

Risks
Risks
The key impacts of current and emerging pressures, how likely and severe those risks are when management intervention and resilience are taken into account.
Overview for Risks
Even after management actions and resilience are taken into consideration, some pressures can continue to pose a risk to the environment. Identifying and assessing the risk to the environment examines both the likelihood that the impact will take place and the severity of anticipated consequences if it does occur. Risk assessment provides valuable information for determining the need to adjust policies or adapt management approaches to mitigate risks.
The key risks to the Australian environment include the pressures created by climate change, land-use change, habitat fragmentation and invasive species.
As described earlier in this report, strong evidence exists that the climate is changing at a rate unprecedented in the geological record. Climate change poses serious risks to Australia’s population, economy and environment. Without strong action to reduce greenhouse gas emissions, the world is likely to warm by 4 °C by 2100 (Sherwood et al. 2014). For Australia, this would mean temperature rises of 3–5 °C in coastal areas and 4–6 °C inland (CCA 2015).
Average rainfall in southern Australia is projected to decrease, with a likely increase in drought frequency and severity. Extreme daily rainfall events are projected to increase in both frequency and severity.
The sea levels around Australia are projected to rise further, with a subsequent increase in the frequency of extreme sea level events.
The likelihood and impact of risks posed by climate change (discussed in the ‘Pressures’ and ‘State and trends’ sections of this report) depend on the extent to which the implementation of the Paris Agreement is successful in limiting global warming to less than 2 °C. Holding global warming to below 2 °C would require reducing global greenhouse emissions by 40–70 per cent by 2050 compared with 2010 emissions. Effective adaptation policies and actions will also be required to minimise the adverse impact of inevitable climate change, even if global temperature increases are limited to 2 °C.
The cumulative impacts of individual management decisions present a significant risk to the ongoing sustainability of Australia’s land. This is exacerbated by government policies (such as vegetation clearing controls) that support further habitat loss and fragmentation. It is almost certain that the extent and connectivity of native vegetation will continue to decline. In addition, some land management practices, such as inappropriate application of fertilisers and pesticides, and poor irrigation, represent an ongoing risk.
It is clear that invasive species are a major ongoing risk to Australian biodiversity, inland waters and coasts, and this risk is likely to remain in the near future. Climate change may create conditions that exacerbate the range and impacts of invasive species.
Coastal environments are potentially the most at risk of all Australian environments because they simultaneously bear the brunt of population density and urbanisation, habitat loss, invasive species, the downstream impacts of agriculture, and the widespread effects of climate change, including sea level rise, erosion, storms and heat stress.
The risk from these and other pressures can be increased by inertia or lack of timely action before tipping points are reached. For example, lack of timely action can occur when an issue is raised but, because of complex procedures and/or the involvement of multiple jurisdictions and organisations, a decision is not made before an irreversible change occurs (e.g. extinction of a species). This risk can be reduced when there are:
- clearly defined management boundaries for avoiding tipping points
- effective and efficient procedures for responding to issues of concern
- adequate monitoring systems in place that identify when a pressure is approaching, or has reached, a boundary or tipping point.
There is also a risk that efforts to improve policy and management will continue to be hampered by poor understanding of the broader impacts of drivers and pressures on the environment, and the flow-on effects on economic activity and human communities.
SoE 2016 identifies a number of other risks to the Australian environment:
- Built environment
- increased economic impact and loss of human life as a result of prolonged extreme heat events
- Heritage
- replacement of heritage-listed buildings with new buildings, including ones perceived as ‘green’ (and therefore more environmentally friendly), rather than retaining and adapting old buildings
- loss of traditional knowledge that threatens Indigenous cultural heritage
- incremental destruction caused by the focus of development approvals on site-specific heritage impact, rather than cumulative incremental impact
- resourcing, including limited funding, lack of incentives, and neglect arising from rural population decline or the loss of specialist heritage trade skills
- development and resource extraction projects
- Biodiversity
- inadequate programs and processes for collecting relevant and adequate data to provide early warning of threats and opportunities for biodiversity management
- inappropriate development in urban and peri-urban areas, and failure to manage human demands on the environment
- Land
- run-off from managed land that will irreversibly damage parts of aquatic and marine systems, and persistence of this damage even if run-off and nutrient loads are later reduced
- Inland water
- increased extraction of water from inland water and groundwater systems, which will change water flow regimes and groundwater conditions
- salinisation of major rivers and aquifers because of historical land clearance
- extraction and pressure from new sources such as shale gas, coal-seam gas and large coalmining developments, which threaten groundwater quality
- Coasts
- increasing population density in coastal regions, and the pollution, habitat loss and invasions associated with urbanisation, trade and industrialisation
- microplastics
- Marine environment
- marine debris and microplastics.
At a glance
During the past 50 years or so since the first clean air Acts were introduced in Australian jurisdictions, state and territory environment protection agencies (often working together with local government) have successfully employed regulatory and nonregulatory measures to greatly reduce threats to urban air quality from industrial, commercial and domestic activities. The risk of this situation changing markedly during the next decade is assessed as low, despite continuing growth of the economy. The lack of effective control measures for smoke pollution from domestic wood heaters needs to be addressed. Although stronger compliance with standards, improved in-service operation and behavioural changes offer some opportunity for cleaner air, the only long-term solution is the same as that for backyard burning, which was banned across urban areas about 30 years ago.
Motor vehicles are the main diffuse source of air pollution in urban areas, and the size of the Australian fleet is continuing to grow, as are the distances travelled. Despite this, projections to 2030 indicate a continued decline in vehicle emissions of most air pollutants. This positive outlook is strengthened by the Australian Government’s establishment in 2015 of the Ministerial Forum on Motor Vehicle Emissions to investigate ways to improve the energy productivity of transport, improve air quality and reduce greenhouse gas emissions. Considering these competing factors, the risk of a marked deterioration in urban air quality in the next decade is conservatively assessed as medium.
The higher temperatures associated with climate change are expected to elevate ambient levels of volatile organic compounds, increasing the potential for ozone pollution in Australia’s larger metropolitan centres, where peak ozone levels already exceed national air quality standards at times. Climate change is also expected to affect the likelihood of bushfires, which, depending on location, can cause very serious particulate pollution in population centres. The level of risk associated with these outcomes is assessed as medium.
At a glance
Extreme weather and natural events are considered the largest risks to the built environment. The likelihood of occurrence of these events is considered ‘almost certain’, with the impacts variable, depending on the risk. Despite the assessment that the built environment is quite resilient to extreme weather events (in the longer term), both mega-storms and mega-fires are considered catastrophic because of the immediate consequences of these events for property and infrastructure, loss of amenity, and human casualties. These risks have been elevated from ‘likely’ in 2011 to ‘almost certain’ in 2016. Pressures on the built environment from the cost and impacts of extreme mega-weather events will continue to increase. Population growth is also bringing pressure for settlement in places that are at greater risk from climate events.
In all cases, climate and weather risks are compounded if there is poor design of buildings and cities; poor regulation, enforcement and compliance of building guidelines; or inadequate and inappropriate infrastructure.
At a glance
An understanding of the risks associated with Australia’s climate will lead to improved action plans to adapt to the changes predicted to occur. Our climate is a dynamic system; therefore, the risks need to be re-evaluated frequently.
Recent climate change projections for Australia from the Intergovernmental Panel on Climate Change, CSIRO and the Bureau of Meteorology have modelled how Australia’s climate is likely to evolve during the next century.
In the past century, Australia’s climate has warmed by 1 °C. Mean temperatures and extreme temperatures are projected to increase, with more hot days and fewer cold days. Australia is forecast to experience increased heatwaves, leading to increased wildfire incidence and health problems (heat stress); longer droughts, extending further geographically than they have done in the past; flooding from more intense storm activity; sea level rise, leading to coastal damage; and loss of ecosystems.
Average rainfall in southern Australia is projected to decrease, with a likely increase in drought frequency and severity. Extreme daily rainfall events are projected to increase in both frequency and severity.
The sea levels around Australia are projected to rise further, with a subsequent increase in the frequency of extreme sea level events.
At a glance
Australia’s heritage continues to be under-resourced, and at risk from both natural and human factors.
Some risks, such as catastrophic fire or extreme weather events, may not be easily mitigated, and instead may require post-event response. Events such as the removal of statutory protection or large-scale resource extraction from reserved lands could have catastrophic impact, but would arise from deliberate decisions and are unlikely. However, major risks arise from the effects of climate change, such as damage from extreme weather events, more frequent fires, loss of habitat or increases in invasive species. Indigenous cultural heritage continues to be at risk from some loss of traditional knowledge and incremental destruction, because development approval affords priority to site-specific heritage impact, rather than cumulative incremental impact. Resourcing is also a major risk factor, including lack of data to inform decision-making, limited funding, lack of incentives, neglect arising from rural population decline, or the loss of specialist heritage trade skills. Development and resource extraction projects continue to threaten the nation’s heritage at both a landscape and individual site scale. Development impacts are at risk of being exacerbated by inadequate pre-existing survey, assessment and statutory protection.
The commitment to national leadership in the Australian Heritage Strategy should reduce the overall risk to Australia’s heritage. However, continuing reduction in the public-sector resources allocated for heritage presents a growing risk to long-term conservation of heritage values.
At a glance
Escalation of existing risks such as invasive species, climate change and changing fire regimes, and the interactions between these risks, will continue to exert significant and widespread changes on biodiversity.
The importance of some risks, or at least the perception of those risks, has decreased slightly. For others, it has increased. Based on a reassessment of the risks identified in 2011, the 2 highest-ranked risks in 2016 are the failure of processes for adequate data collection to provide early warning of threats and opportunities, and pressures from urban and peri-urban growth. Both are almost certain in terms of likelihood, and almost certain to have major consequences. Both have increased in likelihood since 2011, from possible to almost certain.
Ideas about ‘megatrends’ and ‘megashocks’ are new to the state of the environment biodiversity discussion in 2016. Both megatrends and megashocks have the potential to significantly change the state of Australia’s biodiversity.
At a glance
The predicted impacts of climate change pose the greatest risks to Australia’s land environment. These impacts include changes in the distribution and success of native species and ecosystems; the viability of some agricultural enterprises; and the impact of natural processes and events, such as extreme weather, with consequent impacts on environmental processes and function.
Inadequate investment in monitoring change, and in developing and instituting appropriate management responses, poses a significant risk that we will be unable to prevent, reduce or adapt to both current and future challenges.
At a glance
Risks to inland water environments include direct risks (such as direct water extraction, or changes in run-off and recharge) and indirect risks (such as expansion of invasive species because of increased tourism).
Climate changes may produce both types of risks. Updated climate projections, including rainfall, were released in 2015. For northern Australia, models offer diverse results; natural climate variability remains the major driver of rainfall changes for the next few decades, with variable outlooks thereafter. There is high confidence in future increases in the intensity of extreme rainfall events, so the risk of extreme wet periods and floods seems likely to increase. In the rangelands, there is high confidence in long-term rainfall declines. The direction and magnitude of annual and summer rainfall changes are less certain, whereas the risks of extreme rainfall and time spent in drought will increase. For the southern and south-western flatlands, there is high confidence that winter, spring and annual rainfalls will decrease in both the medium and longer term, and high confidence that extreme rainfall events will intensify. For much of the Murray–Darling Basin, there is a mix of medium and high confidence that, by late in the century, there will be decreases in winter–spring ‘cool-season’ rainfall. Warm-season and summer–autumn rainfall is not projected to change significantly. In other parts of Australia—the south-east and Tasmania—there is high confidence in winter and spring rainfall decreases later this century, except for Tasmania, where there is medium confidence in increases in winter rainfall. There is also high confidence in future increases in the intensity of extreme rainfall events.
Risks from water resource development are ever present. Proposals for significant infrastructure development in the coming decades raise risks of interrupting natural flow regimes, affecting waterscape connectivity and impeding aquatic ecosystem processes that require the run of the river. Risks in developing Australia’s north include surface-water regime change, surface-water pollution, groundwater extraction, seawater intrusion, and accelerated spread of pest plants and animals. However, we have a significant body of practice and knowledge to help avoid the land and water management mistakes of the past.
A range of risks arise from current and proposed coal-seam gas and large coalmining developments, and these will be informed by the Bioregional Assessment Programme.
At a glance
Despite concerted efforts to manage pressures on the coast, there remains residual risk that impacts will still occur. Here we categorise each of the pressures identified in this report in terms of their likelihood to cause impact and the severity of that impact, once current management has taken effect.
Risks to the coast related to climate change (sea level rise, change in climate and weather) are of most concern, because they are almost certain, their impacts would be catastrophic, and they are currently relatively unmanaged. Also of great concern are risks from invasive species, because these can have ecologically dire consequences but are very difficult to safeguard against. Microplastics are a significant unknown risk, as their introduction to, and spread through, the coastal environment is growing far more rapidly than research and understanding of their impact.
Risks associated with managed pressures generally represent inadequacies of current management to fully eliminate their impacts, which is expected given limited resources and acceptance of minor impacts. Some managed pressures are still considered to have major or moderate impacts because of their large extent and diffuse nature; examples are estuarine and coastal pollution and recreational fishing.
At a glance
Avoidance and mitigation measures, which are the primary strategies for managing impacts of activities on the marine environment, may not address all impacts associated with the activities. Management may be absent or only partially effective, there may be some impacts that are difficult to avoid or mitigate, and the severity of some impacts may be unknown. These impacts are regarded as residual risks.
Assessment of the residual risks associated with pressures on the marine environment identified that those associated with climate change and marine debris were the most extensive because effective management is lacking. Management frameworks currently in place for most other pressures reduce either the likelihood of residual risks (e.g. commercial fishing impacts on habitats) or the impact of residual risks (e.g. planned oil and gas exploration and production activities).
Ecological risk assessments provide a quantitative and often hierarchical framework for identifying risks associated with activities and their probability. Their use would improve the identification of residual risks in the future, and increase opportunities for the more effective use of avoidance and mitigation options. Application of formal ecological risk assessment frameworks within the Australian marine environment has, to date, been limited.
Environmental offsets, as set out in the Australian Government’s EPBC Act Environmental Offsets Policy 2012, are designed to ensure no net environmental loss as a result of residual risks. The suitability of any proposed offsets is considered as part of the assessment of actions under the Environment Protection and Biodiversity Conservation Act 1999 and is not justification for a proposal to go ahead without adequate avoidance or mitigation, if at all. Similar policies have been set out for various sectors by some state governments and some industry sectors. However, evaluation of the success of offsets in achieving environmentally sustainable outcomes is often not integrated into approval processes. The recently releasedPolicy statement: advanced environmental offsets under the EPBC Act may improve environmental outcomes through implementation of offsets before any impact occurs, and a more strategic approach to the application of offsets.
At a glance
As for other regions, distant human activities can contribute to the key risks to the Antarctic environment, including global population, economic pressures and the effects of climate change. Management can mitigate many of the population and economic impacts, and climate change will be the main and uncontrollable pressure bringing about change.