decades.
The burning of fossil fuels is the primary source of extra greenhouse gases. These gases help to trap heat from the sun, keeping the earth warm; the "greenhouse effect" is, in fact, a perfectly natural and beneficial phenomenon. The problems arise when extra greenhouse gases are added to the atmosphere, trapping more heat, and triggering several vicious cycles. The results of climate change include changes in wind and current patterns, leading to more droughts, more floods, hotter temperatures in some places and, ironically, colder temperatures in others.
One of the major greenhouse gases, carbon dioxide, is partially absorbed by the oceans. The problem is that this lowers the pH of the water. In other words, it makes it more acidic. This causes problems for organisms with carbonate shells, including corals, shellfish and many species of plankton. The change in water chemistry would also impact other organisms, which, as any reef tank owner knows, are often extremely sensitive. The results might be unseen but are potentially extremely dangerous, with the entire ecosystem of the oceans changing radically.
Much more visible to humans than ocean acidification is the problem of air pollution. The burning of fossil fuels releases pollutants, including carbon monoxide, sulphur oxides, particulates, ozone and nitrogen oxides. Air pollution, or smog, causes health problems in cities including pneumonia, bronchitis and the exacerbation of existing heart and lung problems. The very young and the elderly are especially vulnerable. Air pollution is also the cause of acid rain, which can kill vegetation and pollutes water bodies sufficiently to kill off fish stocks.
Fossil fuels are not easily accessible. Some of the greatest deposits exist under the deep seas, in delicate Arctic habitats and underneath the rainforest. One of the most recent fossil fuels to be commercially exploited, tar sands, occurs within the forests and wetlands of North America. Extracting fossil fuels inevitably causes habitat destruction and loss of biodiversity. Mining and drilling operations often result in pollution in their own right.