Indicator: A-41 Greenhouse - climate change projections

Data

Ranges of average annual warming(°C) for around 2030 and 2070 relative to 1990

Ranges of average annual warming(deg;C) for around 2030 and 2070 relative to 1990

Source: CSIRO Atmospheric Research 2001, Climate Change Projections for Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/projections2pp.pdf

Range of annual average rainfall change(%) for around 2030 and 2070 relative to1990

Source: CSIRO Atmospheric Research 2001, Climate Change Projections for Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/projections2pp.pdf

Table 1: Climate Change Projections for annual average maximum temperature ¹
	Now	2030	2070
Alice Spring	28.6	29.8 ± 0.8	32.1 ± 2.5
Adelaide	21.4	22.4 ± 0.7	24.4 ± 2.2
Brisbane	25.5	26.5 ± 0.7	28.5 ± 2.2
Broome	32.2	33.4 ± 0.8	35.7 ± 2.5
Cairns	28.9	29.9 ± 0.7	31.9 ± 2.2
Darwin	31.9	33.1 ± 0.8	35.4 ± 2.5
Melbourne	19.8	20.8 ± 0.7	22.8 ± 2.2
Perth	23.3	24.3 ± 0.7	26.3 ± 2.2
Sydney	22.1	23.3 ± 0.8	25.6 ± 2.5

¹ The quoted uncertainties represent the full range obtained from nine different climate models and forty emissions scenarios.

Source: CSIRO and AGO 2002, Future Climate Change in Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/cechet_2002a.pdf

Table 2: Climate change projections for Dec-Feb days above 35°C
	Now	2030	2070
Alice Spring	55	63 ± 5	73 ± 11
Adelaide	10	13.5 ± 2.5	21 ± 7
Brisbane	2.5	4.5 ± 1.5	20 ± 15
Broome	17	36 ± 17	57 ± 30
Cairns	3	5.5 ± 2.5	41 ± 35
Darwin	1	7.5 ± 5.5	42 ± 37
Melbourne	8	10.5 ± 1.5	15 ± 5
Perth	15	19 ± 3	29 ± 10
Sydney	2	3 ± 1	7 ± 4

Source: CSIRO and AGO 2002, Future Climate Change in Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/cechet_2002a.pdf

Table 3: Climate change projections for annual rainfall (mm)
	Now	2030	2070
Alice Spring	285	295 ± 20	315 ± 65
Adelaide	454	435 ± 35	400 ± 110
Brisbane	1146	1100 ± 90	1010 ± 275
Broome	596	570 ± 95	525 ± 285
Cairns	2028	1945 ± 160	1785 ± 485
Darwin	1710	1710 ± 70	1710 ± 205
Melbourne	657	630 ± 50	580 ± 155
Perth	869	800 ± 105	660 ± 310
Sydney	1102	1070 ± 70	970 ± 265

Source: CSIRO and AGO 2002, Future Climate Change in Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/cechet_2002a.pdf

Source: CSIRO Atmospheric Research 2001, Climate Change Projections for Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/projections2pp.pdf

climate Change - Projections for Australia (PDF - 1740 KB)

Figure 1 shows simulated ranges of warming for Australia. By 2030, annual average temperatures are 0.4 to 2.0°C higher over most of Australia, with slightly less warming in some coastal areas and Tasmania, and the potential for greater warming in the north-west.

By 2070, annual average temperatures are increased by 1.0 to 6.0°C over most of Australia with spatial variation similar to those for 2030. The range of warming is greatest in spring and least in winter. In the north-west, the greatest potential warming occurs in summer.

Model results indicate that future increases in daily maximum and minimum temperature will be similar to the changes in average temperature. This contrasts with the greater increase in minima than maxima observed over Australia in the 20th century.

Changes in daily temperature extremes can be influenced by changes in daily variability and changes in average maximum or minimum temperature. CSIRO modelling results for Australia indicate that future changes in variability are relatively small and the increases in average maximum and minimum temperature mainly determine the change in extremes.

Figure 2 shows changes in annual average rainfall for around 2030 and 2070, relative to 1990. Changes tend toward a decrease in the south-west (-20% to +5% by 2030 and -60% to +10% by 2070), and in parts of the south-east and Queensland (-10% to +5% by 2030 and -35% to +10% by 2070). Most other locations show changes that vary from -10% to +10% by 2030 and -35% to +35% by 2070.

Source: CSIRO Atmospheric Research 2001, Climate Change Projections for Australia, viewed 22 Mar 2006, http://www.cmar.csiro.au/e-print/open/projections2pp.pdf.

Tables 1, 2 and 3 show projections for temperatures and rainfall for various Australian cities for 2030 and 2070 estimated by CSIRO and the Australian Greenhouse Office. They have projected that temperatures will increase by around 1 degree by 2030 (± 0.8) and by between 3 and 3.5 degrees by 2070 (± 2.5). In terms of rainfall, most locations show a 4% decrease in rainfall by 2030 and a 12% decrease by 2070.

Data Limitations

The projections are based on results from computer models that involve simplifications of real physical processes that are not fully understood. The data represents scenarios based on assumptions. Different assumptions may produce different results.

Issues for which this is an indicator and why

Atmosphere — Climate variability and change - Greenhouse

Greenhouse gas emissions and atmospheric concentrations are measurable, and provide insight into the potential for climate change. Weather phenomena are also measurable but may be indicative of either climate change or of natural fluctuations. Neither provides useful insight into what we may expect in terms of long-term changes of climate. Modelling of how climate might be changing and might change over the course of the next century is probably the only useful indicator for this.