Abstract: 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 and, in New Zealand, in Northland and some eastern regions (high confidence). • Ongoing coastal development and population growth, in areas such as Cairns and south-east Queensland (Australia) and Northland to Bay of Plenty (New Zealand), are projected to exacerbate risks from sea-level rise and increases in the severity and frequency of storms and coastal flooding by 2050 (high confidence). • 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, sub-Antarctic islands and alpine areas of both countries (very high confidence). • 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 heatwaves, causing more deaths and more blackouts (high confidence). • Production from agriculture and forestry is projected to decline by 2030 over much of southern and eastern Australia, and over parts of eastern New Zealand, due to increased drought and fire. However, in New Zealand, initial benefits to agriculture and forestry are projected in western and southern areas and close to major rivers due to a longer growing season, less frost and increased rainfall (high confidence). 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 the implementation of adaptation options (high confidence). Some Indigenous communities have low adaptive capacity (medium confidence). Water security and coastal communities are the most vulnerable sectors (high confidence). • Natural systems have limited adaptive capacity: Projected rates of climate change are very likely to exceed rates of evolutionary adaptation in many species (high confidence). Habitat loss and fragmentation are very likely to limit species migration in response to shifting climatic zones (high confidence). • 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 (high confidence). • Vulnerability is likely to be high by 2050 in a few identified hotspots: In Australia, these include the Great Barrier Reef, eastern Queensland, the South-West, Murray-Darling Basin, the Alps and Kakadu wetlands; in New Zealand, these include the Bay of Plenty, Northland, eastern regions and the Southern Alps (medium confidence)
Suggested Citation
Hennessy, K., B. Fitzharris, B.C. Bates, N. Harvey, S.M. Howden, L. Hughes, J. Salinger, R. Warrick,
2007,
Australia and New Zealand. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,
Book Section,
viewed 10 February 2025,
https://www.nintione.com.au/?p=5170.