Are Big Cities Ready to Mitigate Climate Change? Evidence from Sydney, Australia

Abstract

Governments across the world are facing challenges in urgently responding to the adverse impacts of climate change. Australian cities have been proactively working on various climate action plans. Despite this, the Climate Action Tracker rates Australia’s climate net zero targets, policies, and climate finance as “Insufficient”, highlighting the urgent need for substantial improvements to align Australia’s climate policies and commitments towards the Paris Agreement. This study explores the readiness of Australian cities towards climate change mitigation, with a focus on Sydney. It identifies prioritized cooling measures and proactive local governments in Great Metropolitan Sydney, through an analysis of official documents and policy statements. Interviews were conducted with local governments to gain insights into implementation processes, perceived effectiveness, challenges, and opportunities related to heat mitigation initiatives. The results reveal efforts to amend local environmental and development control plans to mitigate the urban heat island effect and create cooler, more comfortable built environments. However, challenges exist, including limited authority of local governments in urban planning, as national and state governments set stringent codes and regulations for heat mitigation. Financial constraints pose challenges, particularly in maintaining and monitoring strategic plans during their implementation stage, leading to the potential removal of sustainability measures from designs.

1. Introduction

Global climate change poses a critical threat to urban environments, manifesting in rising temperatures that significantly impact residents’ well-being [1] and exacerbate existing environmental challenges [2]. Urban areas are experiencing increased heat stress and thermal discomfort due to heatwaves and drought, threatening their livability and resilience [3,4]. Moreover, the vicious cycle of urban overheating not only leads to higher cooling-energy consumption in buildings and increases peak electricity demand [5], but also has severe implications for human health. Prolonged exposure to excessive heat can decrease human productivity [6], contribute to heat-related mortality, morbidity, and mental health problems [7], and cause serious health issues such as ischemia, hypoxia, and heat cytotoxicity, which damage cells and organs [8]. Urban overheating in Australia results from a combination of urban heat island (UHI) effects and dual atmospheric circulation systems, namely, cool sea breezes and hot winds from deserts [9]. To counterbalance the impact of urban overheating in cities, heat mitigation strategies and technologies have been developed and implemented. In this study, the term “mitigation” refers to “strategies and actions aimed at reducing the causes and severity of climate change impacts, particularly within urban environments” [10,11,12]. To date, numerous studies have thoroughly quantified the cooling potential of various heat mitigation strategies and their impacts in Australia [13,14,15,16], while others have assessed the impacts of urban planning and building typologies in UHI mitigation [17]. Heat mitigation strategies can significantly lower peak ambient temperatures [18], providing energy savings [19] and improved air quality [20]. For instance, blue infrastructure cools the environment through evapotranspiration, shading, the albedo effect, and groundwater recharge, creating micro-climates with lower temperatures [21]. Similarly, green infrastructure elements, such as green roofs, green walls, roof gardens, and nature-based solutions (urban trees, ground-level vegetation), provide insulation, decrease heat absorption by buildings, and promote evaporative cooling [22]. Trees and plants reduce heat by providing shade and lowering surface temperatures, while evapotranspiration further cools the air. Parks act as natural air conditioners by creating park breezes that draw air from cooler green areas toward warmer urban areas. Vegetation also dissipates heat by acting as a windbreak, modifying airflow, and facilitating natural ventilation [21].

In addition, the crucial role of green infrastructure in reducing mortality and morbidity rates, particularly through its positive impacts on cardiovascular health, has been well-documented in studies by Feng, X. et al. [23,24] in Australia. Their research demonstrated that increased tree canopy cover is significantly associated with lower cardiovascular disease (CVD)-related hospital costs. A 10% increase in the tree canopy near homes can reduce per person hospital costs for CVD by 4%. Increasing tree canopy cover to 30% for those with less than 10% could lead to significant health sector cost reductions, potentially saving billions of dollars if implemented nationwide [24].

In summary, scientific studies have demonstrated the effectiveness of various heat mitigation strategies, emphasizing their long-term mitigation measures, emergency plans, outreach activities, and resilient building practices [9]. However, the role of governments and local authorities in developing and implementing intervention strategies for climate mitigation and enhancing urban resilience is still a significant area of concern. Nevertheless, the Climate Action Tracker, 2024 [25] has acknowledged that governments globally struggle to meet the ambitious targets necessary to effectively combat climate change. Despite numerous international agreements and commitments, actual progress often falls short of what is needed to significantly mitigate climate change impacts. Australia’s climate targets, policies, and climate finance have been ranked as “Insufficient”, highlighting the urgent need for substantial improvements to align Australia’s climate policies and commitments with the Paris Agreement’s 1.5 °C temperature limit [25].

Existing research often overlooks the specific effectiveness, challenges, and opportunities of local government-led initiatives, highlighting the need for a detailed analysis to enhance understanding of local governance dynamics in climate action [26,27]. To close this gap, this study conducts a desktop review to investigate intervention strategies proposed and implemented by local government for urban cooling as part of climate change mitigation efforts, particularly in Sydney. Chosen for its status as Australia’s largest city by population, Sydney serves as a critical focal point in this research. With its dense urban fabric, extensive coastal areas, and diverse socio-economic landscape, Sydney exemplifies the intricate challenges posed by climate change in an urban context. The city’s size and prominence not only magnify the potential impacts of climate change, but also underscore the urgency of effective mitigation and adaptation strategies.

By concentrating on Sydney, this study serves as an initial attempt to evaluate the readiness of Australian cities to mitigate climate change risks. The desktop review involves examining official documents and policy statements. After the desktop review, a qualitative approach was used to conduct interviews with representatives from local governments—in other words, councils—known for their proactive stance on climate change mitigation. These interviews aim to understand implementation processes in climate mitigation initiatives and the challenges and barriers related to these processes. The research questions (RQs) this study addresses are as follows:

• RQ1: Which urban cooling measures are prioritized by governmental bodies in their policies and initiatives to mitigate climate change within the Greater Metropolitan Sydney area?
• RQ2: What are the key challenges and barriers faced by local governments in implementing urban cooling strategies, and how do these challenges and barriers affect the implementation process?

2. Materials and Methods

This research’s methodology comprises two distinct phases that collectively contribute to a full understanding of governmental interventions for climate change mitigation and urban cooling strategies.

2.1. In-Depth Analysis of Local Government Policies (RQ1)

On a wider scale, urban resilience strategies are being developed and implemented through comprehensive and collaborative programs like Resilient Sydney [28] and Turn Down the Heat [29]. These aim to minimize the effects of climate change while also improving heat resilience across various metropolitan settings. Resilient Sydney [28] includes all 33 councils in the Sydney metropolitan region and emphasizes integrated, cross-sectoral solutions to resilience. It focuses on raising awareness, building local capacity, and implementing initiatives like the Cool Suburbs program, and a flexible and resilient water cycle. The Turn Down the Heat [29] strategy, led by Western Sydney Regional Organization of Councils (WSROC), addresses the significant impacts of heat in Greater Sydney, especially Western Sydney, through collective efforts and innovative infrastructure projects.

Despite these broader initiatives, it is crucial to examine the performance of individual councils to understand the effectiveness of their specific measures and strategies. While collaborative programs provide a framework for action, the success of climate resilience largely depends on how well each council implements these initiatives at the local level. Councils experience climate change and its resulting urban overheating in diverse ways. The penalties for urban overheating are felt disproportionately. Vulnerabilities to urban overheating and UHI effects are unevenly distributed throughout the Sydney metropolitan area. For example, Western Sydney, home to more than 2.5 million people, is typically 6–10 °C hotter than the rest of the city during extreme heat events. This temperature difference is compounded by frequent hot westerly winds and limited cooling from sea breezes [30]. Residents in Western Sydney consume double the energy for cooling compared to those in the eastern suburbs, highlighting substantial disparities in heat exposure and energy use within the metropolitan area [31]. Social housing tenants in Western Sydney, face higher heat health risks compared to those in coastal urban areas, particularly financially disadvantaged individuals, those with chronic cardiovascular and respiratory illness, pregnant women, the elderly, and children [32].

The socio-economic status (SES) of councils within Greater Metropolitan Sydney varies significantly, as reflected in the 2021 Socio-Economic Indexes for Areas (SEIFA) by the Australian Bureau of Statistics [33]. The SEIFA index categorizes councils into five groups, ranging from the most disadvantaged (label 1) to the most advantaged (label 5). Councils in the inner city and northern suburbs generally fall within the higher SES categories (labels 4 and 5), indicating greater socio-economic advantages (Figure 1). In contrast, councils in the western and southwestern suburbs are more likely to be classified in the lower SES categories (labels 1 and 2), highlighting areas of socio-economic disadvantage. These lower-income populations, often residing in poorer-quality housing, may have reduced access to water, green spaces, information, and air-conditioning. Furthermore, the dual impacts of UHI and urban overheating disproportionately affect residents in western suburbs compared to those in the coastal eastern suburbs.

Thus, it is imperative to determine whether the more vulnerable councils adopt more proactive approaches or innovative solutions. Individual assessments allow us to identify best practices, pinpoint challenges unique to specific areas, and tailor recommendations that address the distinct needs and capacities of each council.

In this regard, to examine the diverse approaches to mitigating climate change, a desktop review was conducted for 30 councils (Figure 1). Greater Sydney is divided into 5 major districts, namely, Western City, Central City, Eastern City, North District, and South District. These districts together comprise 33 councils [34]. This study included cooling strategies for all councils, except Blue Mountains, Hawkesbury, and Wollondilly which falls in Western City district, and it follows the common policies developed by WSROC.

The methodology involved a desktop review process to analyze urban heat mitigation strategies across councils in Greater Metropolitan Sydney. First, all councils within the region were identified. Through in-depth analysis, a detailed record of the diverse approaches taken by these councils, including official documents, policy statements, and reports from each council, were reviewed to identify specific measures for urban heat mitigation. These measures were typically found in local strategy plans or separate documents, such as “Urban Forest Strategy”, “Responding to Climate Change Strategy”, and others, focused on sustainability and resilience. The implementation of these strategies was further assessed through yearly “Action Plan” documents published by the councils. Additionally, common measures and collaborative initiatives, such as “Resilient Sydney” [28] and “Turn Down the Heat” [29], were identified to understand regional efforts and shared approaches among councils. Data for this phase were sourced from the official websites of the councils.

2.2. Interviews with Local Governments (RQ2)

The second phase of this research comprised interviews with representatives from councils within the Greater Metropolitan Sydney area. Utilizing the desktop review of local government policies, eight councils were identified to participate in this study due to their proactive stance on climate change mitigation. The interviews, conducted with open-ended questions (see Appendix A), lasted approximately half an hour each. They were held online, and participants were approached via email to participate. Five councils participated in these interviews. The councils were consulted regarding the disclosure of their names. With the exception of two, the councils opted not to have their names revealed. By highlighting both their achievements and the obstacles they face, comprehensive insights and identification of areas for further development across local government initiatives were provided.

3. Results

3.1. Overview of Current Mitigation Measures and Their Implementation in Sydney Metropolitan Local Government Areas

The desktop review revealed the adoption of four overarching categories of strategies, each supported by specific toolkits and development-control regulations. These categories collectively underscore the councils’ comprehensive approach to urban sustainability (Figure 2), as follows:

• Urban greening and tree canopy. Initiatives aimed at augmenting green infrastructure and enhancing tree canopy cover within urban landscapes.
• Building design and materials. The utilization of urban design strategies and materials conducive to reducing heat absorption and mitigating UHI effects to inform urban planning decisions.
• Community engagement and education. Efforts directed towards raising awareness, fostering community engagement, and educating residents about the impacts of urban heat and the importance of mitigation measures.
• Water-sensitive urban design (WSUD). The adoption of design principles and practices that integrate water management into urban planning to mitigate heat and enhance sustainability.

Based on the annual reports and strategy plans of 30 councils, it was observed that the “Urban Greening and Tree Canopy” strategy is the most prevalent, featuring in 97% of the policies, indicating a strong emphasis on enhancing urban greenery. The “Building Design, Materials and Regulation” strategy follows with 67%, demonstrating a significant focus on sustainable construction practices. The “Community Engagement and Education” strategy is present in 50% of the policies, and, lastly, the WSUD strategy appears in 33% of the policies (Figure 2).

3.1.1. Urban Greening and Tree Canopy Enhancement

Initiatives in urban greenery have been a focal point in the climate change mitigation efforts of councils across various regions. These initiatives can be grouped into the following three key categories:

• Tree planting programs;
• Data-driven approaches;
• Strategic planning and policy advocacy.

Many councils have initiated extensive tree planting programs aimed at achieving specific canopy cover targets (see Appendix B;

Table A1. The review of council’s reports on urban heat mitigation.

Council	Mitigation Strategy	Implementation Plan/Progress Report
Bayside Climate Change [54]	Increasing tree canopy
	Including water features in the urban landscape through water sensitive urban design
	Installing pale paving and roads
Blacktown Responding to climate change strategy [62,70]	Use of permeable surfaces, cool materials, and vegetation	Increased tree canopy, biodiversity corridors, and tree plantings; Opening cool centers with community engagement activities
	Develop integrated water management strategy	Monitored water use during extreme heat days; Collaborated for heat sensors; Proposed guidelines for minimizing water consumption
Burwood Local Strategic Planning Statement [46,47]	Prepare street tree masterplan Evaluate controls for increased canopy coverage	500+ trees planted
	Provide natural and built shade	Shaded umbrellas installed
	Prioritize tree canopy in vulnerable locations;	Council secured $20.3M funding for arts center and park
Camden Sustainability Strategy 2020–24 [44,100]	Provide accessible water play parks	Two parks established at Curry Reserve
	Standardize engineering specifications; Implement green roofs, walls, and water-sensitive urban design	Planted 1800 trees to increase canopy by 25% by 2024; Developed WSUD operational guidelines
Campbelltown Toward a thriving city—our resilience hazard assessment [37,101]	Develop Urban greening Plan; Apply Bitumen based seal coat	Plant 11,580 trees; Educational programs on key species; Heat Mapping completed
	Establish two water play parks; Treat 7 play spaces for Urban Cooling	Guide “Changing Climate—A local council resource”; Shaded structures in parks
City of Canada Bay The council presently uses—Resilient Sydney Strategy 2018 [38]	City greening to promote healthy lifestyles and enhance comfort	Distributed 500 seedlings to local residents Planted 1800 trees; Gave away 1500 plants
	Changes to building codes and regulations	Development of street tree masterplan
	Engage in building resilience in local area	Conducted workshop on tree pruning; Provided educational information on website
City of Canterbury Bankstown Supporting Plan Resilient CBCity Strategic Plan [35,57]	Provide 10,000+ native plants annually; Plant 1000 trees on National Tree Day	NSW govt. sanctioned $900,000 for tree plantation; $160,000 used in 2022–23; 9700+ saplings given away
	Set net zero emissions by 2050; Increase tree canopy cover by 2036; Decrease waste to landfill by 40% by 2036	GreenAcre splash park developed for community access
	Developing Floodplain Risk Management, Urban Forest, Net Zero, and Climate Change Risk Assessment strategies	-
	Planning Controls	-
	Catchment Assessment	-
	Green Corridor Planning	-
	Renewable Energy Transition	-
Cumberland Heat smart toolkit [56,58]	Planting more trees for shade and increasing greenspaces	Implemented urban tree strategy
	Having a heatwave plan—organization, household or individuals Urban Cooling Measures	Designated library, swimming centers, community centers, and splash parks as heat refuges Marked water filling station Initiated Seniors & Disability Services Covered car park with trellis system Installed UV smart cool playground, thermal resistance shade, improved tree canopy
	Community Awareness	Used signboards for community awareness
Fairfeld City Natural Resources Programs in Fairfield City Council [39,102]	Plant additional trees in low canopy, high heat areas	Planted 12,020 native species
Hornsby Shire Environmental Sustainability Strategy—Sustainable Hornsby 2040 [103]	Planting Trees	-
	Building Envelope Augmentation	-
Hunter’s hill Local strategic planning statement [104]	Preserve existing trees as it reduce the effect of summer heat	-
Innerwest Local strategic planning statement [41,105]	Mitigate Urban Heat Island Effect	Preparation of urban forest policy/strategy; Tree maintenance; Built small park along Parramatta road corridor; Upgraded car park with tree/garden planting
Ku-ring-gai Climate Change Adaptation Strategy 2016 [106]	Work Hour Standards	-
	Insulate Buildings	-
	Cooling Systems	-
	Home Cooling Techniques	-
	Community Education	-
Lane Cove Climate Resilience Plan 2021–2026 [107]	Resilience for building, people urban open space, natural environment, and governance	-
Liverpool Liverpool Climate Action Plan [36,108]	Implement cooling designs in planning control	Phase 2 of Urban Forest strategy started with 3700 trees planted; New assets and devices developed as part of WSUD
Mosman Climate Action Plan—Mitigation Strategy [109]	Native Tree Corridor	-
	Heat Island Planting	-
North Sydney North Sydney Local Strategic Planning Statement 2020 [110]	Increase vegetation and tree canopy cover; Reduce energy use; Increase active/public transport; Retain water in landscape; Install vegetated stormwater systems; Use cool roof materials
Northern Beach Towards 2040 Local Strategic Planning Statement [111]	Greener Urban Environments Roof colors, cool pavements, wind circulation, green roofs, green walls, water-sensitive urban design, well-designed built and natural shade addressing UV radiation
	Investigate natural hazards and resilience framework; Implement Environment and Climate Change Strategy; Develop action plans for adaptation and resilience.
Parramatta WSROC toolkit [29,55]	Heat Refuge Places	Designated library, aquatic center, lakes, shopping center, and water play parks as cool refuges during heat
	Tree Plantation	Awarded $500,000 by NSW govt.; Planted 2600 trees
	Cool Road Trail	Conducted cool road trail with CoolSeal coats to reflect sun rays and minimize heat from asphalt
	Urban Greens	Provided more shades through urban greens
	Heat Mapping	Prepared city heat maps
	Research Collaboration	Collaborated with UNSW and Western Sydney University for microclimate and urban heat research
Penrith Penrith City Council Cooling the City: Planning for Heat Issues Paper The city also uses WSROC toolkit for Heat mitigation [43,60]	BASIX Review	Amended the DCR and LEP for controlling urban heat. The initiatives include cooling with landscape, colors and materials, building design and optimizing mechanical heating and cooling.
	Landscaped Areas	Proposed 7000 m2 city park with cooling features Social event ‘Where Shade Hits Pavement’;
	Urban Tree Canopy	Tree planting, tree assessment, Adopt a Tree initiative Monitored local heat with sensors; Conducted educational programs
Randwick Strategic Planning Draft Randwick [63,112]	Design Excellence Clause Development Control Plan	DCR amended to require heat island effect mitigation plans for new developments Planted 2250 trees; Secured $1.8M funding for tree planting
Ryde Ryde Resilience Plan 2030 vol 1 & 2 [113]	Integrate initiatives into strategic and management plans; Collaborate with other councils	-
	Provide funding for cooling initiatives	-
	Review controls for resilient buildings	-
	Develop a street tree masterplan	-
	Community Education	-
	Engage communities for resilient measures	-
Strathfield Strathfield 2040 local strategic planning statement [40,114]	Industrial & Urban Tree Planting	Initiated planting at industrial, rail, and urban services land; Industrial planting drive
	Green Infrastructure Implementation	Street tree maintenance program; Commenced tree masterplan for 100% canopy protection, monitoring, and expansion; Parks with on-site water retention
	Reflective Building Materials	Amended DCP for green infrastructure implementation; Required reflective materials and solar systems in new buildings
Sutherland Shire Open Space Strategy And Implementation Plan 2021–2031 [115]	Planting more trees within our open spaces open spaces to provide greater tree canopy for shade and cool.	-
Hillshire Environment Strategy [116]	Identify and target vulnerable areas for urban heat island effect mitigation through planting and education efforts	-
	Prepare informational material to raise awareness and prepare residents for environmental and urban risks	-
Waverly Waverley Local Strategic Planning Statement [117]	Prepare and implement an Urban Greening and Canopy Strategy	-
	Review controls for adaptable and resilient buildings	-
Willoughby Willoughby city council local strategic planning statement [118]	Increasing, monitoring and management of Tree Canopy	-
	Building Efficiency and Water features	-
Woollahra Woollahra Local Strategic Planning Statement [119]	Support collaboration and implementation of urban resilience initiatives	-
	Develop an urban resilience action plan for the area	-
City of Sydney Greening Sydney Strategy 2023 [28,42]	Tree Planting	Planted 910 trees
	UHI Monitoring	Conducted research on monitoring urban heat island effect
	Greening Initiatives	Planted green verge on footpath; Started ‘Greening Sydney Strategy’; Conducted community greening initiatives through community garden and city farm
Georges River Georges River Council’s Environmental Resilience Action Plan 2022–2040 [45,120]	Identify Vulnerable Areas	Work through Kogarah Collaboration Area process to identify areas with low urban canopy, high heat vulnerability, and high carbon emissions
	Tree Protection and Planting	Increased protection through Tree Management Policy; Funded planting of 500 trees through grant program
	ChillOut Hubs	Installed ChillOut Hubs to mitigate Urban Heat Island effect; Open-air community spaces with environmental sensors, mobile charging stations, Wi-Fi, and flexible work/rest spaces

). For instance, the City of Canterbury Bankstown aims to reach canopy targets of 40% in suburban areas, 25% in medium-high-density areas, and 15% in the council’s commercial centers by 2036 [35]. Currently, the canopy cover in its suburbs ranges between 10–20%.

Tree planting programs employ various approaches, including distributing native plants and trees to community members, securing grants for urban greening projects, engaging in community greening initiatives, and forming partnerships to enhance tree planting efforts and sustainability initiatives.

Strategically planning the expansion of canopy cover, councils are increasingly adopting an “Urban Forest approach”. This involves integrating urban greening initiatives into strategic plans and annual reports to monitor progress effectively. Moreover, councils are actively involved in community greening initiatives and advocating for sustainable policies to ensure long-term success in combating climate change and promoting urban resilience. For instance, Liverpool Council has launched an Urban Forest initiative to expand canopy cover, illustrating the importance of strategic planning and implementation in urban greening efforts. This approach has proven highly effective, with Liverpool’s urban canopy cover increasing from 0–10% in 2016 to 15–25%, according to council data [36].

Some of the investigated councils are adopting data-driven approaches to urban greening. This includes using tools to identify optimal tree planting locations, developing street tree masterplans that outline tree species, locations, and maintenance strategies, and implementing heat island mitigation strategies as part of new development regulations. For instance, Campbelltown Council stands out for its structured approach, beginning with a comprehensive analysis of tree canopy across the local government area and conducting heat mapping to guide tree planting efforts, resulting in the planting of 11,580 saplings [37]. Similarly, the City of Canada Bay follows a detailed plan based on its street tree masterplan, which outlines specific streets and tree species for planting, considering factors such as size, growth rate, and biodiversity [38]. Fairfield City Council’s use of Edge Impact’s Street Tree Prioritiser™ tool to identify optimal locations for tree planting is aimed at maximizing urban cooling and social benefits [39].

However, beyond planting, the maintenance of newly planted trees and existing canopy cover is crucial. Councils such as City of Canada Bay Council, Strathfield, and Inner West have initiated tree management programs to ensure ongoing maintenance [38,40,41]. Moreover, councils that have secured grants for their greening programs, such as the Parramatta, Sydney, and Randwick councils, highlight the pivotal role of funding in expanding the scope and impact of urban greening efforts. These initiatives focus on tree planting and maintenance, community engagement, and policy advocacy, illustrating a comprehensive approach to creating resilient and livable urban environments.

For example, the City of Parramatta Council has efficiently allocated funds to enhance public cooling through various services, engaging stakeholders in tree planting, maintenance, and mapping vulnerable spots. Similarly, the City of Sydney has undertaken multiple actions to increase green cover, conducting detailed studies of existing and recent (2022–2023) canopy cover. Through community greening initiatives and tree-planting efforts, the council raised the local government’s green cover from 15.5% in 2008 to 19.8% in 2022 [42].

Randwick Council secured AUD 1.8M from the Greening Our City program to plant approximately 2000 trees across vulnerable suburbs, with plans to increase canopy cover from 16% to 40% by 2040. Government funding also supported Penrith City Council’s expansion of tree planting projects across streets, parks, industrial estates, and major corridors throughout the local government in 2022 [43]. Camden Council, aiming to increase canopy cover from 15% in 2019 to 25% by 2024, has planted 1800 trees in vulnerable locations using the Heat Vulnerability Index proposed by the NSW government [44]. The monitoring of this initiative is yet to be made available. Furthermore, Georges River Council [45] has utilized funding from the “Five Million Trees for Greater Sydney” grant to plant over 500 new trees. These examples underscore the critical role of funding in implementing, sustaining, and scaling up efforts to enhance canopy cover in urban areas.

Some councils are making commendable efforts towards urban greening, whereas others, like Burwood Council, Sutherland Shire Council, and Hillshire Council, fall short due to a lack of comprehensive implementation and maintenance plans. Effective urban greening requires more than ambitious targets and tree planting; it necessitates detailed strategies for ongoing care and prioritization. For instance, Burwood Council’s 2022–2023 strategy plan proposed a street tree masterplan [46], but the council’s annual report indicates no progress toward this goal. Despite the council’s planting of over 500 trees, the report [47] lacks details on how the planting locations were selected. This highlights the critical need for well-rounded plans that ensure both the establishment and the sustained health of urban green spaces, rather than merely setting goals for increasing canopy cover or planting trees.

In conclusion, while the strategies adopted by councils to improve their green cover are commendable, the success of these initiatives relies on an implementation plan that encompasses planting, maintenance, and community involvement beyond the tenure of the funding. Despite the substantial benefits of urban greenery, the effectiveness of these efforts in climate change mitigation can be significantly influenced by factors such as climate, season, plant morphology, placement, and irrigation levels [48].

Unrestricted water supply enhances the cooling potential of plants, whereas restricted water supply, poor irrigation conditions, and scarce precipitation can adversely affect evaporative cooling [49]. Additionally, excessive heat stress due to urban overheating may limit the effectiveness of leaf stomata [49]. The literature indicates that urban trees can reduce peak ambient temperatures by 0.1 °C to 4 °C, with a median value close to 1.5 °C [50]. Areas directly shaded by trees present the best thermal comfort conditions, with surface temperatures up to 15 °C lower than those in unshaded areas [13]. In addition, irrigation is a key factor in achieving a considerable mitigation effect for vegetation-based mitigation strategies, particularly in hot, arid conditions, with reductions in peak day-time temperatures of up to 0.7 °C and of night temperatures of up to 2.1 °C [51]. Therefore, to maximize the cooling and mitigation potential of urban greenery, it is crucial to implement comprehensive strategies that ensure proper irrigation and maintenance. By addressing these factors, councils can enhance the resilience and sustainability of urban green spaces, effectively contributing to climate change mitigation and the creation of livable urban environments.

3.1.2. Building Design, Materials, and Regulations

The thermal balance of urban areas is highly affected by the thermal properties and the characteristics of the materials used in the building envelope and the urban fabric, as well as urban development and building typologies. Among the diverse strategies employed, councils are actively focusing on innovative building design and materials initiatives, including the following:

• Cooling materials and sealants;
• Shaded structures and green roofs/walls;
• Sustainable building design and development controls.

Councils prioritize sustainable building practices and materials to mitigate climate change and enhance energy efficiency. Key measures include incorporating cool materials for pavements and roofs, promoting the use of reflective materials, and enhancing building insulation to reduce surface temperatures and mitigate UHI effects (see Appendix B; Table A1). For instance, Campbelltown Council implemented a seal coating on road surfaces called “CoolSeal”, originally imported from the United States for trial in Sydney. This application on car park surfaces demonstrated significant temperature reductions: daytime temperatures decreased by 5.6 °C and nighttime temperatures decreased by 2 °C. The monitoring also showed mean surface temperature reductions from 41.2 °C (±6.9) on uncoated roads to 35.3 °C (±6.0) on coated roads (impact sites), resulting in a −0.4 °C air temperature differential [52]. Despite enthusiasm for cool roads, most council roads remain in plain bitumen due to financial constraints [53]. Budget limitations often hinder councils, especially in low-income areas, from investing in expensive heat-mitigating measures like advanced reflective sealants. The high cost of CoolSeal, approximately AUD 15 per square meter, poses a significant barrier given the extensive road surfaces involved, limiting its widespread application. A potential solution could be developing a locally tailored cool sealant suitable for Australian climatic conditions, offering a more cost-effective option for councils to address urban heat challenges.

Another measure for heat mitigation is the installation of pale roadways, as suggested by Bayside Council [54], although no concrete deadlines or progress reports have been provided regarding temperature reductions from this measure. Compared to CoolSeal, this approach may be more cost-effective [53].

In addition to cooling materials and sealants, councils are implementing shaded structures as part of urban cooling treatments in play spaces and parks, as documented in action reports by Parramatta Council [55]. Burwood Council’s strategy plan includes utilizing both constructed and natural shade, with the introduction of shaded umbrellas in public areas further advancing these efforts. Similarly, Cumberland Council installed a Trellis system over parking lots to mitigate UHI impacts while exploring sustainability and cost-effectiveness. The council also implemented a UV Smart Cool Playground, thermal resistance shade improvements, and enhanced tree canopy cover as part of its urban cooling actions [56]. Inner West Council enhanced car parks by incorporating tree plantings and gardens as part of their heat reduction policy [41]. Penrith Council proposed replacing asphalt parking lots with multi-deck parking structures covered in green walls and green roofs [43].

The councils of the City of Canterbury Bankstown and Cumberland City have mentioned adopting sustainable building materials as part of amendments to development control legislation [57,58], but there are no documents showing progress toward this aim. In contrast, Penrith Council has taken a leading role among councils by introducing a new Urban Heat chapter into the Development Control Plan (DCP, 2014) [59] and implementing new cooling measures, including the use of cool colors and materials [60]. The council mandates that material and finish schedules for any new development include specifications for product energy-efficiency properties, such as thermal mass, airflow impact, appropriate color and reflectivity, and material permeability, in landscape design. The Penrith DCP, 2014 emphasizes roof properties, such as the solar reflective index and roof color. For walls, car-parking spaces, driveways, and landscaping, it recommends using materials with high albedo or reflectivity. In pedestrian areas without shade, medium-colored materials with high thermal emittance (which release heat quickly) and/or permeable materials are proposed for use [59].

Although the above-mentioned councils have implemented records on optimizing materials for heat mitigation, there are no records documenting site selection for the implementation of these strategies, except for the CoolSeal project. The City of Parramatta and Blacktown councils further support evidence-based interventions for urban cooling on Philip Street [13] and Mount Druitt [61], respectively, by simulating temperature changes due to changes in material type.

Several councils across Sydney have mandated specific actions and outlined potential measures for heat mitigation. For instance, the councils of Blacktown and Penrith have mandated design and building requirements to reduce water use and mitigate UHI effects [62]. Randwick Council requires a UHI mitigation plan to be included in each new development [63]. Additionally, the Parramatta and the City of Sydney councils have mapped heat within their areas and collaborated with academic institutions to track the UHI effect [42,55], setting examples by incorporating heat mitigation measures into their policy initiatives.

Although councils are taking proactive steps to address UHI challenges through innovative strategies and pilot projects, there is a need for more comprehensive monitoring, evaluation, and cost-effective solutions to ensure widespread adoption and long-term effectiveness across various councils. Councils that have amended the DCP are making determined strides toward mitigating UHI. Incentives and funding to incorporate heat mitigation measures (e.g., by changing material types) should be further explored. Additionally, while some councils propose innovative solutions like green roofs and walls, the implementation of these strategies remains sparse, indicating the need for enhanced funding commitment and progress-tracking toward achieving canopy cover goals.

Cool roof adoption is commonly proposed as a heat mitigation measure. However, the adoption of green roofs in Australia has been hindered by barriers such as plant selection, maintenance costs, and safety concerns [64]. Cool roofs offer benefits like thermal comfort and energy savings (significant reductions in hourly cooling loads/peak electricity load) but face challenges such as increased heating load in colder climates and dirt accumulation [65].

3.1.3. Community Engagement and Education

Engaging and educating communities about climate change risks and mitigation strategies is integral to local government-led initiatives. Community education programs and awareness campaigns empower residents to adopt practices that reduce heat exposure and enhance urban resilience. Eight of the thirty councils have made significant progress in implementing measures aimed at involving communities in heat mitigation efforts (see Appendix B; Table A1).

These community-focused activities include creating cool and engaging public spaces to help residents cope with heat. For instance, the City of Canterbury–Bankstown has developed the “Greenacre Splash Park”, a communal water park that offers free summertime relief as part of the council’s strategic action plan [57]. George River Council has installed “ChillOut Hubs”, open-air community spaces equipped with environmental sensors, mobile charging stations, Wi-Fi access, and flexible work and rest areas to mitigate UHI effects [45]. Blacktown Council has established “Cool Centres” with community engagement activities and refreshments, doubling as heat shelters during intense weather [55].

Councils have implemented diverse educational and community initiatives to help residents cope with and mitigate the effects of heat. In Campbelltown Council, primary-school students learn about local species, while heat mapping results are shared with the community to raise awareness about heat protection [37]. Cumberland Council uses the Heat Smart Toolkit by WSROC, providing services and water filling stations for vulnerable groups during hot days, alongside community awareness efforts through signage [56]. They also designate shelter locations like libraries, pools, and community centers during heatwaves, effectively implementing toolkit strategies [55]. Canada Bay Council educates residents on tree maintenance through online resources [38]. Similarly, Penrith Council organizes workshops and collaborates with businesses to discuss heat mitigation strategies [43]. The City of Sydney supports community gardens and Sydney City Farm as valuable public resources [42].

Understanding community perceptions, preferences, and concerns is crucial for designing effective cooling strategies in urban areas. Studies suggest that residents value green spaces near water bodies for their perceived naturalness and orderly environment, contributing to health and well-being [66,67]. Generational differences also influence preferences, with older residents prioritizing green spaces and younger individuals emphasizing temperature reduction in urban environments [68,69]. Tailoring greening efforts to these preferences can enhance the inclusivity and effectiveness of cooling strategies.

3.1.4. Water Sensitive Urban Design (WSUD)

Water has always been a key cooling strategy for urban areas at risk of overheating. Water management is vital for climate change mitigation in urban areas, as conventional stormwater systems often drain rainwater too quickly, leaving cities unnaturally dry. By implementing effective water management strategies, cities can retain more water within the urban environment, reducing heat and enhancing resilience. Water management technologies, such as bio-filtration systems, rain gardens, and constructed wetlands, not only manage stormwater but also provide cooling benefits, improving urban livability and sustainability [4]. WSUD has emerged as a critical approach in addressing the following:

• Stormwater management initiatives;
• Water reuse and irrigation;
• Water monitoring and conservation.

Four councils are actively pursuing water efficiency measures to mitigate urban heat (see Appendix B; Table A1). Blacktown Council, for instance, employs water-sensitive planning by implementing projects like stormwater harvesting at Angus Creek. This initiative treats rainwater for reuse in irrigation at locations such as Blacktown International Sportspark, reducing reliance on potable water and maintaining green spaces. Additionally, rain gardens and wetlands at Blacktown Showground contribute to sustainable water use for community gardens and park upkeep. The council has also established guidelines for inspecting and maintaining WSUD to ensure effective water resource management [70]. To enhance water availability for heat mitigation, Blacktown Council monitors water usage, and it has established design and construction guidelines aimed at reducing water consumption. Camden Council has adopted operational guidelines for WSUD, drawing inspiration from Blacktown Council’s approach. Their strategy includes vegetated buffer strips, swales, and on-site stormwater detention to mitigate urban heat [44]. However, there is a lack of evidence supporting the implementation of all WSUD measures post-establishment.

In 2006, Liverpool Council installed over 236 water meters to monitor water consumption across parks and buildings as part of their conservation efforts [36]. However, no additional water meters have been installed since 2006, and the council lacks updated water audit reports to assess consumption trends amidst population growth and to manage excess demand.

Strathfield Council transformed Hudson Park into a district park with an on-site retention basin, ensuring water self-sufficiency even during hot weather [40]. Similarly, Inner West Council proposes the retention, infiltration, and promotion of water and water bodies within the landscape [42]. This approach could potentially be replicated in other community parks.

The SIMPACT project at Bicentennial Park utilizes artificial intelligence for smart irrigation management using recycled water. In the scope of this project, the real-time monitoring of soil moisture, air temperature, and weather forecasts optimizes water distribution, cooling public spaces, and promoting sustainable water management [71].

Although some councils (i.e., the City of Canterbury Bankstown (CB City Council), North Sydney) have proposed various interventions for WSUD in their strategies, this was not reflected in their action plans showing any progress towards such initiatives.

Research on the microscale cooling effects of WSUD and irrigation [4] highlights the importance of targeted interventions. By understanding urban climate microclimates, planners can design WSUD systems that harness cooling benefits effectively. Incorporating water-sensitive design elements, such as permeable surfaces and green spaces, into land use planning promotes local cooling and enhances overall urban resilience to heat stress. Additionally, Bartesaghi-Koc et al. [72] highlight the importance of surface wetness and irrigation in enhancing the cooling effect of green infrastructure types. Integrating water features like irrigation systems into urban greenery planning can optimize the cooling capacity of green spaces, further reducing UHI effects and improving thermal comfort for residents.

3.2. Challenges and Barriers in Implementing Urban Cooling Strategies

Here, a comprehensive analysis of the obstacles faced by councils in their efforts to mitigate and adapt to climate change based on the outcomes of interviews conducted by the representatives is provided.

3.2.1. Policy-Level Barriers for Heat Mitigation

One major barrier identified during the interviews is the absence of specific regulations within the National Construction Code (NCC) addressing extreme heat events. While NCC focuses on thermal considerations primarily for energy efficiency, it lacks explicit guidelines for mitigating the impacts of extreme heat on buildings. This gap underscores the need for regulatory amendments to incorporate measures that ensure thermal comfort and energy efficiency during heatwaves [73]. The lack of direct local government authority over much of the urban planning system was also indicated during the interviews. BC Council mentioned the following:

“Though the councils can provide ideas, evidence and a degree of influence, it is the responsibility of the Commonwealth Government for the NCC which mandates the minimum requirements for a building’s shell, and NSW Government sets the rules and framework for most of the urban planning”.

A similar response was reflected by PC Council mentioning the “Lack of power in planning processes”. They also stated an example “where council’s Local Environmental Plan/DCPs can be overridden by the State Government State Environmental Planning Policies, or council cannot require development to go above and beyond Building Sustainability Index (BASIX)”. Another case to be considered is that of rural and remote areas. Building regulations in areas aimed at mitigating extreme weather impacts often lead to increased costs and design limitations. The lack of comprehensive regulations specifically addressing overheating in buildings is notable, considering the vulnerability to extreme heatwaves [74]. This gap indicates a need for more nuanced policies tailored to diverse geographic contexts.

A low prevalence of supportive policies and incentives to promote the adoption of green infrastructure, like living green walls and green roofs in urban environments, was also indicated. The disparity in local governments’ levels of awareness, scarce explicit policies promoting green infrastructure, and the predominance of living green wall and green roof installations in commercial settings highlight the need for comprehensive and uniform policies to encourage green infrastructure development across diverse urban contexts. Comparative research on mandatory and voluntary approaches to green roof implementation underscores the complexity and variability in policy frameworks across Australian cities [75]. While a mix of voluntary and mandatory policies is suggested [75], inconsistencies in incentives [76], accreditation avenues [64], and financial support [77] contribute to challenges in fostering the widespread adoption of green infrastructure for heat mitigation. This highlights a critical barrier in promoting green infrastructure as a viable heat mitigation strategy.

The interviews with the councils provided evidence that some councils are ready to take a proactive approach toward promoting urban cooling strategies through regulatory measures, aiming to enhance the sustainability and resilience of urban environments. For instance, the interview with council BC found that they are “investigating options for inclusion of cooling strategies in their updated DCP such as requiring a suitable minimal solar roof index rating”. Additionally, the council has proposed “……to develop planning controls such as reflective roof finishes, porous paving and increasing green/blue infrastructure as urban cooling interventions for future urban design and development”.

On the other hand, PC council stated that “(they) developed Urban Heat Planning Controls Package, which includes an amendment to the PC Local Environmental Plan 2010, introducing the urban heat chapter which includes controls to achieve cooler, more thermally comfortable buildings and cooler outdoor spaces”… (in addition) “Planning for Heat Issues Paper in consultation with developers, planners and other stakeholders to advocate for changes to state planning system to better address urban heat was developed”.

Addressing these policy-level barriers requires a coordinated effort involving regulatory updates, enhanced government support and incentives, streamlined housing regulations, harmonized policy approaches, and accelerated progress in policy development and implementation. Collaborative initiatives involving policymakers, researchers, industry stakeholders, and communities are essential to overcome these barriers and advance effective heat mitigation strategies in Sydney.

3.2.2. Knowledge-Based Barriers to Planners’ Awareness for Heat Mitigation

While there is a general awareness among planners about the impacts of extreme heat, their usage of heat mitigation techniques in practice remains lower than that of design-centric professionals [78]. This disparity suggests a knowledge gap, or perhaps a lack of prioritization for heat mitigation measures within planning practices. For example, the interview with PC council found that “Lack of knowledge of urban cooling strategies and/or lack of good demonstration sites, and learnings from on-ground examples may mean council is hesitant to trial/put in place new cooling strategies”. This challenge is compounded by the current reliance on manual monitoring processes for green infrastructure, which can hinder the ability to effectively assess and optimize heat mitigation strategies. As noted by CL council, “It’s a bit challenging. It’s a manual process, not automated. We don’t have sensors or anything like that at the moment to assist us. We have to physically go out and monitor the green walls, and that’s part of our maintenance process to ensure that they’re still performing as expected”.

Planners predominantly rely on local government planning schemes. However, there are mixed views on whether the current planning framework adequately facilitates the implementation of heat mitigation strategies. The effectiveness of these strategies is often undermined by the lack of advanced monitoring tools, which impedes the ability to assess and optimize interventions accurately. As a result, addressing both knowledge-based barriers and the need for improved monitoring methods is crucial for fostering a more climate-responsive approach and effectively mitigating heat-related challenges in Sydney.

3.2.3. Impact of Land Use Planning on Heat Mitigation Strategies

Effective land use planning that integrates green and blue spaces, balances development intensity, and considers climate-responsive design is critical for implementing successful heat mitigation strategies. Councils are also looking to develop policy-level interventions for different types of land use. For example, the PC council has already “amended the DCP 2014 with a strategy that has slightly different controls for residential vs. industrial zones for example with respect to tree planting (location, size and number of trees, deep soil zones etc.)”. The SC council has adopted a range of measures in a draft DCP, emphasizing land use policy through the documentation of “Tree planting and deep soil provision on private land as well as the strategies for planting on public land to increase canopy cover and ensure development provides sufficient deep soil and space above ground for the viability of new and existing trees, along with directives for providing green roofs wherever possible”.

Land use planning, including transport (or transit)-oriented development (TOD) and employment and residential density areas, play a crucial role in shaping effective heat mitigation strategies. Several research papers provide valuable insights into complex relationships between development patterns and heat [79,80,81,82]. While TODs offer benefits like reduced greenhouse gas emissions and enhanced social connectivity, they also contribute to higher temperatures and a more pronounced UHI effect compared to non-TOD areas over time [79,83]. This highlights the need for balancing development intensity with green space provision to promote cooling effects.

Different policy scenarios, such as compact development, TOD, infill and sprawl development, and balanced green space distribution [84,85] demonstrate varying degrees of effectiveness in controlling the UHI effect [86,87]. Land use planning that integrates green infrastructure can maximize the cooling benefits while addressing water management challenges in urban areas [88].

3.2.4. Technological and Finance Barriers for Cooling Strategies

Implementing cooling strategies in urban environments faces technological and financial barriers that influence their feasibility and adoption. High ongoing maintenance costs and occupational health and safety issues related to manual maintenance limit their widespread implementation [89]. As indicated during the interview with PC council, “It is also seen that often the sustainability/climate mitigation strategies are removed from the design if any financial challenges arise, (to mitigate these challenges) council has also developed its own Council Buildings Policy which includes sustainability, resilience, cooling and climate adapted building criteria for new and refurbished buildings over a specific cost threshold that are owned/managed by Council. Council has in place its own Sustainability Revolving Fund which is a mechanism to fund Council projects with sustainability/resilience outcomes”.

Additionally, CL council emphasized that financial constraints also impact the monitoring of implementation plans, stating that “The lack of budget for monitoring processes often means that the impact and effectiveness of implemented cooling strategies are not thoroughly assessed”. This lack of financial support for monitoring hinders the ability to understand and improve the effectiveness of these strategies. Furthermore, the council pointed out the importance of community engagement and the challenges faced in this area: “Financial barriers can also affect the ability to support and follow up on community engagement programs. Without adequate funding, it is difficult to assess whether these engagement efforts are successful and to make necessary adjustments based on feedback”. This highlights the need for more robust financial support to ensure that engagement programs are effectively implemented and evaluated.

4. Discussion and Conclusions

This study explored the urban cooling measures prioritized by governmental bodies in Sydney, Australia. The official documents and policy statements of 30 councils were reviewed and interviews were conducted with council representatives. The implementation processes and challenges related to heat mitigation initiatives were analyzed accordingly.

The desktop review revealed that the councils have adopted four key categories of urban cooling strategies, each underpinned by specific toolkits and development-control regulations. The map illustrates the councils’ commitment to heat mitigation, color-coded based on their implementation levels: red for councils reporting one out of four measures (e.g., Fairfield, Hunters Hill) and blue for those implementing all four measures (e.g., Blacktown, Penrith) (Figure 3).

It can be inferred that councils with more resources (higher SES, Figure 1) and those facing significant urban heat risks (i.e., Western Sydney) are generally more proactive in implementing heat mitigation measures. Councils in higher SES categories and those in high-urban-heat-risk areas tend to be more comprehensive in their approach. Penrith and Blacktown exemplify this trend, having adopted all four measures due to both their financial resources and substantial urban heat risks.

Conversely, councils with lower SES, such as Fairfield, show less comprehensive adoption despite facing urban heat risks, indicating potential resource limitations. This disparity highlights how both financial capacity and urban heat risk influence the extent of heat mitigation efforts, with more affluent and high-risk councils generally demonstrating greater proactivity.

Key aspects related to the implementation processes in climate mitigation initiatives, as well as the associated challenges and opportunities, are addressed below.

Challenges and Barriers:

Disconnection between planning and implementation has been revealed as a significant gap between the proposed climate mitigation measures by councils and the documented progress in implementing these measures. Despite councils outlining various strategies in their plans and policies, the actual execution and progress are often not well-documented. Critical details such as specific targets, action plans, and measurable outcomes are frequently missing, making it challenging to assess the impact of these strategies. For instance, councils propose extensive tree planting programs and set targets to increase tree canopy cover, yet they often do not provide documentation of progress towards achieving these goals. This highlights the pressing need for greater transparency, accountability, and comprehensive documentation to ensure meaningful progress towards creating resilient and sustainable urban environments capable of effectively addressing the challenges posed by UHIs.

A monitoring framework to connect the planning and implementation of these initiatives is required. The absence of such a system hinders stakeholders from effectively tracking progress and making data-driven decisions to enhance resilience against urban heat challenges.

Financial barriers associated with monitoring and maintaining climate mitigation initiatives pose significant challenges to their long-term effectiveness and adoption. Implementing strategies like cooling technologies and WSUD requires substantial initial investments and ongoing operational costs, which many councils find difficult to sustain without dedicated funding mechanisms. For instance, high maintenance expenses and concerns over occupational health and safety often deter councils from fully embracing these initiatives [90]. Moreover, during budget constraints or competing priorities, sustainability measures can be sidelined or scaled back, as noted in discussions with the PC council. Some councils have developed their own policies and funds to prioritize sustainability in building projects, such as the Sustainability Revolving Fund [43]; however, these resources are often limited and may not cover all the necessary interventions or ongoing monitoring needs. The gap between proposed strategies and actual implementation, as shown by the discrepancies in the action plans, underscores the need for robust financial support and strategic oversight to ensure sustained progress in climate mitigation efforts.

Policy-level and technological barriers and knowledge gaps have been highlighted as critical in implementing urban cooling strategies in Sydney. The lack of specific regulations addressing extreme heat events and limited government support for green infrastructure hinder effective heat mitigation efforts. Technological barriers, such as retrofitting challenges, like cool materials, green walls and roofs, and their adoption limitations, underscore the need for innovative solutions to optimize cooling strategies’ performance. Additionally, there is a knowledge gap among planners regarding heat mitigation techniques, highlighting the need to integrate these strategies more comprehensively into planning frameworks.

Opportunities:

Alignment with state- and national-level policies is crucial for creating coherent and effective responses to urban heat. For instance, the “Pulse of Greater Sydney 2020” report by the Greater Cities Commission [91] and the AdaptNSW program [92] provide valuable insights and case studies on urban heat and the heat island effect, offering strategies that are consistent with the broader policy framework.

The NSW government has set recommendations for adapting to increased urban heat, which include reducing greenhouse gas emissions, increasing green cover, designing with water, adapting buildings and infrastructure, and providing refuges from heat. These recommendations align closely with the strategies identified in councils’ plans across Greater Metropolitan Sydney. Initiatives like the “Greener Places” framework [93] and guides such as “Minimising the Impacts of Extreme Heat—A Guide for Local Government” [94] reflect the integration of state-level policies into local cooling strategies.

Collaboration is a key aspect highlighted in both initiatives, as evidenced by the involvement of multiple stakeholders in the development of their respective action plans. For instance, regional efforts like “Resilient Sydney” [28] and “Turn Down the Heat” [29] illustrate a collaborative approach that involves multiple stakeholders and promotes consistency with state and national climate policies, further ensuring that local strategies contribute to broader climate resilience goals. Resilient Sydney [28] engages 33 councils across the metropolitan area, while Turn Down the Heat [29] involves over 55 stakeholders in Western Sydney.

Engagement with the community is crucial for effectively managing and maintaining heat mitigation measures and understanding residents’ preferences for designing inclusive and sustainable cooling initiatives. The examples above illustrate how councils initiate projects to use people as resources to reciprocate measures for heat mitigation through awareness and community participation. This fosters a sense of collective belonging and responsibility towards curbing heat. Through free access to water parks and public spaces, the councils work to create inclusivity. Although some councils have demonstrated projects, while others lack them, adapting to the idea of demonstration projects in collaboration with community groups can showcase the effectiveness of heat mitigation measures. This can help build trust and support among residents by demonstrating tangible results. Furthermore, for effective community engagement and education programs, establishing feedback mechanisms such as surveys, suggestion boxes, and community meetings to gather input from residents regarding their experiences with heat mitigation measures can help councils to track and monitor effectiveness from community perspectives. This feedback can be used to improve and adapt strategies based on community needs and preferences.

Preparedness refers to the extent of the alignment of local government policies with established best practices and resilience measures for climate adaptation. Focusing on Sydney, a socioeconomically and culturally diverse international city, this study provides a preliminary assessment of its preparedness to address climate change risks. This includes assessing the comprehensiveness of climate action plans, the integration of adaptation strategies, and the effectiveness of policy implementation. While a specific degree of preparedness is not quantified, the findings offer a qualitative assessment of how well the city’s approaches align with recognized standards for climate resilience. The insights gained from Sydney can inform and guide mayors and local governments across Australia and beyond, facilitating the development of robust, localized strategies for enhancing resilience and sustainability in the face of a changing climate.

Success stories and global examples worldwide are increasingly helping to set specific heat reduction targets as part of climate strategies. To effectively manage and communicate their heat mitigation efforts, cities around the world have established specific heat reduction targets as part of their broader climate strategies. These targets are often linked to both heat mitigation approaches and measurable temperature reduction goals, serving as benchmarks to guide and evaluate progress.

For example, Los Angeles’ Sustainable City Plan 2019 seeks to minimize the urban–rural temperature gap by at least 0.94 °C by 2025 and 1.67 °C by 2035. This ambitious aim is supported by citywide targets for cool roofs and pavements [95]. Similarly, Melbourne’s Urban Forest Strategy aims to cool the city by 4 °C by doubling tree canopy cover by 2040, which would require planting at least 3000 trees per year [96].

New York City’s Million Trees NYC program, which began in 2007, successfully planted one million trees by 2015, two years ahead of schedule, proving the value of setting specific, measurable goals [97]. In Paris, the climate action plan includes goals for developing green spaces, such as adding 30 hectares of public green space, 100 hectares of vegetation on walls and roofs (one-third of which will be dedicated to urban agriculture), and planting 20,000 new trees [98].

Barcelona’s Climate Plan 2018–2030 aims to deliver 1 m² of greenery per citizen by 2030, resulting in 160 hectares of additional green space by the end of the plan [99]. These examples demonstrate how cities intentionally define and pursue heat reduction targets to improve urban resilience and sustainability.

One limitation of this study is the participation rate in the interviews. Eight proactive councils were invited to conduct the interviews and five of them agreed to participate, which could have impacted the generalizability of the results. The insights gathered from this limited engagement are partial and may not fully represent the broader spectrum of strategies and challenges faced by all the councils in the metropolitan area.

Future research could include a broader and more representative range of councils to ensure a comprehensive understanding of urban heat mitigation efforts across different contexts. This would provide a richer dataset, capturing a diverse array of experiences and strategies. Additionally, longitudinal studies could be undertaken that track whether and how these strategies have been applied in practice, and future studies could utilize maps and images to compare the intended outcomes with the actual results, which would offer valuable insights into the potential gaps between planning and execution. By addressing these limitations, future research can build a more robust evidence base to inform policy and practice, ultimately enhancing the resilience of metropolitan areas to urban heat and climate change.