City of Greater Geelong and Wyndham City Council
29-Jul-2013
Urban Heat Island Report:
City of Greater Geelong and
Wyndham City Council
Urban Heat Island Report
Client: City of Greater Geelong and Wyndham City Council
ABN: 38 393 903 860
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City of Greater Geelong and Wyndham City Council
Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
Quality Information
Document
Urban Heat Island Report
Ref
60299326
Date
29-Jul-2013
Prepared by
Peter Steele
Reviewed by
Ben Smith
Revision History
Authorised
Revision
Date
Details
Revision 1
27-Jun-2013
Draft for review
Revision 2
29-Jul-2013
Final
Revision
Name/Position
Ben Smith
Team Leader –
Sustainability and
Climate Change
Ben Smith
Team Leader Sustainability and
Climate Change
29-Jul-2013
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Signature
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City of Greater Geelong and Wyndham City Council
Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
Table of Contents
Urban Heat Island Report
Executive Summary
1.0
Project context
2.0
What is the urban heat island (UHI)?
2.1
Urban heat island or urban heat?
2.2
Surface temperature versus air temperature
3.0
Urban heat risks
3.1
Overview of urban heat risks
3.2
Heat effects
3.2.1
City of Greater Geelong
3.2.2
City of Wyndham
3.3
Activities
3.3.1
City of Greater Geelong
3.3.2
Wyndham City Council
3.4
Vulnerability
3.4.1
City of Greater Geelong
3.4.2
City of Wyndham
3.5
Potential impact from climate change
3.5.1
City of Greater Geelong (Corangamite Region)
3.5.2
Wyndham City Council (Port Phillip and Westernport Region)
3.5.3
Potential impact of climate change on urban heat
4.0
Responding to UHI risks
4.1
Practical mitigation responses
4.2
Plan making
4.2.1
City of Greater Geelong
4.2.2
City of Wyndham
4.3
Operations / implementation
4.3.1
City of Greater Geelong
4.3.2
City of Wyndham
5.0
Limitations and next steps
5.1.1
Limitations
5.1.2
Further work
6.0
References
Appendix A
Appendix B
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City of Greater Geelong and Wyndham City Council
Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
5
Executive Summary
The Urban Heat Island effect (UHI), and urban heat more broadly, has a range of potential impacts on health,
infrastructure and resource consumption. This report, commissioned by the City of Greater Geelong (CoGG) and
Wyndham City Council (WCC), explores the characteristics of urban heat for these two municipalities, utilising
data collected using airborne thermal sensing equipment.
The literature review undertaken for the project found a diverse range of academic research, government-oriented
discussion papers and toolkits focused on urban heat. It highlighted that urban heat can present a range of social,
economic and environmental risks and is likely to be further exacerbated by projected climate change. Relevant
literature also provided analysis of the various mitigation measures that may be used to reduce the extent and
impact of urban heat.
Context is critical in considering urban heat and possible mitigation strategies. Our analysis of vulnerability to
urban heat in the CoGG and WCC municipalities examined current and future urban form, delivery of core Council
services, and the impact of policies and strategies. Broad scale analysis using the available thermal sensor data
showed that both municipalities are affected by urban heat. Areas where a higher proportion of surfaces are
covered by built form showed higher surface temperatures, and the impact of green spaces, irrigated grass and
lighter coloured materials was also evident through lower surface temperature readings. The report also highlights
the potential for urban heat to impact on a broad range of Council facilities and services, and that vulnerable
segments of the community, including the elderly and disabled, may experience more severe impacts.
To derive the greatest value from the innovative thermal data available to CoGG and WCC, and to better respond
to urban heat risks, a range of potential responses have been identified for each municipality. The responses are
necessarily high level, and will rely on further work and consideration by CoGG and WCC and consultation with
relevant external stakeholders. Importantly, however, the responses recognise the importance of urban heat risks
being considered across Council, and not being seen as an issue restricted to the Environment or Sustainability
areas of local government.
The priority actions for CoGG and WCC identified through this process include:
-
Plan making: identify short term opportunities for urban heat risks to be considered in new plans related to
urban development, risk, health and wellbeing, capital works, and parks and open space.
-
Practical guidance: develop practical guidance for Council capital works and external developers, to inform
urban design, landscaping and built form decision-making.
-
Lead by example: explore opportunities for a practical retrofit pilot to be undertaken on a Council-owned
facility, utilising a combination of built form and landscaping approaches to demonstrate the potential for
local urban heat impacts to be reduced.
-
Improve data: consider the initiation of a structured monitoring program, using more readily and cheaply
available LANDSAT data, to further explore the characteristics of urban heat for each municipality and
inform mitigation efforts.
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Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
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Project context
City of Greater Geelong (CoGG) and Wyndham City Council (WCC) have jointly commissioned AECOM and
Monash University to provide this executive report to assist in communicating the risks from urban heat island,
and to set out the responses that are available in each of the local government areas (LGA’s) to mitigate these
risks.
The report is informed by a brief literature review, a review of climate change projections for Victoria and analysis
of airborne thermal remote sensing that was undertaken independently for WCC and CoGG on 24 January 2012
and 6 February 2013 respectively. See Appendix B for an overview of the thermal data collected.
The next steps for both councils in responding to this risk will be different. Given this, the report is structured to
provide both councils with content that is specifically relevant for their LGA, and which can be used to inform
further engagement, future work and strategy development.
2.0
What is the urban heat island (UHI)?
Urban development replaces natural surfaces and vegetation with the dry, hard surfaces and structures of roads,
footpaths and buildings. On sunny days, these surfaces accumulate and store solar heat energy. They are also
impervious meaning that when it rains the water drains away rapidly leaving little moisture in the ground layer and
consequently reducing evapotranspirative cooling. In addition to this, the height and form of high-density
development can trap heat at night. The combination of these factors, as well as other sources of heat in the
urban environment such as air conditioners and vehicle engines, often leads to warmer air temperatures in urban
areas than in the surrounding rural areas. This is particularly noticeable at night, when heat that is stored in the
urban landscape is slowly released, increasing the temperature differential between urban and rural areas. This is
referred to as the Urban Heat Island effect (UHI), which is generally considered the measure of this difference in
air temperatures between urban and rural areas. Local and international studies have found that the UHI effect
can add between 1°C to 6°C to ambient air temperature and is likely to be further exacerbated by climate change.
2.1
Urban heat island or urban heat?
There is an important distinction to be noted between UHI and a broader concept of urban heat. UHI refers
specifically to the difference between urban and rural temperatures, and is also often focused on night time
temperature differences. Urban heat, however, is a broader concept referring to the heat impacts associated with
urban environments. For the purposes of this study, UHI is less relevant than the identification, impact and
response to urban heat. As a result, the focus of the report will not be on the difference between rural and urban
temperatures, but the impact of, and response to, urban heat more broadly.
2.2
Surface temperature versus air temperature
Discussion of urban heat can be usefully separated into air temperature and surface temperature. Air temperature
urban heat is more commonly discussed, often in the context of urban areas having a higher air temperature at
night when compared surrounding rural areas. Air temperature can be impacted by a range of factors, for example
prevailing winds, proximity to the ocean and local meteorological conditions. Surface urban heat is a key
contributor to air temperature, and can be addressed through a range of mitigation measures. Importantly for this
study, the thermal imagery that is being analysed represents surface temperature as opposed to air temperature.
As a result, any discussion of future impacts and possible mitigation strategies is related primarily to surface
temperature. It should be noted that projections for temperature changes relating to climate change are based on
air temperature.
Figure 1 on the next page highlights this distinction as well as additional delineations that can be made in
assessing urban heat.
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Figure 1: Surface and air temperatures vary over different land use areas. Surface temperatures vary more than air temperatures during
the day, but they both are fairly similar at night. The dip and spike in surface temperatures over the pond show how water maintains a
fairly constant temperature day and night, due to its high heat capacity (US EPA, http://www.epa.gov/heatisland/about/index.htm)
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3.0
Urban heat risks
3.1
Overview of urban heat risks
8
Where and to what extent urban heat occurs is the result of a wide variety of interacting factors. These include
building density, height, surface permeability, presence or absence of plants and trees, surface materials, surface
colours and meteorological conditions. Localised impacts, particularly related to surface urban heat, are
influenced by the specific characteristics of the surrounding urban environment.
Potential impacts associated with urban heat include:
-heat stress, leading to illness and mortality for humans and animals
-increased water use (irrigation, evaporative air conditioning)
-increased energy consumption (for air-conditioning or increased use of motorised transport)
-infrastructure failure (transport, electricity distribution).
Generally speaking, the risks are greatest when high activity areas with vulnerable populations are subject to
extreme heat, as depicted in Figure 2 below.
C
Exposure of the
population
Heat
B
Vulnerability A
B
Activity
B
A = Highest priority
C
C
B = Medium priority
C = Moderate priority
Figure 2: Diagram representing factors required to identify areas of high (A), medium (B) and moderate (C) priority for UGI
implementation for surface temperature heat mitigation. The key factors are daytime surface temperatures (Heat) and areas of high
activity (Activity), which combined indicate areas of high exposure. In addition, areas with high concentrations of vulnerable population
groups (Vulnerability) should be identified (Norton et al 2013).
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3.2
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Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
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Heat effects
The Western Melbourne region, which includes Wyndham City Council and City of Greater Geelong, has a
diverse range of urban environments. These include large, low-density, single use residential growth areas,
established residential suburbs, dense mixed use and commercial areas, and industrial precincts. The urban heat
risks to each of these urban environments are different and locally specific, and influenced by a range of factors.
Figure 3: Land surface temperatures observed from MODIS satellite imagery on 28-29 Jan 2009 for daytime (left) and night time (right)
(Loughnan et al. 2010)
Thermal imagery has been reviewed for this study. A number of specific heat effects and suggested approaches
for mitigation, based on the thermal imagery are set out in the sections below. The thermal flyover for Geelong
was undertaken on 6 February 2013 and for Wyndham on 24 January 2012. Limitations in respect of the thermal
data are set out in 5.1.1 however the imagery provides a good way to better understand a range of risks and to
begin to consider appropriate responses.
3.2.1
Table 1
City of Greater Geelong
Urban heat risks and potential responses based on thermal imagery data collected on 6 February 2013
Street scene

A comparison of two streets is presented below, one with trees (northern east-west street) and one without
(southern east-west street). The cooling nature of the street trees is evident.

However, these street are designed for different purposes: the open street is for traffic, while the street with
trees is designed for parking and pedestrians.
Location: 118-136 Little Malop St, Geelong
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Car parks


Unshaded car parks show high surface temperatures. Planting trees within the car park would be beneficial.
This car park is close to the ocean, and there is likely to be sea breezes providing cooling effects despite the
high surface temperatures. However, trees provide shading as well, which is important for improving human
thermal comfort.
Location: Deakin University car park 68-92 Cavendish St, Geelong
Hot spots and mapping anomalies

Data can be used to identify hotspots surrounding areas with populations that are vulnerable to heat such as
schools. The asphalt car park is a hot-spot, as is the unirrigated grass area. The effect of irrigation can be
seen in the area to the east of the shade sails.

The very cold (blue) roof is an artefact of the data collection process and is due to the low emissivity.

The surrounding wide roads could also be targeted for vegetation to reduce surface heating.
Location: 275 Moorabool St, Geelong
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The block below is particularly devoid of vegetation and has a very high level of imperviousness, and shows
very high ground level surface temperatures. This would be classed as a ‘hot-spot’.
Location: 31 Little Ryrie St, Geelong
Public open space

Public open space can be irrigated to provide a more thermally comfortable environment. The surface here
(dark tan bark) actually serves to increase the surface temperature and surfaces are as hot as the
surrounding asphalt roads. This park does provide tree shade however, which is beneficial for human
thermal comfort.
Location:160-166 McKillop St, Geelong



Some of the hottest areas during the day are wide open streets where there is little shading from buildings or
vegetation.
High amounts of solar radiation reach the surface here, resulting in intense heating.
Vegetation is most effective during the day in wide open streets where solar access is high.
Location: 16 Sydney Ave, Geelong
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Soil moisture

The role of soil moisture can also be seen in this image. Along the river, and the depression on the west of
the image, grass surface temperatures are lower as moisture drains to these areas.
Location: La Trobe Terrace, Belmont
Building shade

The colour palette has been changed in this image to emphasise the effects of building shade on surface
temperatures. Surface temperatures were some 25 degrees cooler when shaded. Of course, this shade will
move throughout the day, but in designing streets for pedestrians and public space, solar access should be
considered.

Shading patterns in the thermal image are slightly different form the aerial image because of the different
times of the day.
Location: 4 Corio St, Geelong
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Tree shade


Again to emphasise the cooling effect the colour palette was changed. In the image below the tree canopy
temperature is lower than surrounding urban materials because trees absorb and reflect solar energy, and
also transpire. Plus, the shading effect of this large canopy tree can be seen. Large shade trees should be
protected and promoted.
Again, shade patterns will change throughout the day, so designing spaces should consider solar access
and strategically place trees
Location: 283 Ryrie St, Geelong

In another example to emphasis tree effects: the tree canopy temperatures in the irrigated park appear
cooler than in the adjacent park to the south-east. This could possibly be due to the different amounts of
irrigation in the parks (it could also be a result of different tree species)

Irrigation provides more moisture to the root zone for trees to draw on for photosynthesis and transpiration.

Tree canopy temperatures did vary and this can also be a result of the micro-climate these trees are
exposed to. Trees surrounded by urban surfaces must endure higher surface temperatures (from the ground
and walls) and warmer, drier conditions. Providing soil moisture can help trees endure urban conditions.
Location: 6 Bellerine St
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3.2.2
Table 2
City of Greater Geelong and Wyndham City Council
Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
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City of Wyndham
Urban heat risks and potential responses based on thermal imagery data collected on 24 January 2012
Hot spots and mapping anomalies

Some rooftops appear very cold such shopping complexes and some industrial areas. These surface
temperatures are very difficult to interpret. While the light colour of the roof will reflect more solar radiation,
these cold roofs are also an artefact of the data collection approach. Remote sensing does not account for
the emissivity of the surface (emissivity is the ability of a surface to emit radiation). Materials like corrugated
iron have low emissivity, and hence appear cold. It is very difficult to account for emissivity and these
rooftops should be excluded from analysis. These roofs could be underestimated by anywhere between 20
and 40°C.

Despite the apparent cool temperatures, this is a priority area because of high pedestrian activity. The
buildings will provide some shading during the day, but more vegetation and water availability could improve
the micro-climate here during the day.
Location: 4 Main St, Point Cook

Very dry, barren areas show surface temperatures that are high during the day, and a similar temperature to
urban surfaces.

One difference, however, is that these barren surfaces will actually cool rapidly at night, while the urban
surfaces will remain warm.

Dry, barren surfaces will hinder daytime thermal comfort. Vegetation and irrigation can mitigate this.
Location: Boardwalk Boulevard, Point Cook
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The light coloured roof in the image below is around 6°C cooler than surrounding rooftops. The high
reflectivity of the roof would contribute to reduced atmospheric heating. It would also be likely to have
building energy efficiency benefits. Products are available in the market such as ThermoShield which
provide highly reflective ceramic paints that are designed to reflect across the entire shortwave spectrum.
Paints are available in other colours, and represent a relatively inexpensive mitigation action with potential
for widespread uptake.
Location: 27 Peppertree Dr, Point Cook
Soil moisture

The effects of irrigation can be clearly seen. This irrigated oval (~32°) is around 12-13°C cooler than
surrounding unirrigated ground cover (~45°C).

Increasing soil moisture reduces surface temperatures during the day. It can slow surface cooling marginally
at night, meaning these surfaces will still be cooler than urban surfaces. The overall effect of irrigation on
surface temperature is a net benefit.
Location: 19 Kingsley Ave, Point Cook

In contrast with the irrigated oval, at Emmanuel College (above), these are synthetic turf basketball courts
which show temperatures of 48-49°C. This space is designed for school children physical activity and would
deliver a warmer and higher radiative environment than irrigated sports-fields.
Location: 2-40 Foxwood Dr, Point Cook (overleaf)
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Evapo-transpiration cooling

The tops of these trees are much cooler during the day. They provide shading and transpirational cooling.
As this image was taken at solar noon, shading effects of trees on surrounding surfaces can’t be seen.
Location: 17 Wattle Grove, Point Cook
Public open space
Public space. In the hottest area of this public space is a playground. Public space should be designed to
minimise exposure to extreme heat. Irrigated vegetation can provide a more comfortable thermal environment, as
well as improve amenity.
Location: 20 Sidney Nolan Walk, Point Cook
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Water bodies
Obviously, water bodies are much cooler during the day due to evaporation of water and a high thermal mass.
This higher thermal mass means that at night, surface temperatures can be relatively warm, but surfaces may still
be evaporating so providing cooling. Night time surface temperatures of water will still be cooler than urban
surfaces on hot nights. Strategically placed water bodies, or water sensitive urban design measures that retain
water in the landscape, can be used to provide local cooling.
Location: 64 Scrubwren Dr, Williams Landing
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3.3
Activities
3.3.1
City of Greater Geelong
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Council facilities and services
CoGG owns approximately 700 facilities across the municipality, varying from significant office buildings to parks
to toilet blocks. A selection of CoGG facilities is shown in Figure 4 on the next page. When compared with the
thermal data, shown in Appendix B, it can be seen that Council facilities are located in a range of urban
environments and are likely to experience varying degrees of urban heat. While more detailed analysis is required
to determine the relationship between CoGG facilities and localised urban heat, the analysis in Section 3.2
highlights the potential impact of a range of urban environments including streets, buildings, ovals and
playgrounds.
In addition to owning and managing physical assets, Council employees deliver a range of services that include
community support and outreach, management of recreation facilities, waste management and administration of
local laws.
Urban heat poses a range of potential risks to CoGG that relate to both physical assets and service delivery. In
addition, Council’s assets also have the potential to increase urban heat impacts. Potential risks include:
-
heat stress to Council employees required to work outdoors (e.g. maintenance staff at recreation facilities,
community outreach workers)
-
increased operating costs for Council buildings due to increased electricity consumption for air conditioning
-
reduced amenity of Council-owned recreation facilities, such as playgrounds
-
increased demand for community support for vulnerable residents during periods of extreme heat
(exacerbated by urban heat impacts).
New urban development
The population of CoGG is growing and to support this growth significant additional urban development will
continue to occur. The number of private dwellings in the municipality is predicted to increase from approximately
101,000 in 2013 to 134,000 in 2031 (Forecast.id 2011b), and the majority of this increase will occur in growth
areas such as Armstrong Creek. In many cases this growth will result in vegetated, non-urban environments being
replaced by the hard surfaces and materials that are associated with urban heat impacts. Figure 4 on the
following page shows the arrangement of existing land uses across the municipality, and highlights the Armstrong
Creek growth area.
CoGG has the capacity to influence the location and type of development that occurs through strategic and
statutory planning tools. While there are limits to the requirements that Council can make of developers, there are
a range of potential urban heat mitigation measures that can be pursued through this process to reduce the
likelihood and impact of urban heat on future development.
Potential urban heat risks posed to new urban growth include:
-
health and wellbeing impact on future residents, particularly vulnerable groups (e.g. elderly, disabled)
-
increase in living expenses due to increased reliance on air conditioning and private vehicle transport
-
increase in social isolation
-
increase in urban heat impacts on surrounding areas.
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Figure 4 CoGG land uses, key growth area and selected Council facilities (ABS data composite including planning zones)
1 - Ocean Grove Library & Shopfront
2 - Geelong West Town Hall
3 - Bellarine Multi Arts Centre
4 - Bellarine Aquatic Sports Centre
5 - City Hall
6 - Civic Centre Car Park
7 - Queens Park Golf Club & Kiosk
8 - Corio Leisure Time Centre
9 - City works (Corio)
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3.3.2
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Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
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Wyndham City Council
Council facilities and services
WCC owns approximately 800 facilities across the municipality, varying from significant office buildings to parks to
small buildings such as toilet blocks. Around 150 of these facilities are buildings, and the municipality is also
responsible for 40 significant parts and sporting reserves. In addition to owning and managing physical assets,
Council employees deliver a range of services that include community support and outreach, management of
recreation facilities, waste management and administration of local laws.
Urban heat poses a range of potential risks to WCC that relate to both physical assets and service delivery. In
addition to being impacted by urban heat, Council’s assets also have the potential to increase urban heat impacts.
Potential risks include:
-
heat stress to Council employees required to work outdoors (e.g. maintenance staff at recreation facilities,
community outreach workers)
-
increased operating costs for Council buildings due to increased electricity consumption for air conditioning
-
reduced amenity of Council-owned recreation facilities, such as playgrounds
-
increased demand for community support for vulnerable residents during periods of extreme heat
(exacerbated by urban heat impacts).
New urban development
WCC is one of Victoria’s fastest growing local government areas, and to support this rapid growth significant
additional urban development will continue to occur. The number of private dwellings in the municipality is
predicted to increase from approximately 70,000 in 2013 to 124,000 in 2031 (Forecast.id 2011a), and the majority
of this increase will occur in new growth areas such as Ballan Road and Westbrook. In many cases this growth
will result in vegetated, non-urban environments being replaced by the hard surfaces and materials that are
associated with urban heat impacts. Figure 5 on the following page identifies a number of significant growth areas
in the municipality. These are areas where urban heat risks may increase as development occurs, however also
represent opportunities to implement urban heat mitigation strategies.
WCC has the capacity to influence the location and type of development that occurs through strategic and
statutory planning tools. While there are limits to the requirements that Council can make of developers, there are
a range of potential urban heat mitigation measures that can be pursued through this process to reduce the
likelihood and impact of urban heat on future development. These are explored in Section 4.0 of this report.
Potential urban heat risks posed to new urban growth include:
-
health and wellbeing impact on future residents, particularly vulnerable groups (e.g. elderly, disabled)
-
increase in living expenses due to increased reliance on air conditioning and private vehicle transport
-
increase in social isolation
-
increase in urban heat impacts on surrounding areas.
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Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
Figure 5 WCC land uses, key growth areas and selected Council facilities (ABS data composite including planning zones)
1 - Wyndham City Council
2 - Hoppers Crossing Youth Resource Centre
3 - Wyndham Leisure & Events Centre
4 - Wyndham Cultural Centre
5 - Point Cook Learning Centre
6 - Werribee South Caravan Park
7 - Chirnside Park
8 - Manor Lakes Community Learning Centre
9 - Saltwater Reserve
10 - Jamieson Way Community Centre
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The effects of urban development on land surface temperature can be seen below in Figure 6. While it is
important to recognise the numerous variables that influence the individual temperature readings of these images,
the broad pattern of urban development over time, and the impact of this on surface temperature reading, is
instructive when considering the influence of built form on urban heat.
Figure 6 LANDSAT land surface temperature image (average of 7 images from 1999-2005: Nury et al. 2012) and right: LANDSAT image with Wyndham
thermal flyover overlaid (30m resolution) for 2012.
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3.4
City of Greater Geelong and Wyndham City Council
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Vulnerability
Research has identified the increased risk posed by urban heat to vulnerable populations, including the elderly
and those suffering chronic illness and disability (Loughnan et al 2013). Urban heat may also have a greater
impact on low income households due to the potential impact on living costs. The ABS provides an indicator of
socio-economic vulnerability called Socio-Economic Indexes for Areas (SEIFA), which can be used to identify the
geographic spread of socio-economic vulnerability.
Urban heat can cause or exacerbate health impacts such as heat stress, resulting in illness or death, and can also
compound issues of social isolation by reducing comfort levels in outdoor areas and meeting places. It may also
result in increased living costs associated with air conditioning and transport. Resulting flow on effects can include
increased demand for medical care and emergency services, resulting in resource strains for local government,
hospitals and emergency services.
Thermal data has the potential to be used to identify whether urban heat risks are likely to disproportionally affect
vulnerable residents, and enable mitigation measures to be prioritised to these areas. Loughnan et al (2009)
developed a method to identify broad spatial patterns of vulnerability to heat stress at the local government area
level. This utilises a series of 5 indicators:
-
Large numbers of aged care facilities
-
Language other than English spoken at home
-
Elderly people living alone
-
Low density (suburban) areas
-
High proportion of very old or very young residents.
While broad scale analysis of this nature is useful in identifying general patterns of vulnerability, Norton et al
(2013) recognise the need for ‘finer grain’ analysis to enable specific, localised responses to be undertaken. A
recently launched online mapping project based on this report, ‘Mapping Vulnerability Index1’, undertakes this at
census collector district level for all Australian capital cities. This online resource, and the discussion found in the
VCCCAR supported report ‘Decision principles for the selection and placement of green infrastructure to mitigate
urban hotspots and heat waves’, could be utilised by CoGG and WCC to further explore the geographic spread of
vulnerability, intersection of this with urban heat ‘hot spots’ and prioritise mitigation efforts in these area.
The following sections introduce some of the broad indicators of vulnerability for CoGG and WCC. It was not
within the scope of this report to undertake detailed, localised analysis of the intersection between vulnerability
and urban heat impacts, however it is recommended that this is undertaken as CoGG and WCC plan and
prioritise specific urban heat responses.
3.4.1
City of Greater Geelong
The following indicators of vulnerability are taken from the CoGG Profile.id website (2013a).
Age
CoGG has an older population in comparison to Greater Melbourne. Residents in the older age range, such as 65
and over, are not distributed evenly throughout the municipality which may indicate areas with a higher proportion
of older residents are more vulnerable.
Disability
Approximately 5.6% of the CoGG population requires assistance with day-to-day tasks due to disability. This
population is not evenly distributed across the municipality, and a number of areas of high concentration of
disability assistance are evident.
Income and education
1
NCCARF, CRF for Water Sensitive Cities, Water for Liveability and Monash University (accessed 22.07.13),
http://www.mappingvulnerabilityindex.com/
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CoGG has a SEIFA score of 993, placing it around the middle of the ranking of disadvantage across Victoria’s
municipalities. Within the municipality, the SEIFA index notes the highest level of disadvantage in the following
suburbs:
-
Norlane
-
Whittington
-
Corio
-
Thomson/Breakwater.
Specific analysis of thermal data for these areas was not undertaken through this project, however all are located
within parts of the municipality that experience urban heat effects. Further detailed analysis to understand the
intersection between the most vulnerable parts of the community and the most severe urban heat impacts would
enable localised mitigation to be prioritised.
3.4.2
City of Wyndham
The following indicators of vulnerability are taken from the WCC Profile.id website (2013b).
Age
WCC has a younger population in comparison to Greater Melbourne, potentially reducing vulnerability to the
health impacts of urban heat. Residents in the older age range, such as 65 and over, are not distributed evenly
throughout the municipality which may indicate areas with a higher proportion of older residents are more
vulnerable.
Disability
Approximately 3.4% of the WCC population requires assistance with day-to-day tasks due to disability. This
population is not evenly distributed across the municipality, and a number of areas of high concentration of
disability assistance are evident.
Income and education
WCC has a SEIFA score of 1,013, placing it around the middle of the ranking of disadvantage across Victoria’s
municipalities. Within the municipality, the SEIFA index notes the highest level of disadvantage in the following
suburbs:
-
Heathdale
-
Manorvale
-
Woodville
-
Mossfiel.
Specific analysis of thermal data for these areas was not undertaken through this project, however all are located
within parts of the municipality that experience urban heat effects. Further detailed analysis to understand the
intersection between the most vulnerable parts of the community and the most severe urban heat impacts would
enable localised mitigation to be prioritised.
3.5
Potential impact from climate change
Climate change projections prepared by CSIRO and the Bureau of Meteorology (BoM) provide an indication of the
likely effect of future climate change on temperatures, rainfall, extreme weather events and sea level. These
projections are based on greenhouse gas emission models and scenarios used in the Intergovernmental Panel on
Climate Change (IPCC) Fourth Assessment Report (2007). While the extent of projected changes will vary
between specific locations within the CoGG and WCC local government areas, the broad changes expected are
largely consistent. The detail of localised impacts are highly uncertain and beyond the scope of this project to
explore, and are also less relevant when considering urban heat impacts at a strategic level.
The primary climate changes that will impact on urban heat are changes to temperatures, both average
temperatures and number of extreme heat events, and changes in rainfall patterns. Key projected changes that
could influence future urban heat are summarised below (DSE 2008a):
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City of Greater Geelong (Corangamite Region)
Temperature
-
Under a medium emissions scenario, annual average temperature is expected to be between 0.5 to 1.1ºC
warmer in 2030.
-
By 2070, average annual temperature are expected to be between 0.8 to 1.8ºC warmer under a lower
emissions scenario or between 1.6 to 3.5 ºC warmer under the high emissions scenario.
-
The number of days over 30ºC each year is expected to increase from 21 to 26 by 2030 and up to 40 by
2070.
-
The number of days over 35ºC each year is expected to increase from 4 to 6 by 2030 and up to 12 by 2070
under a high scenario.
Rainfall
-
While conditions are expected to be drier, when it does rain, rainfall intensity is expected to increase. Under
a high emissions scenario average annual rainfall could decrease by up to 12% by 2070.
3.5.2
Wyndham City Council (Port Phillip and Westernport Region)
Temperature
-
Under a medium emissions scenario, annual average air temperature is expected to be between 0.6 to
1.1ºC warmer in 2030.
-
By 2070, average annual air temperature are expected to be between 0.9 to 1.9ºC warmer under a lower
emissions scenario or between 1.8 to 3.7 ºC warmer under the high emissions scenario.
-
The number of days over 30ºC each year is expected to increase from 30 to 34 by 2030 and up to 49 by
2070.
-
The number of days over 35ºC each year is expected to increase from 9 to 11 by 2030 and up to 20 by 2070
under a high scenario.
-
The number of days over 40ºC each year could double by 2030 and increase to up to 5 days by 2070.
Rainfall
3.5.3
While conditions are expected to be drier, when it does rain, rainfall intensity is expected to increase. Under
a high emissions scenario average annual rainfall could decrease by up to 24% by 2070.
Potential impact of climate change on urban heat
Increases in temperature may increase the absorption and retention of heat by built surfaces. Changes to rainfall
patterns may reduce vegetation cover and reduce the moisture content of ground surfaces, which can result in
increased daytime surface heating. In a broad sense, it is likely that these projected changes will exacerbate the
extent and impacts of urban heat already being observed. Discussed in section 3.0 above, this could result in
impacts on health, infrastructure, essential service delivery and the economy.
Table 3 Projected changes in number of extreme heat days in Melbourne (DSE 2008b)
2030 (medium
emissions)
Current
2070 (low
emissions)
2070 (high
emissions)
Annual days over
30C
30
34
39
49
Annual days over
35C
9
11
14
20
Annual days over
40C
1
2
3
5
The table above summarises the potential increase in days of extreme heat for the Melbourne region, a
particularly relevant indicator when considering urban heat impacts. It highlights the significant changes projected
under current climate change scenarios. An increase in the frequency of extreme heat days is likely to result in an
increase in hospital admissions, injuries and deaths due to heat stress, dehydration and sunburn, as well as
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disruptions to transport and other essential infrastructure and services (DSE 2008b). If urban heat is not
managed, these impacts could be significantly exacerbated.
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4.0
Responding to UHI risks
4.1
Practical mitigation responses
27
A range of measures have been identified in the review of relevant literature that have potential to reduce urban
heat impacts. These are outlined in Table 4 below. The measures relevant to City of Greater Geelong and
Wyndham City Council will depend on the individual circumstances of the facility or urban area being considered,
as well as the objectives of the mitigation effort. All of these practical mitigation measures need to be considered
by councils in plan making and operations.
Table 4 General urban heat mitigation opportunities (adapted from Coutts et al 2010).
Mitigation measure
Desired effect
Increase vegetation
Encourage evapo-transpirative cooling, shade built surfaces.
Water sensitive urban design
Retain water to increase evaporation, increase water availability for
irrigation.
Increased albedo
Increase reflection of solar radiation, reducing heat storage.
High thermal emittance surfaces
(use of reflective coating for roof
surfaces, allowing traditional
colours to be maintained).
Reduce heat storage in roof coverings.
Outdoor landscaping
Protect buildings from solar radiation using external vegetation. Use of
deciduous species can allow protection in summer and access in winter.
Street design
Use street orientation and width to allow urban ventilation and balance
urban heat impacts with passive thermal performance.
Parkland and open space
Use vegetated open space to provide local cooling, including for
surrounding urban areas.
Green roofs / walls
Reduce heat transfer into buildings and encourage evapotranspiration.
Evaporative air coolers
Reduce the release of waste heat from reverse cycle air conditioning
outside buildings (increased water consumption is a drawback).
Building design
Improve occupant comfort and reduce cooling requirements.
Mass transport / active transport
Reduce private vehicle use, resulting in less waste heat from exhaust.
4.2
Plan making
The tables below highlight examples of council strategies and plans where there may be opportunities to make
specific mention of urban heat risks and mitigation approaches, or where there are opportunities to improve what
is already incorporated into existing plan documents. It should be noted that the examples included below
represent a small sample of the opportunities that may exist to better incorporate urban heat considerations into
Council plans and strategies, and a complete review of existing plans and strategies has not been completed as
part of this study.
4.2.1
City of Greater Geelong
Table 5 Key plans and strategies – City of Greater Geelong.
Plan
Current status and opportunity
Precinct Structure
Plans (PSP)
The Armstrong Creek East Precinct and Town Centre PSPs were reviewed to understand
current appreciation of urban heat in the context of future development. 26,207 of the
76,460 expected population growth to 2031 in CoGG is projected for the Armstrong
Creek Growth Area. Ensuring PSPs for this area adequately consider urban heat risks,
among other sustainability and liveability considerations, will make a significant impact.
The PSPs reviewed made no specific reference to urban heat, however a range of
provisions were identified that may support reduced urban heat impacts. These include
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Plan
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Current status and opportunity
objectives, guidelines and requirements related to:
-
shading streets and pedestrian spaces through verandahs and shade trees
-
minimising areas of unshaded car park
-
urban form and landscaping to provide shade around buildings.
Future PSPs represent an important opportunity to consider how street design and
orientation, water management and landscaping can support improved urban heat
outcomes. High level strategic objectives, supported by more detailed provisions in
design guidelines and infrastructure plans, could be altered to include consideration of
urban heat.
PSP Guidelines include a requirement for an energy statement. Urban heat is a
consideration that should form part of this statement, given its potential to increase
energy consumption
2009-2013 Geelong
Health and Wellbeing
Plan
The current Geelong Health and Wellbeing Plan expires this year. This represents an
important opportunity to bring the consideration of urban heat into the municipality’s
strategic plan for community health and wellbeing. The current plan recognises the
impact that urban design and open space networks can have on health and wellbeing,
however does not recognise the potential risks of urban heat in this context.
The revised plan could recognise the impact urban heat can have on physical and mental
health, and recommend consideration of urban heat impacts in the context of service
delivery, emergency management planning, new urban development and Council
facilities. In particular, the plan could identify risks to vulnerable segments of the
community, and put in place strategies to manage these risks.
City of Greater
Geelong Heatwave
Management Plan
The CoGG Heatwave Management Plan, developed in October 2009, sets out the
systems and processes Council intends to put in place to reduce the impact of heatwaves
on public health. The plan makes note of the factors contributing to health impacts of
heatwaves, however makes no specific mention of the potential for heatwaves impacts to
be exacerbated by urban heat. As has been outlined in this report, local temperatures
can be significantly influenced by the built form and landscaping associated with urban
environments. In the event of a heatwave, areas likely to experience higher temperatures
due to urban form could be more vulnerable to public health impacts.
A revised Heatwave Management Plan should recognise this elevated risk and include
procedures to respond. Subject to further work and analysis, a heatwave vulnerability
map could be developed that made note of both the most vulnerable populations as well
as the urban areas most likely to experience elevated temperatures.
4.2.2
City of Wyndham
Table 6 Key plans and strategies – City of Wyndham.
Plan
Current status and opportunity
Precinct Structure
Plans (PSP)
Existing PSPs for Ballan Road and Manor Lakes were reviewed, to understand current
recognition of urban heat impacts. While these plans make no specific reference to urban
heat, they do include a range of provisions that have potential to support improved urban
heat outcomes. These include objectives, guidelines and requirements related to:
-
encouraging canopy tree cover in streets, car parks and open spaces (e.g. Ballan
Road PSP and Manor Lakes PSP)
-
integration of open space networks (e.g. Ballan Road PSP)
-
using recycled water to contribute to maintaining a green urban environment (e.g.
Ballan Road PSP)
-
use of buildings and landscape treatments to provide shade (e.g. Manor Lakes).
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Current status and opportunity
Future PSPs represent an important opportunity to consider how street design and
orientation, water management, landscaping, and material and colour selection can
support improved urban heat outcomes. High level strategic objectives, supported by
more detailed provisions in design guidelines and infrastructure plans, could be altered to
include consideration of urban heat.
PSP Guidelines include a requirement for an energy statement. Urban heat is a
consideration that should form part of this statement, given its potential to increase
energy consumption
Municipal Strategic
Statement (MSS)
The MSS sets the broad strategic direction for planning across the municipality. It is
currently under review, with a draft version out for comment. Key urban heat concepts
and actions relevant to strategic and statutory planning could be included in the final draft
of the MSS, providing a strategic basis for future planning decisions that consider urban
heat impacts.
Community Health
and Wellbeing Plan
The Community Health and Wellbeing Plan is due to expire at the end of 2013. The
revised version of this plan has the opportunity to consideration to urban heat impacts on
health and wellbeing. Vulnerable populations, such as the elderly and disabled, can be
disproportionally affected by extreme heat, and urban heat impacts have the potential to
exacerbate this.
Recreational behaviours and exercise can also be impacted. As shown by analysis of
surface temperature of public open spaces including ovals and play grounds design,
material selection and landscaping can significantly influence surface temperatures of
important public spaces.
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Operations / implementation
In addition to being considered at a strategic level in plan making, councils also need to consider urban heat in
their day to day operations, including maintenance and replacement activities (buildings and public open space),
provision of guidance and statutory decision-making (planning) and in considering public health and emergency
response policies and procedures.
The following tables provide an indication of the potential relevance of urban heat to each council directorate for
both CoGG and WCC. This is not intended to be exhaustive, but to provide an initial indication of the potential
risks or responses that each directorate may consider in relation to urban heat.
4.3.1
City of Greater Geelong
Table 7 Integrating urban heat into core function activities – City of Greater Geelong
Directorate
Core functions
Urban heat relevance
City services
Engineering
Environment and Natural Resources
Infrastructure Operations and Waste
Parks and support services
Consideration of urban heat in specification
and design of new infrastructure, maintenance
of existing infrastructure.
Community services
Aged and Disability Services
Arts and Culture
Community Development
Family Services
Health and Local Laws
Planning for urban heat impacts on vulnerable
groups, including elderly and disabled
members of the community.
Potential to reduce passive street surveillance
during extreme events and subsequently
increase crime rates and anti-social behaviour.
Corporate services
Communication and Marketing
Administration and Governance
Corporate Strategy and Property
Management
Customer Services and Councillor
Support
Financial Services
Information Services
Organisation Development
Produce property management guidance
outlining urban heat responses
City Development
Planning Strategy and Economic
Development
Tourism
Consider incorporating assessment of urban
heat risks in new subdivisions and planning
permit approvals processes.
Economic development,
planning and tourism
Incorporate into future climate change
adaptation work, including Barwon South West
regional plan.
Integrating urban heat mitigation into
upcoming strategies, budgets, staffing,
resourcing, link to updated risk register.
Consider and plan for potential increased
cooling costs due to a combination of climate
change and rising energy prices, compounded
by urban heat.
Consider inclusion of specific reference to
urban heat in future revisions of the Municipal
Strategic Statement (MSS), new overlays and
zone amendments.
Encourage developers to include urban heat
mitigation provisions in urban design
guidelines of new estates (e.g. roof colour and
landscaping).
Produce planning and design guidance for
new development, renewal projects and
renovations. This to consider various scales
including precinct/subdivision, block, street
and individual building.
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Directorate
Core functions
Urban heat relevance
Projects, recreation and
central Geelong
Capital Projects
Events, Central Geelong and
Waterfront
Leisure Services
Sport and Recreation
Strategic Projects/Urban Design
Consideration of urban heat in specification
and design of new Council facilities including
buildings, open spaces and sporting facilities.
4.3.2
Consider urban heat outcomes in street tree
selection and maintenance, landscaping and
maintenance of parks (including irrigation).
City of Wyndham
Table 8 Integrating urban heat into core function activities – City of Wyndham
Directorate
Core functions
Urban heat relevance
Sustainable
Development
Communications and Events
Town Planning
Environment and Sustainability
Economic Development
Strategic Planning
Consider urban heat in development of future
environment and climate change strategies,
including adaptation planning.
Consider inclusion of specific reference to
urban heat in future revisions of the Municipal
Strategic Statement (MSS), new overlays and
zone amendments.
Encourage developers to include urban heat
mitigation provisions in urban design
guidelines of new estates (e.g. roof colour and
landscaping).
Consider incorporating assessment of urban
heat risks in new subdivisions and planning
permit approvals processes.
Produce planning and design guidance for
new development, urban renewal projects and
smaller buildings. This to consider various
scales including precinct/subdivision, city
block, street and individual building.
Community
Development
Libraries and Community Learning
Aged, Disability and Recovery
Early Years and Youth
Social Development
Business Services
Advocacy
Corporate Services
Planning for urban heat impacts on vulnerable
groups, including elderly and disabled
members of the community.
Advocate for urban heat impacts to be
incorporated into State Planning Policy
Framework, to provide strategic support for
local responses.
Information Services
City Governance
Financial Services
Risk and Compliance
Organisational Development
Increased urban heat impacts have the
potential to reduce passive street surveillance
during extreme events and subsequently
increase crime rates and anti-social behaviour.
Produce property management guidance
outlining urban heat responses
Integrating urban heat mitigation into
upcoming strategies, budgets, staffing,
resourcing, link to updated risk register.
Infrastructure
City Presentation and Recreation
Buildings and Waste
Major Projects
Consideration of urban heat in specification
and design of new Council facilities including
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Core functions
Urban heat relevance
Engineering Services
Parks
Assets Management and
Maintenance
buildings, open spaces and sporting facilities.
Consider urban heat outcomes in street tree
selection and maintenance, landscaping and
maintenance of parks (including irrigation).
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5.0
Limitations and next steps
5.1.1
Limitations
33
High resolution thermal mapping provides a great communication tool to convey the idea of urban heat. However,
there are some limitations with high resolution thermal imagery that are of concern.
Corrections: Thermal remote sensing actually involves the measurement of surface radiation, and using the
inverse of Plank’s Law, is converted to a surface ‘brightness’ temperature. Data supplied by the provider here is
essentially a raw data product that has only been radiometrically corrected. The data is not corrected for:

Atmospheric effects: As radiation from the land surface passes through the atmosphere to the sensor, it is
affected by absorption by the atmosphere. This is related to the transmittance and emittance of the
atmosphere and varies with temperature and humidity. Given the low altitude, and the warm, dry conditions at
the time of the flight, these effects are likely to be relatively small (Figure 7).

Emissivity: Surface temperatures are influenced by the emissivity (the ability of a surface to emit radiation).
Surfaces with a low emissivity appear cool when they may in fact be warm. This is especially evident for
rooftops (e.g. corrugated iron) where emissivity is very low. Current procedures for dealing with emissivity
correction for high resolution thermal imagery are inadequate, though is probably the largest source of error.

Directional effects: The sensor actually ‘sees’ surface radiation from multiple directions and those
temperatures from surfaces that are ‘off-nadir’ may appear cooler than those surfaces located directly
perpendicular to the surface (e.g. viewing a thermal image of a wall, the apparent temperature of the wall
may change at the edges of the image, when in fact the temperature is the same). Topographic changes can
also be corrected for.
The implication of this is that the actual surface temperature values observed by the sensor are not precise and
can be several degrees out. Addressing these corrections increases the cost associated with capture and postprocessing. The thermal maps provide an idea of the relative differences in surface temperature rather than
absolute temperature differences.
Figure 7: Demonstration of the effects of different corrections applied (e.g. atmospheric and direction corrections listed above) for a
transect across the city of Vancouver BC. Directional brightness is equivalent to the data provided to Geelong and Wyndham. These
data are a coarser resolution, but demonstrate the uncertainty of not undertaking corrections (Voogt and Oke, 2003)
Plan view only: The image only provides a bird’s-eye-view of the surface, and so does not capture the full 3D
nature of the urban environment which influences urban micro-climates.
Snapshot in time: Land surface temperatures at this high resolution are clearly highly variable spatially, but also
temporally. Surface temperatures will change with different times of capture, different meteorological conditions,
and changing surface conditions (e.g. soil moisture). This makes meaningful comparisons of images over time
difficult. It is not really possible to establish a ‘baseline’ dataset of surface temperature.
Surface-air temperature relationships: The key assumption in using thermal data for urban climate analysis is
that air temperature patterns follow land surface temperature patterns. However, Tomlinson et al. (2011) states
that “a significant research gap still exists which is the quantification of the relationship between measured air
temperatures and remotely sensed LST data”. This is especially true at the micro-scale for high resolution thermal
data. Wind speed and atmospheric stability influence correlations and they are poorer during the day when the
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atmosphere is unstable and turbulence is higher. As an example, surface temperatures may be high next to the
ocean, but air temperatures would be low due to sea breezes.
Building energy efficiency: This thermal data cannot be used to identify poor performing buildings in terms of
energy efficiency. The uncertainty with emissivity means that rooftop temperatures are not precise. Also, surface
temperatures are just that: they do not give an indication of the insulating effects of buildings or their energy
efficiency.
Data quality: Quality data collection is essential. The data quality of these images appears very good. Flight need
to be conducted progressively over the target area (e.g. East to West). Obviously, an issue for Geelong is the time
taken for flights meant that the surface heated as the collection of data was undertaken. Taking N-S strips of data
will make presentation and interpretation of data easier. This has been an issue in other thermal mapping
exercises. A balance between resolution and flight time is needed. If smaller focus areas are identified for thermal
mapping, this reduces the time – flights should probably aim to be less than one hour in duration.
5.1.2
Further work
Thermal imagery: Identifying hot-spots in the landscape is good way to help prioritise investment in reducing
urban temperatures. In deciding on future thermal mapping exercises, it is critical that the objectives of mapping
are clear. If information is sought on a particular focus area for intervention (e.g. retro-fit), then high resolution
thermal imagery may be useful for this purpose to identify hot streets, or to target unirrigated areas, etc. but, the
limitations should be kept in mind. However, the imagery already collected provides information on the types of
surfaces and urban arrangements/designs that cause high surface temperatures, which is not likely to change. In
developing new areas and retrofitting existing areas, targeting areas with high solar access will help improve
human thermal comfort. In summary, the benefits of high resolution thermal mapping are dependent on the
objective of the mapping exercise. If mapping is to be undertaken again it should focus on target areas, consist of
short duration flights, and should be corrected as best as possible.
Mapping vulnerability: As noted earlier in the report, a heatwave vulnerability map could be developed that
made note of both the most vulnerable populations as well as the urban areas most likely to experience elevated
temperatures
Satellite imagery: An alternative approach is the use of satellite imagery. A variety of products are available at
different resolutions. LANDSAT has been used many times in studies of urban heat island. LANDSAT ETM+ data
is available from 1999 onwards, and can provide 30m resolution. There are limitations with LANDSAT data (i.e.
captured every 16 days, capture at 11am only, data from 2003 only 80% of scene available). An example of
LANDSAT ETM+ data is provided in Figure 8 below. While limitations exist, benefits include standardised
approaches for all the necessary corrections including atmospheric and emissivity corrections. The entire region is
captured simultaneously, eliminating effects of flight time that were seen for Geelong. A new LANDSAT satellite
has been launched and will become operational in 2013. This coarser data can still be used to identify hots-spots
in combination with aerial photography, and may be easier to identify though this approach. The coarser scale
probably means a better representation of air temperature variations too.
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Figure 8: Comparison of high resolution (0.5m) thermal mapping (left) versus 30m resolution of the same data (middle). LANDSAT
satellite data provides a similar image to the scaled up version here. The LANDSAT image (right) is for 11am 25 Feb 2012. The ‘hotspots
are in the same location as the high resolution thermal image, as are the cool spots. The white bands are the missing data.
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References
Coutts, Andrew, Beringer, Jason and Tapper, Nigel(2010) 'Changing Urban Climate and CO2 Emissions:
Implications for the Development of Policies for Sustainable Cities', Urban Policy and Research,, First published
on: 06 January 2010 (iFirst)
Department of Sustainability and Environment (2008a), Climate Change in Victoria, Victorian Government,
Melbourne.
Department of Sustainability and Environment (2008b), Climate Change in Port Phillip and Western Port, Victorian
Government, Melbourne.
Forecast.id (2013a), Wyndham City Council Population Forecasts,
http://forecast2.id.com.au/Default.aspx?id=124&pg=5330, viewed 06/06/13.
Forecast.id (2013b), City of Greater Geelong Population Forecasts,
http://forecast2.id.com.au/Default.aspx?id=268&pg=5320, viewed 06/06/13.
Loughnan, Margaret, Nicholls, Neville, & Tapper, Nigel. (2009). Hot spots project: A spatial vulnerability analysis
of urban populations to extreme heat events. Retrieved 1 February 2013, from
http://docs.health.vic.gov.au/docs/doc/2BE6722DD7C4874ACA257A360024E0DE/$FILE/heatwaves_hotspots_pr
oject.pdf
Loughnan, ME, Tapper, NJ, Phan, T, Lynch, K, McInnes, JA (2013), A spatial vulnerability analysis of urban
populations during extreme heat events in Australian capital cities, National Climate Change Adaptation Research
Facility, Gold Coast pp.128.
Norton, BA, Coutts, AM, Livelsley, SJ, Williams, NSG (2013) Decision principles for the selection and placement
of green infrastructure to mitigate urban hotspots and heat waves. VCCCAR report. University of Melbourne and
Monash University.
http://www.vcccar.org.au/sites/default/files/publications/Urban%20Heat%20Island%20Decision%20principles%20
green%20infrastructure.pdf
Nury, S, Coutts, A and Beringer, J (2012), The spatial relationships between vegetation, built area and land
surface temperature distribution in the City West Water service area using satellite imagery, City West Water and
Monash University, Melbourne Australia.
Profile.id (2013a), City of Greater Geelong, http://profile.id.com.au/geelong, viewed 06/06/13.
Profile.id (2013b), Wyndham City Council, http://profile.id.com.au/wyndham, viewed 06/06/13.
Tomlinson, C. J., Chapman, L., Thornes, J. E. & Baker, C. 2011. Remote sensing land surface temperature for
meteorology and climatology: a review. Meteorological Applications, 18, 296-306.
Voogt, J. A. & Oke, T. R. 2003. Thermal remote sensing of urban climates. Remote Sensing of Environment, 86,
370-384.
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Appendix A
AECOM has not been commissioned to undertake a comprehensive literature review on urban heat. The
documents that have been reviewed to preparing this executive report are outlined in Table 2.
Table 9: Literature reviewed
Title
UHI focus and practical use
Decision principles
for the selection and
placement of green
infrastructure to
mitigate urban
hotspots and heat
waves
Urban heat mitigation
opportunities (including impact
of green infrastructure)
Reducing Urban
Heat Islands:
Compendium of
Strategies
Heat Island
Reduction Activities
Provides a summary of the
strategies, as distinct from
individual measures, that can
be used to reduce urban heat
island. Largely aimed at
government organisations, it
summarises approaches such
as demonstration projects,
incentive programs, planning
and building policies etc.
Document
type/citation
Author
Date
Research paper
Briony A. Norton,
Andrew M. Coutts,
Stephen J.
Livesley and
Nicholas S.G.
Williams
March
2013
Government report
Climate Protection
Partnership
Division in the
U.S.
Environmental
Protection
Agency’s Office of
Atmospheric
Programs
ND
See citation
2010
AECOM, for City
of Melbourne
14
November
2012
Provides useful and pragmatic
advice regarding the potential
impact of different types of
green infrastructure on urban
heat, and the relevant
considerations when planning
for use of green infrastructure.
The strategies contained in this,
while discussed in a USA
context, have potential for
transfer to the CoGG and WCC
contexts.
Changing Urban
Climate and CO2
Emissions:
Implications for the
Development of
Policies for
Sustainable
Cities
Provides a discussion of the
importance of considering
urban climates when planning
for future, sustainable urban
development. Particular focus is
given to the potential duel
benefits associated with some
UHI mitigation measures, which
are found to also have potential
benefits in efforts to reduce
greenhouse gas emissions and
improve the sustainability of
water management.
Journal article
Economic
Assessment of
the Urban Heat
Island Effect
This report analyses the
economic impact of current and
future UHI effects on the City of
Melbourne. It explores the
Consultant report
Coutts, Andrew,
Beringer, Jason and
Tapper, Nigel(2010)
'Changing Urban
Climate and CO2
Emissions:
Implications for the
Development of
Policies for
Sustainable Cities',
Urban Policy and
Research,, First
published on: 06
January 2010
(iFirst)
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Title
City of Greater Geelong and Wyndham City Council
Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
UHI focus and practical use
38
Document
type/citation
Author
Date
See citation
2008
Sultana Nasrin
Nury
Dr. Andrew Coutts
Prof. Jason
Beringer
June 2012
impact of UHI on extreme heat,
and the impact of extreme heat
on health, transport, energy
demand, trees and animals and
crime, and the costs associated
with this.
It provides a useful discussion
of the economic costs that may
be attributable to UHI for
Melbourne’s CBD. It notes that
mitigation efforts would be
improved if a cost benefit
analysis was undertaken for the
range of available measures to
reduce UHI.
Urban form and
climate change:
Balancing
adaptation and
mitigation
in the U.S. and
Australia
This article does not directly
focus on UHI, but considers it in
the context of future climates
and the need for cities to
effectively prepare for changed
climates. It uses case studies to
discuss the relationship
between measures to mitigate
climate change and measure to
adapt to climate change. It finds
that in some cases these
measures are complementary,
while in others they are
potential conflicts.
The summary of practical
actions being taken at a local
scale (largely in the US and
Australia) provides a useful
reference point for local
governments.
Journal article
The spatial
relationships
between vegetation,
built area and land
surface temperature
distribution in the
City West Water
service area using
satellite imagery
This technical paper focuses on
the relationships between
vegetation, built form and
surface temperature.
Research report
Hamin E.M., &
Gurran, N.,, Urban
form and climate
change: Balancing
adaptation and
mitigation in the
U.S. and
Australia, Habitat
International (2008),
doi:10.1016/j.habitat
int.2008.10.005
It finds that, within the area
studied which includes
Wyndham, there is a strong
relationship between both
vegetation cover and built form,
and surface temperature.
Effectively, the more built up
areas with lower vegetation
cover generally showed higher
surface temperatures. It
concludes that increasing
vegetation cover can be an
appropriate measure to reduce
surface temperatures, and that
thermal mapping can be useful
in identifying specific locations
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UHI focus and practical use
Document
type/citation
Author
Date
Charlie J.
Tomlinson, Lee
Chapman, John
E. Thornes and
Christopher Baker
2011
for targeted intervention.
Remote sensing
land surface
temperature for
meteorology
and climatology: a
review
This technical paper reviews a
range of remotely sensed data
sources in the context of land
surface temperature. It focuses
on thermal infrared sensing, for
use in applications such as
urban heat island
measurements.
It is a relatively technical paper,
with potential value in decision
making regarding the most
appropriate data sources for
future UHI measurement and
monitoring.
Journal article
Adapting to
Urban Heat:
A Tool Kit for
Local Governments
This tool kit was prepared to
guide American local
governments in decision
making regarding UHI
mitigation. It presents a
decision making framework to
consider a series of outcome
criteria and governance criteria
for four UHI mitigation
measures (cool roofs, green
roofs, cool pavements, urban
forestry).
It provides a useful discussion
of relevant decision making
considerations for local
governments, and while
directed to an American
context, has potential
applicability for Australian local
governments.
Local Government
tool kit
Georgtown
Climate Centre
Sara P. Hoverter
August
2012
Climate Change
Adaptation in Urban
Systems: Strategies
for Planning
Regimes
This research focuses on the
opportunities and tools
available to planners to improve
the ability of urban systems to
respond to climate change
through effective adaptation.
While not specifically focused
on UHI, some specific
interventions discussed have
UHI mitigation potential, and the
use of planning policies and
strategies more broadly is
highly relevant when exploring
opportunities for local
governments to address UHI.
Research paper
Tony Matthews
February
2011
Responding to the
Urban
Heat Island: A
Review of the
Potential of Green
A review of international
research in to the potential of
green infrastructure to mitigate
urban heat island impacts. It
looks specifically at shade
Literature review
Annie Hunter
Block, Stephen J.
Livesley,
Nicholas S.G.
Williams
2012
Meteorological
Applications
Meteorol. Appl. 18:
296–306 (2011)
Urban Research
Program
Research Paper 32
February 2011
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Title
UHI focus and practical use
Infrastructure
trees, green roofs and green
walls and facades. It concludes
that these green infrastructure
elements can have a positive
impact on local surface and
ambient temperatures, however
their impact on the broader
urban heat island at a city scale
is less clear.
It provides a useful summary of
the characteristics and benefits
of these three types of green
infrastructure and discussion of
their potential use in Australian
climates.
Document
type/citation
Author
40
Date
VCCAR
A multi-scale
assessment of
urban
heating in
Melbourne during
an extreme
heat event and
policy approaches
for
adaptation
This technical study focuses on
examining airborne thermal
imagery to explore the impact of
surface types and urban
arrangements on surface
temperatures.
Research report
Andrew Coutts &
Richard Harris
School of
Geography and
Environmental
Science
Monash University
November
2012
A spatial
vulnerability
analysis of urban
populations during
extreme heat events
in Australian capital
cities
Final Report
This paper presents the results
and recommendations of the
development and analysis of a
tool exploring health
vulnerability and urban heat. It
found that key vulnerability
indicators for heat-related
health impacts in urban areas
included demographic features
such as older populations,
disabled residents, ethnicity and
cultural diversity.
It concluded that a range of
mitigation opportunities were
available, and that due in part of
projected future climate change,
without mitigation heat related
illness and death are likely to
rise.
Research paper
Dr Margaret E
Loughnan
Professor Nigel J
Tapper
Dr Thu Phan
Kellie Lynch
Judith A McInnes
2013
Loughnan, ME,
Tapper, NJ, Phan,
T, Lynch, K,
McInnes, JA 2013,
A spatial
vulnerability
analysis of urban
populations during
extreme heat
events in Australian
capital cities,
National Climate
Change Adaptation
Research Facility,
Gold Coast
pp.128.
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Appendix B
Figure 9 CoGG thermal data
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Figure 10 WCC thermal data
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