Australia's net greenhouse gas emissions have risen by over 17% between 1990 and 1999. Per capita, we have one of the world's highest levels of greenhouse gas emissions. (SEE FOOTNOTE 2) Our heavy reliance on fossil fuel burning for energy rather than other forms of power (such as nuclear) and the strucutre of our economy are two influences behind our high rate of emissions.

The main gases in the Earth's atmosphere, nitrogen and oxygen, are almost completely transparent to the sun's rays. But water vapour, carbon dioxide and other gases form a blanket around the Earth, trapping heat. This process is known as the greenhouse effect. Human activity is increasing atmospheric concentrations of existing greenhouse gases (such as carbon dioxide and methane) and adding new gases such as chlorofluorocarbons (CFCs). A number of experts believe that these gases are linked to global warming and climate change by way of an enhanced greenhouse effect. (SEE FOOTNOTE 3)

Ideally, the headline indicator would assess Australia's total greenhouse emissions. But it is difficult to measure emissions from some sources accurately, especially emissions from land clearing and agriculture. The headline indicator graph looks at Australia's net emissions (excluding those from land clearing). Estimated total emissions (including land clearing) are also shown in the graph, but only as background information.

Australia's net greenhouse emissions in 1999 were about 460 megatonnes (Mt) CO₂-e, up from around 390 Mt CO₂-e in 1990, an increase of 17.4%. Our total emissions stood at almost 530 Mt CO₂-e in 1999, an increase of 7.4% over the period.

In order to compare countries of different population size, one can consider per capita emissions of greenhouse gases; about 24 tonnes of CO₂-e, were produced for every Australian in 1999. These figures are high by international standards. Our per capita emissions of CO₂ (the main greenhouse gas) from fossil fuel burning, for instance, are among the highest in the world (in 1997 our emissions were some 30% higher than the Organisation for Economic Co-operation and Development (OECD) average). (SEE FOOTNOTE 4)

Australia's relatively heavy use of both coal-fired power stations and road transport are two important factors contributing to the high per capita emissions.

Climate change is predicted to impact upon different parts of Australia in different ways. Data beginning in 1910 show that annual mean temperatures in Australia have increased; (SEE FOOTNOTE 10) while the World Meteorological Organization reports that temperatures in the 1990s were the warmest since records began in the 1860s.

NET AND TOTAL EMISSIONS Greenhouse gases are emitted by human activity such as the burning of fossil fuels, but are also absorbed in carbon sinks (growing vegetation absorbs CO2 during photosynthesis, while carbon is absorbed into soil by farming practices such as pasture improvement). The headline indicator considers net emissions, which comprise the greenhouse gases released from activities like the burning of fossil fuels, less those absorbed by forests, etc. But significant amounts of greenhouse gases arise from land clearing, and are excluded from the net emissions figure because only rough estimates are available at the moment. When land is cleared, greenhouse gases - mainly CO2 - are released from the burning and decay of vegetation or from the disturbance of soil which releases carbon. The sum of net emissions and those from land clearing are referred to above as total emissions. GLOBAL WARMING AND CLIMATE CHANGE Over the past 100 years, global mean surface temperatures have increased by 0.4 to 0.8 0 C, and the World Meteorological Organization reports that the 10 warmest years in the past 140 have all occurred since 1983. (SEE FOOTNOTE 5) Some of this change may be natural, but over the past 200 years human activity has altered the world's atmosphere; (SEE FOOTNOTE 6) and there is increasing evidence that these atmospheric changes are having an influence on the climate through the enhanced greenhouse effect. The effects of global warming are very difficult to predict but are of global concern. CSIRO predicts that, relative to 1990, average annual temperature in Australia may increase by 0.4 to 2 0 C by 2030 and by 1 to 6 0 C by 2070. (SEE FOOTNOTE 6) Global warming may cause regional rain patterns to change (both within Australia and around the world), while melting glaciers and the thermal expansions of seawater may raise global sea levels by between 15 and 95 cm by the year 2100 (with a current 'best estimate' of 50 cm). (SEE FOOTNOTE 7) CLIMATE CHANGE AND BIODIVERSITY The possible effects of climate change on Australian wildlife are yet to be fully documented, but several species are believed to be threatened, including the endangered Mountain Pygmy Possum which could, scientists predict, lose its entire alpine habitat with just a 1 0 C rise in mean annual temperature. (SEE FOOTNOTE 8) It also appears that many corals in the Great Barrier Reef are living close to their survival limits in terms of sea temperature. (SEE FOOTNOTE 9)

FACTORS INFLUENCING CHANGE

The size of the economy, its structure and the energy intensity of industries are important determinants of emissions. In 1999 the energy sector (mainly power stations and transport) accounted for almost 80% of net emissions, with electricity generation - primarily from coal-fired power stations - accounting for half the sector's emissions. More than half of this sector's greenhouse gases were emitted as a consequence of the production and/or consumption of goods and services used by households (particularly domestic electricity and motor vehicle fuel), and about a quarter of emissions were generated in the production of goods and services for export. (SEE FOOTNOTE 11) The energy sector's emissions grew more quickly than those of any other sector (22% between 1990 and 1999).



Agriculture was the second largest emitter, and accounted for over a fifth of net emissions in 1999 (mainly methane from livestock).

Forestry was a net consumer of CO₂ throughout the period, because growing trees absorbed more CO₂ than was released from trees felled. In 1999 the net carbon sink from the forestry sector was about 26 Mt CO₂-e, about 5% less than in 1990.

Other things being equal, growth in industries that are emissions-intensive (such as iron, steel and aluminum smelting) will increase greenhouse gas output more than growth in sectors such as service industries which are less energy- and emissions- intensive. The price of energy also has an influence in managing demand. Electricity prices fell in Australia during recent years, while the relatively low cost of vehicle fuel here helps to explain why our cars are larger, less fuel efficient and driven more than in many other countries. (SEE FOOTNOTE 12)

The net emissions figures do not take into account the added effects of land clearing, mainly for agriculture, which was estimated to generate a further 71.7 Mt CO₂-e in 1999 (increasing net emissions by over 15%). This was about two-thirds of the estimated emissions from land clearing in 1990, but higher than any of the levels between 1991 and 1998.

Reducing greenhouse gas emissions has become the subject of major international negotiations. In 1992, Australia ratified the United Nations Framework Convention on Climate Change, which sought to stabilise greenhouse gas concentrations in the atmosphere. The convention was updated by the Kyoto Protocol of 1997, which Australia signed but has not yet ratified. Under the protocol, developed countries agreed to accept greenhouse gas emission targets. Australia's target is to restrict annual average emissions over the period 2008 to 2012 to no more than 8% above their 1990 level.

Australia's relatively high rates of population and economic growth are important factors behind the growth in our emissions, and it is interesting to consider the changes in overall net emissions alongside the changes in per capita emissions and emissions per dollar of GDP. Although emissions of greenhouse gases per capita increased by 5.7% between 1990 and 1999, emissions per $ of GDP fell by almost 13%, reflecting the fact that, over the period, economic growth was faster than the growth in emissions: the economy became less emissions-intensive.

LINKS TO OTHER DIMENSIONS OF PROGRESS

Greenhouse gas emissions and climate change are more than an environmental concern. While Australia's biodiversity and freshwater ecosystems might be affected by climate change, global warming could - if the projections of the International Panel on Climate Change prove correct - have profound consequences for our economy and society (increasingly frequent and severe floods and rising sea levels, for instance, have the potential to cause significant damage).

Emissions are linked to economic activity, through the burning of fossil fuels, certain industrial processes, agriculture and forestry. However, the development and adoption of new low-emissions technology, such as wind power, might play an important role in reducing emissions in the future (see the commentary Atmosphere: Looking more closely).

See also the commentaries National income, Biodiversity, Land clearing, and Knowledge and innovation.


FOOTNOTES

1 CO₂ equivalent emissions. Different greenhouse gases have different effects and remain in the atmosphere for different periods of time. A tonne of methane, for example, contributes as much to global warming as 21 tonnes of carbon dioxide (CO₂). To assess the impact of the different gases together, emissions of each gas are converted to a common CO₂ equivalent (CO₂-e) scale and added. For example, a tonne of methane and a tonne of CO₂ would equate to 22 tonnes of greenhouse gases CO₂-e.

2 Turton, H. and Hamilton, C. 2001, Comprehensive Emissions per capita for Industrialised Countries, The Australia Institute, Canberra.

3 Intergovernmental Panel on Climate Change 2001, Summary for Policymakers of the Contribution of Working Group I to the IPCC Third Assessment Report, Cambridge University Press, Cambridge.

4 Australian Bureau of Statistics 2001, Australia's Environment: Issues and Trends, Cat. no. 4613.0, ABS, Canberra.

5 World Meteorological Organization, WMO Statement on the Status of the Global Climate in 2000, URL: http://www.wmo.ch/web/Press/Press657.html last viewed 21 February 2002.

6 Commonwealth Scientific and Industrial Research Organisation 2001, Climate Change: Impacts for Australia, Marine Research Organisation, Hobart. URL: http://www.marine.csiro.au/iawg/impacts2001.pdf last viewed 21 February 2002.

7 United Nations 2001, Climate Change. URL: http://www.un.org/cyberschoolbus/briefing/climate/climate.pdf last viewed 21 February 2002.

8 Brereton, R., Bennett, S. and Mansergh, I. 1995, "Enhanced greenhouse climate change and its potential effect on selected fauna of south-eastern Australia: a trend analysis", Biological Conservation, 72, pp. 339-354.

9 Lough, J.M. And Done T.J. 2000, "Coral bleaching collaborations at the Australian Institute of Marine Science", Climate Change Newsletter, Vol. 12(1), pp.7-8.

10 Bureau of Meteorology 2000, Australian Annual Mean Temperature Anomalies, URL: http://www.bom.gov.au/climate/change/amtemp.shtml last viewed 22 February 2002.

11 Australian Bureau of Statistics 2001, Energy and Greenhouse Gas Emission Accounts 1992-93 to 1997-98, Cat. no. 4604.0, ABS, Canberra.

12 Australia and New Zealand Minerals and Energy Council (ANZMEC) 2001, Energy Trends: an analysis of energy supply and use in the National Energy Market - 2000, ANZMEC, Canberra.

Previous Page

Next Page