Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...

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Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
Part 4
                1                              Introduction
                                               State of the Environment
                                               Atmosphere

         Atmosphere

187 |   State of the Environment Report - Victoria 2008
Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
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.

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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
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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.

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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

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Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
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.

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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
Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
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
Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
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
Atmosphere - Part 4 Atmosphere State of the Environment - Commissioner for Environmental Sustainability ...
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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