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Garnaut Climate Change Review
The impact of climate change and ocean acidification on the
Great Barrier Reef and its tourist industry
Prepared by
Ove Hoegh-Guldberg, Centre for Marine Studies, University of Queensland
Hans Hoegh-Guldberg, Economic Strategies Pty Ltd
June 2008
Contents
1
Aim of this paper ........................................................................................................................ 2
2
Background ................................................................................................................................ 3
3
The Great Barrier Reef Marine Park .......................................................................................... 4
4
Threats to the long-term sustainability of the Great Barrier Reef .............................................. 6
5
Global factors: climate change and ocean acidification............................................................. 7
6
Future changes to the Great Barrier Reef Marine Park as a result of climate change
and ocean acidification............................................................................................................. 10
7
Possible implications of climate change for tourism in Australia ............................................. 13
8
Implications of changes to the Great Barrier Reef................................................................... 14
9
Further implications of climate change for Australian tourism ................................................. 16
10
Australia in the world tourism market....................................................................................... 18
11
Consequences for Australian tourism ...................................................................................... 19
12
Potential responses and adaptation strategies of Great Barrier Reef tourism to
climate change ......................................................................................................................... 21
13
The need for further research .................................................................................................. 22
14
Conclusions.............................................................................................................................. 24
15
Acknowledgments .................................................................................................................... 25
16
References............................................................................................................................... 26
Appendix 1
Vulnerable tourist regions, Australia ........................................................................... 28
Appendix 2
Physical climate scenarios.......................................................................................... 33
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Aim of this paper
Climate change is the most significant environmental, economic and social issue of our time. It is also
one of the most supported scientific ideas, receiving the attention of thousands of scientists who have
defined it, argued for and against it, and have built up one of the most significant bodies of scientific
evidence ever established. Publication of the fourth assessment report by the Intergovernmental
Panel on Climate Change (IPCC) concluded in 2007: ‘Warming of the climate system is unequivocal’
and that ‘Most of the observed increase in globally averaged temperatures since the mid-20th century
is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.’ Climate
threatens a series of natural, economic and social systems, and if allowed to proceed unrestrained,
will lead to major changes in the way we lead our lives and conduct our business as a nation.
According to the fourth assessment report, coral reefs are among a series of ecosystems that are
highly threatened by rapid anthropogenic climate change. This paper summaries the current state of
knowledge about this threat to Australia’s Great Barrier Reef; the biological consequences and
resulting social and economic ramifications of these changes for Great Barrier Reef tourism, and by
extension Australian tourism generally. The Great Barrier Reef itself attracts an estimated $2 billionplus into the Australian economy, and has provided employment for over 60,000 Queenslanders. The
consequences of losing this magnificent ecosystem, and hence its iconic, social and economic
importance, are serious.
The aim of this study is to outline, summarise and discuss the issue of climate change for the Great
Barrier Reef and its highly productive tourism industry. Given the space available, this paper is not
intended as an exhaustive review of the science and economics of how climate change is likely to
affect the Great Barrier Reef and its associated industries. This is done in detail elsewhere (HoeghGuldberg 1999, Done et al. 2002, Hoegh-Guldberg and Hoegh-Guldberg 2003, Donner et al. 2005,
Hoegh-Guldberg et al. 2007). This article builds on this earlier work and uses the information gathered
to explore a range of scenarios for Queensland and the Australian economy as a result of mild to
severe impacts on the Great Barrier Reef. This article concludes with a discussion of future research
requirements for building an effective policy response to the challenges that climate change poses for
the Great Barrier Reef and its associated tourist industry.
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Background
Coral reefs line the coastline of hundreds of countries that are located between latitude 30°S and
latitude 30°N. Here, they build complex and biologically diverse ecosystems that form the basis for
tourism and fishing industries that provide in excess of $200 billion per annum as well as livelihood
from subsistence fishing to as many as 100 million people from these countries (Bryant et al. 1998).
Coral reefs require hard substrates in shallow waters (generally < 40 m) which have water
temperatures that remain above 18°C and carbonate ion concentrations of the least 200 µmol kg-1
(Kleypas et al. 1999). Coral reefs don’t do well close to rivers where the inundation of freshwater and
sediments will slow the growth of, or smother, corals. More recently, rivers have been found to exert
an even greater influence on the health of corals due to the fact that many now carry larger amounts
of sediments, nutrients and toxins due to the destabilisation of river catchment areas by increased
land-clearing and intensive coastal agriculture (McCulloch et al. 2003).
Corals are among the simplest multicellular animals and are related to anemones, jellyfish and
hydroids. They naturally lie at the heart of coral reefs. Not all corals build coral reefs. Those that build
the limestone-like frameworks of coral reefs, however, all form symbioses with tiny plant like
organisms known as dinoflagellates (‘zooxanthellae’; review, see Hoegh-Guldberg 1999). Symbiotic
dinoflagellates (which actually live inside the cells of their coral hosts) allow corals to capture sunlight
in large quantities and to grow rapidly in the shallow clear coastal waters typical of many tropical and
subtropical coastal areas. The abundant energy captured allows corals to lay down large amounts of
calcium carbonate (as aragonite) and build the enormous, three-dimensional structures that typify
coral reefs. These intricate and magnificent reef structures house over one million species (ReakaKudla 1996). In addition to housing a significant part of the ocean’s biodiversity, coral reefs also
provide a significant coastal barrier that protects other mangrove and sea grass ecosystems, which in
turn play important roles in providing habitat for a large number of key fisheries species. This
protection is also important to significant amounts of human infrastructure that line the world’s
coastlines including tropical and sub-tropical Australia.
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The Great Barrier Reef Marine Park
The Great Barrier Reef is one of the world’s most spectacular coral reef ecosystems. Lining almost
2,100 km of coastline, the Great Barrier Reef is the largest continuous coral reef ecosystem in the
world. It is home to an amazing variety of marine organisms including 6 species of marine turtles, 24
species of seabirds, over 30 species of marine mammals, 350 coral species, 4,000 species of
molluscs and 1,500 fish species. The total number of species number into the hundreds of thousands.
New species are described each year, and some estimates suggest perhaps we are only familiar with
less than 50% of the total number of species that live within this amazing ecosystem.
The Great Barrier Reef is also considered to be one of the most pristine ecosystems, which is a
consequence of a relatively low human population pressure (as compared to other regions like
Indonesia where hundreds of millions of people live directly adjacent to coral reefs) and a modern and
well-resourced management agency, the Great Barrier Reef Marine Park Authority, which practices
state-of-the-art, science-based environmental management. The Park was established in 1975 by the
Federal Government and was proclaimed a World Heritage Area in 1981.
Since 1975, the Great Barrier Reef Marine Park has existed as a multi-use park system, involving a
patchwork of managed areas across its 375,000 square kilometres that range from areas that are
completely open to commercial and recreational fishing (‘blue zones’) to areas that are closed to all
activities (‘green zones’). Up until recently, only 4.6% of the Great Barrier Reef Marine Park was
designated as falling within ‘green’ zones. In 2003, however, after an exhaustive information gathering
and redesign process (Representative Areas Program or RAP, GBRMPA 2008a), the Australian
Federal Parliament passed legislation that rezoned the Great Barrier Reef Marine Park so that over
33% of the Park is now designed as green no-take zones. This change occurred in response to a
vastly improved knowledge of the Great Barrier Reef (after almost three decades of research) and
growing evidence of deterioration of some areas of the Park under the influence of range of pressures
arising from human activities.
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Figure 1
Map of the Great Barrier Reef Marine Park (courtesy of GBRMPA)
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Threats to the long-term sustainability of the Great Barrier Reef
Coral reefs like the Great Barrier Reef are threatened by both local (e.g. water quality, coastal
degradation, pollution and fishing pressure) and global (e.g. global warming, ocean acidification)
stressors. These two categories of stress are distinguished in terms of whether particular stresses
acting on a coral reef arise from ‘local’ sources such as a fishing industry, or from ‘global’ changes to
the earth’s atmosphere and climate. Both local and global factors have already had major impacts on
coral reefs. For example, the over-exploitation of coral reef species in many countries has led to the
major decline in key fish species on coral reefs (e.g. herbivorous fish) which have led in turn to major
changes in the ecological structure of coral reefs. The major decline of reef-building corals on
Caribbean reefs over the past 40 years (from >60% in 1970 to less than 10% coral cover today;
Hughes 1995) has been mainly attributed to the removal of herbivorous fish by over-populated coastal
regions. Because herbivorous fish are important in the maintenance of the ecological balance
between seaweeds and corals, their removal is considered as the prime reason why Caribbean coral
reefs have became overgrown by seaweeds and lost their dominant communities of corals (Hughes
1995; Jackson et al. 2001).
While overexploitation has affected some parts of the Great Barrier Reef, there is a general
perception that the main threats to the Great Barrier Reef stem more from reduced water quality (i.e.
increased nutrients and sediments) as a result of agricultural activities in coastal Queensland as
opposed to the fishing of herbivorous species (which does not occur to any real extent). Agricultural
activities have resulted in a tenfold increase in the flux of sediments (and probably nutrients) down the
rivers of Queensland starting soon after the arrival of European farmers, hard-hoofed cattle and
coastal agriculture (McCulloch et al. 2003). The increased nutrient and sediment levels flowing out of
these disturbed river catchments and coastal areas is most likely to have driven some of the loss of
inshore Great Barrier Reef coral reefs (i.e. first 1–5 km of coastal reef system). One of the most
graphic illustrations of the slow and insidious changes in the condition of corals along the Queensland
coastline is the comparison of photos taken 100 years with those taken of the same area today
(Wachenfeld 1997). In most cases, these paired photographs reveal that rich coral-dominated
communities were once common along the coast of Queensland whereas today they are not.
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Global factors: climate change and ocean acidification
Changes to the greenhouse gas content (principally CO2 and methane) have driven changes to the
average temperature of the planet, which have in turn driven changes to the temperature of the upper
layers of the ocean. The upper layers of the ocean are now 0.7°C warmer than they were was 100
years ago. As a result, the Great Barrier Reef waters are 0.4°C warmer than they were 30 years ago
(Lough 2007). Increasing atmospheric carbon dioxide has also resulted in 0.1 pH decrease (i.e. the
ocean has become more acidic) which has removed 30–40 μmol kg-1 carbonate ions from ocean
bodies like the coral sea that normally contain between 250–300 μmol kg-1 (Hoegh-Guldberg et al
2007). In addition to the size of the absolute change, global conditions have varied at unprecedented
rates of change. Changes in atmospheric carbon dioxide (hence carbonate ion concentrations) and
sea temperature has increased at rates that are 2–3 orders of magnitude faster than the majority of
changes that have occurred over the past 420,000 years at least (see Table 1 in Hoegh-Guldberg et
al. 2007, Science, Dec 2007).
These changes in the conditions surrounding coral reefs have already had major impacts on coral
reefs. Short periods of warm sea temperature, once probably harmless but now building on the higher
sea temperatures due to climate change, have pushed corals and their dinoflagellate symbionts
above their thermal tolerance. This has resulted in episodes of mass coral bleaching that have
increased in frequency and intensity since they were first reported in the scientific literature in 1979
(see reviews by Brown 1997, Hoegh-Guldberg 1999, Hoegh-Guldberg et al. 2007). Coral bleaching
(Fig. 2) occurs when the symbiosis between corals and their critically important dinoflagellate
symbionts breaks down. This can occur for a number of reasons, one of which is heat stress. The
result of the breakdown of the symbiosis is that the brown dinoflagellate symbionts leave the
otherwise translucent coral tissue, leaving corals to remain as a stark white colour (hence, ‘bleached’).
In 1998, most coral reefs worldwide experienced mass coral bleaching over a 12 month period that
began in the eastern Pacific in December 1997. While many coral reef communities recovered from
the subsequent 12 month period of extremely warm sea temperatures (driven by an unusually strong
El Niño disturbance on top of the steadily rising sea temperatures globally), many coral reefs such as
those in the Western Indian Ocean, Okinawa, Palau and Northwest Australia were devastated by
bleaching and the subsequent mass mortality event. In these cases, coral bleaching was followed by
mass mortalities that removed over 90% of the resident corals on these reef systems. At the end of
the 12 month period, bleaching across the globe had removed an estimated 16% of the world’s coral
(Hoegh-Guldberg 1999). Whereas some of these reefs have started to recover, recovery has been
exceedingly slow and coral cover does not resemble that seen on these reefs prior to 1998 (Wilkerson
2004).
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Figure 2
A. Coral reef after experiencing mass coral bleaching (Great Keppel Island, southern Great Barrier Reef). B.
Close-up of bleached coral showing intact but translucent tissues over the white skeleton. Photos by O. HoeghGuldberg
A.
B.
The Great Barrier Reef has been affected by coral bleaching as a result of heat stress six times over
the past 25 years. Recent episodes on the Great Barrier Reef have been the most intense and
widespread. In 1998, the Great Barrier Reef experienced what was considered at the time as its worst
case of mass coral bleaching. In this event over 50% of the coral reefs within the Great Barrier Reef
Marine Park were affected. This was followed, however, by an even larger event in 2002 which
affected over 60% of the reefs with the Great Barrier Reef Marine Park. Fortunately in both cases,
only 5–10% of corals affected by coral bleaching died, which was far less than the mortalities seen in
regions such as the Western Indian Ocean or Northwest Australia (ranging up to 46%; HoeghGuldberg 1999). It is significant that coral bleaching is now considered ‘to pose the greatest long-term
risks to the Great Barrier Reef’ (GBRMPA 2008b).
The changes in the water chemistry that have arisen as a result of ocean acidification, is adding
additional pressure on coral reefs. Increasing concentrations of atmospheric carbon dioxide is
entering the ocean in ever-increasing amounts. Once in the ocean, carbon dioxide combines with
water to produce a weak acid, carbonic acid, which subsequently converts carbonate ions into
bicarbonate ions. This leads to a decrease in the concentration of carbonate ions, which ultimately
limits the rate of marine calcification (Figure 3). A recent study has found a 20% decrease in the
growth of corals on the Great Barrier Reef (Cooper et al. 2008), which appears to be a direct result of
the changing conditions. While we are just starting to understand the impacts of ocean acidification on
the Great Barrier Reef, there is consensus that the rate of change in the acidity of the ocean poses as
great a threat to coral reefs as does global warming (Raven et al. 2005; Hoegh-Guldberg et al. 2007).
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Figure 3
Schematic diagram showing the link between atmospheric carbon dioxide, ocean acidity and the calcification
rates of coral reefs and other ecosystems. Insert diagram depicts relationship between atmospheric carbon
dioxide (CO2 atm) and ocean carbonate concentrations. (Reprinted courtesy of Science Magazine)
Ocean Acidification
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Future changes to the Great Barrier Reef Marine Park as a result of
climate change and ocean acidification
Climate change and ocean acidification are placing coral reefs in conditions that they have not
experienced over the past 740,000 years, if not 20 million years (Raven et al 2004; Hoegh-Guldberg
et al 2007). These changes are occurring at rates which dwarf even the most rapid changes seen
over the past million years. Even the relatively rapid changes during the ice age transitions, which
resulted in major changes in the biota of the planet, occurred at rates of change in carbon dioxide and
temperature which were at least two orders of magnitude (i.e. one hundred times) slower than the rate
of change that has occurred over the past 150 years. Most evidence suggests that this rate of change
exceeds the biological capacity of coral reefs to respond via genetic change (evolution). As a result,
there is a high degree of consensus within scientific circles that coral reefs, like a large number of
other ecosystems, are set to change rapidly over the coming decades (IPCC 2007, Done et al. 2003).
Consideration has recently been given to how reef systems like the Great Barrier Reef will change in
response to changes in atmospheric gas composition. In this regard, a recent paper (Hoegh-Guldberg
et al. 2007) concluded that carbonate coral reefs such as the Great Barrier Reef are unlikely to
maintain themselves beyond atmospheric carbon dioxide concentrations of 450 ppm. Neither
temperature (+2°C above pre-industrial global temperatures) nor ocean carbonate concentration
-1
(<200 μmol kg ) in these scenarios are suitable for coral growth and survival, or the maintenance of
calcium carbonate reef structures. These conclusions are based on the observation of how coral reefs
behave today and how they have responded to the relatively mild changes in ocean temperature so
far. Mass coral bleaching, for example, is triggered at temperatures that are 1°C above the long-term
summer maxima. Coral reefs also do not accrete calcium carbonate or form limestone-like coral reefs
in water that has less than 200 µmol kg-1 carbonate ion concentrations (roughly equivalent to an
aragonite saturation of 3.25). These conditions will dominate tropical oceans if carbon dioxide
concentrations exceed 450 ppm (Fig. 4).
Taking the two drivers together allows a projection of how the condition of Great Barrier Reef will
change if atmospheric concentrations of carbon dioxide continue to grow. In terms of the reference
scenarios for this review, the critical point for carbonate coral reef systems like the Great Barrier Reef
arise when carbon dioxide concentrations exceed 450 ppm. Using the evidence and conclusions of
the Hoegh-Guldberg et al. (2007) study, in turn based on previous studies (Hoegh-Guldberg 1999,
Donner et al. 2003, Hoegh-Guldberg and Hoegh-Guldberg 2003), three basic scenarios for the Great
Barrier Reef can be assigned (Figure 5).
It is important that the three scenarios in Figure 5 be seen as representing a continuum of change and
not a set of discrete thresholds or ‘tipping points’. That said, it is also noteworthy that coral reefs
regularly show non-linear behaviour (i.e. minimal change for a period and then a sudden and
catastrophic decline in once dominant species as an environmental variable changes) and, hence,
while we don’t know where these ‘breakpoints’ exist relative to particular concentrations of
atmospheric carbon dioxide, it is crucial to understand that there is a significant likelihood that
ecosystems like the Great Barrier Reef might experience phase-transitions such as those already
seen in the Caribbean and other coral reef realms (Hughes 1995).
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Figure 4
Calculated values for aragonite saturation, which is a measure of the ease with which calcium carbonate crystals
(aragonite) form, as a function of geography. Coral reefs today only form where the aragonite saturation exceeds
3.25, which is illustrated by the blue coloured areas (coral reefs found today are indicated in this panel by the
pink dots). As the concentration of carbon dioxide in the atmosphere increases from 383 ppm today, the extent
of conditions that are suitable for the formation of carbon coral reefs dwindles until there are few areas with
these conditions left at 550 ppm and above. Ocean acidification represents a serious threat to carbonate reef
systems and may see the loss and decay of reef structures across the entire tropical region of the world
(Reprinted courtesy of Science Magazine; Hoegh-Guldberg et al. 2007).
In the case of minimal climate change (scenario C) atmospheric carbon dioxide stabilises at 420 ppm.
In this case, conditions surrounding the Great Barrier Reef will largely resemble those of today with
the following important differences. Firstly, mass coral bleaching events are likely to be more frequent
and intense relative to those that have occurred over the past 25 years. Based on modelling studies
(Hoegh-Guldberg 1999, Done et al. 2002, Donner et al 2003), mass coral bleaching events are likely
to be twice as frequent as they are today if sea temperatures surrounding the Great Barrier Reef
increase another 0.55°C over and above today’s temperatures. Changes in the sea temperature of
this magnitude will also increase the intensity of the thermal anomalies which, depending on the
particular phase of the El Niño Southern Oscillation and longer term changes in sea temperature such
as the Pacific Decadal Oscillation (PDO), will result in large scale impacts on coral reefs like the Great
Barrier Reef. This will result in a greater likelihood of mass mortalities among coral communities, and
an overall downward adjustment of average coral cover on coral reefs like those in the Great Barrier
Reef Marine Park (Hoegh-Guldberg et al. 2007). Some areas may lose coral permanently while
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others, such as those in well flushed and ecologically resilient locations (e.g. with good water quality,
intact fish populations), are likely to remain coral dominated.
Secondly, there is likely to be a shift towards reduced three-dimensional reef frameworks as
concentrations of carbonate ions decrease and become limiting for the calcifying activities of corals.
This may remove the habitat for some species (e.g. coral-dwelling fish and invertebrate species) while
it may increase habitat for others (e.g. some herbivorous fish species). It is important to appreciate
that reefs are likely to be populated by some form of marine life. Equally importantly, the replacement
organisms are unlikely to match (replace) the beautiful and charismatic coral reefs that we currently
enjoy.
The importance of marine parks in protecting and maintaining conditions for coral reefs would
increase in importance in Scenarios B and C (Appendix 2). Several studies have shown that the
recovery of coral reefs (and hence their long-term sustainability) after climate change disturbances
such as coral bleaching events is faster if the affected reef is protected from local stresses like poor
water quality and over exploitation of herbivorous fish (Hughes et al. 2003, Hughes et al. 2007).
If atmospheric CO2 increases beyond 450 ppm, large-scale changes to coral reefs would be
inevitable. Under these conditions, reef-building corals would be unable to keep pace with the rate of
physical and biological erosion, and coral reefs would slowly shift towards non-carbonate reef
ecosystems. Reef ecosystems at this point would resemble a mixed assemblage of fleshy seaweed,
soft corals and other non-calcifying organisms, with reef-building corals being much less abundant
(even rare). As a result, the three-dimensional structure of coral reefs would slowly crumble and
disappear. Depending on the influence of other factors such as the intensity of storms, this process
may happen at either slow or rapid rates. It is significant to note that this has happened relatively
quickly (over of an estimated 30 to 50 years) on some inshore Great Barrier Reef sites.
The loss of the three-dimensional structure has significant implications for other coral reef dwelling
species such as fish populations where an estimated 50% of the fish species are likely to disappear
with the loss of the reef-building corals and the calcium carbonate framework of coral reefs (Munday
et al. 2007). Loss of the calcium carbonate framework would also have implications for the protection
provided by coral reefs to other ecosystems (e.g. mangroves and sea grasses) and human
infrastructure, as well as industries such as tourism which depends on highly by diverse and beautiful
ecosystems. While coral reefs under this scenario would retain considerable biodiversity, their
appearance would be vastly different to the coral reefs that attract tourists today (Fig 5B).
If CO2 atm exceeds 500 ppm and conditions approach those of scenario A (as well as scenarios R1
and R2), conditions will exceed those required for the majority of coral reefs across the planet (Fig 4).
Under these conditions, the three-dimensional structure of coral reef ecosystems like the Great
Barrier Reef would be expected to deteriorate, with a massive loss of biodiversity and ecological
function. Many of the concerns raised in a recent vulnerability assessment (Johnson and Marshall
2007) would become a reality, and most groups on the Great Barrier Reef would undergo major
change. As argued by many other coral reef scientists (e.g. Hoegh-Guldberg et al. 2007; IPCC 2007),
the increase in atmospheric carbon dioxide 500 ppm (expected under scenario A, R1 and R2) would
result in scenarios where any semblance of reefs to the coral reefs of the Great Barrier Reef Marine
Park today would vanish. The net effect of losing the structure and biodiversity of the Great Barrier
Reef on tourism is likely to be significant at this point. These scenarios and their impact on one of
Australia’s most productive industries are discussed in the next sections of this paper.
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Possible implications of climate change for tourism in Australia
The next sections will analyse the implications of changes to the Great Barrier Reef and will then
proceed to consider possible implications for total Australian tourism under climate change. Loss of
tourism income to the Great Barrier Reef regions does not equal loss of tourism income for Australia,
because some of the tourism dollar will be spent elsewhere in the country, and Australian tourists may
become less inclined to travel overseas. Based on an analysis of all Australia’s tourism regions, we
will discuss the total impact of climate change on tourism in these other regions, and will consider
(qualitatively) how much of tourism lost to the coastal regions along the Great Barrier Reef may be
diverted to other parts of Australia. Based on a recent report for the October 2007 Davos conference
on climate change and tourism (WTO et al. 2007), we conclude with an analysis of world tourism
under climate change to provide a perspective on Australia’s competitive position in the international
tourism market, including the likely competitive position of the Great Barrier Reef.
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Implications of changes to the Great Barrier Reef
In 1998–99, the value of tourism as a contribution to total gross regional product in the five regions
adjacent to the Great Barrier Reef was about $2.0 billion (in 2000–01 prices). This compared with a
total tourism GDP of $6.3 billion for Queensland. (Hoegh-Guldberg and Hoegh-Guldberg 2003).
The tourism satellite accounts for Australia for 2005–06 amounted to 3.9% of total GDP, or $37.6
billion (ABS 2007). Recent accommodation statistics for Queensland amount to about 28% of
Australia. This suggests that tourism’s contribution to Queensland’s Gross State Product in 2005–06
was about $10.5 billion, in prices applying to that year. It could be slightly higher, reflecting a greater
ratio of holiday makers to total visitors in Queensland than in other states.
The research into the economic value of tourism in the regions along the Great Barrier Reef (HoeghGuldberg and Hoegh-Guldberg 2003) benefited from a unique compilation of regional statistics
showing the contribution of tourism to each Queensland region (OESR 2002). Tourism, of course, is
not the only industry that contributes to the economic product of these regions through exports.
Prominent primary industries include beef, sugar, horticulture and fisheries, and there are strong
contributions from coal mining from the Mackay hinterland, bauxite from Weipa and aluminium
smelting in Gladstone.
Tourism is, however, an integral part of these regional economics. Its share of total regional economic
product (which includes the local industries generated by exports from the regions) amounted to 7.1%
for the five regions in 1998–99. Its contribution to the Far (‘Tropical’) North Queensland region was
double that (14.4%), compared with 5.1% in the Northern region around Townsville, 6.1% in Mackay,
3.6% in Fitzroy, and 5.9% in Wide Bay-Burnett. Employment in tourism in the five regions was even
higher relative to total employment in these regions, at 10% (16.3% in Far North Queensland),
reflecting the labour-intensive nature of tourism.
Figure 5
Projected changes to tropical reef ecosystems as a result of global warming and ocean acidification
A. Reference scenario C
B. Reference scenario B
C. Reference scenariosA, R1 and R2
A. If atmospheric carbon dioxide levels stabilise at 420 ppm (reference scenario C), conditions will be similar to today except that mass bleaching events
will be twice as common and will be more severe on reefs like the Great Barrier Reef. B. Atmospheric carbon dioxide concentrations that increase to
around 450 ppm, together with a global temperature rise of 1°C above today, a major decline in reef-building corals is expected (reference scenario B).
Because carbonate ion concentrations will fall below that required by corals to calcify and keep up with the erosion of calcium carbonate reef frameworks,
reef frameworks will increasingly erode and fall apart. Seaweeds, soft corals and other benthic organisms will replace reef building corals as the dominant
organism on these much simpler reef systems. C. Greater levels of carbon dioxide build up in the atmosphere, and associated temperature change
(reference scenarios A, R1 and R2) will be catastrophic for coral reefs which will no longer be dominated by corals or many of the organisms that we
recognize today. Reef frameworks will active deteriorate at this point, with ramifications for marine biodiversity, coastal protection and tourism.
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Not all the tourism in these regions is related to the existence of a relatively pristine reef. Some people
are business visitors, others come to see friends and relatives rather than the reef, and some holidaymakers don’t come to experience the reef. It was important to estimate the proportion of total tourism
generated by an interest in the reef as such. A James Cook University paper using principal
components analysis (Pearce et al. 1997), though dated, provided the best clue. It allowed an
estimate to be made (Hoegh-Guldberg and Hoegh-Guldberg 2003) that 62% of total visitor nights
represented reef-interested tourism, with the highest proportions in the two main ‘tourism hubs’ of
Tropical North Queensland (90%) and the Whitsundays (72%). The highest observation in the rest of
the regions along the reef was for the Northern region around Townsville (65%), followed by Fitzroy
which include the main centres of Rockhampton and Gladstone (55%), Mackay region other than the
Whitsundays which is a separate tourist region (43%), and Wide Bay-Burnett at the southern border of
the reef (23%). These figures make sense in relation to the known distribution of reef areas and tourist
resorts.
The proportion of estimated reef-interested tourism differs depending on the origin of visitors. In the
total area, 43% of intrastate visitor nights were associated with interest in the reef, compared with
69% for interstate and 82% for inbound visitors. In Tropical North Queensland, the proportions were
79% for intrastate, 92% for interstate and 93% for inbound visitors. In the Northern region, the
proportions were 59%, 69% and 81%, respectively, and in the Whitsundays, 58%, 78%, and 75%
(Hoegh-Guldberg and Hoegh-Guldberg 2003). Clearly, these regions are sensitive to the effects of
climate change, especially Tropical North Queensland. In addition, this region showed the strongest
growth rate among all the regions according to the available evidence, and therefore has the furthest
to fall given the advent of adverse conditions.
In summary, the dependence of the tourism industry on a healthy Great Barrier Reef is enormous.
Given that the total annual value of tourism to the Queensland economy is in the order of $10 billion,
and the share of the reef regions close to one-third of the total value, the reef-interested tourism
economy most at risk is in excess of $2 billion in current dollars. The Tropical North Queensland
region accounts for about 45% of this figure, close to $1 billion.
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Further implications of climate change for Australian tourism
Especially in an international perspective, Northern Queensland and the Great Barrier Reef loom
largest among Australia’s tourism regions, but the area is rich in other natural attractions, above all
Tropical North Queensland. Australia’s role as a tourism magnet and how this could be affected by
climate change is the subject of the next sections.
Coral reefs are only one category of tourist attractions that could be affected by climate change. The
full list of such attractions includes coral reefs; mountains, snow and alpine ecosystems; rainforests
and other national parks; native flora; wetlands; mangroves; whale watching; recreational fishing;
beaches; and vineyards (there are others as well but these would account for the vast bulk of
vulnerable tourist activities). Some of these may appear to be supplementary rather than major
attractions, but they all have their own characteristic features and particular strengths in individual
tourist regions in Australia. An analysis of the prospective risks associated with each feature, and their
combined impact in each of 77 Australian tourism regions, can be found in Hoegh-Guldberg (2008).
Appendix 1 is taken from that paper.
The analysis also identifies and incorporates five major deterrents working against the positive
attractions of a particular region under conditions of climate change. They are salinity, bushfires,
ultraviolet radiation, urban heat, and disease and accidents. Each region was rated on each of these
fifteen factors (ten groups of attractions and five deterrents) on a scale from five (extreme potential
exposure) to nil (no significant exposure). The approach, while subjective and explorative in nature,
went a considerable way towards identifying the most vulnerable features of the Australian industry in
conditions of climate change. Among the 77 tourism regions, it identified the following five as the most
threatened (see Appendix 1 for detail):
•
Tropical North Queensland, the hub of Great Barrier Reef tourism, in addition to the coral reef
contains severely threatened rainforest areas, beaches in danger of inundation and increasing
storm damage, and threats to fishing and from bushfires and ultraviolet radiation. The region
emerges as by far the most threatened in Australia. The threat to the region is exacerbated by a
high reliance on international holiday tourism, liable to be relatively easily diverted elsewhere, and
currently accounting for more than 50% of total holiday tourist bed nights.
•
Southwest Western Australia is the scene of Australia’s sole biodiversity hotspot, one of only
twenty-five in the world. It has high risk ratings based on national parks, the greatest diversity of
vulnerable native flora, a strong but vulnerable wine industry, and together with the MurrayDarling Basin, the greatest salinity problem in the country. It attracts a large number of holiday
tourists, but not many are international visitors.
•
The Top End of the Northern Territory is at risk for its national parks, wetlands, increased
ultraviolet radiation, urban heat, and disease. It also attracts many holiday tourists, and more than
one-fifth of bed nights represents inbound holiday visitors.
•
The region centred on Townsville is at comparatively high risk mainly due to its national parks
and rainforests, its recreational fishing, and increased ultraviolet exposure, as well as being
situated along the Great Barrier Reef. It attracts a moderate number of holiday tourists (nowhere
near the number going to Tropical North Queensland), of whom slightly more than one-fifth on a
total bed night basis represents international visitors.
•
The fifth region most at risk is Gascoyne alongside the Western Australian coral coast (Ningaloo
Reef). While having other strengths in the tourist industry, the main one under threat is the reef,
which has been rated increasingly at risk in reviews of environmental health over the past five
years (Hoegh-Guldberg 2008). Tourism to date has been fairly modest, especially from overseas.
While referring to Hoegh-Guldberg (2008) for a full description of this analysis, and Appendix 1 for
numerical detail, the following observations apply to threats on a state-by-state basis:
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Queensland is most at risk in terms of absolute number of tourist nights, especially the Tropical North.
Western Australia has the largest number of regions at relatively high risk for a variety of reasons, and
its tourist industry is rated relatively most vulnerable to climate change. The Top End of the Northern
Territory is also rated at high risk; other parts of the Territory less so.
New South Wales is rated at moderate risk (except its northern regions), and the southern states of
Victoria, South Australia and Tasmania at least risk overall. This does not mean that these states or
even any individual region within them are without risk. It is impossible to identify one part of Australia
that is.
Figure 6
Most at-risk tourism destinations for mid to late 21st century*
Figure 6: Most-at-risk tourism destinations for mid to late 21st century*
North Carib- South Northern MediterAmerica bean America Europe ranian Africa
Middle Southeast Indian Pacific Australia/
East
Asia Ocean** Ocean** NZ
Defined as hotspot
Warmer summers
Warmer winters
Increase in extreme events
Sea level rise
Land biodiversity loss
Marine biodiversity loss
Water scarcity
Political destabilisation
Increase in disease outbreaks
Travel cost increase***
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* Key destination vulnerabilities are identified at sub-regional level in full technical report (not yet released as at mid-January 2008)
** Small island nations
*** From mitigation policy
Source: UN World Tourism Organization, UN Environment Program and World Meterological Organization, Climate Change and Tourism:
Responding to global challenges. Advanced summary October 2007. Background information for the Second International Conference on
Climate Change and Tourism, Davos, Switzerland 1-3 October 2007
Figure 6. The Davos conference on climate change and tourism in October 2007 concluded that of the
world’s ten major tourism regions five were defined as ‘hotspots’, especially threatened. These include
Australia and New Zealand and the neighbouring regions of small-island nations in the Indian and
Pacific Oceans. Each region was rated according to the direct and indirect impacts of climate change
listed in the left-hand column. Only one other region, the Caribbean, equals Australia and New
Zealand in being threatened by eight of the ten criteria. The full Davos background paper, when
available, will show assessments by subregions.
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10
Australia in the world tourism market
The second international conference on climate change and tourism in Davos in 2007 made further
progress towards defining tourist industry competitiveness in the advent of significant climate change.
The summary of its report on the subject (WTO et al. 2007) identified ten criteria setting out the
disadvantages of each of ten regions of the world. Furthermore, it designated five of these regions as
‘hotspots’ at particular risk. These regions were the Caribbean, Mediterranean, small island nations in
the Indian Ocean, small island nations in the Pacific, and Australia/New Zealand. This is a dire
warning. Figure 6 shows that Australia scored weaknesses on eight of ten criteria. Land biodiversity
loss and political destabilisation were the only criteria not rated as special weaknesses.
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Consequences for Australian tourism
The fossil-intensive climate change scenario A1FI with rapid economic growth, a world population
peaking around 2050 and rapid technological change may be regarded as close to worst-case, when
considered without any mitigation policies. This has consequences for all Australian tourism but
especially for the Tropical North the site of a great amount of holiday tourism, a large percentage of
which is from overseas.
This assessment must be prefaced by two considerations: the world depicted by the A1FI scenario
will grow rapidly which, other things being equal, should benefit total tourism industry growth, and the
tourism industry is renowned for its resilience and adaptability. So we are discussing what might be
tourism patterns under a scenario causing great environmental damage to our most sensitive natural
resources and ecosystems, and putting great constraints on long-haul air travel, compared with what
might have been in the absence of climate change.
We need to move from global analysis of tourism patterns which defines Australia as part of the most
vulnerable hotspots in the world, toward regional analysis of future tourism patterns within Australia,
before drawing the consequences for the Great Barrier Reef. This analysis is by necessity qualitative
rather than based on economic modelling, which in any case would have to be very complex.
This paper concentrates on the part of total tourism that is holiday-related, and which may be
expected to be particularly influenced by deteriorating tourist attractions. Business tourism may be
influenced for reasons such as remote meeting arrangements compensating for increasingly
expensive air travel as fuel prices rise. Visiting friends and relatives is also comparatively unaffected
by the state of the tourist attractions but like business tourism may be discouraged from long-distance
air and ground travel by rising fuel prices.
The project specification for this paper sets no date for the perspective to be adopted, other than
specifying an increase in mean temperature at 4.5°C by 2100 in the reference scenarios R1 and R2.
Obviously things will get worse as the century progresses, in the absence of mitigating action. This
applies whether a wet or dry climate is postulated for Australia, though these variants of the A1FI
scenario will have different effects on different regions. In a qualitative way, we are applying a medium
to long term focus in our comments, say up to 2050.
World tourism patterns: Australia viewed as a total destination will suffer as an international tourism
destination due to a combination of the local factors highlighted in Figure 6, of which the most crucial,
at least in the dry variant, may well be water scarcity. The impact will be aggravated by the last item
on the list: travel cost increase. Australia, according to this, is destined to lose market share of
international tourism.
Tourism within Australia: Generally speaking, Western Australia will be relatively most vulnerable
over the coming decades, especially under the dry version of the A1FI world. Southwest Western
Australia is particularly vulnerable, and Gascoyne along the Ningaloo Reef almost as much. The main
vulnerabilities of Queensland are in the north, while high-level tourism areas such as the Gold and
Sunshine Coasts may retain some relative advantages despite risks of sea level rises, storm surges
and rising summer temperatures.
Generally, the relatively advantaged areas are to the south (Victoria, South Australia, Tasmania). One
would expect the disadvantages, especially the loss or damage of natural ecosystems, to cause a
shift from the north to the south, and as far as international tourism is concerned, from Australia to
destinations elsewhere, with the impact of deteriorating natural attractions to be exacerbated by a
global ‘tyranny of distance’, with tourists travelling shorter distances. On the other hand, relatively
more Australians may travel domestically rather than going overseas.
Great Barrier Reef: As the most vulnerable of all Australian regions, and with a high inbound tourism
component, the tropical north would be relatively badly affected. Twenty or thirty years out, most
factors will be militating against further growth, despite the resilience of the tourist industry which will
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manifest itself in experimenting with other attractions, not necessarily associated with the reef,
rainforests and the region’s other current attractions. Areas further south along the reef will be less
disadvantaged, since they are already relatively less attracted by the reef itself.
It remains to be said that we have assumed that the A1FI world will indeed see strong economic
expansion, with currently less developed countries catching up with the current ‘first world’—the
current situation in China and India writ large and global. The big question is whether this is realistic or
whether we are in for some rude shocks if we don’t start to mitigate the effects today. Could A1FI go
badly wrong and the world could stop expanding due to a badly mismanaged global energy policy?
What risks do we face? The Stern Report (2006) on the economics of climate change hinted at such
risks in its economic analysis of climate change.
In comparison with the A1FI scenario, sufficient mitigation to arrive at the modest projections of +1°C
by 2100 will have beneficial effects on the most threatened natural resources such as Australia’s two
major coral reefs, mountain snow, the biodiversity hotspot in Southwest WA, our beaches and the
rest. ‘Wet’ would presumably be more beneficial than ‘dry’, at least where salinity and drought are the
dominating threats. We have been unable to consider this in detail.
However, it is uncertain how much the Great Barrier Reef stands to gain in the mitigation scenarios,
as the mechanisms that will damage it in future (reaching the temperature tolerance threshold and
having started a large-scale process of ocean acidification) are going to take considerable time to
reverse with long-lasting greenhouse gases already present in the atmosphere and no chance of
introducing mitigating policies overnight.
Similar considerations apply to other threats: warming mountain climates, increasing salinity levels,
effects of sea level change and storm surges on beaches and low-lying cities, etc. The reversal
process will take a long time. Much damage will have been done even if work is started tomorrow
towards the ultimate target of only one degree climate change, or less, in accordance with the
mitigation scenarios proposed in the project specification. We have to consider the path towards that
desirable state, not merely the ultimate target itself.
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12
Potential responses and adaptation strategies of Great Barrier Reef
tourism to climate change
Understanding how the Great Barrier Reef and its tourist industry might change or adapt is critical for
government planning and policy development. While not all-inclusive, we feel that the following
adaptive responses are likely to occur within the Great Barrier Reef tourist industries:
•
To the extent that world tourism is governed by multinational companies, they will look at the
world as its ‘oyster’. In this respect, multinational companies will plan relatively less for Australia
and relatively more for those regions of the world that are less under threat (refer Figure 6).
•
Within Australia, larger tour operators are likely to shift south as ecological systems change away
from the iconic states that they are in today. This may occur gradually or may be subject to
particular tipping points (e.g. following a series of strong bleaching events in which coral cover
and reef quality deteriorate suddenly). To some extent, space and opportunity may play important
roles to whether the larger operator remains in Australia or is forced offshore.
•
A large part of the tourist industry associated with the Great Barrier Reef consists of small
operators. These operators, with lower mobility and flexibility of the larger operators, are likely to
adapt the way their businesses are portrayed. Current images of pristine reef and rainforest may
be replaced by those drawing more on other activities (e.g. golf courses, horse riding on
beaches). How successful these are likely to be will depend very much on global demand and
how it may change (e.g. rising wealth in China, India and other Asian countries in particular),
which may falter given the relatively remote, and hence high-cost travel, location of current tourist
hubs such as Townsville and Cairns.
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The need for further research
Detailed projections of the changes faced by Great Barrier Reef tourism will be important for any
adaptation plan. Currently, our ability to project how the Great Barrier Reef will change is fairly limited
and would benefit from a better understanding of the links between changes in the global ocean, the
local oceanography and the ecology of the Great Barrier Reef. This will require partnerships between
Australian research teams and collaborations with international satellite providers such as the USbased National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and
Space Administration (NASA).
Our understanding of how coral reef ecosystems will change is currently limited to a few key
organisms such as corals and fish. As described in the recent comprehensive vulnerability
assessment coordinated by the Great Barrier Reef Marine Park Authority (Johnson and Marshall
2007), many other key groups of organisms and ecological processes are poorly described in terms of
their response to climate change. It is recommended that the results of this assessment be
considered in formulating a forward focused research strategy for understanding how the Great
Barrier Reef will respond to climate change. The last area that requires considerable research (as
regards required biological information) is the looming issue of ocean acidification. We currently have
a very poor understanding of how organisms will respond to changes in ocean acidity and carbonate
levels. There is growing evidence that this change will affect more than simply the calcifying
organisms, and may have brought impacts on reproduction, metabolism and growth. It is also clear
that this change to ocean chemistry may interact and produce synergistic effects with changes in sea
temperature and variations driven by climate change. Understanding these changes must be a priority
if we are to fully understand and project the changes that are likely to occur on the Great Barrier Reef.
There are also some significant gaps in our understanding of how the social and economic systems
that are associated with the Great Barrier Reef will respond to climate change. Despite its importance,
the ramifications of climate change for tourism is a relatively under-researched topic. A beginning was
made at the Djerba conference in 2003. We look forward to be publication of final paper from the 2007
Davos conference on future patterns in world tourism which promises to be a major step (Figure 6
was derived from the summary of that paper).
Research needs to be done to better understand Australia’s position in world tourism today and how
this could change over the coming years according to different climate scenarios. Although one of the
background papers to the present study (Hoegh-Guldberg 2008) contains a large number of
references, much of the underlying research into the various types of tourism (reef, snow, other nature
based, beach, and other lesser types such as wine, whales, etc) should be tackled in a consistent
framework, rather than ad hoc as now. We feel that this must be done in an objective way to avoid
biased industry perspectives and distortions.
A similar approach needs to be applied to regional studies of tourism in such as that in Tropical North
Queensland; we still have only a limited, and possibly outdated, knowledge of which visitors are
attracted to the coral reef as such, and who would still come to pursue other activities or simply for a
balmy climate. An in-depth understanding of the relative vulnerabilities and interactions between
regions is important in order to get the full picture of how things will change. In this regard, scenario
planning as a tool has proven a highly useful technique in strategic studies since it was introduced as
a major discipline 30–40 years ago, as classical forecasting techniques became more unreliable as
the world became more complex. It was a major feature of the analysis of the future of the Great
Barrier Reef by our previous study (Hoegh-Guldberg and Hoegh-Guldberg 2003) and is currently
being refined in another study of coral reef futures, in the Florida Keys, by one of the authors (H.
Hoegh-Guldberg, for NOAA in the USA).
Fully extended, scenario planning casts the net wide to cover a range of plausible futures, from ‘worst’
to ‘better’ cases, as a base for remedial long term planning. Such an approach—taking all sociocultural, technological, ecological, economic and political factors into account—starts in the form of
alternative ‘stories’ about three or four possible future worlds, covering a wide range of plausible
cases. They should start at global level like the IPCC scenarios, but must also take account of local
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factors generated both from scientific and economic data and equally importantly from local insights
derived from local community scenario-planning workshops. Without such local contents and insights
the approach is less likely to succeed, and be accepted. While based on narratives, the end result can
(and should) be adapted to include projected key economic, social and environmental statistics
expected in each scenario. The Great Barrier Reef scenarios included such quantitative content.
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Conclusions
In reviewing the impact is of climate change on the Great Barrier Reef, several things become clear.
Firstly, coral reef ecosystems such as the Great Barrier Reef are highly vulnerable to the impacts of
global warming and ocean acidification. Coral reef ecosystems will change fundamentally from the
condition that they are in today if atmospheric CO2 exceeds 450 ppm. This will almost certainly affect
their value to the tourist industry. Secondly, the projected shifts in tourist activity will depend ultimately
on the extent of change as well as national and international competitive relationships within the
tourist industry. The most vulnerable part of the tourist industry will be the smaller operators which do
not have the capacity and flexibility for changing their business in response to climate change driven
variation in business opportunity. Thirdly, while we have a broad understanding of the changes that
are likely to occur over the next few decades and the century, there is an urgent need to understand
the interaction between the Great Barrier Reef and global changes in ocean circulation and
temperature, as well as the full suite of organisms that are likely to be affected. Despite some
remedial efforts since about 2003, it is also clear that a fundamental gap remains in our understanding
of the dependency of the tourist industry on climate change, and the interconnectivity between
national and international competitors. These gaps must be addressed as a matter of priority if we are
to gain the insight and understanding that is necessary for the adaptation planning that will be
required if Australia is to succeed in the coming period of global environmental stress.
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Acknowledgments
The authors are grateful to the Hoegh-Guldberg/Dove research laboratory at the University of
Queensland, Sophie Dove and Isobel Hoegh-Guldberg for incisive discussion surrounding impacts of
climate change on corals reefs. OHG acknowledges the support of the Coral Reef Targeted Research
Project (www.gefcoral.org) and the ARC Centre for Excellence for Coral Reef Studies
(www.coralcoe.org.au).
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28. WTO et al. (2007) United Nations World Tourism Organization, United Nations Environment Program and
World Meteorological Organization, Climate Change and Tourism: Responding to Global Challenges—
Summary. http://www.unwto.org/climate/support/en/pdf/summary_davos_e.pdf.
29. Wachenfeld, D.R. 1997, ‘Long-term trends in the status of coral reef-flat benthos—The use of historical
photographs’, pp. 134–148 in State of the Great Barrier Reef World Heritage Area Workshop: Proceedings of
a Technical Workshop held in Townsville, Queensland, Australia 27–29 November 1995, eds., D.R.
Wachenfeld, J. Oliver & K. Davis, Workshop No. 23, Great Barrier Reef Marine Park Authority, Townsville.
30 Wilkinson, C. (ed.), (2004), Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine
Science, Townsville, Queensland, Australia. 301 p.
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Appendix 1 Vulnerable tourist regions, Australia
The table overleaf was derived from domestic and international visitor statistics compiled by the
official state and territory tourism agencies. The estimates are of the number of holiday tourist bed
nights for the year 2002.
The regions shown are as in the relevant publications used in the analysis (listed under sources on
the last page). Some states have subsequently changed their regional definitions.
The column showing ‘most important influences’ summarises a detailed assessment assigning scores
between 5 (most threatened) and 0 (not significantly threatened) to the ten different tourism types
shown in Table 1 (Section 4). It also assigns score to five deterrents, from 5 (greatest threat) to 0 (no
significant threat). These are also shown in Table 1.
The resulting analysis, for two different CSIRO climate change scenarios to 2070 as they existed in
2003 (‘wet’ DARLAM and ‘dry’ Mark 3), is not reproduced, but gives rise to the two final columns of
Appendix 1: total score and occurrence of extreme observations (scores of 4 and 5) in one or both of
the scenarios.
The regions are ranked state by state according to the total score obtained in the analysis. The most
threatened regions are colour-coded dark orange (scores of 25 and above), the next group (20–24)
blue, and the third group (15–19) buff. The same colour code is used to identify the extreme
observations themselves, on the last page.
The various vulnerability components are described in detail in Hoegh-Guldberg (2008, available at
http://economicstrategies.files.wordpress.com/2008/02/background-tourism-paper-updated.pdf).
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Region
Northern Rivers
North Coast NSW
Sydney
Snowy Mountains
The Murray
ACT/Canberra
Central Coast
South Coast
Hunter
Riverina
Blue Mountains
Illawarra
Outback NSW
New England North West
Explorer Country
Capital Country excluding ACT
Most important influences
Rainforests, beaches, fishing, whales, bushfires, UV
Wetlands, beaches, fishing, whales, native flora, bushfires
Beaches, bushfires, urban heat
Snow, native flora, wetlands
Salinity, fishing, vineyards
Bushfires, urban heat, UV
Beaches, bushfires
Beaches, fishing, whales, bushfires
Vineyards, wetlands, bushfires
Salinity, vineyards
National parks, bushfires
Beaches, fishing, bushfires
UV, national parks, wetlands
National parks, wetlands
Wetlands, vineyards
Vineyards, national parks, UV
Domestic International Total International "V" score Extremes
4,780
6,445
9,121
1,929
1,486
1,615
2,126
8,246
3,575
887
1,080
1,124
564
1,463
1,623
1,100
920
347
13,484
38
81
462
75
242
236
56
163
68
28
176
98
9
5,700
6,792
22,604
1,967
1,566
2,077
2,201
8,489
3,811
942
1,243
1,192
592
1,640
1,721
1,109
16%
5%
60%
2%
5%
22%
3%
3%
6%
6%
13%
6%
5%
11%
6%
1%
23
21
18
15
14
14
12
12
11
11
10
8
8
7
7
5
Total NSW/ACT
47,164
16,482
63,646
26%
12
1
Legends, vineyards, High Country Snow, native flora, vineyards, fishing, bushfires, UV
Murray Outback
Salinity, fishing, national parks, wetlands
Great Ocean Road
Beaches, fishing, native flora, whales, bushfires
Phillip Island/Gippsland
National parks, beaches, fishing, bushfires
The Murray
Salinity, national parks, fishing, wetlands, UV
Bays & Peninsulas
Bushfires, beaches, fishing, whales, wetlands
Lakes & Wilderness
Fishing, national parks, wetlands, bushfires
Goulburn Murray Waters
Vineyards, salinity
Yarra Valley/Dandenongs Vineyards, national parks, bushfires
Grampians
Vineyards, national parks, bushfires
Melbourne
Urban heat, bushfires
Macedon Ranges
National parks, bushfires
Goldfields
National parks, bushfires
2,434
1,440
5,364
3,605
3,607
3,643
875
1,529
567
791
6,059
393
3,420
48
22
508
150
78
138
49
23
19
89
4,503
3
223
2,482
1,461
5,871
3,755
3,685
3,781
925
1,552
585
881
10,562
396
3,643
2%
1%
9%
4%
2%
4%
5%
1%
3%
10%
43%
1%
6%
23
17
17
17
16
14
12
10
9
8
7
5
5
1
2
Total Victoria
33,726
5,853
39,579
15%
12
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1
2
1
2
1
1
2
2
1
1
2
1
1
29
Region
Tropical North Queensland
Townsvil e
Whitsundays
Fraser Coast
Brisbane
Capricorn
Gladstone
Gold Coast
Outback Queensland
Mackay
Sunshine Coast
Bundaberg
Toowoomba/Golden West
Most important influences
Coral, rainforests, fishing, UV, mangroves, beaches, disease
Fishing, national parks, UV, coral, mangroves, wetlands
Fishing, coral, wetlands, UV
UV, fishing, rainforest, wetlands, whales
Urban heat, UV, wetlands, bushfires
UV, beaches, fishing, coral
UV, beaches, fishing, coral
Beaches, UV, national parks
UV, rainforests, wetlands, disease
UV, beaches, fishing
Beaches, UV
UV, fishing
UV, national parks
3,609
1,129
1,675
2,744
4,387
948
900
12,308
658
685
7,485
1,127
1,180
8,082
1,445
2,675
3,469
6,317
1,127
1,016
15,434
738
738
8,461
1,256
1,200
55%
22%
37%
21%
31%
16%
11%
20%
11%
7%
12%
10%
2%
33
26
22
18
16
12
11
11
11
11
10
7
5
2
2
2
1
2
1
1
2
2
1
2
1
1
25%
15
1
Salinity, wetlands, fishing, vineyards
National parks, vineyards, wetlands, salinity
Salinity, vineyards, fishing, wetlands
Vineyards, bushfires
National parks, native flora, wetlands
Beaches, fishing
Urban heat, UV
Vineyards
National parks, beaches, fishing
National parks, native flora
National parks, beaches, fishing
Vineyards
Wetlands, national parks
38,835 13,123 51,958
14%
4% 12%
280
22
301
920
47
967
189
61
250
147
7
154
103
98
201
92
71
163
3,410 2,144 5,555
131
39
170
552
58
610
268
85
352
440
9
449
92
5
96
474
128
601
7%
5%
24%
5%
49%
44%
39%
23%
10%
24%
2%
5%
21%
20
17
14
9
9
9
8
8
8
8
8
5
4
2
7,098
28%
9
Total Queensland
Murraylands
Fleurieu Peninsula
Riverland
Adelaide Hil s
Outback SA
Kangaroo Island
Adelaide
Barossa
Eyre Peninsula
Flinders Ranges
Yorke Peninsula
Clare Valley
Limestone Coast
Total South Australia
Domestic International Total International "V" score Extremes
4,473
316
1,000
725
1,930
179
116
3,126
80
53
976
129
20
2,774
9,872
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0
30
Region
Most important influences
Domestic International Total International "V" score Extremes
South West
Salinity, native flora, vineyards, fishing, wetlands, whales
Gascoyne
Coral, native flora, salinity, fishing, whales, bushfires
Perth
Urban heat, native flora, vineyards, wetlands, beaches, UV
Peel
National parks, native flora, fishing, wetlands
Kimberley
UV, national parks, wetlands, disease
Great Southern
Salinity, native flora, fishing
South East
Native flora, salinity, fishing
Pilbara
Native flora, whales, fishing, UV, disease
Mid West
Native flora, fishing
Goldfields (including south coast) Native flora, UV, whales
Heartlands
Native flora, UV, national parks
3,211
826
2,846
675
1,399
867
368
353
1,582
415
998
266
113
2,602
34
67
123
29
70
123
34
78
3,477
940
5,448
709
1,466
989
396
423
1,704
449
1,075
8%
12%
48%
5%
5%
12%
7%
17%
7%
7%
7%
28
25
23
21
21
20
18
16
13
9
7
Total Western Australia
13,539
3,538
17,077
21%
18
1
335
106
283
370
866
228
232
5
3
5
5
46
23
5
340
109
288
375
912
251
237
1%
3%
2%
1%
5%
9%
2%
12
11
10
10
9
8
4
1
2,420
92
2,512
4%
9
0
1,983
1,712
509
186
606
867
147
32
2,589
2,579
656
218
23%
34%
22%
15%
27
14
11
7
2
2
2
2
4,390
1,652
6,042
27%
15
2
43,513 190,685
23%
13
1
West Coast
Northern
East Coast
North West
Greater Hobart
Southern
Greater Launceston
National parks, fishing, rainforest, bushfires
Snow, national parks, fishing, wetlands
National parks, fishing, wetlands, native flora
National parks, wetlands, rainforest, bushfires
Fishing, national parks, bushfires
National parks, fishing
Fishing, national parks
Total Tasmania
Top End
Centre
Katherine
Tennant Creek
Total Northern Territory
Total Australia
National parks, UV, urban heat, wetlands
UV, national parks, native flora, bushfires, disease
UV, national parks, disease
UV, disease
147,172
2
2
1
2
2
1
2
Sources and notes, see next page
Garnaut Climate Change Review
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Sources: Tourism New South Wales, Regional Profile Year Ended December 2001. Tourism Victoria, Visitors to Victoria’s Regions, 1998 to year ended March 2003. Tourism Queensland, Queensland
Update and Regional Update – Summary results for the year ended December 2002. South Australian Tourism Commission, Tourism Profile, and Tourism Research: Overnight Travel – South Australian
Regions Year Ended March 2003. Western Australian Tourism Commission, Research Review on Domestic Visitor Activity 2002. Tourism Tasmania, Tasmanian Visitor Survey 1997/98 to 2001/02.
Northern Territory Tourism Commission, The Economic Value of Tourism (2001/02). Australian totals checked against (then) BTR statistics and found within 3%. The statistics are estimated holiday
visitor nights.
"V" score: "V" for vulnerability to climate change. Based on an assessment of each of the factors contributing go vulnerability on a scale from 1 (mild) to 5 (severe), for two
alternative climate change scenarios devised by CSIRO (DARLAM ("wet") and Mark 3 ("dry")).
Extremes: Scores of 4 and 5 on the vulnerability scale. "1" if rated for one of the two alternative scenarios, "2" if rated for both, the factors being:
Northern Rivers
North Coast NSW
Hunter
Central Coast
Blue Mountains
Sydney
ACT/Canberra
Snowy Mountains
Outback NSW
Riverina
The Murray NSW
National parks, beaches, fishing, bushfires, UV
Wetlands
Vineyards
Bushfires
Bushfires
Beaches, bushfires
Bushfires
Snow, national parks, native flora
UV
Salinity, vineyards
Salinity, vineyards
Murray Outback
Salinity, fishing, national parks
Goulburn Murray Waters
Salinity, vineyards
Legends, vineyards, High Country Snow, national parks, native flora
Phillip Island/Gippsland
Bushfires
The Murray Vic
Salinity, fishing
Tropical North Queensland
Townsville
Whitsundays
Mackay
Capricorn
Gladstone
Bundaberg
Fraser Coast
Reefs, rainforests, beaches, fishing, bushfires, UV
National parks/rainforests, fishing, UV
Reefs, fishing, UV
UV
UV
UV, reefs
UV
UV, national parks
Sunshine Coast
Brisbane
Gold Coast
Toowoomba/Golden West
Outback Queensland
Beaches, UV
Urban heat, UV
Beaches, UV
UV
UV
Adelaide Hills
Barossa
Murraylands
Riverland
Bushfires
Vineyards
Salinity
Salinity, vineyards
South East WA
Gascoyne
Kimberley
Perth
Peel
Great Southern
South West
Salinity
Reefs
National parks, wetlands, UV
Urban heat, UV
National parks, native flora, wetlands
National parks, native flora, salinity
National parks, native flora, salinity, vineyards
West Coast Tas
National parks
Top End
Katherine
Tennant Creek
Centre
National parks, wetlands, UV, urban heat, disease
UV, disease
UV
UV
Garnaut Climate Change Review
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Appendix 2 Physical climate scenarios
To understand the impacts of change under a range of possible climate futures (with and without
mitigation), a set of physical climate change scenarios have been developed for the Garnaut Review
to use in the economic modelling exercise. These scenarios were determined by CSIRO climate
scientists in consultation with the Garnaut Review Secretariat.
The project teams should have regard for these scenarios when defining the impacts of climate
change on their sector of interest.
R1—Hot, dry reference scenario—A1FI emissions path, 3°C climate sensitivity, 10th percentile rainfall and
relative humidity surface for Australia (dry extreme), 90th percentile temperature surface. Mean global warming
reaches 4.5°C in 2100.
R2—Warm, wet reference scenario—A1FI emissions path, 3°C climate sensitivity, 90th percentile rainfall and
relative humidity surface for Australia (wet extreme), 50th percentile temperature surface. Mean global warming
reaches 4.5°C in 2100.
A—Dry reference scenario—550 ppm CO2 equivalent (CO2 stabilised at 500 ppm), 3°C climate sensitivity, 10th
percentile rainfall and relative humidity surface for Australia (dry extreme), 90th percentile temperature surface.
Mean global warming reaches 1.0°C in 2100.
B—Wet reference scenario—550 ppm CO2 equivalent (CO2 stabilised at 500 ppm), 3°C climate sensitivity, 90th
percentile rainfall and relative humidity surface for Australia (wet extreme), 50th percentile temperature surface.
Mean global warming reaches 1.0°C in 2100.
C—Median reference scenario—450 ppm CO2 equivalent (CO2 stabilised at 420 ppm), 3°C climate sensitivity,
50th percentile rainfall and relative humidity surface for Australia, 50th percentile temperature surface. Mean
global warming reaches 0.55°C in 2100.
where R1 and R2 are the reference cases, based on the IPCC Special Report Emissions Scenario (SRES) A1FI;
and A, B, C are the comparative mitigation scenarios based on an emission stabilisation target of between
450ppm and 550ppm CO2-equivalent.
The SRES A1FI scenario stems from the IPCC family of A1 storylines. 1 The A1 storyline and scenario
family describes a future world of very rapid economic growth, global population that peaks in midcentury and declines thereafter, and the rapid introduction of new and more efficient technologies.
Major underlying themes are convergence among regions, capacity building, and increased cultural
and social interactions, with a substantial reduction in regional differences in per capita income. The
A1 scenario family develops into three groups that describe alternative directions of technological
change in the energy system. The three A1 groups are distinguished by their technological emphasis:
fossil intensive (A1FI), non-fossil energy sources (A1T), or a balance across all sources (A1B).
In considering the range of IPCC scenarios, their storylines and assumptions, Professor Garnaut
made the judgment that A1Fi presented a business as usual future he thought most likely, in the
absence of a global government mitigation response. A1Fi therefore forms the reference case for the
Garnaut Review economic modelling.
1
Nakicenovic, N. (2000), Emissions Scenarios: A Special Report of Working Group III of the Intergovernmental Panel on
Climate Change, Cambridge University Press UK.
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