Australian climate change impacts, adaptation and vulnerability

Full text: Full text: The IPCC Fourth Assessment Report on impacts, adaptation and vulnerability made the following conclusions about Australia (Hennessy et al., 2007): Regional climate change has occurred. Since 1950, there has been 0.70C warming, with more heat waves, fewer frosts, more rain in north-west Australia, less rain in southern and eastern Australia, an increase in the intensity of Australian droughts and a rise in sea level of about 70 mm. Australia is already experiencing impacts from recent climate change. These are now evident in increasing stresses on water supply and agriculture, changed natural ecosystems, and reduced seasonal snow cover. Some adaptation has already occurred in response to observed climate change. Examples come from sectors such as water, natural ecosystems, agriculture, horticulture and coasts. However, ongoing vulnerability to extreme events is demonstrated by substantial economic losses caused by droughts, floods, fire, tropical cyclones and hail. The climate of the 21st century is virtually certain to be warmer, with changes in extreme events. Heat waves and fires are virtually certain to increase in intensity and frequency. Floods, landslides, droughts and storm surges are very likely to become more frequent and intense, and snow and frost are very likely to become less frequent. Large areas of mainland Australia are likely to have less soil moisture. Potential impacts of climate change are likely to be substantial without further adaptation; As a result of reduced precipitation and increased evaporation, water security problems are projected to intensify by 2030 in southern and eastern Australia; Ongoing coastal development and population growth, in areas such as Cairns and south-east Queensland, are projected to exacerbate risks from sea level rise and increases in the severity and frequency of storms and coastal flooding by 2050. Significant loss of biodiversity is projected to occur by 2020 in some ecologically rich sites, including the Great Barrier Reef and Queensland Wet Tropics. Other sites at risk include Kakadu wetlands, south-west Australia and alpine areas; Risks to major infrastructure are likely to increase. By 2030, design criteria for extreme events are very likely to be exceeded more frequently. Risks include failure of floodplain protection and urban drainage/sewerage, increased storm and fire damage, and more heat waves causing more deaths and more black-outs; Production from agriculture and forestry is projected to decline by 2030 over much of southern and eastern Australia, due to increased drought and fire. Vulnerability is likely to increase in many sectors, but this depends on adaptive capacity; Most human systems have considerable adaptive capacity. The region has well developed economies, extensive scientific and technical capabilities, disaster mitigation strategies, and biosecurity measures. However, there are likely to be considerable cost and institutional constraints to implementation of adaptation options. Some Indigenous communities have low adaptive capacity. Water security and coastal communities are the most vulnerable sectors; Natural systems have limited adaptive capacity. Projected rates of climate change are very likely to exceed rates of evolutionary adaptation in many species. Habitat loss and fragmentation are very likely to limit species migration in response to shifting climatic zones; Vulnerability is likely to rise due to an increase in extreme events. Economic damage from extreme weather is very likely to increase and provide major challenges for adaptation; Vulnerability is likely to be high by 2050 in a few identified hotspots. These include the Great Barrier Reef, eastern Queensland, the south-west, Murray-Darling Basin, the alps and Kakadu wetland