The energy sector (comprising stationary energy, transport and fugitive emissions from fuels) continues to be the dominant source of Australia’s GHG emissions, accounting for 74% of net emissions, including those associated with land use, land-use change and forestry (LULUCF) (Figure 3.10). Within this sector, stationary energy accounts for 52%, comprising electricity (37%) and fuel combustion (15%).
Australia’s very high level of emissions per person reflects the nation’s heavy reliance on fossil fuels as a primary energy source and, in particular, the dominant role of coal (an emissions-intensive fuel) in the production of electricity (Figure 3.11).
Although the transport and agricultural sectors both contribute around a sixth of Australia’s net GHG emissions, transport’s contribution is almost entirely through emissions of carbon dioxide, whereas agriculture’s contribution is through methane and nitrous oxide—gases with global warming potentials many times that of carbon dioxide (Figure 3.12). (The 100-year warming potential of methane is 21 times that of carbon dioxide; the figure for nitrous oxide is 310.)41
Under Article 3.3 of the Kyoto Protocol, parties can use net changes in GHG emissions associated with direct human-induced LULUCF activities that occurred since 1990 to meet their emission reduction commitments. Australia, in meeting its obligations to account for its GHG emissions under the protocol, includes net emissions associated with LULUCF. However, these tend to vary significantly from year to year, reflecting variability in climate; peaks (such as in 2007) are associated with extreme events such as bushfires and drought, which lead to major loss of carbon from vegetative and soil sinks.