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Part 4 1 Introduction State of the Environment Atmosphere Atmosphere 187 | State of the Environment Report - Victoria 2008
A0 Introduction Key Findings •V ictoria has warmed by 0.6°C since the 1950s; a faster rate of warming than the Australian average and the last ten years have been hotter than average in Victoria, with 2007 being the hottest year on record. •S ince 1990, changes to both global temperature and sea level have tracked at the upper limit of projections, indicating that projections may be underestimates of likely climate change scenarios. •V ictoria’s greenhouse emissions have increased by approximately 12% since 1990. •F ull recovery of stratospheric ozone is possible but is highly dependent upon adherence of both developed and developing countries to international agreements. In addition, an enhanced greenhouse effect and future atmospheric concentration of nitrous oxide and methane may reverse anticipated ozone recovery. •B y international standards, Victoria has good air quality. Increased frequency and severity of bushfires, and low rainfall 4 Atmosphere attributed to climate change, will produce added pressures on air quality. The higher temperatures may also lead to a greater potential for ozone formation leading to increased incidence of smog. 4.1 •A ustralia has particular vulnerabilities to climate change and environmental degradation, but these should not act as a constraint on its environmental policy responses, rather they increase the risk of not acting strongly and urgently to climate change risks. •T he window of opportunity to stabilise levels of greenhouse gas emissions is rapidly diminishing. | 188
Part 4 State of the Environment Atmosphere Victorian atmosphere assets broad scientific acceptance that climate Adaptation to climate change as a policy change is unequivocal this report will is necessary to cope with the change The Earth’s atmosphere is about 800 focus on indicators of climate change. The locked into the system by the level of kilometres thick. It protects living things other issues reported are stratospheric greenhouse gases already emitted. This from harmful solar radiation and ensures ozone and air quality, both themselves situation has come about as a result a suitable temperature range for life as subject to the effects of climate change. of a failure by the global community to well as providing the air that we breathe agree on how to adequately mitigate and providing the transport mechanism Climate change is viewed as the most against climate change. However, if for water molecules that fall as rain. Air critical of all environmental issues as it global greenhouse gas emissions are not is a mixture of oxygen, nitrogen, carbon has the potential to drive radical systemic brought under control and subsequently dioxide and other gases such as hydrogen change, create consequential economic reduced, it will condemn Victorians to and ozone. These gases are densest in turbulence, and affect people both here dangerous climate change, including the boundary layer at the Earth’s surface and globally. Victoria has been a leader in further reductions in water availability, where a very thin skin of air supports taking action on climate change. By 2010 sea level rise, migration of farming, and life (see Figure A 0.1). The atmosphere Australia’s Carbon Pollution Reduction also to wider global risks to trade and the provides essential ecosystem services, Scheme will be introduced. Australia forced migration of peoples from severely but continued provision of those services and Victoria are now participating in affected regions of the world. is threatened by human activities. international movements to gain a global agreement on reducing greenhouse gas A problem recognised in the 1980s was A key service provided by the atmosphere emissions and adapting to an inevitably that certain chemicals had the capacity is moderation of the climate. Victoria’s changed climate. This is a fast-moving to damage the ozone layer, the layer in climate is naturally highly variable. El Niño, area of policy, and the evolution of the atmosphere that protects the planet La Niña and the Southern Oscillation measures will continue well beyond the from harmful solar radiation. This was create variable weather patterns, with the release of this report. The commentary in the first global atmosphere problem. The effect being more marked in the north this report should be viewed, therefore, as breakdown of the ozone layer as a result of the State1. Traditionally reports on the part of a dynamic pattern of governmental, of aerosols such as chlorofluorocarbons state of the environment have considered industry amd community effort which has lead to an international collaboration in the state of the climate. However, without a long way to go. order to reduce and reverse the damage. excluding natural variability, given the The Montréal Protocol on Substances that Deplete the Ozone Layer came into force Figure A0.1 Chemical and transport processes in the atmosphere in 1989. This brought in the first effective Source: Garnaut 2008 global ban on discharge of certain atmospheric substances. In addition to a global depletion, in the 1980s a hole in the ozone layer (a pronounced thinning, predominantly in the lower portion of the ozone layer), was discovered over Antarctica. At its maximum, about the year 2000, the hole was approximately 30 million km2, almost four times the size of Australia, and its depth was down to 60% of 1970s ozone thickness. It has since stabilised at this size, with significant year-to-year variations largely driven by stratospheric temperature fluctuations. In policy terms air quality, the relative state of a local or regional airshed, was the first obvious issue related to the atmosphere to prompt community reaction and policy action. It was a switch to fossil fuels, coal and oil, that underwrote the industrial revolution. Unknown then, this range of gases, particularly those involving carbon, provided the seeds of today’s greenhouse problem. This was also the period when urbanisation accelerated, as industrial employment released individuals from a direct relationship with and dependence on the land. The first laissez-faire industrial cities were the locus of the new poor air quality, compounded after the Second World War by the increasingly universal adoption of the internal combustion engine as the source of individual mobility. 189 | State of the Environment Report - Victoria 2008
Not surprisingly a reduction in air pollution km2) and depth (60% ozone losses since Pressures on Victoria’s and its direct health consequences was the late 1970s) about the year 2000, atmosphere the first and most significant subject resulting in 50% to 130% more ultraviolet-B There is now overwhelming evidence that of modern environmental objectives. radiation reaching the Earth’s surface. It recent rapid climate change is linked to With this came the argument that has since stabilised. Major ozone losses elevated concentrations of greenhouse most of these discharges were an over Melbourne from the late 1970s until gases in the atmosphere. Human activities unpriced externalisation of wastes to the the early 1990s have been 7% - 8% per are the main contributor to increased environment and that the costs were borne decade. Ultraviolet levels under clear-sky greenhouse-gas concentrations, largely in degraded and unhealthy air. conditions increased by 10% per decade through the combustion of fossil fuels, over southern Australia from the late 1970s This section shows that motor vehicles which releases carbon dioxide and other to the late 1990s. Since the late 1990s and fires are significant sources of greenhouse gases. ultraviolet levels have declined by 5%. pollutants that lead to formation of smog. Observations and modelling of the The Victorian EPA has led the State to an Ozone depletion halted in the late 1990s climate system lead to the conclusion air quality standard that by international leaving ozone levels over Melbourne that enhanced concentrations of standards is very good. relatively stable, but at a level at least greenhouse gases are the dominant 10% lower than they were in the late Overall Condition cause of warming during the past several 1950s. Despite longer term stabilisation, decades2. The IPCC states that “no known Condition of the climate the lowest ozone level recorded over mode of internal variability leads to such Melbourne since 1956 was seen in the It can be argued that the single greatest environmental, social and economic summer of 2006/2007. widespread, near universal warming as has been observed in the past few decades”3, 4 challenge facing Australia and Victoria Stratospheric ozone recovery may have which leaves external factors, such as Atmosphere is climate change. Climate Change is commenced in 2000, but is currently human activities, as the most likely causes seen as a driving force for environmental masked by solar cycle effects. Significant of the warming. The IPCC4 in its Fourth change, and the topic is widely covered in ozone recovery is expected over the next Assessment Report in 2007 concluded 4.1 this Report. 5 years. Full recovery of stratospheric that anthropogenic greenhouse gas ozone is possible but highly dependent emissions are very likely (greater than Victoria has warmed by 0.6°C since the upon adherence of both developed and 90% probability) to have c aused most of 1950s; a faster rate of warming than the developing countries to international the observed increases in global average Australian average. The last ten years agreements. In addition, an enhanced temperature since the mid-20th century. have been hotter than average in Victoria, greenhouse effect and future atmospheric with 2007 being the hottest year on record. Whilst use of ozone depleting substances concentration of nitrous oxide and Victoria experienced a hot and dry period has been phased out reducing the methane may reverse anticipated ozone between 1997 and 2007. In parts of pressure on the ozone layer, additional recovery. northern Victoria this decade is the driest factors may mean that ozone recovery since the droughts of 1938-1945 and Condition of air may not occur by 2040 as previously 1895-1902. Since 1961 global average sea The condition of Victoria’s air can be predicted. One of the consequences level has risen by approximately 10 cm. considered good. However the State of climate change is that as the lower Williamstown has registered a sea level Environmental Protection Policies (SEPPs) atmosphere warms, the upper atmosphere rise of 18 cm over the last hundred years. made by the Victorian EPA to regulate cools. A cooler stratosphere means more these matters show a need for a continued polar stratospheric clouds and more Since 1990 carbon dioxide emissions, high level of investment and effort in ozone depletion. Climate change may mean global temperature and sea level compliance and monitoring. Levels of delay full ozone recovery by as much rise have tracked at the upper limit of fine particles and ozone do not always as 50 years5. In addition, the long-term projections, indicating that projections meet the objectives in Victoria’s ambient growth of nitrous oxide in the atmosphere may be underestimates of likely climate air quality policy and in those instances may cause significant ozone depletion change scenarios. people are exposed to adverse health after about 2060. Victoria’s greenhouse emissions have impacts. Ozone in air is distinguished The pressures on Victoria’s air quality are increased by approximately 12% since from ozone in the stratosphere (commonly increasing with its growing population and 1990. In 2006, the stationary and transport known as the ozone layer) which has the economy. The most significant sources energy sectors accounted for 85% of total beneficial effect of absorbing harmful of fine particle emissions in Victoria are greenhouse gas emissions in Victoria. radiation. from dust storms, bushfires, industry Condition of stratospheric ozone By international standards, Victoria has and motor vehicles. Wood heaters and good air quality which has been relatively planned burning can also be a significant Emission of certain chemicals such as stable over the last decade despite source of particles. Motor vehicles are chlorofluorocarbons (CFCs) leads to the increased pressures from a growing a major source of the pollutants that depletion of stratospheric ozone, exposing population and economy. Bushfires and lead to formation of smog, which can both marine and terrestrial life to additional dust storms resulting from a prolonged also form downwind of bushfires. As the harmful amounts of ultraviolet radiation. below-average rainfall have recently climate changes, average temperatures Global emission of those substances affected air quality across Victoria with air are predicted to increase leading to an peaked in the late 1980s to early 1990s at quality being poor in 2003 and 2006 due increase in dust storms and fire. Higher 2.1 million tonnes per year, and by 2005 to the impact of severe bushfires. temperatures will also cause greater had declined by 70% to 0.5 million tonnes. emissions of pollutants and an increase in Worldwide ozone losses of 4% per decade Increased frequency and severity of the speed of the chemical reactions that occurred from the late 1970s until the late bushfires, and drought attributed to lead to formation of smog. 1990s. climate change, will produce added The Antarctic ozone hole reached a pressures on air quality. The higher maximum area (approximately 30 million temperatures predicted may also lead to a greater potential for ozone formation. | 190
Part 4 State of the Environment Atmosphere Management Responses and production of ODSs in a limited The Montréal Protocol on substances period. Due to its results it is considered that deplete the atmosphere, the Responses to the challenge of climate very successful. The Multilateral Fund principal global mechanism responsible change – by governments, business and for the Implementation of the Montréal for the decrease in global atmospheric industry and by the wider community – Protocol has been established to help concentrations ODSs has been highly are currently dominating international, developing countries in their efforts to successful in phasing out the use national and local policy debates around phase out ODSs. and production of ODSs in a limited environmental sustainability. Those period. The Multilateral Fund for the responses are important not only to Improving air quality Implementation of the Montréal Protocol address the problem of climate change Response Name should be useful in assisting developing but they are also relevant for adressing State Environment Protection Policy countries in their efforts to phase out the associated atmospheric issues of (Ambient Air Quality) ODSs. Despite the success of these stratospheric ozone depletion and air Responsible Authority responses there are still some ozone quality. The responses presented here Victorian Environment Protection depleting substances in use in Victoria. are the overarching tools used to address Authority These are used for fumigation of shipping these issues. They are considered in containers and in the grain and strawberry further detail in subsequent sections of Response Type runner industries. this part of the report. Policy The Victorian EPA, the second such Reducing Greenhouse Emissions The Ambient Air Quality SEPP contains the organisation to be established in the Response Name national indicators, standards, goals and world, has been working to improve United Nations Framework Convention monitoring and reporting protocol of the Victoria’s air quality for over 35 years. on Climate Change (UNFCCC) National Environment Protection Measure Victoria established its first statewide for Ambient Air Quality (AAQ NEPM). policy framework for the management of Responsible Authority Currently there are 16 EPA operated air Commonwealth Government air quality in 1981, with the development quality stations (12 in Melbourne, 2 in of the State Environment Protection Response Type Geelong and 2 in the Latrobe Valley) that Policy (SEPP) (The Air Environment). The International Agreement monitor the common air pollutants and current regulatory framework for protecting some air toxics. Site-specific monitoring Victoria’s air environment is provided by The UNFCCC was one of three is also undertaken to better understand the Ambient Air Quality and Air Quality conventions adopted at the 1992 Rio local or sub-regional air pollution. The data Management SEPPs. These tools have Earth Summit. The central objective of the provides important information on whether been highly successful in guiding EPA’s UNFCCC is to stabilise greenhouse gas air quality objectives are being met, and monitoring and reporting on air quality. concentrations at a level where dangerous allows trends in air quality to be tracked. That knowledge enables EPA to work with human interference with the climate This information is used to guide the the community, industry and government system is prevented. development of Government policies and to tackle sources of pollution. However, Upon ratification, signatory governments strategies to improve Victoria’s air quality. there are some areas where improvements are committed to a voluntary non-binding could potentially be made. This is likely to aim to reduce greenhouse gases. The Evaluation of atmosphere require action from a range of agencies main outcome of the UNFCCC to date responses across Government. has been the Kyoto Protocol, negotiated Climate change is already unavoidable and signed in 1997. Under the Protocol, due to existing levels of greenhouse developed countries have been given gases in the atmosphere. While climate Recommendations the initial responsibility in tackling climate change action has traditionally focused A0.1 Encourage an Australian program change as they are the source of most on mitigation, governments are becoming of action on climate change which greenhouse gas emissions to date. increasingly attentive to adaptation as sees effective multilateral and bilateral Developing countries have no immediate the reality of unavoidable climate change action and develop a strong program of restrictions under the Convention. becomes clear. Whilst Victoria’s own state-based mitigation policy measures Reducing Emissions of Ozone Depleting emissions on a global scale are small, including building a climate change Substances per capita they are amongst the worst in “test” into all major policy, infrastructure the world. This shows a real opportunity and expenditure decisions. Response Name for change and provides the means by Montréal Protocol on Substances That A0.2 Continue to support CSIRO which Victoria could become a leader in Deplete the Ozone Layer monitoring and reporting of atmospheric emissions reduction. Such skills would be ozone concentrations and review Responsible Authority transferable to other nations that might be developments that may lead to suitable Department of the Environment, Water, struggling with ways to reduce emissions greenhouse neutral replacements for Heritage and the Arts and importantly, provide an opportunity to ozone depleting substances that are Response type demonstrate a pathway to a low carbon still in use. International Treaty economy whilst maintaining economic growth. A0.3 Continue to support the EPA in The Montréal Protocol is the principle monitoring and reporting air quality and mechanism responsible for the decrease actively seek solutions to managing in global atmospheric concentrations of air quality in light of the increased ozone depleting substances (ODS) since pressures predicted from a growing 1998. The Protocol came into force in population and climate change. 1989 and its main purpose is to protect the ozone layer by phasing out the use 191 | State of the Environment Report - Victoria 2008
A1 Climate change Key findings • In 2007, the IPCC declared that climate • In its 2007 report, the United Nations change is ‘unequivocal’ and, with a Intergovernmental Panel on Climate •G lobal atmospheric concentrations probability over 90%, this change is due Change (IPCC) found that carbon of greenhouse gases have increased to post-industrial human activity. dioxide emissions need to peak no later markedly as a result of human activities than 2015 and be reduced by 50-85% since 1750 and now far exceed pre- •S ince 1990, carbon dioxide emissions, by 2050 (from 2000 levels) to limit industrial values. Impacts of climate global mean temperatures and sea global average temperature increases change on stratospheric ozone; air levels have tracked at the upper limit of to 2.0 - 2.4° C. quality; land and biodiversity; inland projections, indicating that projections waters; and coasts, estuaries and the may be underestimates of likely •T he 2007 United Nations Framework sea are addressed throughout this climate change scenarios. The greater Convention on Climate Change report. the warming, the greater the risk of (UNFCCC) Bali Roadmap and IPCC tipping into irreversible climate change. Working Group Reports indicated •T here are large natural year to year Climate change feedback loops further potential greenhouse gas emissions variations in climate. Natural climate increase these risks. reductions by developed countries of variability will influence actual warming 25-40% by 2020 and 80-95% by 2050 values in any single year or decade. Projections (from 1990 levels). The global warming influence due to •P rojections indicate that by 2030 increasing greenhouse gases is at •A ustralia, and Victoria, have committed warming in Victoria is likely to global scales and cumulative over many to reducing emissions by 60% by 2050 range from 0.6°C to 1.2°C on 1990 years. At short time scales, natural variability can offset that warming temperatures and by 2070 from 0.9°C to 3.8°C. The 2030 rise is largely locked from 2000 levels, with interim targets yet to be announced. 4 influence and cause short term cooling. Atmosphere in by the current level of emissions, •E arly global action to reduce The long-term warming trend is with the 2070 projections dependent on greenhouse gas emissions reduces the unequivocal. rates of global growth and measures risks associated with climate change, •A ustralia naturally has a highly variable put in place to reduce greenhouse gas reduces long term costs and provides 4.1 climate. Because of its geography, emissions. greater flexibility should emerging Australia has further vulnerability to science cause mitigation responses to • In most Victorian catchments, runoff damage through variations induced be adjusted over time. into waterways is projected to decrease by climate change than most other between 5% and 45% by 2030 and •W hile being responsible for only 1.5% developed countries. between 5% and 50% by 2070. of total global emissions, Australia is Observed changes the 14th largest emitter of greenhouse •F ire risk is forecast to increase gases in the world. On a per capita •V ictoria has warmed by 0.6°C since the substantially in Victoria, with the number scale of the top 25 emitting countries, 1950s - a faster rate of warming than of very high or extreme fire danger days Australia is the second highest. the Australian average. The last ten across south-eastern Australia expected years have been hotter than average to increase by up to 25% by 2020 and • In 2006, approximately one fifth of in Victoria, with 2007 being the hottest up to 230% by 2050. Australia’s greenhouse gas emissions year on record. Six out of Victoria’s ten came from Victoria. Between 1990 and •B y 2070 drought frequency is likely to hottest years on record have occurred 2006, Victoria’s emissions grew by increase by between 10% and 80% in since 1990. 12% and could increase 40% above the southern half of the State and by 2000 levels by 2050 in the absence of •R ainfall during the last ten years has between 10% and 60% in the northern effective mitigation. been markedly lower than the long-term half. average, with 2007 being one of the •T he Australian Garnaut Climate Change •M ore frequent extreme weather events three driest years since 1900. Review has proposed that Australia are predicted, with increasing damage should offer to play its full, proportionate •S erious rainfall deficiencies over the from flooding, high winds and coastal part in a global agreement designed past 11 years have reduced inflows storm surges and inundation; a current to achieve a 450 ppm CO2-e to storages 30–60% below long-term 1 in 100 year extreme storm surge could concentration. However, it further averages. Water scarcity has been occur around every 5 years by 2070. proposes not to focus on a single statewide in extent, exacerbated by Projected sea level rises will further trajectory, but to have a set of options high temperatures, and has worsened exacerbate these problems. available during the negotiations for over time, with flow in the Murray and Context and policy responses the international post Kyoto Protocol Melbourne storages reaching record •G lobally, between 1970 and 2004, arrangements. lows in 2006. greenhouse gas emissions covered by •M omentum has built rapidly in terms •S ince 1961 global average sea the Kyoto Protocol have increased by of public awareness and support for level rose approximately 10 cm. 70% (24% since 1990). Government action, however, in the Williamstown has registered a sea level •W ithout additional policies, global context of current global economic rise of 18 cm over the last hundred greenhouse gas emissions are instability and ongoing concerns about years. projected to increase by 25-90% by international economic competitiveness, •V ictoria’s greenhouse gas emissions 2030, relative to 2000. strong community support will continue have increased by approximately 12% to be required. since 1990. •C ritical decisions on Australia’s and the world’s commitment to reduce greenhouse gas emissions will be made in 2009. | 192
Part 4 State of the Environment Atmosphere Description The top 25 greenhouse gas emitting Scientific evidence countries in the world together account The climate challenge There is now overwhelming evidence that for over 87% of global emissions. While recent rapid climate change is linked to Climate change confronts humanity with being responsible for only 1.5% of total elevated concentrations of greenhouse the possibility of catastrophic change to global emissions6, Australia is the 14th gases in the atmosphere. Human activities life on Earth. largest emitter of greenhouse gases in the are the main contributor to increased Worldwide scientific collaboration is world. On a per capita scale of the top 25 greenhouse gas concentrations, largely presenting a range of increasingly emitting countries, Australia is the second through the combustion of fossil fuels disturbing scenarios. These stem from highest7. In 2006, approximately one and land clearing, which releases carbon a combination of key human activities, fifth of Australia’s emissions came from dioxide and other greenhouse gases. namely: the dramatic growth in global Victoria8, which generated over 120 million tonnes of greenhouse gases. Between Observations and modelling of the greenhouse gas emissions since the 1990 (the base year used for greenhouse climate system lead to the conclusion that industrial revolution, the consumption of emissions monitoring under the Kyoto enhanced concentrations of greenhouse fossil fuels and the continued clearing Protocol) and 2006, Victoria’s emissions gases are the dominant cause of warming of forests and land for agriculture and grew by 12%9. during the past several decades11. The settlements. These factors, coupled Intergovernmental Panel on Climate with a lack of global consensus and The developed world is largely responsible Change (IPCC) states that “no known progress in reversing these trends, have for current global levels of greenhouse gas mode of internal variability leads to such turned the risk of catastrophic damage concentrations. Developing countries, in widespread, near universal warming as has to the economy, society and the natural particular the fast growing economies of been observed in the past few decades”12, environment from a possibility to a China, India, Brazil and others are seeking which leaves external factors, such as probability within our lifetimes. to lift the living standards of their societies human activities, as the most likely causes Tackling climate change throws up some and will soon become some of the largest of the warming. The IPCC13 in its Fourth very difficult challenges. The first is that greenhouse gas emitting countries in the Assessment Report, 2007, concluded people cannot immediately visualise world. Without mitigation, developing that anthropogenic (human-induced) it – it happens slowly, imperceptibly. The countries would account for about 90% greenhouse gas emissions are very likely, impacts have long lead times but strong of the emissions growth over the next with greater than 90% probability, to have action has to occur now if risks and their decade and beyond10. In international caused most of the observed increases in associated costs are to be avoided. Up negotiations, they attribute the changing global average temperature since the mid- front costs must be borne now to bring climate to ‘the West’ and look to the 20th century. It further describes climate benefits and reduced costs in the future. developed world to take responsibility for change as ‘unequivocal’. Climate change requires us to measure its historical emissions, and to take the lead in global emissions reduction efforts. The most recent deliberations of the how we value the welfare of future Developed countries, including Australia, international and Australian scientific generations relative to our own. have formally agreed to lead in responding communities are discussed in detail in Global action is required, based to climate change. In reality, the world this section. They point to ever stronger on principles of international and needs both developed and developing conclusions that greenhouse gas intergenerational equity if all nations are countries to take urgent action on the level emissions are growing at a rate beyond to be engaged. However the world is of greenhouse gases. that expected even three years ago, and composed of sovereign nations which that impacts are tracking at the upper historically pursue their own best interests. Nevertheless, the United States of America limits of projections in the IPCC scenarios. Achieving international agreement poses and until recently, Australia, were amongst Understanding of feedback systems a huge challenge for the world community. the few developed countries not to take and thresholds in the climate system is In conducting his Climate Change Review, climate change seriously. Powerful still incomplete, raising the possibility of Professor Ross Garnaut declared “There is internal interests argued and continue to irreversible climate change and climate a chance, just a chance that humanity will argue that the science is wrong and the change happening faster than previously act in time and in ways that reduce the risk threat is without foundation. These voices expected. of climate change to acceptable levels”. are still influential and they argue strongly for delayed or no action. Certainly they The Australian Garnaut Climate Change Historically, attempts at gaining seem to be heavily involved in arguing for Review Report states “We will delude international agreements have often an ever slower response. ourselves if we think that scientific foundered on the so-called ‘north- uncertainties are cause for delay. … south divide’ between developed and Delaying now is not postponing a developing nations. Over the past 150- decision. To delay is to deliberately choose 200 years, developed nations have been to avoid effective steps to reduce the risks able to lift their societies out of poverty, of climate change to an acceptable level.” based on the benefits of industrialisation. A major consequence of this economic growth, however, has been greenhouse gas emissions polluting the Earth’s atmosphere. 193 | State of the Environment Report - Victoria 2008
Australia’s vulnerability In summary, new ecosystems will The UK Government’s Stern Report, the replace the existing systems with major Garnaut Climate Change Review and Australia is particularly vulnerable both to risks for productive agriculture and the Australian business peak bodies have the impacts of climate change itself and sustainability of human settlements. advised that the sooner action is taken to to the responses adopted internationally Climate change is projected to have cut emissions, the less costly mitigation to address its impacts. Key vulnerabilities broad and significant environmental, will be to economies around the world. include: economic and social impacts in Australia. It is clear the world is now facing risks of • the hot, dry and naturally variable Understanding of Australia’s particular catastrophic, irreversible climate change. climate becoming hotter and drier over environmental vulnerability to climate Failure to act in time to reduce global much of the agricultural production change is developing but in its infancy. greenhouse gas emissions will represent zones and in the large population Key issues for Australia an implicit acknowledgement that this centres generation, particularly in developed Australia stands to be the developed • the fragility of Australia’s megadiverse countries, cannot afford to wear the costs country most affected by significant ecosystems and unique biota whose of mitigation for the welfare of the world, its climate change because of its hot, dry and evolutionary adaptation capabilities is ecosystems and future generations. highly variable climate. Small variations in likely to be exceeded within the short climate are more damaging to Australia There has been much deliberation. Time is timeframes involved than to many other developed countries. now running out for decisive action. •h igh variability of rainfall from year On a per capita basis, Australians to year, with increasing competitive Objectives pressures on available resources due emit more greenhouse gases to the atmosphere than any other country in •T o reduce Victoria’s greenhouse gas 4 to population growth and increased emissions towards achieving a stable Atmosphere the world apart from the United States of scarcity America. However its total contribution global climate •e xtreme drought, flooding and weather overall amounts to just 1.5% of global •T o reduce Victoria’s vulnerability through events and high risk of bushfires, all greenhouse gas emissions. 4.1 adaptive responses predicted to increase with climate Avoiding dangerous impacts of climate •T o foster further government and change change requires the world’s largest community response to address the • the particular sensitivity of temperate emitters (both developed and developing challenge of climate change in Victoria agriculture to climatic changes nations) to make deep cuts to their •d ependence on emissions-intensive greenhouse gas emissions. coal for electricity, with many energy The Garnaut Review Report points to intensive manufacturing industries in the Australia’s strong interest in taking economy mitigating action to lead the engagement •h igh transport energy requirements due of developing nations in an international both to Australia’s size and the legacy agreement and decisive action to of low density urban design mitigate climate change. The Report also states that Australia (and the world) •h igh population growth rate and has squandered much of the available concentration of settlements and time over the past 15 years to mitigate infrastructure along coastlines, exposed emissions and contain climate change to projected increase in the frequency impacts. and severity of extreme weather events • s ignificance of fossil fuels in Australia’s export trade and predominance of trade links with developing nations, especially in the Asia/Pacific regions • the vulnerability of many of our nearest neighbours, which are low-lying, island states subject to significant impacts from sea level rise and where adaptive capacity is relatively low. The UN has predicted there could be up 150 million ‘climate change refugees’ across the world by 2050. Photo: Jane Tovey | 194
Part 4 State of the Environment Atmosphere A1.1 The natural and enhanced greenhouse effect The natural greenhouse effect reduces the There are large natural year to year Since the industrial revolution around loss of heat by radiation from the Earth’s variations in climate. Natural climate 1750, the concentration of carbon dioxide surface, keeping the surface of the planet variability will influence actual warming has increased by one-third, methane warmer than it would otherwise be. This values in any single year or decade. has risen by 150% and nitrous oxide has is due to the presence in the atmosphere The global warming influence due to grown 18%. The increases in carbon of greenhouse gases, which absorb a increasing greenhouse gases is at global dioxide are due primarily to fossil fuel proportion of the heat before it is lost scales and cumulative over many years. use and land use change, while those of to space, and radiate some back to the At short time scales, natural variability methane and nitrous oxide are primarily surface (see Figure A1.1.). can offset that warming influence and due to agriculture. cause short term cooling. The long-term Naturally occurring greenhouse gases Globally, between 1970 and 2004, warming trend is unequivocal14. keep the planet warm enough to sustain greenhouse gas emissions covered by life. Without these gases, the planet’s The main greenhouse gases are water the Kyoto Protocol have increased by average temperature would be about 33°C vapour, carbon dioxide, methane and 70% (24% since 1990). Without additional colder - more like the moon. nitrous oxide. The Earth’s climate is policies, global greenhouse gas emissions also influenced by natural cycles, such are projected to increase by 25-90% by However, human activities, predominately as 100,000 year glacial cycles due to 2030, relative to 200016. the burning of fossil fuels, intensive 4&$5*0/$0-0634 wobbles in the Earth’s orbit, 11 year agriculture and land 1"350/& clearing, are causing 1"35580 1"355)3&& 1"35'063 1"35'*7& The global dependence on fossil fuels sunspot cycles and 2–7 year El Niño greenhouse gas concentrations to rise continues to increase rapidly. The cycles due to air-sea interactions. above natural levels, further heating populations and resource intensities the planet. This is called 1.4 1.4 the enhanced 1.4 1.4 1.4 Burning of fossil fuels, some forms of of developed nations are growing and greenhouse effect. As the concentrations agricultural activities and land clearing developing nations such as China and of these gases in the lower atmosphere /&653"-$0-0634 have contributed to high concentrations of India also now are emitting significant grows, global temperatures rise, causing carbon dioxide, methane and nitrous oxide levels of greenhouse gases as they changes to weather conditions worldwide. in the atmosphere. These anthropogenic continue their pathways of economic The enhanced greenhouse 1.4 1.4 effect 1.4 is often 1.4 emissions are considered very likely – growth and higher living standards. referred to as global warming or climate greater than 90% probability – to be the change. cause of most of the observed increase (3"1)4 in global average temperatures since the mid-20th century15. 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 Figure A1.1 The Greenhouse Effect Source: Department of Sustainability and Environment, 2006 The enhanced greenhouse effect Some solar radiation Some of the infrared radiation passes through is reflected by the earth the atmosphere, and some is absorbed and re-emitted and the atmosphere in all directions by greenhousegas molecules. The effect of this is to warm the earth’s surface and the lower atmosphere Solar radiation passes through the clear atmosphere Most radiation is absorbed Infrared radiation by the earth’s surface is emitted from and warms it the earth’s surface 195 | State of the Environment Report - Victoria 2008
Box A1.1 Greenhouse gases • nitrous oxide (N2O), which occurs which involves a range of processes with naturally in the environment, although different timescales. Around half the CO2 The main greenhouse gases generated human activities increase its atmospheric emitted is removed on a time-scale of 30 by human activity are: concentrations. This gas is most often years, a further 30% is removed within • carbon dioxide (CO2), which is the most released when chemical fertilisers and a few centuries, and the remaining 20% important anthropogenic greenhouse manure are used in agriculture. may stay in the atmosphere for thousands gas and is the main contributor to of years. Methane’s atmospheric lifetime Other greenhouse gases include some human-induced climate change. is about 8.4 years and nitrous oxide’s is manufactured gases such as sulfur Carbon dioxide accounts for about two around 114 years17. hexafluoride, chlorofluorocarbons (CFCs) thirds of greenhouse gases produced and some of their replacements. For purposes of measurement, all by human activities. The primary greenhouse gases are converted to a source of the increased atmospheric Water vapour is another particularly common unit, called CO2 equivalent concentration of carbon dioxide since important greenhouse gas. However, (CO2-e) and are measured in parts per the pre-industrial period results from direct human emissions of water vapour million (ppm). Parts per million (ppm) is fossil fuel use, with land-use change are negligible. Rather it is the response the ratio of the number of greenhouse providing another significant but of water vapour to atmospheric warming gas molecules to the total number of smaller contribution. Photosynthesis which dictates its importance for climate molecules of dry air. by plants removes CO2 from the change. A warmer atmosphere holds atmosphere. Before the industrial more water vapour, thereby increasing The best estimate of total CO2-e revolution, CO2 concentrations were greenhouse trapping and resulting in concentration in 2005 for all long-lived 4 typically around 280 ppm. By 2005, this further warming. This positive feedback greenhouse gases is about 455 ppm Atmosphere had risen to almost 379 ppm. therefore acts to amplify the warming CO2-e. However, the corresponding value initiated by increases in anthropogenic after the net effect of all anthropogenic • methane (CH4), which is not as greenhouse gases such as carbon forcing agents (including the effect of abundant as CO2, but is 21 times more 4.1 dioxide and methane cooling aerosols) are taken into account effective at trapping heat. It is released is 375 ppm CO2-e. It is the combined when vegetation decomposes in The greenhouse effect of these gases effect of all the influences on radiative oxygen-free environments (such as in occurs in the troposphere layer of the forcing and the consequent net CO2-e a fire or landfill), as well as from animal atmosphere where they are concentrated. concentration that is most relevant to the digestive processes. The lifetime of carbon dioxide in the consideration of changes to the climate atmosphere is difficult to quantify system18. 4&$5*0/$0-0634 because it is continuously cycled between 1"350/& 1"35580 1"355)3&& 1"35'063 1"35'*7& the atmosphere, ocean and biosphere, Greenhouse gases are generated through Table A1.1 Examples of economic activities generating greenhouse gases Source: Energy Information Administration (2005)19 a range of activities 1.4 including 1.4 1.4 agricultural 1.4 1.4 practices and industrial processes (see Carbon Dioxide Nitrous Oxide Methane Table A1.1). /&653"-$0-0634 Energy generation Agriculture soil Coal mining Figure A1.2 shows the long-term change management in the atmospheric concentration of Transport Transport Landfills carbon dioxide and1.4 methane1.4over the last Cement manufacture Sewage treatment Waste management 1.4 1.4 1000 years, (3"1)4 based on ice core analysis and direct atmospheric measurements, Metal production Landfills Rice cultivation including at Cape Grim in north west (e.g. aluminium, and other agriculture Tasmania. steel and iron) (e.g. cattle) 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 Figure A1.2 Atmospheric concentrations of carbon dioxide and methane over the last 1000 years (data from ice cores and Cape Grim) Source: CSIRO 2007 2,000 450 CH4 ppb CO2 ppm Carbon dioxide from Carbon dioxide recorded Antartic ice cores (left y axis) at Cape Grim(rigth y axis) 1,800 Methane from Antartic ice cores Methane recorded at Cape Grim 1,600 (left y axis) (rigth y axis) 400 1,400 1,200 1,000 350 800 CH4 600 300 400 CO2 200 0 250 1000 900 800 700 600 500 400 300 200 100 0 Years before present | 196
Part 4 State of the Environment Atmosphere The global growth rate in annual carbon Global climate change: A disturbing While CO2 concentrations, global mean dioxide emissions has increased from picture temperature and sea level rise have been 1.1% per year in the 1990s to more than The most recent scientific publications tracking at the upper end of the range of 3% per year between 2000 and 200420. paint a disturbing picture for the IPCC predictions, the ability of terrestial This is primarily due to increased fossil atmosphere and the climate. At the same and ocean sinks to remove carbon dioxide fuel use, but also to land-use change time it is becoming apparent that CO2 from the atmosphere is decreasing, (the main change being land clearing)21. concentrations, global mean temperature altering global carbon budgets28. These Further, agriculture has played a major role and sea level rise have been growing at a factors, coupled with an increasing global in the growth of nitrous oxide.22 faster rate than the highest of the range of CO2-e growth rate29, are likely to speed possible emission scenarios considered up climate change and exacerbate the Unlike other greenhouse gases, methane by the IPCC in 200125 (see Figure A1.3). impacts of climate change in the future. has stabilised in the last decade. After Therefore, it must be borne in mind that Natural climate variability will influence rapid growth of atmospheric methane the projected upper limits of warming actual warming values in any single year concentrations over the past 200 years, are conservative. There is a significant or decade30. the rate of growth has decreased since the early 1990s and the level has remained possibility that warming may occur in Observations of greenhouse gas relatively stable since 1999. The decrease excess of these values, particularly later in emissions indicate that current in the growth rate in the 1990s was due to the century, although the likelihood of this concentrations of carbon dioxide and a reduction in anthropogenic emissions23,i. occurrence is impossible to estimate at methane far exceed those at any time Although anthropogenic methane this stage26. in the last 650,000 years31. Over the last emissions have been rising again since In a paper published in Nature in 2008, century global surface temperatures the late 1990s, this increase is being offset Rosenzweig et al noted that27 “most of rose by 0.7°C and northern hemisphere by the drying of wetlands, caused by the observed increase in global average summers are, on average, 12.3 days draining and climate change, leading to temperatures since the mid-twentieth longer than at the beginning of the 20th reductions in natural methane emissions24. century is very likely to be due to the century. Glaciers have retreated, snow The overall effect has been a stabilising of observed increase in anthropogenic cover has decreased in most regions and methane concentrations since the turn of greenhouse gas concentrations, and Arctic sea-ice has reduced in thickness by the century. furthermore that it is likely that there has almost 50%. been significant anthropogenic warming Sea levels have risen by around 20 cm over the past 50 years averaged over over the last century (see Figure A1.4)and each continent except Antarctica, we the oceans have become more acidic32. conclude that anthropogenic climate More recently, a trend has been observed change is having a significant impact in relation to an increasing area of low on physical and biological systems biological productivity in the north and globally and in some continents”. Climate south Pacific and Atlantic oceans which change’s effects are not something to may also indicate that other changes are be considered only in the future, they are underway that were not entirely predicted already happening now. or understood33. Figure A1.3 Variations in the Earth’s surface temperature Year 1000 to Year 2100 Source: IPCC 2001 Departures in temperature in ºC (from the 1990 value) Global instrumental observations, Northern Hemisphere, proxy data observations 6.0 Projections 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 -0.5 -1.0 0 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 i Possible reasons for reduction in anthropogenic emissions include: the economic crisis in some OECD countries (not USA) between 1990 and 2000; fewer emissions from the oil and gas industry; and capture and better use of methane from landfills. 197 | State of the Environment Report - Victoria 2008
IPCC projections indicate that global sea absorb more solar radiation than before, Just like marine ecosystems, land-based level will likely rise by approximately 20 so adding to warming, which melts more ecosystems normally act as carbon sinks, to 60 cm (relative to 1990 levels) by 2100 ice and snow, and so on35. This is known taking carbon from the atmosphere and due to thermal expansion alone. However, as the Albedo effect. Indeed, the IPCC’s using it for growth. However, as these in the long term, the IPCC has warned of Fourth Assessment Report in 2007 notes ecosystems heat up, their balance is the potential sea-level rise associated with that as a result of the uncertainties of such altered. Plants become less and less contraction of the Greenland ice sheet and climate-carbon cycle feedbacks, the upper effective at taking in carbon dioxide37, the partial loss of polar ice sheets. This values of sea-level rise projections should while micro-organisms in the soil become melting of ice sheets in Antarctica and not be considered upper bounds for sea- more and more effective at putting it out, Greenland may add an extra 10 to 20 cm 4&$5*0/$0-0634 level rise. This contrasts with the IPCC causing the ecosystem as a whole to to this, bringing the1"35580 1"350/& total 1"355)3&& projected sea1"35'*7& 1"35'063 projections for global mean temperature go from being a carbon sink to being a level to somewhere between 20 cm and rises which include upper limits. carbon source. 80 cm34. Global climate models indicate In addition, the IPCC report notes that Melting of the Arctic permafrost threatens that mean sea level1.4 rise on the east coast current models indicate virtually complete to release vast quantities of carbon dioxide 1.4 1.4 1.4 1.4 of Australia may be greater than the global elimination of the Greenland ice sheet and and methane trapped in frozen vegetation. mean sea level rise. /&653"-$0-0634 a resulting contribution to sea-level rise of Recent research estimates that a major Such loss of polar ice is important as about 7 metres if global average warming melt of large tracts of the permafrost in white surfaces reflect more solar radiation were sustained for millennia in excess high latitudes of Russia, Canada, Alaska than dark surfaces, so as1.4 global1.4 warming of 1.9 to 4.6°C. It also notes that more and Scandanavia could release billions 4 1.4 1.4 melts ice and snow, it leaves behind rapid sea-level rise on century time-scales of tonnes of greenhouse gases. Release dark ocean or land; those surfaces then cannot be excluded. of even a fraction of the gases currently (3"1)4 Atmosphere trapped would dramatically accelerate climate change38. The risk is a feedback Figure A1.4 Global average sea level rise from 1870 to 2005 loop whereby increased greenhouse 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 Source: Church and White (2006); Holgate and Woodworth (2004); Leuliette et al. (2004) gases cause temperature rises that further 4.1 melt the permafrost and release even 25 Sea level (cm) Tide gauge observations (1870-2001) Tide gauge observations (1950-1999) more gases. Satellite altimeter observations The IPCC has indicated sea level rise may 20 occur far faster than the models have predicted as a result of such feedback loops. 15 Whilst climate change is unequivocal, major uncertainties in some impacts of climate change remain where climatic 10 feedback loops cannot be predicted accurately with current models. Ever more worrisome evidence, however, is 5 being found that climate feedback loops are more dangerous than previously considered. Long term potential impacts 0 on global thermohaline circulation, melting of the glacial permafrost, terrestrial uptake of carbon, the rate of ocean acidification -5 and the possibility of masking of climate 1870 1880 1900 1920 1940 1960 1980 2000 2010 change through anthropogenic emissions of aerosols are all examples of abrupt Year changes to the climate that may cause severe consequences to ecosystems Trend of melting of the Greenland ice sheet and human settlements. Further, as Source: Cooperative Institute for Research in Environmental Sciences (CIRES),University of Colorado36 noted by the IPCC, CSIRO and Bureau of Meteorology, the upper limits of warming projected to date tend to be conservative, and there is a significant possibility that warming and sea-level rise may occur in excess of projections, particularly later in the century39. | 198
Part 4 State of the Environment Atmosphere The complexity of the global climate system, incomplete understanding of Box A1.2 Key milestones in 1995 - IPCC Second Assessment Report the drivers of change to this system and the developing international “The balance of evidence suggests a our capacity to project future emissions scientific consensus on discernible human influence on global - plus the dependency of these on the sustainable development and climate.” effectiveness of international responses - climate change 1997 - Kyoto Protocol adopted - UN makes it profoundly difficult to accurately 1972 - The Limits to Growth: report agreement to reduce global greenhouse predict the consequences of climate detailing consequences of world’s rapid gas emissions by an average 5% on change on natural and human systems. population growth and use of finite 1990 levels; Australia a signatory but The risk inherent in this uncertainty is that resources does not ratify. predictions of the extremity and effects 1987 - Our Common Future: the 2001 - IPCC Third Assessment of climate change may dramatically Brundtland Report, alerted the world to Report “The Earth’s climate system underestimate the speed and scale of the urgency of making progress toward has demonstrably changed on both the changes. In order to counter the risk economic development that could be global and regional scales since the of extreme consequences, governments sustained without depleting natural pre-industrial era, with some of these must respond quickly and decisively to resources or harming the environment. changes attributable to human activities.” climate change. Due to the complexity and scale of changes required and the 1988 - The Intergovernmental Panel on 2005 - Kyoto Protocol comes into force. competing interests involved this has not Climate Change (IPCC) set up by the 2007 - IPCC Fourth Assessment Report occurred, to date. United Nations Environment Programme identifies unequivocal climate change; (UNEP) and the World Meteorological “Most of the observed increase in global The top 25 greenhouse emitting countries Organization to provide periodic average temperature since the mid 20th in the world together account for over assessments of published information on century is very likely due to the observed 87% of global emissions. While being climate change to decision-makers. increase in anthropogenic greenhouse responsible for only 1.5% of total global emissions40, Australia is the 14th largest 1989 - Montreal Protocol on Substances gas concentrations”; determined emitter of greenhouse gases in the world. That Deplete the Ozone Layer. emissions need to peak in 2015. On the emissions per capita scale of the 1990 - IPCC First Assessment Report. 2007 - The UNFCCC Bali Roadmap top 25 emitting countries (see Figure establishes a two-year process A1.5), Australia is the 2nd highest per 1992 - Earth Summit – UN Conference to develop a binding international capita41. In 2006, approximately one fifth on Environment and Development in Rio agreement for the post-Kyoto period de Janeiro. 4&$5*0/$0-0634 of these emissions came from Victoria42, (2013 onwards). which generated over 120 million tonnes 1"350/& 1"35580 1"355)3&& 1"35'063 1"35'*7& 1994 - The United Nations Framework of greenhouse gases. Between 1990 and 2007 - Australia ratifies the Kyoto Convention on Climate Change 2006, Victoria’s emissions grew by 12%43. Protocol. (UNFCCC) comes into force, 1.4 1.4 with the1.4 1.4 ultimate aim of stabilising atmospheric 2009 - Copenhagen IPCC/UNFCCC 1.4 Relative to other OECD countries, Australia’s high emissions are mainly the greenhouse gas concentrations at meeting to finalise the post Kyoto levels that would prevent dangerous (2013+) agreement on action to reduce /&653"-$0-0634 result of the high emissions intensity of energy use, rather than the high energy anthropogenic interference with the greenhouse gas emissions and the single intensity of the economy or exceptionally climate system. most important stage in determining high per capita income. Transport 1.4 1.4 1.4 1.4 whether the will to take action is present. emissions are not dissimilar to those of (3"1)4 other developed countries. Australia’s per capita agricultural emissions are among the highest in the world, especially Figure A1.5 Per capita greenhouse gas emissions of world’s 25 highest emitting countries 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 because of the large numbers of sheep Source: World Bank and cattle. The high emissions intensity of energy 25 Per capita emissions (t CO2e) use in Australia is mainly the result of our reliance on coal for electricity. The difference between Australia and other 20 countries is a recent phenomenon: the average emissions intensity of primary energy supply for Australia and OECD countrieswas similar in 197144. 15 10 5 0 Spain United States Australia Canada Netherlands Saudi Arabia Russia Kazakhstan Rep of Korea Japan UK South Africa Italy Ukraine Poland France Iran Mexico China Thailand Turkey Brazil Indonesia India Germany 199 | State of the Environment Report - Victoria 2008
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