Climate Change Background Study - Climate Change and Peak Oil Strategy - Sunshine Coast Climate Change Background Study - Sunshine Coast Council
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Sunshine Coast Climate Change Background Study
Climate Change
Background Study
Climate Change and
Peak Oil Strategy
2010-2020
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 1Sunshine Coast Climate Change Background Study
Contents
1.0 Introduction ............................................................................................................................. 5
1.1 The Climate Change and Peak Oil Strategy ........................................................................ 5
1.2 The Policy Context .............................................................................................................. 5
1.3 Review of the Climate Change and Peak Oil Strategy and this background study............... 5
2.0 A scientific overview of climate change ................................................................................... 7
2.1 Introduction ......................................................................................................................... 7
3.0 The need to manage climate change .................................................................................... 11
3.1 Predicting the future climate.............................................................................................. 11
3.1 (a) Emissions scenarios ...................................................................................................................11
3.1 (b) Global Circulation Models (GCMs) .............................................................................................12
3.2 Actual global greenhouse gas emissions .......................................................................... 13
3.3 Australian emissions ......................................................................................................... 14
3.4 Regional analysis for the Sunshine Coast ......................................................................... 15
4.0 Projected climate variability for the Sunshine Coast .............................................................. 16
4.1 Temperatures.................................................................................................................... 16
4.1 (a) Current annual mean temperatures............................................................................................17
4.1 (b) Future annual mean temperatures .............................................................................................18
4.1 (c) Current average minimum winter temperatures .........................................................................19
4.1 (d) Current average maximum summer temperatures.....................................................................19
4.1 (e) Projected shifts in winter and summer temperatures .................................................................19
4.1 (f) Extreme temperatures ................................................................................................................20
4.1 (g) Implications of shifts in minimum temperatures..........................................................................20
4.1 (h) Implications of shifts in maximum temperatures ........................................................................21
4.2 Rainfall.............................................................................................................................. 21
4.2 (a) Historic changes in annual mean rainfall for the Sunshine Coast..............................................21
4.2 (b) Changes in annual mean rainfall for the Sunshine Coast ..........................................................22
4.2 (c) Changes in mean seasonal rainfall ............................................................................................23
4.2 (d) Changes in mean monthly rainfall ..............................................................................................23
4.2 (e) Rainfall intensity and flooding .....................................................................................................25
4.3 Sea level rise .................................................................................................................... 26
4.3 (a) Measured global sea level rise ...................................................................................................26
4.3 (b) Projected mean sea level rise ....................................................................................................27
4.3 (c) Expectations for sea level rise....................................................................................................29
4.3 (d) Planning for future sea level rise for the Sunshine Coast ..........................................................29
4.3 (e) Sea level extremes .....................................................................................................................30
4.4 Wind.................................................................................................................................. 31
4.4 (a) Extreme winds ............................................................................................................................31
4.5 Extreme events ................................................................................................................. 31
4.5 (a) Tropical Cyclones .......................................................................................................................31
4.5 (b) Storm tides and wave set up ......................................................................................................32
4.5 (c) Hail storms..................................................................................................................................32
4.5 (d) Droughts and bushfires...............................................................................................................33
4.6 Acidification of the oceans................................................................................................. 33
4.7 Uncertainty........................................................................................................................ 34
4.7 (a) The Current Climate ...................................................................................................................34
4.7 (b) The Future Climate .....................................................................................................................34
4.7 (c) Earth’s sensitivity to the changes ...............................................................................................35
5.0 Approaches to managing climate change.............................................................................. 36
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 2Sunshine Coast Climate Change Background Study
5.1 A Risk Management Approach.......................................................................................... 36
5.2 Climate change management............................................................................................ 37
5.3 Mitigation........................................................................................................................... 38
5.4 Adaptation......................................................................................................................... 39
5.5 Timeframes for decision making........................................................................................ 40
5.6 Addressing perceptions of climate change ........................................................................ 41
6.0 Climate change implications for Council and the community................................................. 42
6.1 Implications for natural systems ........................................................................................ 42
6.1 (a) Water resources .........................................................................................................................42
6.1 (b) Biodiversity .................................................................................................................................43
6.1 (c) Waterways and wetlands............................................................................................................47
6.1 (d) Air quality ....................................................................................................................................47
6.2 Implications for Infrastructure and Assets.......................................................................... 48
6.2 (a) Stormwater systems ...................................................................................................................48
6.2 (b) Water supply systems.................................................................................................................49
6.2 (c) Wastewater collection and treatment systems ...........................................................................49
6.2 (d) Transport systems ......................................................................................................................50
6.2 (e) Telecommunications, power and gas systems...........................................................................51
6.2 (f) Waste management facilities......................................................................................................51
6.2 (g) Development in the coastal margins ..........................................................................................52
6.3 Implications for People and Society................................................................................... 53
6.3 (a) A growing population ..................................................................................................................53
6.3 (b) Vulnerable age groups in the community ...................................................................................53
6.3 (c) Health implications......................................................................................................................55
6.3 (d) Factors affecting resilience and adaptive capacity.....................................................................56
6.4 Implications for the economy and its development ............................................................ 57
6.4 (a) Market and competitiveness risk ................................................................................................57
6.4 (b) Impacts on systems and industries ............................................................................................57
6.4 (c) Food production..........................................................................................................................58
6.4 (d) Tourism and service industries ...................................................................................................58
6.4 (e) Greenhouse gas emissions ........................................................................................................58
6.4 (f) Disaster management and emergency service facilities ............................................................59
6.5 Organisational implications ............................................................................................... 60
6.5 (a) Planning and policy.....................................................................................................................60
6.5 (b) Insurance ....................................................................................................................................60
6.5 (c) Special considerations for sea level rise, storm surge and coastal erosion...............................61
6.5 (d) Risks from multiple impacts ........................................................................................................62
7.0 Climate change initiatives ..................................................................................................... 63
7.1 Key international responses and programs ....................................................................... 65
7.1 (a) Intergovernmental Panel for Climate Change (IPCC) ................................................................65
7.1 (b) United Nations Framework Convention on Climate Change (UNFCCC) ...................................65
7.1 (c) The Kyoto Protocol .....................................................................................................................65
7.1 (d) ICLEI - Local Governments for Sustainability.............................................................................66
7.2 Federal approaches .......................................................................................................... 66
7.2 (a) Commonwealth Scientific and Industrial Research Organisation (CSIRO)................................66
7.2 (b) National Climate Change Adaptation Framework ......................................................................66
7.2 (c) National Greenhouse and Energy Reporting System (NGERS) ................................................67
7.2 (d) Carbon Pollution Reduction Scheme (CPRS) ............................................................................67
7.2 (e) Renewable Energy Target Scheme............................................................................................67
7.2 (f) Climate Adaptation National Research Flagship........................................................................68
7.2 (g) National Climate Change Adaptation Research Facility.............................................................68
7.2 (h) Local Adaptation Pathways (LAP) grants ...................................................................................68
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7.3 State responses ................................................................................................................ 69
7.3 (a) ClimateQ: toward a greener Queensland ...................................................................................69
7.3 (b) Toward Q2: Tomorrow’s Queensland.........................................................................................69
7.3 (c) Draft Queensland Coastal Plan 2009 .........................................................................................69
7.4 Regional policy responses and initiatives .......................................................................... 70
7.4 (a) South East Queensland (SEQ) Regional Plan 2009–2031 ........................................................70
7.4 (b) Southeast Queensland Climate Adaptation Research Initiative (SEQCARI) .............................70
7.4 (c) Sustainability Research Centre - University of the Sunshine Coast ..........................................70
7.5 Sunshine Coast Council initiatives .................................................................................... 71
7.5 (a) Corporate Carbon Accounting and Management Project...........................................................72
8.0 Glossary................................................................................................................................ 74
9.0 Acronyms.............................................................................................................................. 78
10.0 References ........................................................................................................................... 79
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 4Sunshine Coast Climate Change Background Study
1.0 Introduction
The Climate Change Background Study is a supporting document for the Sunshine Coast Climate
Change and Peak Oil Strategy 2010 – 2020 (the Climate Change and Peak Oil Strategy).
1.1 The Climate Change and Peak Oil Strategy
It is the goal of the Climate Change and Peak Oil Strategy ‘
.
The Climate Change Background Study identifies the basis for the policy approaches in the Climate
Change and Peak Oil Strategy relevant to climate change and its related themes: mitigation,
adaptation and leadership.
1.2 The Policy Context
Council’s Corporate Plan 2009-2014 promotes policy actions which are intended to ensure the
region’s environmental, social and economic prosperity.
The Corporate Plan objective is to be achieved through the implementation of environmental, social
and economic strategies including the Climate Change and Peak Oil Strategy (Figure 1.1).
The Climate Change and Peak Oil Strategy is not a stand alone document. Consistent with the
approach of mainstreaming which is identified in this document (pp 37), climate change
considerations need to be integrated across other policies, plans and strategies developed by
Council.
1.3 Review of the Climate Change and Peak Oil Strategy and this
background study
A formal review of the Climate Change and Peak Oil Strategy is to be undertaken every five
years to reflect developments in science, technology and government policy direction. As a
precursor, the Climate Change Background Study will be reviewed in order to ensure that the
Strategy is appropriately informed.
Interim changes to the Climate Change Background Study may also be necessary to
accommodate new scientific understanding, further IPCC reports or recommendations and
findings from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) or
Australian Government Department of Climate Change.
Where practical, these developments should be incorporated into the Climate Change
Background Study as part of the triennial review process which is identified in Section 4.4.2 of
the Climate Change and Peak Oil Strategy.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 5Sunshine Coast Climate Change Background Study
Figure 1.1: The hierarchy of policy approaches, including the Climate Change and Peak Oil Strategy, which
support the Sunshine Coast Council’s Corporate Plan.
In addition to supporting the Climate Change and Peak Oil Strategy, the Climate Change Background
Study can be used to:
Ź Inform Council planning and operational activities and the Planning Scheme;
Ź Guide Council and community decision-making
Ź Engage community and educate stakeholders
Ź Drive a range of actions to deliver upon the goal
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 6Sunshine Coast Climate Change Background Study
2.0 A scientific overview of climate change
2.1 Introduction
Through much of human history the earth has had a relatively steady, warm temperature which is
attributed to gases such as water vapour, carbon dioxide (CO2) and methane in the atmosphere.
Without these, the earth would be much colder than it is and most of the water on the planet would be
frozen. At certain levels, these ‘greenhouse gases’ make the planet liveable for humans and many
other kinds of plants and animals by trapping some of the heat radiating outward from the earth
(Figure 2.1), much like the walls of a greenhouse trapping heated air. This process of limiting heat
loss through the atmosphere is called the ‘greenhouse effect’.
Figure 2.1: The Greenhouse Effect (Source: Snover et. al. 2007)
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 7Sunshine Coast Climate Change Background Study
Humans have released large amounts of heat-trapping greenhouse gases into the atmosphere over a
short period of time (Table 2.1) through activities such as:
Ź Burning fossil fuels (e.g. oil, coal, natural gas)
Ź Agricultural practices
Ź Clearing forests
Ź Land settlement.
Since about 1750 this rapid and large release of greenhouse gases has caused important changes in
the composition of the earth’s atmosphere and, consequently, in the global climate.
The enhanced greenhouse effect is becoming more evident through an associated shift in the
‘radiative forcing’ factors which regulate global, regional and local weather patterns.
‘Radiative forcing’ factors influence the amount of solar energy which is retained in the atmosphere
and impact on the cooling of the planet (e.g. ice sheets, clouds, water vapour) and heating of the
planet (carbon dioxide and methane).
While these ‘radiative forcing’ factors have been responsible for a variable but relatively stable global
climate, emissions of carbon dioxide, methane and other greenhouse gas are shifting this balance
towards a more volatile and variable climate. Over time, there will be a continuing shift in the balance
of the ‘radiative forcing’ factors with associated shifts in our weather patterns as the atmospheric
concentrations of greenhouse gas emissions increase.
Table 2.1: Changes in greenhouse gas concentrations between 1750 (the start of the Industrial Age) and
2005. Concentrations of carbon dioxide are measured in parts per million (ppm), which refers to the total
number of carbon dioxide molecules per one million molecules of dry air by volume. Methane and nitrous oxide
are measured in parts per billion (ppb). (Source: Snover et. al. 2007)
While changes in the atmospheric concentration of greenhouse gases in Figure 2.2 are important, the
key concern for the climate change is the associated disturbance of the carbon cycle.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 8Sunshine Coast Climate Change Background Study
Figure 2.2 Changes in the atmospheric concentration of three important greenhouse gases (Source: Snover
et. al. 2007)
Carbon dioxide concentration levels in the atmosphere now exceed any previous CO2 levels that
have ever been measured or estimated and therefore there is an element of additional uncertainty
with regard to the potential future shifts in the climate that continuing greenhouse gas emissions may
have (Figure 2.3).
There is growing concern that significant adverse shifts in the global climate, well beyond those we
that have been measured or experienced, could result from the growing greenhouse gas
concentrations in the atmosphere.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 9Sunshine Coast Climate Change Background Study
Figure 2.3 Human disturbance of the carbon cycle: an earth system perspective
(Source: Steffen 2009)
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3.0 The need to manage climate change
Mounting physical evidence indicates that climate change is in motion as a result of the greenhouse
gases already accumulated in the atmosphere. Many of the changes projected until the middle of the
21st century will be driven by existing greenhouse gas concentrations (Hansen et. al. 2005, Meehl et.
al. 2005, Wigley 2005, IPCC 2007).
Even if greenhouse gas emissions are stabilised, some degree of warming would still occur globally
due to the increased concentration of greenhouse gases in the atmosphere and the lag time of the
earth’s oceans and atmosphere to warm (Hansen et. al. 2005, Meehl et. al. 2005, Wigley 2005, IPCC
2007). However, reducing greenhouse gas emissions will limit the severity of long-term future
impacts (Hansen et. al. 2005, Meehl et. al. 2005, Wigley 2005, IPCC 2007).
3.1 Predicting the future climate
Climate change projections are an estimate of the response of the climate system to possible
greenhouse gas and aerosol emissions over the next century. Such projections are typically based
on climate model simulations.
The modelling methodology for generating climate change projections is shown in Figure 3.1.
Figure 3.1 The modelling methodology for generating climate change projections (Source: Climate Change
Catchments and Coasts, University of the Sunshine Coast)
Emission Scenarios
Carbon Cycle Model
Atmospheric
Concentrations
Radiative Models
Radiative Forcing
Global Circulation
Models
Global Warming
3.1 (a) Emissions scenarios
The impacts of climate change will be significantly influenced by the greenhouse gas emissions
which occur now and in the future.
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Emissions scenarios have been devised to provide a standardised method for estimating the
potential future concentrations of greenhouse gas emissions. These scenarios are based on
assumptions about the future evolution of society, including assumptions about demographic, socio-
economic, and technological developments.
Figure 3.2 provides an indication of commonly used assumptions which have been utilised in the
Intergovernmental Panel for Climate Change (IPCC) Emissions Scenarios.
Figure 3.2: Assumptions utilised in the commonly used IPCC Emissions Scenarios (Source: Climate Change
Catchments and Coasts, University of the Sunshine Coast)
Fossil Fuel Technologies
Consumer Economies Notes
Personal Wealth A1FI •These scenarios do not
(Fossil Fuel Intensive)
Economic A consider mitigation
A1
A1T
(Technology Development) A2 programs such as Kyoto.
•A1FI assumes unlimited
A1B fossil fuels. Does not
Societies (Balanced Development) consider peak oil
Values •A1T considered by some
as unlikely in next 50
years. (A2 may be the
B1 B2 realistic worst case).
Environmental B •B2 generally considered
best case scenario.
Efficient Technologies
Information Economies
Sustainability 1 2
Political
Global Regional
Cohesion
Homogenous Economies Heterogeneous Economies
International Agreements Fragmented & Ethnocentric Policies
Low Population Growth Increasing 3rd World Population
Converging per Capita Incomes Diverging per Capita Incomes
To date the published IPCC projections for climate change represent a conservative range of outputs
which have been generated from IPCC SRES Scenarios where the term SRES is a reference to the
IPCC Special Report on Emission Scenarios (SRES) which discusses the scenarios and the outputs
from their use (IPCC 2000).
The estimated changes in greenhouse gas concentrations that are developed for each emissions
scenario are used to evaluate the likely shifts in the build up of energy within the earth’s atmosphere,
the changes this may cause to circulation patterns and the subsequent implications for climate
change.
3.1 (b) Global Circulation Models (GCMs)
Global Circulation Models (GCMs) are complex, three-dimensional climate models that consider a
range of factors with potential to influence our global climate system. They are also referred to as
Global Climate Models.
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GCM outputs have been widely used to assess climate change impacts for various geographical
regions of the world. The IPCC obtains outputs from a range of GCMs which have been developed
by more than a dozen scientific institutions across the globe, including the Australian Commonwealth
Scientific Industrial and Research Organisation (CSIRO), NASA and the Hadley Centre in the United
Kingdom.
GCMs provide outputs at a global scale. Two methodologies exist for translating this information to
regional and sub-regional scales. These processes are referred to as pattern downscaling and
dynamic downscaling.
The projections which are developed by the CSIRO for Australia, and regions within Australia,
generally reflect outputs from dynamic downscaling. The outputs from the SimCLIM model reflect the
pattern downscaling methodology, where outputs are generated by adjusting local climate variables
in accordance with the patterns associated with a selected GCM and climate change scenario.
Projections specific to the Sunshine Coast have mostly been generated using the SimCLIM model.
While SimCLIM itself is not a GCM, it does utilise the outputs generated by various GCMs for the full
range of IPCC SRES scenarios which are reported in the IPCC reports (IPCC 2007, IPCC 2001).
3.2 Actual global greenhouse gas emissions
Actual global greenhouse emissions are now equal to or exceed the highest trajectories for global
greenhouse gas emissions that are associated with the commonly used IPCC Emissions Scenarios
(Figure 3.3).
Figure 3.3 Comparison of actual global greenhouse emissions with the emissions projected using the
commonly used IPCC Emissions Scenarios (Source: Steffen 2009)
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 13Sunshine Coast Climate Change Background Study
Given that increasing greenhouse gas concentrations correlate to projections of more intense climate
change impacts, Figure 2.6 suggests that:
Ź The A1FI scenario may be the most realistic scenario for global climate change
Ź Actual climate variability could be larger and occur over shorter time frames than the projected
changes associated with the A1FI scenario.
Clearly, greenhouse gas emissions need to be addressed to minimise further climate changes. If
emissions continue to increase, there will be fewer opportunities to effectively adapt to the continually
accelerating pace of climate change.
Significant reduction of greenhouse gas emissions is possible, but it is unlikely that greenhouse gas
emissions will be stabilised or reversed in the near term without clear and strong action.
3.3 Australian emissions
“Australia’s per capita emissions are the highest of any developed country”
Ross Garnaut
The Garnaut Climate Change Review Final Report
(Commonwealth of Australia 2008)
As indicated by Figure 3.4, Australian greenhouse gas emissions must be curbed to mitigate risks
associated with accelerated climate change.
Figure 3.4 Australian greenhouse gas emissions: Comparison of actual greenhouse emissions with the paths
projected for emissions reductions associated with limited (‘with measures’) and significant (‘deep emissions
cuts’) mitigation action (Source: Associate Professor B.Miles)
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 14Sunshine Coast Climate Change Background Study
Greenhouse gas emissions can be reduced or reversed with a global transition to a clean
energy economy. However, to avoid the worst climate change impacts greenhouse gas emissions
need to be cut to the point where atmospheric concentrations stabilise and then decline.
Irrespective of the recognition of climate change science, local government in South East
Queensland (SEQ) is obliged to act to:
Ź Address shifts in Federal, State and regional policies
Ź Address growing community concerns regarding increasing climate variability
Ź Prepare for potential policy shifts associated with insurance
Ź Mitigate risks that impact on public health, safety, litigation and Council costs.
3.4 Regional analysis for the Sunshine Coast
The IPCC Fourth Assessment recommends the use of regionally specific estimates of climate
change. Where possible, projections have been modelled for the Sunshine Coast to provide an
indication of expected changes in climate and associated impacts for the region.
Outputs from the SimCLIM model, which provide a regionally specific assessment for the Sunshine
Coast, have been used to inform Council’s Climate Change and Peak Oil Strategy. Outputs from
dynamic downscaling for the SEQ region and sea level projections from a range of sources have
been used to supplement regional data.
Where practical, the SimCLIM projections are based on the outputs from GCMs used by the IPCC,
IPCC SRES Scenarios (A1T for 2020 and A1FI for 2050, 2075 and 2100) and high climate sensitivity.
The modelling also assumes a ‘business as usual’ approach where there is no significant reduction in
global greenhouse gas emissions.
The Sunshine Coast projections will be reviewed to accommodate improved modelling outputs,
changes to IPCC scenarios and any shifts in greenhouse gas mitigation approaches.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 15Sunshine Coast Climate Change Background Study
4.0 Projected climate variability for the Sunshine Coast
Where possible, the following projections for the future climate of the Sunshine Coast have been
derived from SimCLIM modelling software. Council acknowledges the assistance of the University of
the Sunshine Coast in developing these projections. Significant input was provided by the
University’s Climate Change, Coasts and Catchments unit within the Faculty of Science, Health and
Education.
4.1 Temperatures
Based on analysis of observational data, the IPCC (IPCC 2007) has identified that there is evidence
of increasing temperatures across the globe. A simplified analysis of data from a number of weather
stations on the Sunshine Coast appears to support this IPCC statement as, in general terms, the
local data indicates that annual mean temperatures have been increasing across the Sunshine Coast
when compared to the IPCC baseline period from 1961 to 1990 (Figure 4.1).
Figure 4.1: Scatter plot of annual mean temperatures from three Sunshine Coast weather stations (Tewantin
Post Office, Crohamhurst and Nambour DPI) for the periods 1961 to 1990 (blue dots) and 1991 to 2006 (green
dots) and a line of best fit for each period (brown and orange respectively). While considerable variability
between annual mean temperatures can be observed, trends are apparent. For the period from 1961 to 1990
there was a slight trend of decreases in annual mean temperatures while, for the period between 1991 to 2006
there has been a trend of increasing annual mean temperatures for the Sunshine Coast. It should be noted that
data was not available for the Nambour and Crohamhust weather stations for the period from 1961 to 1964 and
this may have affected the trend for that period. A lack of data also prevented the inclusion of trends for the
period prior to 1961. The period 1961 to 1990 was selected as it is consistent with the baseline period utilised in
IPCC reports (IPCC 2007). El Nino and other factors of climatic variability have not been considered in this
analysis.
21.5
Annual Mean Temperature (°C)
20.5
19.5
18.5
17.5
16.5
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010
Year
1961 to 1990 1991 to 1996
(Source: Bureau of Meteorology data for recorded daily temperatures as obtained from SimCLIM. Annual mean
temperatures were excluded where the mean was based on less than 100 days of data. In order to avoid potential
shifts in the mean, other missing data was replaced by the annual mean temperature for the corresponding year.)
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The IPCC (2007) has also indicated that temperatures will continue to shift in concert with increasing
atmospheric concentrations of greenhouse gas emissions. Fewer cold days and more hot days are
expected, with associated shifts in annual and seasonal means and extremes.
4.1 (a) Current annual mean temperatures
Higher annual mean temperatures are associated with the coastal areas while lower annual mean
temperatures are associated with the hinterland areas. Figure 4.2 identifies the distribution of annual
mean temperatures within the Sunshine Coast for the current climate (1961 - 1990).
Figure 4.2: Distribution of annual mean temperatures for the Sunshine Coast for the current climate (1961 -
1990) - (Source: Recorded data provided by the Bureau of Meteorology and included in the SimCLIM Model)
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 17Sunshine Coast Climate Change Background Study
4.1 (b) Future annual mean temperatures
Projections have been modelled for mean annual temperatures for the Sunshine Coast for the 2020,
2050, 2075 and 2100 timeframes as indicated in Figure 4.3.
Figure 4.3: Projected mean annual temperatures for the SCRC area for (a) 2020, (b) 2050, (c) 2075 and (d)
2100 (SimCLIM Model settings: HadCM3 GCM with high sensitivity and IPCC SRES A1T scenario for 2020 and
IPCC SRES A1FI for 2050, 2075 and 2100)
(a) Projected average annual (b) Projected average annual
temperatures for 2020 temperatures for 2050
(c) Projected average annual (d) Projected average annual
temperatures for 2075 temperatures for 2100
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 18Sunshine Coast Climate Change Background Study
These figures indicate there will be warming across the region, with annual mean temperatures
increasing by:
Ź Up to 1°C by 2020
Ź Up to 2.°C by 2050
Ź Up to 4°C by 2075
Ź Up to 6.5°C by 2100.
4.1 (c) Current average minimum winter temperatures
Average winter minimum temperatures vary across the region, reflecting local terrain and climate
processes. Generally, warmer conditions occur towards the coastline while lower average winter
minimum temperatures are recorded further inland. The average minimum winter temperature for the
Sunshine Coast for the period 1961 to 1990 was 7.6°C.
4.1 (d) Current average maximum summer temperatures
The average maximum summer temperature for the Sunshine Coast for the period 1961 to 1990 was
28.2°C. Cooler temperatures occur in areas with hi gher elevations (e.g. Blackall Range).
4.1 (e) Projected shifts in winter and summer temperatures
Consistent with the projected shift in average temperatures for the Sunshine Coast, average
minimum temperatures for winter and average maximum summer temperatures are also projected to
increase over time. This is also consistent with IPCC and CSIRO projections (IPCC 2007, CSIRO
2007a) (Figure 4.4).
Figure 4.4: Current and projected (2020, 2050, 2075 and 2100) average minimum winter temperatures and
average maximum summer temperatures for the Sunshine Coast (Model settings: HadCM GCM with high
sensitivity and IPCC SRES A1T scenario for 2020 and IPCC SRES A1FI for 2050, 2075 and 2100).
40
36.4
34.2
30
31.5
Temperature (°C)
29.4
28.2
20
15.5
10 13.3
10.7
8.7
7.6
0
1990 2020 2050 2075 2100
Year
Average winter minimum temperatures Average summer maximum temperatures
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 19Sunshine Coast Climate Change Background Study
4.1 (f) Extreme temperatures
The proportion of days per year with temperatures above 35°C is projected to increase (Figure
4.5).
Compared to 1990 temperatures, the Sunshine Coast is expected to experience:
Ź An additional 7 days (1 week) of extreme temperatures by 2050,
Ź At least an additional 14 days (2 weeks) of extreme temperatures by 2075; and
Ź An additional 30 days (1 month) of extreme temperatures by 2100.
Figure 4.5: The projected worst case change in the average number of days per annum where temperatures
will be greater than 35°C. (Projections are for the period from 1990 to 2100. In accordance with climatology
standards the average has been calculated using 30 years of projected data). (Model settings: HadCM GCM
with high sensitivity and IPCC SRES A1T scenario for 2020 and IPCC SRES A1FI for 2050, 2075 and 2100)
40
Average Number of Days per
34
Annum Above 35°C
30
28
20
20
10
10 5 15
4
2 4 7
0
1990 2020 2050 2075 2100
Years
Tewantin Post Office Nambour Dept Primary Industries Crohamhurst
These projected heat extremes indicate a higher potential for heat waves and droughts which will
impact on the lifestyles and livelihoods of the Sunshine Coast population.
4.1 (g) Implications of shifts in minimum temperatures
While higher minimum winter temperatures are likely to have positive implications for sectors such as
recreation and tourism, the implications are adverse for aspects of the natural environment and the
agricultural sector. Natural plant cycles are expected to be impacted presenting challenges for
industries such as wine which relies on frosts for crop development.
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Shifts in summer minimum temperatures will also impact on liveability for natural and human
environments, particularly as the region will experience warmer minimum temperatures at night. In an
urban context, there will be less relief from higher daytime temperatures, particularly during heat
waves.
4.1 (h) Implications of shifts in maximum temperatures
Shifts in summer maximum temperatures will also impact both natural and human environments.
Higher maximum summer temperatures have a potential to put stress on sectors such as recreation
and tourism as people become more concerned about health risks associated with warmer weather.
In an urban context, household disposable income may decline with increased demand for air
conditioning or alternative places of refuge may be required during heat waves.
4.2 Rainfall
The Sunshine Coast is expected to experience a change in rainfall patterns as a result of climate
change. These include:
Ź Reductions in annual rainfall
Ź Fewer days per annum when rainfall can be expected to occur
Ź Shifts in mean seasonal rainfall
Ź Shifts in mean monthly rainfall
Ź Changes in the intensity and frequency of extreme rainfall events.
4.2 (a) Historic changes in annual mean rainfall for the Sunshine Coast
Based on analysis of observational data, the IPCC (IPCC 2007) has identified that there is evidence
of decreasing rainfall across the globe. For SEQ, the average annual rainfall in the last decade fell
nearly 16 per cent compared with the previous 30 years. This is generally consistent with natural
variability experienced over the last 110 years, which makes it difficult to detect any influence of
climate change at this stage.
A simplified analysis of data from a number of weather stations on the Sunshine Coast appears to
support the IPCC statement as, in general terms, the local data indicates that total annual rainfall has
changed over time (Figure 4.6). For the period between 1888 and 1960 there is a trend of increasing
annual rainfall. For the IPCC baseline period between 1961 and 1990 the trend changes and shows a
decline in annual rainfall. For the period between 1991 and 2006, the trend of decreasing annual
rainfall appears to accelerate.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 21Sunshine Coast Climate Change Background Study
Figure 4.6: Scatter plot of annual total rainfall for the Sunshine Coast for the periods 1888 to 1960 (blue dots),
1961 to 1990 (light blue dots) and 1991 to 2006 (green dots) and a line of best fit for each period (green, blue
and grey respectively. The scatter plot is based on aggregation of daily rainfall data to obtain annual total
rainfall from 30 monitoring sites across the Sunshine Coast. Tthe trend of declining rainfall is apparent.
5000
4000
Annual Rainfall (mm)
3000
2000
1000
0
1885 1905 1925 1945 1965 1985 2005
Year
Pre 1961 1961-1990 Post 1990
(The period 1961 to 1990 was selected as this is consistent with the baseline periods assessed by the IPCC (IPCC 2007).
Annual means were excluded where missing data in that year exceeded 150 days. This removed a potential for distortion of
the trend lines due to the inclusion of abnormally low annual means which were not related to the actual rainfall which
occurred in that year. Missing data for other years was assumed to be zero. El Nino and other factors of climatic variability
have not been considered in this analysis. Source: Bureau of Meteorology data for daily rainfall contained in SimCLIM.
Rainfall data was available for the following weather stations: Tewantin Post Office, Pomona Post Office, Beerburrum
Forest Station, Cooroy Composite, Beerwah Forest, Peachester Woodford, Crohamhurst, Bald Knob, Landsborough Post
Office, Caloundra Post Office, Caloundra Signal Station, Caloundra Water Treatment Plant, Maleny Dening Road,
Mooloolah Post Office, Buderim Post Office, Palmwoods Hobson St, Craglands, Kenilworth Township, Little Yabba SFR
274, Nambour DPI, Mapleton Post Office, Moreton Sugar Mill, Nambour Bowling Club, Yandina Post Office, Conondale
Township, Coolum Bowls Club, Eumundi Crescent Rd, Imbil Post Office, Kin Kin Post Office and Maleny Tamarind St.)
4.2 (b) Changes in annual mean rainfall for the Sunshine Coast
Rainfall is projected to decline across the Sunshine Coast consistent with the CSIRO (2007a)
projections for changes in rainfall for SEQ. The ‘best estimate’ of projected rainfall change shows a
decrease under all emissions scenarios. However, there is considerable variability between the
projected a range of rainfall changes for the different GCMs.
Projections also indicate annual potential evaporation could increase 6–16 per cent by 2070.
Through analysis of historic records for catchments east of the Great Dividing Range, Miles et. al.
(2008) have identified that a 25 per cent reduction in long term rainfall is likely to result in reductions
in stream discharges of up to 50 per cent. As a result, a likely reduction in rainfall on the Sunshine
Coast would indicate a significant reduction in available water resources in the region by 2100.
These reductions in available water resources may occur over much shorter time frames than those
suggested, as the future climate could be drier and hotter than the climate evaluated by Miles et. al.
(2008).
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 22Sunshine Coast Climate Change Background Study
The decline in water resources is also likely to be exacerbated by high population growth in the
region.
4.2 (c) Changes in mean seasonal rainfall
The Sunshine Coast is likely to experience seasonal shifts in rainfall patterns. While the shift for
winter is unclear as different models suggest either an increase or decrease, the overall trend for
projected rainfall patterns is a decline and, if so, this is likely to impact on water supply, agriculture
and industry.
Table 4.1 indicates the projected seasonal changes in rainfall. Seasonal changes in rainfall are
expected to have limited impact on the short term availability of water resources on the Sunshine
Coast. In the medium to long term, however, there is potential for the Sunshine Coast to rely on
summer rainfalls (particularly in January and February) and increased, but limited winter rainfalls.
Table 4.1: Comparison of the relative temporal variation in seasonal rainfall for the Sunshine Coast
Season Time Frame Projected Outcome
Summer 2020 Decrease in rainfall
2100 Further decrease in rainfall
Autumn 2020 Decrease in rainfall
2100 Further decrease in rainfall
Winter 2020 Shift in rainfall
2100 Further shift in rainfall
Spring 2020 Decrease in rainfall
2100 Further decrease in rainfall
4.2 (d) Changes in mean monthly rainfall
Mean monthly rainfall represents the average rainfall received for each particular month, based on
analysis of a 30 year data set. Figure 4.7 shows the current and projected monthly means for the
Nambour Department of Primary Industries (DPI) weather station. The current monthly means follow
a cyclic process with high monthly rainfall associated with summer and early autumn, declines in
monthly rainfall until late winter or early spring, followed by higher monthly rainfall in late spring and
early summer. While there is local variability, other weather stations on the Sunshine Coast show
similar results.
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 23Sunshine Coast Climate Change Background Study
Figure 4.7: Long-term (30 year) mean monthly rainfall graphs for current (1961 – 1990) and projected climates (2025, 2050 and 2075) for the
Nambour DPI weather stations. (The numbers on the X axis represent the months of the year from 1 to 12.) (Source: SimCLIM model using
HADCM3 GCM with high sensitivity and IPCC SRES A1FI Scenario. The rainfall characteristics are a probability density function based on a 30 year
data set. It should be noted that projections using other GCMs may produce different results to those displayed)
Current 2025
2050 2075
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 24Sunshine Coast Climate Change Background Study
As indicated in Figure 4.7, characteristics of monthly rainfalls are expected to be increasingly impacted
by climate change over time. There is likely to be significant reliance on January and February
rainfalls to replenish the region’s water resources.
While further investigation is required, it is expected that these projected shifts in the characteristics of
monthly rainfalls will impact environmental flows, ecology and water resource extraction in the
catchment.
4.2 (e) Rainfall intensity and flooding
It is projected that climate change will impact on the frequency and intensity of extreme rainfall events,
with fewer but larger rainfall events expected, consistent with CSIRO projections (Abbs, McInnes and
Rafter 2007).
This is supported by Queensland Transport’s ‘Sunshine Coast Multimodal Transport report’ (Main Roads
2009) which indicates that “an analysis of CSIRO studies on climate change indicates a potential for a 32
per cent increase in rainfall intensity in the Sunshine Coast due to climate change”.
To provide an indication of this change, the SimCLIM model has been used to undertake a statistical
analysis of historical daily rainfall data from the weather stations at Crohamhurst, the Department of
Primary Industries Research Centre in Nambour (Nambour DPI) and the Kin Kin Post Office (Table 4.2).
The change in the intensity of rainfall events is provided using estimated recurrence periods for historic
and projected rainfall events. The recurrence period is an estimate of the probability that a given rainfall
event would be equalled or exceeded in any given year. This example has focused on the rainfall event
which could be expected to occur once every 100 years.
Table 4.2 The current 1-in-100 year, 24 hour rainfall event for selected weather stations on the Sunshine Coast,
and the projected recurrence period for the same size event for four future time frames (Source: SimCLIM model
using HADCM3 GCM with high sensitivity and IPCC SRES A1T Scenario for 2020 and IPCC SRES A1FI Scenario
for 2050 2075 and 2100. The projected rainfall is based on a 30 year data set.)
Historic 1-in-100 year Projected return period for the rainfall event equivalent
Weather Station
rainfall event (24 hour) to the historic 1-in-100 year event
Size (mm) 2020 2050 2075 2100
Crohamhurst 602.87 100 years 86 years 60 years 44 years
Nambour DPI* 514.96 88 years 69 years 50 years 37 years
Kin Kin 392.35 98 years 75 years 43 years 28 years
* Department of Primary Industries Research Centre
# Based on daily rainfall records for: Crohamhust 01/01/1893 to 31/12/2003, Nambour DPI 1/01/1952 to 31/12/2007 and
Kin Kin Post Office 1/01/1969 to 31/12/2000. These data sets do not include records for the recent flood events which
occurred in 2009.
As a result of climate change, rainfall events which are the same size as the historic 1-in-100 year
rainfall event are expected to occur more frequently in the future. In addition to the potential for more
frequent flooding, this shift in the characteristics of rainfall events is also likely to:
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 25Sunshine Coast Climate Change Background Study
Ź Increase runoff and associated pollutants
Ź Increase soil erosion
Ź Impact on vegetation cover which provides soil stability.
These shifts in environmental flows and water quality are expected to impact on waterways and
biodiversity.
4.3 Sea level rise
Future sea level rise is usually discussed with regard to changes in mean global sea level (IPCC 2007,
IPCC 2001, Hunter 2009). However, sea level varies regionally, so local variations should be a
consideration when determining the implications of sea level rise (Maunsell Australia 2008, ACE CRC
2008, Church et. al. 2008b). In addition, planning considerations need to address changes in mean sea
level and the implications this has for shifts in tidal extremes and storm surge (eg higher spring tides will
create new risk areas and increase the incidence of coastal inundation and erosion) (ACE CRC 2008,
Hunter 2008a).
The integration of local and regional considerations into sea level rise hazard analysis is not always
practical due to data limitations. For example, assessments of existing coastal processes may not be
available or localised projections of sea level rise may not have been undertaken. In many cases, this
will require sea level rise hazard analysis to be undertaken using alternative indicators such as projected
averages for global sea level rise or broad default values for extreme tides and storm surges.
4.3 (a) Measured global sea level rise
The rate of global sea-level rise from the 19th to the 20th century averaged about 1.7 mm/year (Church
et. al. 2008a).
While it has not been directly attributed to climate change at this time, the average rate of global sea-
level rise increased from 1.8 mm/year for the period 1961 to 2003 to 3.1 mm/year for the period 1993 to
2003 (IPCC 2007).
This is not unprecedented. At the peak of the last ice age, 21,000 years ago the “sea level rose by as
much as 4 m per century as the climate warmed and land-based ice melted and drained into the ocean”
(Church et. al. 2008a).
Paleological records indicate that, about 125,000 years ago, this resulted in sea levels 4–6 m above
those of the present day (Church et. al. 2008a).
Sunshine Coast Climate Change and Peak Oil Strategy 2010 – 2020 Page 26Sunshine Coast Climate Change Background Study
4.3 (b) Projected mean sea level rise
A range of scientific projections have been developed regarding sea level rise:
Ź The IPCC Third Assessment Report (TAR) indicates that, by 2100, the global mean sea level rise
can be expected to be between 8cm and 88 cm (IPCC 2001)
Ź The IPCC Fourth Assessment Report (AR4) indicates that, by 2100, the upper limits for sea level rise
are equivalent to the upper limits of the range identified in the TAR, while the lower limits of the AR4
projections are higher than the TAR levels (Hunter 2008b, IPCC 2001, IPCC 2007)
Ź The Queensland Government has adopted a series of planning levels for sea level rise in the Draft
Queensland Coastal Plan (DERM 2009). These appear to reflect the projections of Hunter (2008b)
for the 95th percentile for the A1FI SRES Scenario.
Ź The Australian Government Department of Climate Change (AGDCC 2009) report ‘Climate change
risks to Australia’s Coast – A First Pass National Assessment’ indicates that global mean sea level
rise is projected to be 110 cm by 2100 (Table 2.1 pp 27). Projections of 20 cm and 70 cm are also
provided for 2030 and 2070 respectively. This report was released on 14 November 2009.
Ź Estimates recently published in the journal Science consider the constraints on glacial melt and state,
‘we consider glaciological conditions required for large sea-level rise to occur by 2100 and conclude
that increases in excess of 2 metres are physically untenable.’ However, there is a body of literature
which suggests that sea level rise of greater than 2 metres by 2100 cannot be ruled out entirely.
These largest of sea level rise scenarios are termed the H+ scenarios and are generally derived from
models projecting the greatest changes based on observations of past sea level from periods
analogous to the 21st century (Table 2). These scenarios have a very low probability of occurring by
2100.
There are some key elements to note with regard to the projections which were utilised for the
assessment which is reported in the ‘First Pass National Assessment’ (AGDCC 2009):
Ź New research using statistical approaches informed by the observed relationship between
temperature and sea level has resulted in updated sea level rise projections (Rahmstorf 2007). Sea-
level rise projections presented to the March 2009 Climate Change Global Risks, Challenges and
Decisions Congress in Copenhagen ranged from 0.75 to 1.9 metres by 2100 relative to 1990, with
1.1–1.2 metres the mid-range of the projection (AGDCC 2009, Rahmstorf 2009).
Ź The ‘high end’ scenario that was utilised in the Department of Climate Change assessment
“considers the possible high-end risk identified in AR4” and “includes some new evidence on
icesheet dynamics published since 2006 and after AR4”
Ź A sea-level rise value of 1.1 metres by 2100 was selected in the Department of Climate Change
assessment as it represented a plausible range of sea level rise values from post IPCC research
(AGDCC 2009). In particular the citation in the First Pass National risk assessment refers to
Rahmstorf (2009) and the associated presentation at the Copenhagen Climate Change Congress in
Copenhagen March 2009 (AGDCC 2009)
Ź The basis for utilising the ‘high end’ scenario was that “post AR4 analysis combining thermal
expansion and potential rates of ice melt show that the probabilistic distribution is skewed towards
the upper end and that using the high-end scenario to inform decision-making is justified”
Ź The Department of Climate Change report has recognised the value of the ‘high end’ scenario as a
decision making tool (AGDCC 2009)
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