Environmental Education: Part 1
– Environmental Issues
Jack Hiroki Iguchi
(Professor, Graduate School of Environmental Sciences, Aomori University, Japan)
In this series, environmental education in general and specifically through museums will be considered. In part 1, certain terms concerning environmental issues will be defined and their historical background will be examined.
Currently there are many worldwide environmental issues related to the destruction of nature. Some serious problems arose during the industrial revolution, because coal fires and factory chimneys began to pour an obnoxious mixture of smoke into the air (Carwardine M. 1990:21). After the Second World War, industrialization became more widespread and these problems became global. Scientific research into these fields has been necessary as government and also many non-governmental organisations (NGOs) have taken a role in solving these serious issues.
Environmental Issues on the Increase
One serious problem is the result of the accumulation of carbon dioxide crystals, methane, CFCs, ground-level ozone, nitrous oxide and water vapour in the upper atmosphere, which insulates the earth and raises the atmospheric temperature by preventing heat loss (Collin P.H. 1992: 101, Carwardine M. 1990: 32). Human activities change the delicate mix of gases in the atmosphere, with the result that the average global temperature has increased already by some 0.5℃ since 1850 (Carwardine M. 1990: 31). In 1860, worldwide annual emission of CO2 from industrial sources was less than 1 billion metric tons, but just after the Second World War it reached 5 billion metric tons, and it has increased 3.6 times since 1950 (The World Resources Institute 1992: 5). If this pollution goes on growing at the present rate, by 2020 the average global temperature will have increased by 1.0℃ since 1990 (Wright D. 1992: 21).
The greenhouse effect comes from a variety of human activities such as:
1. The generation of electricity: the burning of fossil fuels that give off carbon dioxide produces most of the electricity we use.
2. Cars: They have carbon dioxide and nitrogen oxide in their exhaust fumes.
3. CFCs (Chlorofluorocarbons): They are also greenhouse gases. Aerosols; foam plastic fast-food containers; padding from cushions and cars; coolants from fridges and air conditioners all contain CFCs.
4. Dumping rubbish: Household rubbish, which gets buried in landfills, and then methane is released into the air.
5. Destroying rainforests: Forests absorb millions of tons CO2 a year, so cut trees down at the same time increases the amount of CO2. To make matters worse, when forests are burned the fire releases CO2, which adds to the greenhouse effect (Bronze L. et al, 1990: 18).
Acid rain, which contains a higher level of acid (ph 4.5 to 2.5) than normal (ph 6.5), is mainly caused by sulphur dioxide, nitrogen oxide and other pollutants that are released into the atmosphere when fossil fuels containing sulphur are burned (Collin P.H. 1992: 2, Jones G. et al, 1990: 3).
The problems really started when coal fires began to pour into the air a noxious mixture of smoke and gases. In 1952, in London, for nearly a week the city was smothered in a stinking sulphurous cloud and finally it killed 4,000 people (Carwardine M. 1990: 21).
Acid rain is literally eating away at our earth, destroying woods, forests, soil, and even historic buildings. It is also polluting rivers and lakes (Bronze L. et al, 1990: 36), resulting in fewer fish – so fewer fish-eating birds survive. The most serious areas attacked by acid rain are the east coast of the USA and around Denmark. However, other areas attacked by acid rain are the eastern seaboards of the USA and Canada, nearly all of Europe, and Hong Kong. Some other developing countries could have this problem in the future such as Venezuela, around Uruguay, the countries facing the Gulf of Guinea, South Africa and the western parts of Malaysia and Indonesia (Wright F. 1992: 16).
Ozone Layer Depletion
Between 20 and 50 km above the surface of the earth, the ozone layer exists. It is created by the effect of UV (ultraviolet) radiation from the sun on oxygen. It is now being destroyed by reaction with chlorine compounds (from CFCs – chlorofluorocarbons – used in aerosols and packing). The destruction or reduction of the layer has the effect of allowing more radiation to pass through the atmosphere with harmful effects on the natural world (Collin P. 1992: 37, 155).
For example, a depletion of just 1% of the ozone layer causes a 2% increase in the incidence of skin cancers; worldwide, more than 100,000 people are already dying from UV–induced skin cancers every year; a higher dose of UV may slow down plant photosynthesis; too much UV radiation tends to disorientate plankton in the sea, causing them to die and it would effect the entire ocean ecosystem (Cowardice M. 1990: 29). On the other hand, ironically enough, ground-level ozone has increased by more than 60% in Europe and North America since the 1920s. It creates a photochemical smog that chokes cities (Ibid: 27). CFCs, which cause ozone depletion in the stratosphere, are classified by numbers: CFC-10 is used in aerosols; CFC-11 is used to make plastic foam; CFC-12 is a coolant for refrigerators; CFC-13 is a cleaning substance used in the electronics industry (Collin P. 1992: 40).
Some measurements indicate that peak ozone destruction has reached 60% over Antarctica and about 6% in the mid-latitudes (The World Resources Institute, 1992: 9). If we now stop using CFCs, the CFCs that we have already emitted into the atmosphere will reach the stratosphere in seven years time (Collin P. 1992: 40).
Destruction of Habitats and Wildlife
Habitats, the natural home of groups of plants and animals (Spurgeon R. 1988: 5) and wildlife, wild animals and birds (Collin P. 1992: 233), are now being destroyed at a threatening rate.
Disappearing tropical rainforests, which grow in areas where rainfall and temperatures are both high and constant, is a classic example. Great rainforests stretch around the equator and are the most complex ecosystems (habitat and community – the group of plants and animals) in the world, and contain a wealth of resources (Spurgeon R. 1988: 5, 26).
In the 1940s 15% of the earth's land surface was covered in tropical rainforest. However, today less than half of it is left. According to FAO (The United Nations Food and Agriculture Organisation) research, about 100,000 square kilometers of rainforests is cleared completely every year (Carwardine M. 1990: 49). Especially, most of the rainforests in Central America, the East Coast of Brazil, Central Africa and South East Asia have disappeared (Wright D. 1992: 15).
Tropical rainforests are richer in species than any other terrestrial habitats. They contain at least 50% and perhaps 90% of the world's species (The World Resources Institute, 1992: 130), and also play a vital role in regulating the world's climate through their position in the oxygen, carbon and water cycles (Spurgeon R. 1988: 27).
Hunting, poaching and the wildlife trade also are large problematic issues. The late 19th and 20th centuries have seen a wave of extinctions and population declines, perhaps unprecedented in the history of the world. International trade in wildlife is worth about US$ 5 billion a year and involves thousands of different species (Carwardine M. 1990: 86, 89).
Disappearing coral reefs is another serious issue. Coral reefs are the underwater analog of tropical forests, which have a great number of species. They are now under severe pressure from a variety of threats including over-fishing, agricultural and industrial pollution; smothering by soil erosion from upstream agricultural lands and the destruction of forests; and also global climate change (The World Resources Institute, 1992: 131).
Finally, the variety of human-related pollution destroys habitats and kills animals and plants in most parts of the world. In the next article other important issues will be addressed, and scientific research on environmental issues and support of NGOs will be examined.
Bonze L., Heathcote N. & Brown P., 1990. The Blue Peter Green Book, BBC Sainsbury's: 18, 36.
Carwardine M. 1990. The WWF Environment Handbook, WWF: 21, 27, 29, 31, 32, 49, 86, 89.
Collin P.H., 1992. Dictionary of Ecology and the Environment, Peter Collin Publishing: 2, 37, 40, 101, 155, 233.
Jones G. et al, 1990. Dictionary of Environmental Science, Collin: 3.
Spurgeon R., 1988. Ecology, Usborne: 5, 26, 27.
The World Resources Institute, 1992. World Resource 1992-93, Oxford University Press: 5, 9, 130, 131.
Wright D., 1992. Environment Atlas, WWF: 15, 16, 21.