Climate Change

The Earth has a natural temperature control system. Certain atmospheric gases are critical to this system and are known as greenhouse gases. On average, about one third of the solar radiation (sunlight and heat) that arrives on earth is reflected back to space. Of the remainder, some is absorbed by the atmosphere, but most is absorbed by the land and oceans. The Earth's surface becomes warm and as a result emits infrared radiation. The greenhouse gases trap the infrared radiation, thus warming the atmosphere. Naturally occurring greenhouse gases include water vapour, carbon dioxide, ozone, methane and nitrous oxide, and together create a natural greenhouse effect.

Why Are Atmospheric Levels Increasing?

The concentrations of greenhouse gases in the atmosphere are rising as a result of human activity since the industrial revolution. Over the past 20 years, about three-quarters of human-made carbon dioxide emissions were generated through the burning of fossil fuels such as coal, oil and natural gas. An additional 20% of carbon dioxide emissions were generated by the chemical industries and agriculture (inclusive of changes in land use and deforestation).

Country emissions are very different; with wealthy people responsible for far more pollution than the poor [thus countries like the USA have far higher per capita emissions – national rate of emissions per person. The industrialised countries are responsible for emitting most of the greenhouse gasses currently in the atmosphere [where e.g. CO2 stays for about 100 years]. This historical responsibility is sometimes referred to as the ‘ecological debt’ that countries of the industrialised ‘North’ owe to those in the developing ‘South’.

Emissions have however been increasing in a number of developing countries and of these, South Africa is one of the biggest per capita emitters [accounting for between 1 and 1.5 % of total global emissions]. This is mostly because about 92% of our electricity is generated by burning coal, our liquid fuels come from coal as well as oil and the majority of our industry is energy intensive and inefficient.

Effects of Climate Change

Agriculture is adapted to seasonal rainfall. Thus shifts in rainfall pattern, as well as reduced rainfall in semi-arid areas, will significantly reduce food security. In addition, sea level rise will reduce the amount of available farming land. Production of biofuels, to displace petroleum products is also likely to reduce food availability and raises prices.

Reduced freshwater availability - lakes and reservoirs respond to climate variability with increased periods of shortage. This is likely to result in increased competition for water and migration of local populations.

A warmer climate is expected to result in an expansion in the range of carriers of vector-borne diseases such as malaria, yellow fever, and dengue fever. In South Africa, malaria risk areas are projected to expand in a southerly direction. This is likely to result in higher mortality rates among people suffering from malnutrition.

Coastal marine fisheries on the West Coast are likely to be negatively impacted by changes in the Benguela current flow.

In addition,rises in sea level, are expected to impact low-lying coastal areas such as the Cape Flats in the Western Cape.

Loss and displacements of Biomes. In South Africa, the Karoo Succulent Biome is likely to be both displaced and lose a large number of species.In South Africa, biome shifts will favour horticulture over plantation forestry.

What can you do to reduce your carbon emissions?

Use less electricity – switch off after use
Install a solar water heater (it can reduce your electricity bill by a third)
Make your home more energy efficient: use efficient light bulbs (Compact Flourescents); ensure that ceilings, geysers and pipes are well insulated.
Reduce water use e.g. repair leaks, reuse your washing water for the garden.
Reuse or recycle waste
Never burn rubbish
Support organic farming
Find out what your local government / school are doing about Climate Change; encourage them by writing letters.

For more information about climate change:

SACAN Pamphlet

Climate Change Flyer

Carbon Trading Info