Search

Collaboration is strongly promoted as an effective means for cities to respond to climate change. While collaboration is perceived to offer opportunities to progress climate action in cities, little is known about how collaboration can enable low‐carbon transformation in practice. Furthermore, while collaboration is largely framed as a positive endeavour, there is a need to more carefully explore the challenges and barriers that may arise. This paper explores the aims, processes, and outcomes of collaboration within urban climate governance. Drawing on a policy review and semi‐structured interviews, we present empirical findings from the case study of Hong Kong. This paper identifies three types of collaboration that are structured by regulations, oriented to policy goals, and emerge as everyday practices within the governance of climate change and the energy system. The forms of collaboration challenge the assumptions that collaboration always brings positive outcomes in mobilising action for climate change. While collaboration opens up different modes of governance within cities, the paper highlights significant barriers in terms of the diverse roles of actors, ongoing power imbalances, and shifting governance spaces for intervention. Given the prevailing interest in working together, it is critical to review carefully how collaboration facilitates cities to achieve their climate goals and create momentum for action. The paper explores the opportunities and challenges of collaborative climate governance. It draws on a case study of Hong Kong and identifies three modes of collaborative climate and energy governance: regulatory, consensual, and participatory. The paper challenges the assumption that collaboration brings positive outcomes for action on climate change and offers new insights into potential barriers for climate action in cities. [ABSTRACT FROM AUTHOR]

The role of cities in mobilising transformative change has gained increasing attention in global discourses on climate change and sustainability. Through the lens of urban energy transitions, this paper focuses on how this form of change within the urban energy system can be mobilised. Capacity is an emergent concept and has been adopted to identify areas for change and assess the transformative potential of cities. Connecting three dimensions of capacity: capacity for what, capacity of whom and the process of capacity building, we present a new conceptual framework to understand diverse transition pathways. To interrogate the capacity framework in practice, we explore the illustrative cases of Hamburg and Hong Kong. The paper demonstrates that capacity is connected to specific changes in political, material, institutional and other energy‐related societal contexts. Understanding the variety of dependencies and underlying challenges within urban energy systems , as well as the kinds of actor coalitions that are capable of addressing such complexity and mobilising change, enables the development of specific socio‐technical solutions for urban energy transition pathways. Our focus on local capacity to act and how such capacity can be expanded or diminished contributes to a deeper understanding of the power relations embedded in urban energy systems and the role local actors can play in enabling and hindering processes for change. Such examination of how complex trajectories for change are defined and shaped allows significant insights into plausible futures of urban development. [ABSTRACT FROM AUTHOR]

The combined impacts of COVID-19 and global climate change are destabilising the infrastructures and future prospects of formal educational systems, with schools and universities struggling to adapt to conditions of radical precarity. At the same time, activist movements are generating alter-educational platforms that reappropriate the learning infrastructures of cities as mobile architectures of pedagogical resistance. Building on Harney and Moten's The Undercommons, this paper discusses transnational examples of radical pedagogies that engage the city as an ecology of deformalised study. We highlight examples from Melbourne's COVID-19 lockdown regime, emphasising how informal study enabled community-led responses to crisis at city-scale. We then turn to urban ecologies of study arising from contemporary activist movements, drawing connections between protest movements in Hong Kong and Deleuze and Guattari's concept of the 'war machine'. This leads to a speculative re-imagining of alternative educational values and futures within a milieu of activist study, care, and resistance. [ABSTRACT FROM AUTHOR]

The combination of dense urban development, hilly terrain, and intense seasonal rainfall has caused acute landslide problems in Hong Kong, which are manifested by a death toll of over 470 people since the late 1940s. Tackling landslide problems in an urban setting, in particular under the effect of climate change, calls for a development and implementation of a holistic risk management strategy. It entails the use of engineering and non-engineering approaches, involving policy, legislative, administrative, innovation, technical, educational, community-based, and emergency-preparedness provisions. In this paper, these two approaches are showcased by the slope safety system that has been developed and promulgated in managing landslide risk for building Hong Kong as a world-class smart city. [ABSTRACT FROM AUTHOR]

Nine engravings in the hinterland around Hong Kong Island have been studied independently by the authors, as part of an overall assessment of current management practices, the state of the engravings, conservation impacts and future survival. Four independent studies were commissioned in 2009 by the Hong Kong Heritage Museum in conjunction with the Antiquities and Monuments Office who have legislative responsibility for all archaeological sites within the Hong Kong Special Administrative Region. The sites have received varying levels of protection in the form of roofs, fences, and screens, and in more recent times, a range of conservation treatments aimed at prolonging their life and improving legibility. This paper reviews the state of the engravings from the point of view of protection and presentation and considers the effectiveness of the infrastructure in mitigating what are often conflicting needs. Modern conservation treatments must be considered in several dimensions: their effectiveness and durability in an aggressive climate, given that the engravings have survived for 3000 years, and the feasibility and cost of maintaining such treatments over the next 3000 years and longer. This paper describes field observations rather than measured data, due to the nature of the commission, highlighting the value of intelligent observation as an investigative tool. The main focus of the paper is on the impact of protective shelters and applied treatments as observed during two of the independent surveys, concluding that protection must address all environmental and visitor impacts to be fully protective. [ABSTRACT FROM AUTHOR]

Cities have increasingly become the focal point for climate change initiatives. However, how cities respond to climate change challenges and through what mechanisms have remained largely unexplored. This paper develops a framework for local governance to examine and explain climate change initiatives in cities. Based on the analysis of 20 climate change initiatives in major cities and a detailed case study of Hong Kong, this paper has two main findings. First, local governments at the city level have an important role to play in climate change policies by embracing some key strategies (such as deliberation and partnership) and values (such as equity and legitimacy) of good governance. Second, by comparing and contrasting the experience in other cities, our case study of Hong Kong provides insights about the barriers that may limit a city's ability to adapt to new forms of governance that would enable it to better respond to climate change. The paper concludes by exploring the potential role of local governance as a model to strengthen climate change initiatives at the city level. [ABSTRACT FROM PUBLISHER]

Though there has been an increased focus on climate change in Hong Kong's educational policy and curriculum over the last decade, little is known about the impact of curricular implementation on young people's environmental and climate change-related views, attitudes, awareness, or behaviors. This paper examines the state of climate change education in Hong Kong based on findings from a multi-pronged investigation. The main research questions addressed are: (1) what are Hong Kong secondary students’ understandings of and attitudes towards climate change issues? and (2) is there any significant difference between students studying in local and international schools in Hong Kong? The paper provides a content analysis of climate change curriculum in local and international schools. It reports on a large-scale survey of international and local school students’ environmental attitudes, and on qualitative interviews of their awareness and behaviors related to climate change. We conclude with reflections on the implications of this study for climate change education in Hong Kong in the future and vital areas for further research. [ABSTRACT FROM AUTHOR]

This paper presents the findings of an outdoor thermal comfort study conducted in Hong Kong using longitudinal experiments-an alternative approach to conventional transverse surveys. In a longitudinal experiment, the thermal sensations of a relatively small number of subjects over different environmental conditions are followed and evaluated. This allows an exploration of the effects of changing climatic conditions on thermal sensation, and thus can provide information that is not possible to acquire through the conventional transverse survey. The paper addresses the effects of changing wind and solar radiation conditions on thermal sensation. It examines the use of predicted mean vote (PMV) in the outdoor context and illustrates the use of an alternative thermal index-physiological equivalent temperature (PET). The paper supports the conventional assumption that thermal neutrality corresponds to thermal comfort. Finally, predictive formulas for estimating outdoor thermal sensation are presented as functions of air temperature, wind speed, solar radiation intensity and absolute humidity. According to the formulas, for a person in light clothing sitting under shade on a typical summer day in Hong Kong where the air temperature is about 28°C and relative humidity about 80%, a wind speed of about 1.6 m/s is needed to achieve neutral thermal sensation. [ABSTRACT FROM AUTHOR]

Given the climatic and geographical setting, Hong Kong is vulnerable to landslide risk. The poignant history of landslides catalysed the establishment of the Geotechnical Engineering Office (GEO hereafter) in 1977. Since then, a comprehensive Slope Safety System has been formulated and managed by the GEO which has effectively reduced and contained landslide risk through the implementation of multi-pronged risk management strategies. Inheriting the past success, the GEO has maintained a high vigilance of emerging landslide risk and planned ahead for the future enhancement in the System. Extensive studies for the enhancement of emergency preparedness have been conducted with a view to strengthening our capability of managing landslide risk under extreme rainfall. This paper firstly presents the key elements in the Slope Safety System in Hong Kong and then highlights the technical development work in landslide risk management, early warning, landslide emergency system etc., which have been undertaken for improving resilience of the Slope Safety System against extreme rainfall events that are becoming more frequent and intense under the effect of climate change. [ABSTRACT FROM AUTHOR]

• The proposed tropical cyclone model is completely driven by a set of environmental variables. • This model reproduces the spatial and temporal characteristics of observed tropical cyclones. • The model achieves remarkable balance between computational complexity and efficiency. • This model will provide decision-makers with valuable information regarding potential wind-induced hazards. • When future climate data are fed into this model, the impact of climate change on tropical cyclones can be evaluated. This paper presents an environment-driven tropical cyclone (TC) model for the Western North Pacific basin, which comprises a revised Poisson regression genesis model, a tailored beta-advection track model, and a fast intensity model. The TC model reproduces the temporal and spatial distributions of genesis events, the motion pattern of tracks, as well as the intensity evolutions along tracks. Risk analyses for Hong Kong and along the southeast coastline of mainland China demonstrate that this model can simulate extreme TC events with high fidelity. And the Gaussian mixture model outperforms the Frank Copula in approximating the joint distributions of the annual maximum wind speeds and the corresponding wind directions. This model is driven by a set of environmental variables including relative vorticity, relative humidity, sea surface temperature, vertical wind shear, potential intensity, sub mixed layer depth stratification, mixture layer depth and so on. This enables the model to not only reproduce historical records, but also make predictions for future TC behaviors under climate change with combination of global climate models. Besides, the computational efficiency of the TC model is comparable to traditional purely statistical models. The proposed model can also be coupled with other natural hazard models to conduct multi-hazard analysis. [ABSTRACT FROM AUTHOR]

Flooding issue and energy shortage have become the common concerns impeding the urban development under climate change scenarios. Exploiting potential hydro-energy from urban stormwater drainage system (USDS) has multiple beneficial perspectives for controlling flooding, relieving energy shortage and mitigating the greenhouse gases emission, which has not yet been systematically investigated in previous works. In this paper, a systematical analysis framework is developed to design the flooding risk control measures and to assess the feasibility and capacity of the hydro-energy development in USDS. The GCMs and HBV models, integrated within the SWMM computation platform, are adopted to simulate the hydrological and hydraulic processes during rainfall events, with the results used to manage the flooding situation and evaluate the energy generation capacity under the influences of both historical and future climate changes. The framework is then applied to a practical case in Tung Chung town of Hong Kong. The analysis result shows that, in the studied area, it is significant and worthwhile to develop the hydro-energy in USDS, which is evidenced to be beneficial to the energy generation and the flooding risk control as well as water resources management in the urban drainage system. The developed method and obtained results of this study may provide a new perspective and technical guide for effective USDS management and operation. [ABSTRACT FROM AUTHOR]

Radiative cooling coating technology is gaining increasing attention in the context of mitigating urban heat island and tackling global climate change. This paper is concerned with the development of an inorganic geopolymer-based radiative cooling coating using red mud, incorporating varying sizes of TiO 2 and hollow glass beads. The developed colored coating demonstrates its radiative cooling capability in reducing the surface temperature by harnessing the potential of red mud. The physico-chemical properties, surface morphology, and element distribution of the coating were characterized by XRD, FTIR, TG-DAT, SEM and EDS. The coating exhibited lower UV (0.0844) and visible reflectance (0.5275) but high NIR reflectance (0.7536), as well as high infrared emissivity of 0.9455, enabling a red color with a CIE value of L* = 74.56, a* = 9.55, and b* = 11.98, and a maximum temperature reduction of 7.3 °C under the climate of Hong Kong. Additionally, the skid resistance, abrasive resistance and adhesion strength of the proposed coating could meet the requirements of standards, indicating a great potential for footway applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Heavy rain events or rainstorms of various scales often occur in Hong Kong from April to September. In extremes cases, they lead to serious landslides and flash floods resulting in loss of life, and damage to property and infrastructure. With climate change, extreme rain events are projected to be more frequent and more intense in this region. A system to gauge and label the severity of rainstorms would be useful for identifying and communicating extreme conditions in warning and disaster prevention operations. In parallel, a better understanding of the characteristics of rainstorms would also be important for impact assessments and engineering design purposes. This paper formulates a practical framework to index the magnitude and severity of rainstorms in Hong Kong. An index termed as the Severity Index combining the magnitude of different rainstorm attributes is devised for quantifying the overall severity of rainstorms. This index is flexible to allow tuning for specific applications. [ABSTRACT FROM AUTHOR]

Small and micro businesses bear the brunt of climate change impacts in the climate-challenged economy. Vulnerability is embedded into the socio-economic trajectories of their primary decision-makers. Multiple vulnerabilities may arise if the decision-makers' socio-economic conditions are associated with climate-sensitive business characteristics. Previous research has provided little evidence on such linkages, thus losing insights into how different facets of vulnerability interact and evolve over time. This paper explores the interactions between elements of small business vulnerability and the socio-economic characteristics of their primary decision-makers. It draws on the results of a survey involving 116 owner-managers of small and micro businesses and in-depth interviews with a sub-sample. Study areas are three remote coastal communities in Hong Kong exposed to high floods. Results show that such interactions exist in multiple, non-linear ways. Socio-economic disadvantages (i.e. low education attainment, old age, low income, and female) are related to some aspects of small business vulnerability, while playing a role in mitigating or avoiding other aspects of it. The findings call for building frameworks that account for the multiple spheres in which vulnerabilities are engendered and their interactions, while allowing for complexities and feedback mechanisms. [ABSTRACT FROM AUTHOR]

Aim: The capacity for poleward range expansions beyond the tropics in corals hinges on ecophysiological constraints and resulting responses to climatic variability. We aimed to determine how future warming will affect coral habitat suitability at the poleward range edges of these foundational species in the Northwest Pacific. Location: Northwest Pacific. Methods: We generated models integrating thermal physiological constraints of corals adapted to extreme seasonality in Hong Kong, specifically the minimum annual temperature and the proportion of time annually spent at seasonal extremes. With these models, we projected habitat suitability for five coral species under current and future climatic conditions across the Northwest Pacific. Results: Climate model projections reveal an easing of thermal constraints on the leading‐edge of coral ecophysiological limits with an expansion of thermally suitable habitat poleward by 2°–7° in latitude depending on the coral species and model considered. We also highlight a potential divergence of present and future thermal regimes that may lead to a mismatch in suitability for corals currently inhabiting high latitude reefs. Main Conclusions: Understanding the thermal constraints on coral distributions and defining the potential range of corals under climate change is critical for adaptive management that focuses on coral conservation and ensuring ecosystem function of existing subtropical and temperate ecosystems. [ABSTRACT FROM AUTHOR]

Vertical greenery not only helps to cool the surfaces of buildings but, more importantly, it can also mitigate the Urban Heat Island effect. The growth of vertical greenery is highly dependent on ongoing maintenance, such as irrigation. Wind-driven rain serves as a natural source of irrigation for vertical greenery. Wind-driven rain simulation was conducted on a typical high-density and high-rise case in Hong Kong to first classify the wind-driven rain harvesting potential on the façade with very high, high, moderate, low, and very low levels. Then, Scenario 1 (very high potential), Scenario 2 (very high + high potential), and Scenario 3 (very high + high + moderate potential) regarding vertical greenery in locations with three levels of wind-driven rain harvesting potential were simulated in ENVI-met to assess its Urban Heat Island mitigation effect. The maximum temperature reduction on the street occurs between 12 p.m. and 3 p.m., indicating the greatest mitigation of the Urban Heat Island effect. Scenario 1, Scenario 2, and Scenario 3 achieve a maximum temperature reduction of 0.76 °C, 0.88 °C, and 1.06 °C, respectively, during this time period. [ABSTRACT FROM AUTHOR]

Maritime transport contributes to the exacerbation of global warming, which is responsible for several environmental issues. Since Hong Kong (HK) is recognized as one of the largest shipping registries in the world in terms of gross tonnage and its port is very busy, to examine the regulatory and policy measures adopted, and to discuss the need for introducing additional policy measures for controlling marine Greenhouse Gas (GHG) Emissions in HK is both necessary and important. This article accordingly investigates the current policy and regulatory measures controlling marine GHG emissions in HK, and confirms that HK implements the relevant international treaties; HK has meanwhile been working together with mainland China, particularly with cities in the Greater Bay Area (GBA), to combat air pollution. This article also highlights the main problems and issues associated with HK's existing measures, and then discusses the way forward. It concludes that the current measures in HK are far from satisfactory, and that there is an apparent need to improve them so as to more effectively control marine GHG emissions. [ABSTRACT FROM AUTHOR]

The importance of monitoring sea level in coastal zones becomes more and more obvious in the era of global climate change, because, in coastal zones, although satellite altimetry is an ideal tool in measuring sea level over open ocean, but its accuracy often decreases significantly at coast due to land contamination. Although the accuracy of waveform processing algorithms for synthetic aperture altimeters has been improved in the last decade, the computational speed is still not fast enough to meet the requirements of real-time processing, and the accuracy cannot meet the needs of nearshore areas within 1 km from the coast. To improve the efficiency and accuracy in the coastal zone, this study proposed an innovative waveform retracking scheme for the coastal zone based on a multiple optimization parabolic cylinder algorithm (MOPCA) integrated with machine learning algorithms such as recurrent neural network and Bayesian estimation. The algorithm was validated using 153-pass repeat cycle data from Sentinel-6 over Qianliyan Island and Hong Kong–Wanshan Archipelago. The computational speed of the proposed algorithm was four to five times faster than the current operational synthetic aperture radar (SAR) retracking algorithm, and its accuracy within 0–20 km from the island was comparable to the most popular SAMOSA+ algorithm, better than the official data product provided by Sentinel-6. Especially, the proposed algorithm demonstrates remarkable stability in the sense of proceeding speed. It maintains consistent performance, even when dealing with intricate wave patterns within a proximity of 1 km from the coast. The results showed that the proposed scheme greatly improved the quality of coastal altimetry waveform retracking. [ABSTRACT FROM AUTHOR]

Coastal ocean acidification is a worldwide problem associated with anthropogenic activity and climate change. In this study, a close relationship between submarine groundwater discharge (SGD) and coastal ocean acidification in Hong Kong's coastal waters is discovered. We for the first time evaluated the direct influence of SGD on seawater pH decline. Results show that SGD can contribute to up to 48% of seawater pH variation among terrestrial water input, air‐sea CO2 exchange, photosynthesis/respiration, and bay‐open water exchange in semi‐closed bays through direct input of carbonate species. Local air‐sea CO2 exchange has negligible influences on the seawater pH. In the semi‐closed bay areas, SGD and aerobic respiration are major contributors to seawater pH variation but in areas with open space, the exchange process with open waters is more important. In addition to the direct input of carbonate species (total alkalinity and dissolved inorganic carbon), SGD also influences the seawater pH via considerable nutrient loadings. The findings highlight the importance of the investigation and management of groundwater to alleviate the fast coastal ocean acidification. Plain Language Summary: Seawater becoming more acidic is a big problem in coastal areas around the world due to climate change. The main causes of this acidification are excessive nutrient release and human‐generated carbon dioxide. When groundwater flows into coastal areas, it carries chemicals from the land that can affect the pH of the seawater. In our research, we discovered that groundwater releases more dissolved inorganic carbon compounds, which lower the seawater's pH, compared to the total alkalinity that normally helps maintain a stable pH. Groundwater is a major factor in causing acidification in semi‐closed bays along the coast. We want to emphasize the importance of understanding the impact of coastal processes and managing groundwater in order to slow down the acidification of coastal waters. Key Points: Submarine groundwater discharge (SGD) strongly correlates with long‐term ocean acidification rates, unveiling their significant relationshipSGD accounts for ∼50% of seawater pH decline in semi‐closed bays, primarily through direct carbonate species inputSGD indirectly impacts seawater pH decline by influencing aerobic respiration processes, amplifying its role in pH dynamics [ABSTRACT FROM AUTHOR]

Carbon emission trading mechanism is an important market-based instrument to address global climate change. The auction ratio and price of carbon emission allowances (CEA) are cores of the carbon emission trading mechanism. What combination of CEA auction ratio and auction price is most conducive to carbon emission reduction for emission control enterprises? There are still relatively few studies conducted on this issue, and there is no clear answer from the views of theory and practice. In this paper, the AIM/Enduse model was used to analyze the changes and differences of installed power capacity, power supply, energy consumption and carbon emissions in the Guangdong-Hong Kong-Macao Great Bay Area (GBA) with different combinations of CEA auction ratios and prices. Moreover, the best pathway of energy transition was explored in the power industry of the GBA, and the best combination of CEA auction ratios and prices was identified in the GBA. The results show that: (1)The carbon emission constraint starts to work only when the auction ratio of CEA is increased to 50% and the auction price is increased to 60 CNY/ton (Scenario p 3). When the auction ratio of CEA is 100% and the auction price reaches 120 CNY/ton (Scenario p 5), a low-carbon transition of the power sector in the GBA can be achieved. (2) Under scenario p 5 , the total cost of power transition rises and then falls. And the cost of carbon in the power sector increases exponentially as the auction ratio of CEA and the auction price rise. However, the growth in the cost of power supply is relatively flat, which shows that appropriate carbon trading mechanism can improve the economic benefits of power sectors. With the increase of installed capacity of clean low-carbon energy generation and power supply, as well as the decrease of local power cost in the GBA, the proportion of outsourcing power can be appropriately reduced in the future, with an aim to reduce the external dependence of electricity to ensure the security of energy supply. In the end, it suggests that cities in the GBA should give full play to their regional advantages and establish a unified carbon emission trading market in the GBA as soon as possible. This study provides a theoretical basis for the supplementation and improvement of China's carbon emission trading mechanism. • What is the best combinations of CEA auction ratios and auction prices in the GBA? This paper gives a clear answer. • The best transition pathway of the power industry under technological progress and carbon trading policy was suggested. • With the decrease of local power cost, the proportion of outsourcing power can be appropriately reduced in the future. • Provides a theoretical basis for the supplementation and improvement of China's carbon emission trading mechanism. [ABSTRACT FROM AUTHOR]

Climate change may seriously affect the energy consumption of buildings by influencing their air conditioning loads, especially the ventilation loads which vary directly with the local weather conditions. Research on how the ventilation load responds to climate change is of great significance, especially in coastline subtropical regions like Hong Kong. This paper investigated the impacts of climate change on buildings' ventilation load and building energy use in Hong Kong with the hourly meteorological data from 1950 to 2007. Results have been well validated by the simulation of a typical local hotel building during this period. The results show that climate warming increases both sensible and latent parts of the cooling ventilation load. The latent part, which occupies ∼80% of the total ventilation load, increases at a higher rate, about twice of that of the sensible one. Furthermore, it is found that the urban heat island (UHI) effect causes a much higher growth rate of the ventilation load at night, which is about three times compared with that in the daytime. The latent part of the cooling ventilation load at night, which is found to be the most sensitive component to the climate change, plays a most significant role in the energy consumption increase. The possible measures were thus suggested to avoid negative changes of the ventilation load. Besides, reducing the UHI effect by better urban planning also significantly benefits the local buildings with a long air-conditioning operation time. [ABSTRACT FROM AUTHOR]

Abstract: Carbon footprint has become a term often used by the media in recent days. The human carbon footprint is professed to be a very serious global threat and every nation is looking at the possible options to reduce it since its consequences are alarming. A carbon footprint is a measure of the impact of human activities on earth and in particular on the environment; more specifically it relates to climate change and to the total amount of greenhouse gases produced, measured in units of carbon dioxide emitted. Effort of individuals in minimizing the carbon footprint is vital to save our planet. This article reports a study of the carbon footprint of various types of shopping bags (plastic, paper, non-woven and woven) using life cycle impact assessment (LCIA) technique in two stages. The first stage (baseline study), comprised the study of the impact of different types of shopping bags in the manufacturing phase, without considering their usage and disposal phases (cradle to gate stage). The LCIA was accomplished by the IPCC 2007 method, developed by the Inter Panel on Climate Change in SIMAPRO 7.2. The GWP (Global Warming Potential) values calculated by the IPCC 2007 method for 100 years were considered as a directive to compare the carbon footprint made by the different types of shopping bags under consideration. The next stage was the study of the carbon footprint of these bags including their usage and disposal phases (cradle to grave stage) and the results derived were compared with the results derived from the baseline study, which is the major focus of this research work. The values for usage and end-of-life phases were obtained from the survey questionnaire performed amongst different user groups of shopping bags in China, Hong Kong and India. The results show that the impact of different types of shopping bags in terms of their carbon footprint potential is very high if no usage and disposal options were provided. When the carbon footprint values from different disposal options were compared, the carbon footprint values were lower in the case where a higher percentage of reuse is preferred to recycling and disposing to landfill. The results indicate that a higher percentage of reuse could significantly scale down the carbon footprint. Once the shopping bags reached the point where they can no longer be reused, they must be forwarded to recycling options, rather than being disposed to landfill. At this juncture, consumer’s perceptions and behaviours in connection with the respective government’s policies in promoting & facilitating recycling systems could be critical in reducing the carbon footprint of various shopping bags. [Copyright &y& Elsevier]

This study examines attitudes to tourism and climate change among residents of Hong Kong and evaluates their willingness to voluntarily modify travel behaviours to reduce environmental impacts. Previous studies on environmental behavioural change identified a significant gap between awareness and action, with some studies even suggesting that the most aware individuals are unlikely to change their behaviours. Similar findings were noted in this study. Cluster analysis identified four cohorts of tourists, ranging from the regular international tourist to the least travel active. The regular international tourist group was most aware of global warming and climate change, but least willing to alter its travel behaviour. By contrast, less travel active tourists seem most willing to travel less. The paper concludes that government intervention may be required to create meaningful behavioural change in travel patterns. [ABSTRACT FROM AUTHOR]

Summary: Tall buildings located in Hong Kong can suffer great damage caused by typhoon hazards throughout their lifetimes. In addition, the effect of wind hazards may be exacerbated due to increases in the typhoon intensity and frequency caused by the climate change effect. Therefore, developing a framework to evaluate and quantify the damage caused by wind hazards on tall buildings from the economic perspective is critical for engineers and building owners in designing a cost‐effective tall building. In this study, an economic damage indicator, life‐cycle cost, is measured by using a probabilistic method called life‐cycle cost analysis (LCCA). Moreover, the building sector is one of the biggest contributors to greenhouse gas (GHG) emissions, and the environmental impact that may be generated in intervention activities after wind‐induced damage occurs is analyzed. An environmental impact indicator, embodied carbon emission, is quantified by employing another probabilistic method called life‐cycle assessment (LCA). Therefore, an integrated methodology combining the LCCA and LCA is proposed to evaluate potential damage costs and environmental impact caused by typhoon hazards on tall buildings. [ABSTRACT FROM AUTHOR]

The growing interconnectedness of urban infrastructure networks presents challenges to their ability to handle unforeseen disruptions, particularly in the context of extreme weather events resulting from climate change. Understanding the resilience of interconnected infrastructure systems is imperative to effectively manage such disruptions. This study investigates the role of interconnectedness in enhancing the resilience of public transportation systems in Hong Kong, a city heavily reliant on public transit. Our results demonstrate that interconnected transportation systems improve resilience by reducing topological vulnerabilities, increasing attack tolerance, and enhancing post-disruption interoperability. Findings also identify the potential to integrate vulnerable systems for greater robustness and highlight the marginal benefits of enhancing intermodal transfer. Strengthening interconnectedness among modes of urban public transit fosters a safe-to-fail system, presenting a distinct resilience-by-design approach. This complements conventional resilience-by-intervention approaches that focus on improving individual systems or introducing entirely new systems. The growing interconnectedness of networked infrastructures has a complex impact on resilience in urban environments. Xu and Chopra quantify these effects using network resilience analysis and highlight the benefits of topological interconnectedness within multimodal public transportation systems. [ABSTRACT FROM AUTHOR]

An extreme rainstorm can cause thousands of landslides and kill hundreds of people. In the changing climate, fatal rainstorms become more frequent and intense. The current landslide emergency management evaluates hazard intensities but lacks key information on likely consequences. This study presents a novel prompt quantitative risk assessment method for rain-induced landslides. The proposed method automatically generates a one-page risk assessment report within minutes to support effective risk communication, resource allocation, and emergency response. The propagation of uncertainties is quantified in a scientific probabilistic framework. The proposed method is tested using 83 major rainstorms during 1995–2016 in Hong Kong. The method accurately predicts the number of affected buildings and the number of potential fatalities and identifies rainstorms that can trigger fatal landslides. The proposed method contributes to the advancement of landslide emergency management from hazard-informed to risk-informed, which will significantly enhance societal resilience and facilitate climate change adaptation. [ABSTRACT FROM AUTHOR]

The spatiotemporal distributions and physical–optical properties of aerosols are of great scientific significance for the study of climate change and atmospheric environment. What are the characteristics of aerosols in constant high humidity? Continuous wet weather (CWW) is a special weather phenomenon that occurs frequently during the late winter and early spring in South China. In this study, the CALIPSO satellite data and the ERA5 and MERRA-2 reanalysis data are used to analyze the aerosol optical properties of a total of 68 CWW processes from 2012 to 2021 in the Guangdong–Hong Kong–Macau Greater Bay Area (GBA). We attempt to explore the variations in meteorological conditions and physical–optical properties of aerosols during the before-stage, wet-stage, and after-stage under different humidity levels. The results show that the prevailing wind direction is northeasterly and that the temperature and humidity are lower under the influence of cold high pressure in the before-stage. Moreover, the high aerosol optical depth (AOD) mainly results from regional transport. During the wet-stage, clean ocean airflow causes AOD to remain at a low level, whereas temperature and humidity increase significantly. The wet-stage ends with coldness when it is controlled by cold high pressure again. The atmospheric circulation in the after-stage is similar to that in the before-stage. However, a remarkable feature is that there is a temperature and humidity inversion layer, which results in a significant increase in AOD. This study reveals the physical–optical properties of aerosols during the three stages and the influence mechanism of meteorological factors on aerosols, which can provide a scientific basis for the study of CWW in the future. [ABSTRACT FROM AUTHOR]

Urban greening has rapidly emerged as a key urban climate change adaptation strategy. Urban greening is thought to confer manifold socio-ecological benefits upon residents in towns and cities. Yet proponents of urban greening have seldom considered how people’s support for greening policies may be shaped by weather and climate. This paper reports the results of exploratory research examining public expectations of adverse weather changes and people’s attitudes toward the functional benefits of urban trees and green space. Results of a questionnaire survey of 800 residents of Hong Kong indicate a positive relationship. Respondents tended to rate functional benefits as more important if they anticipated adverse weather changes in the near future, namely, rising temperatures, more tropical cyclones and prolonged rain. This subjective weather effect is more salient when these weather changes are perceived as a threat to one’s daily life. We found urban greenery is assigned a higher value by individuals concerned about exposure and vulnerability to climatic stressors. Affinity for greening appears to be related to how weather and climatic variability is perceived. This observation is informed by a broader geographic perspective, which construes weather and climate as part of the spatial environment in which urban nature is apprehended and comprehended. An explanation for our findings is that increasingly volatile weather can potentially reshape urban residents’ interactions with nature, based on perceived relief and/or protection from climate-related threats. [ABSTRACT FROM AUTHOR]

In Hong Kong, rain-induced shallow slope failures are recognized as one of the most catastrophic hazards due to Hong Kong's hilly terrain and frequent heavy storms. Due to climate changes, extreme storms are expected to be more frequent and intense in the future. The prediction of shallow slope failures under extreme storms is therefore essential. This study aims at simulating likely shallow slope failures on western Hong Kong Island under extreme storms. The terrain and slopes are discretized into a grid of cells on a geographical information system. Then, the pore-water pressure regime in the ground is analyzed through an infiltration analysis. Next, the slope stability and debris movement are assessed using a well-established model, which has been validated with landslides triggered in two past storm events. Finally, the shallow slope failures under three extreme storms at 44, 65, and 85% of the probable maximum precipitation are simulated. Under such extreme storms, more than 300 major slope failures may occur, occupying 0.5-1.7% of the natural terrain area. Some of the simulated movement traces and deposition locations are close to the urban area, calling for new strategies for landslide risk management. [ABSTRACT FROM AUTHOR]

• A multi-model and multi-method ensemble approach for wind resource projection is proposed. • Future wind potential in Hong Kong is assessed for the first time. • Robustness of the climate change signal is evaluated. • An increase in wind power density during summer (+23.7 %) and a decrease during autumn (–15.1 %) in 2081–2100 are projected for SSP5-8.5. Harvesting renewable wind energy is among the most cost-efficient means of reducing carbon emissions and achieving carbon neutrality. However, wind resource is susceptible to climate change impacts since the global temperature increase will reshape atmospheric circulation patterns. To facilitate the evaluation of fine-scale wind energy potential under climate variability, this paper proposes and validates a multi-model and multi-method ensemble wind resource projection approach. Then this approach is utilized to investigate the future variation of wind resources in Hong Kong based on the combined use of global climate models from Coupled Model Intercomparison Project Phase 6 and long-term observations from meteorological stations. It is found that there is a significant increase in future wind resources during summer, while a remarkable decline is projected during autumn. Nevertheless, the variations of wind resources in winter and spring are relatively insignificant. The outcomes of this study are expected to offer a framework for fine-scale wind resource assessment under climate change, and facilitate the economic and risk assessments of future wind farm projects. [ABSTRACT FROM AUTHOR]

The paper studies the horizontal global, direct-beam and sky-diffuse solar irradiance data measured in Hong Kong from 2008 to 2013. A machine learning algorithm was employed to predict the horizontal sky-diffuse irradiance and conduct sensitivity analysis for the meteorological variables. Apart from the clearness index (horizontal global/extra atmospheric solar irradiance), we found that predictors including solar altitude, air temperature, cloud cover and visibility are also important in predicting the diffuse component. The mean absolute error ( MAE ) of the logistic regression using the aforementioned predictors was less than 21.5 W/m 2 and 30 W/m 2 for Hong Kong and Denver, USA, respectively. With the systematic recording of the five variables for more than 35 years, the proposed model would be appropriate to estimate of long-term diffuse solar radiation, study climate change and develope typical meteorological year in Hong Kong and places with similar climates. [ABSTRACT FROM AUTHOR]

Urban heat islands (UHIs), usually defined as temperature differences between urban areas and their surrounding rural areas, are one of the most significant anthropogenic modifications to the Earth's climate. This study applies the extreme value theory to model and detect trends in extreme UHI events in Hong Kong, which have rarely been documented. Extreme UHI events are defined as UHIs with intensity higher than a specific threshold, 4.8 for summer and 7.8 °C for winter. Statistical modeling based on extreme value theory is found to permit realistic modeling of these extreme events. Trends of extreme UHI intensity, frequency, and duration are introduced through changes in parameters of generalized Pareto, Poisson, and geometric distributions, respectively. During the 27-year study period, none of the quantities in winter analyzed in this study increased significantly. The annual mean summertime daily maximum UHI intensities, which are samples from a Gaussian distribution, show an increasing but nonsignificant linear trend. However, the intensity of extreme UHI events in summer is increasing significantly, which implies that the risk of mortality and heat-related diseases due to heat stress at night (when the daily maximum UHI occurs) in summer is also increasing. The warming climate has threatened and will continue to threaten inhabitants of this subtropical high-density city. Strategies for adaptation to and mitigation of climate change, such as adding greenery and planning a city with good natural ventilation, are needed. [ABSTRACT FROM AUTHOR]

This work offers a new perspective on the predictions of the wind fields of typhoons in Hong Kong, which takes into consideration the effects of climate change. An integrated model combining (1) the Monte-Carlo simulation methodology, (2) four future climate change scenarios gathered from the shared socioeconomic pathways (SSPs), and (3) a refined typhoon wind field model combined with the probabilistic models of typhoon key parameters has been developed and validated herein, by employing the four climate scenarios reported in Phase 6 of the Coupled Model Intercomparison Project. The direct consequence is that the probability distributions of the six key parameters of a typhoon's wind fields—translational velocity, approach angle, central pressure deficit, the radius of maximum wind, the distance of closest approach, and annual occurrence rate—should be modified according to the increase in sea surface temperatures. In this study, the key parameters are drawn from the modified distributions and input into the refined wind field models to predict the typhoon wind field in the future with preset climate change scenarios. Via the Monte-Carlo simulations of 10,000 virtual typhoons, the probabilistic characteristics of the typhoon wind speeds and directions are predicted. More specifically, the predictions at the Waglan Island in Hong Kong are compared with the corresponding statistics calculated from the current meteorology database, and the comparisons suggest that the rise of SST will result in slight increases in typhoon wind speeds. In addition, the typhoon wind direction, in general, drifts counterclockwise due to the increase in SSTs. [ABSTRACT FROM AUTHOR]

Under the Kyoto Protocol's Clean Development Mechanism (CDM), countries worldwide co-operate on encountering climate change by emissions trading, which enables a win–win situation by effectively “regenerating” a cleaner environment in developing countries, whilst efforts in developed countries may still not meet their committed targets of carbon reduction. According to the CDM rules, energy efficiency improvement projects in the building sector are valid for emissions trading. Although the potential saving of energy is significant, there is only a limited number of building projects being registered as CDM projects. This paper explores the applicability of CDM in the building sector by reviewing the implementation of CDM and its advantages and disadvantages. Hong Kong was selected for an in-depth study due to its eligibility for CDM and yet non-starter status. According to a questionnaire survey supplemented by interviews with the stakeholders in this study, major hindrances such as the lack of financial incentive, inadequate knowledge about emissions trading and insufficient governmental support were found in potential CDM projects in the building sector. It is recommended that an inter-city emissions trading market covering mainland China and Hong Kong, and suitable emission reduction targets should be established and led by the government at the initial stage. By setting up an emission exchange centre, local emissions trading activities could be facilitated and job opportunities could be created. In addition to conducting emissions trading, Hong Kong may also contribute to emissions trading in the region by making use of its highly skilled professional services and efficient business environment. This study paves the way for a densely built city such as Hong Kong to benefit environmentally and economically from a cleaner region in its vicinity. [ABSTRACT FROM AUTHOR]

Possible thermodynamic effects of global warming on the landfalling typhoons that affect South China and their associated storm surges over Pearl River Delta region are investigated, using the Weather Research and Forecasting (WRF) Model and the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model based on the pseudo–global warming (PGW) technique. Twenty intense historical TCs that brought extreme storm surges to Hong Kong since the 1960s are selected and replicated by the 3-km WRF Model, with the outputs to drive the SLOSH model in storm surge simulation. The tracks, intensities, storm structure, and induced storm surges are well simulated. The PGW technique is then used to build a warmer background climate for the 20 selected TCs in the period of 2075–99 under the RCP8.5 scenario. To obtain a better adjusted warming environment, a pre-PGW adjustment method is developed. Comparing the same TCs in PGW experiments and historical runs, the TC lifetime peak (landfall) intensity can be intensified by about 9% 6 8% (12% 6 13%), with a ∼3% increase of TC peak intensity per degree of SST warming being inferred. The TCs are projected to be more compact, with the radius of maximum wind (RMW) reduced by ∼7% 6 10%. TC precipitation is also expected to increase, with the extreme precipitation within the eyewall strengthened by 22% 6 12%. All the above characters have passed the Student’s t test at 0.05 significance level. Finally, the projected induced storm surges near the Hong Kong waters are not significantly tested, although a weak storm surge height increase tendency is revealed. [ABSTRACT FROM AUTHOR]

Improving the energy performance of existing building refurbishment has been identified as one of the key measures to reduce greenhouse gases (GHGs) emissions and combat climate change. However, little has been done to uncover how human behaviours would affect the selection of refurbishment solutions selection. The problem is particularly obvious for high-rise residential buildings as they are owned and/or occupied by different peoples with idiosyncratic behaviour and preference. In this research, 46 potential methods commonly used for major sustainable building refurbishment in high-rise residential buildings located in cities with sub-tropical climate like Hong Kong were identified through literature review. These sustainable building refurbishment methods are classified under five groups namely energy user pattern, domestic, high-rise building, climate feature and other building characteristics. A questionnaire survey was conducted to examine the feasibility of the identified refurbishment methods based on the perception of owners and occupants. The results show that those methods classified under building services category such as lighting, appliance, ventilation and lift received greater support from owners and occupants. It is interesting to note that owners and occupants did not favour those sustainable refurbishment options which are related to the building envelop when it comes to major building refurbishment. As for the renewable energy refurbishment methods, their acceptability was moderate indicating that there is huge potential for being incorporated into the major building refurbishment. This paper should help improve our understanding on what factors contribute to the satisfaction of owners and occupants of high-rise residential building in a major sustainable refurbishment scheme. [ABSTRACT FROM AUTHOR]

Here we used Empirical Mode Decomposition (EMD) method to study seasonal variability and nonlinear trend of corrected AERONET Aerosol Optical Depth (AOD/Hi) and corrected PM mass concentrations (PM× f(RH)) in Hong Kong during 2005-2011. AOD/Hi is highly correlated with PM× f(RH) in semi-annual and annual time scales (with correlation coefficient 0.67 for semi-annual and 0.79 for annual components, 95% confidence interval). On the semi-annual scale, both AOD/Hi and PM× f(RH) can capture the two maxima in March and October, respectively, with much stronger amplitude in March probably due to the long-range transport of dust storm. On the annual cycle, the AOD/Hi and PM× f(RH), which are negatively correlated with the precipitation and solar radiation, vary coherently with the maxima in February. This annual peak occurs about one month earlier than the first peak of the semi-annual variability in March, but with only half amplitude. During 2005-2011, both AOD/Hi and PM× f(RH) exhibit the pronounced decreasing trend with the mean rate of 14 μg m per year for PM× f(RH), which reflects the significant effects of the air pollution control policy in Hong Kong during the past decade. The nonlinear trend analysis indicates that the decreasing of PM× f(RH) is slower than that of AOD/Hi when the AOD/Hi is less than 0.44 but becomes faster when the AOD/Hi exceeds 0.44. These results illustrate that the AERONET AOD can be used quantitatively to estimate local air-quality variability on the semi-annual, annual, and long-term trend time scales. [ABSTRACT FROM AUTHOR]

Urban resilience is an attractive concept among academies and governments with the increasing severity of climate change and relevant disasters in cities. Few studies have been conducted to compare the key elements of attentions for enhancing urban resilience among Asian cities, although resilience is context-dependent. This study aims to compare the key elements of attentions for enhancing urban resilience among Singapore, Hong Kong and Hangzhou. A comprehensive literature review and expert interview validation were used to solicit the preliminary elements of attentions for enhancing urban resilience. Planners and researchers in the field of urban planning were surveyed to assess the significance level of the preliminary elements in the three case cities, as professional knowledge is required in the survey. Statistics were used to identify the key elements of attentions in the three case cities. Results demonstrate that the three cities have various elements of attentions for enhancing urban resilience despite sharing many similarities, which also demonstrate the guidance limitation of the general urban resilience framework. It also provides a reference for other international comparisons. [ABSTRACT FROM AUTHOR]

Urban heat island (UHI) and cool island (UCI) effects are well‐known and prevalent in cities worldwide. An increasing trend of extreme heat events has been observed over the last few decades and is expected to continue in the foreseeable future. In this study, warm periods (May to September) of 2000–2018 were examined to acquire a comprehensive understanding of the UHI and UCI characteristics for the case study of Hong Kong, China. Twenty‐two weather stations in Hong Kong were classified into four categories, namely urban, urban oasis, suburban, and rural, with reference to the local climate zone (LCZ) scheme, to analyze UHI and UCI phenomena during extreme heat and non‐extreme heat situations. One representative type of extreme heat events was considered in this study: three consecutive hot nights with two very hot days in between (2D3N). Results show that both the UHI and UCI effects are exacerbated during extreme heat events. Using the concept of the UHI degree hours (UHIdh) and UCI degree hours (UCIdh), their spatial patterns in Hong Kong during extreme heat and non‐extreme heat situations were mapped based on multiple linear regression models. It is found that the predictor variable – windward/leeward index is a significant influential factor of both UHIdh and UCIdh during extreme heat events. The resulting UHIdh and UCIdh maps not only enhance our understanding on the spatial pattern and characteristics of the UHI and UCI during extreme heat events, but could also serve as a useful reference in climate change adaptation, heat‐health risk detection, cooling‐energy estimation and policy making. [ABSTRACT FROM AUTHOR]

Abstract: In subtropical Hong Kong, buildings consume the most of the electricity use. Computer simulation technique is a useful tool for predicting building thermal and energy performance. Simulation computer programs require weather data input to drive the mathematical models within the simulation tools for comparative studies and annual energy estimation. Typical weather year data representing the long-term climatic conditions are often used. Recently, there has been an increasing interest in incorporating daylight in the architectural and building designs to reduce building energy consumption. However, daylight parameters are not always available. In 2003, the International Commission on Illumination (CIE) adopted a range of 15 standard skies covering probably the whole spectrum of the usual skies in the world. Once the skies have been identified, the basic solar irradiance and daylight illuminance at various inclined planes can be obtained. This paper presents the work on the development and evaluation of two typical weather datasets, namely Typical Meteorological Year (TMY) and Test Reference Year (TRY). Measured hourly weather data for the 30-year period from 1979 to 2008 were analysed. Building energy simulations were conducted to evaluate the two weather datasets. Daylight parameters were derived using luminous efficacy approach and the sky conditions were categorized based on common climatic variables. [Copyright &y& Elsevier]

Abstract: The concern on climate change leads to growing demand for minimization of energy use. As building is one of the largest energy consuming sectors, it is essential to study the impact of climate change on building energy performance. In this regard, building energy simulation software is a useful tool. A set of appropriate typical weather files is one of the key factors towards successful building energy simulation. This paper reports the work of developing a set of weather data files for subtropical Hong Kong, taking into the effect of future climate change. Projected monthly mean climate changes from a selected General Circulation Model for three future periods under two emission scenarios were integrated into an existing typical meteorological year weather file by a morphing method. Through this work, six sets of future weather files for subtropical Hong Kong were produced. A typical office building and a residential flat were modeled using building simulation program EnergyPlus. Hourly building energy simulations were carried out. The simulated results indicate that there will be substantial increase in A/C energy consumption under the impact of future climate change, ranging from 2.6% to 14.3% and from 3.7% to 24% for office building and residential flat, respectively. [Copyright &y& Elsevier]

The historical and political context of the change of sovereignty in 1997 has determined Hong Kong's unique response to the global challenge of climate change. As a Special Administrative Region of the People's Republic of China under the principle of "One Country Two Systems," Hong Kong not only has the obligation to mitigate Greenhouse Gas (GHG) emissions in response to China's evolving climate change policies from Rio to Copenhagen, but also enjoys special privileges and potential advantages as a result of enhanced cross-border cooperation with Mainland China in areas of Clean Development Mechanism (CDM) projects, carbon trade and clean energy supply. Both the international climate change regime and national policies have created great opportunities for Hong Kong to take the lead in the transformation to low-carbon society and make a substantial contribution to achieving the national target of 40-45 percent cut in carbon intensity by 2020 compared to the 2005 level. Where there is a will there is a way. What Hong Kong needs is the political will to do the right thing. [ABSTRACT FROM AUTHOR]

This article represents a first attempt to pull together relevant materials with the aim of providing a broad-brush view of how climate change may affect Greater Pearl River Delta (GPRD) region (Hong Kong, Macau and the Pearl River Delta). Among the various consequences of climate change, rising sea levels are a matter of great concern for the GPRD region, which is made vulnerable both by its physical geography (the southern part of the delta lies between - 0.3m to 0.4m relative to mean sea level (MSL)) and its urban development. More in-depth research and modeling remain to be done so that the authorities, business and civil society can better understand climate impacts on the region, but this article shows that climate change could have a big impact on the regional economy, which represents nearly 10% of China's GNP. The paper concludes with a discussion of the measures that government and businesses will need to consider in order to adapt to these future conditions. [ABSTRACT FROM AUTHOR]

Abstract: Accurate prediction of building energy performance requires precise information of the local climate. Typical weather year files like test reference year (TRY) and typical meteorological year (TMY) are commonly used in building simulation. They are also essential for numerical analysis of the sustainable and renewable energy systems. The weather year file of one city is often employed by the nearby cities for such purposes. In this paper, the developments of customized weather year formulation are reviewed. The key issues are discussed making reference to two neighboring cities, Hong Kong and Macau, using their weather data records over a century, and the typical weather year files developed. The findings support the preference of TMY over TRY. It is also suggested that the TMY selection process should include the most recent meteorological observations, and should be periodically reviewed to well reflect the long-term climate change. [Copyright &y& Elsevier]

Climate change issues and building energy use implications in subtropical Hong Kong were examined. A total of 40 years (1961–2000) of measured hourly temperature data were gathered and analysed. Three different parameters were examined, namely mean temperature, cumulative frequency of occurrence and cooling degree days (CDD). It was found that there was an underlying trend of temperature rise in recent years. Such temperature increase tended to occur more frequently during the winter period and mid-season than the summer months. The slight increase in CDD during the last 20 years suggested that cooling requirements and, hence, energy use for air conditioning might be affected if the trend persisted. The frequency of occurrence analysis, however, revealed no significant changes in the outdoor design conditions, and peak building cooling loads were expected to remain unchanged. This paper presents the work and discusses the energy use implications. [Copyright &y& Elsevier]

• Economic drivers and barriers were identified to be most significant for ZCB in HK. • User behavior changes can have a major impact on ZCB delivery in HK. • Four strategy areas most address ZCB complexities and dynamics in high-density cities. • ZCB requires micro-level measures, meso -level initiatives and macro-level visions. • A novel multi-level framework of strategies is derived for high-rise high-density ZCB. The zero carbon building (ZCB) approach has been adopted in many cities and regions as an important government strategy for addressing climate change, achieving a low carbon economy, and uplifting the quality of people's life. However, there is yet a lack of uptake of ZCB in high-rise high-density contexts, and mystery exists about its feasibility and societal acceptance. This paper aims to demystify ZCB development in high-rise high-density cities by identifying and examining the drivers, barriers and strategies within Hong Kong as a typical case. Based on the systems theory that addresses ZCBs as complex systems, the research was conducted through a questionnaire survey with 219 effective responses from and six follow-up focus group meetings with industry stakeholders. Key drivers and barriers were systematically identified, covering economic, legislative, cultural, supply chain, geographical, and skill and knowledge aspects. Specifically, economic drivers and barriers were found most significant. A novel multi-level framework of strategies was further derived, integrating micro-level measures, meso -level initiatives and macro-level visions for achieving ZCBs in high-rise high-density cities. The framework contributes a new perspective to examine ZCB drivers and barriers, and lays the foundation for a strategic decision-making tool to support ZCB developments. [ABSTRACT FROM AUTHOR]

• 40-years datasets are used to train and validate different data-driven models. • The performance of different popular data-driven methods is compared. • The proposed GBDT method outperforms other data-driven methods. • Future electricity demand in Hong Kong is predicted by the GBDT model. • Future climatic and socio-economic uncertainties are considered in the model. Data-driven methods, such as artificial neural networks (ANNs), support vector regression (SVM), Gaussian process regression (GPR), multiple linear regression (MLR), decision trees (DTs), and gradient boosting decision trees (GBDTs), are the most popular and advanced methods for energy demand prediction. However, these methods have not been cross compared to analyze their performances for long-term energy demand predictions. Therefore, this paper aims to identify the best method among these data-driven methods for quantifying the impacts of climatic and socioeconomic changes on future long-term monthly electricity demand in Hong Kong. First, historical 40-year climatic, socioeconomic, and electricity consumption data are used to train and validate these models. Second, different representation concentration pathway (RCP) scenarios and three percentiles of 24 global circulation model outputs are adopted as future climatic changes, while five shared socioeconomic pathways are considered for future socioeconomic uncertainties. The results show that the GBDT method provides the best accuracy, generalization ability, and time-series stability, while ANN method exhibits the lowest accuracy and lower generalization ability. The monthly electricity demands in Hong Kong under the RCP8.5–2090 s scenario are predicted to increase by up to 89.40 % and 54.34 % in the residential and commercial sectors, respectively, when compared with 2018 levels. [ABSTRACT FROM AUTHOR]

The Guangdong-Hong Kong-Macao Greater Bay Area (GBA) is the world's largest bay area in terms of land area and population, which has been increasingly suffering from weather and climate extremes under global warming. It is thus desired to produce reliable high-resolution climate information at a regional scale in order to enhance resilience to climate change over the GBA. For the first time, this study develops the multi-decadal nested-grid climate projections at a convection-permitting scale for the GBA, and assesses the abilities of the Weather Research and Forecasting (WRF) model with 36-, 12- and 4 km resolutions in representing precipitation, temperature and their extremes. Our findings indicate the added value of the convection-permitting WRF model for simulating the spring and summertime precipitation as well as extreme heavy rainfall events with daily amounts larger than 30 mm over the GBA. Increasing the spatial resolution of the WRF model does not necessarily lead to a significant improvement on temperature simulations. In addition, our findings reveal that the GBA is expected to have an increasing number of heavy and extreme heavy rainfall events by the end of the twenty-first century. Moreover, the GBA is projected to have a large temperature change across different seasons, and an enhanced warming will appear in autumn. The GBA is also expected to have more summer days with longer durations, thereby leading to an increasing risk of heatwaves and heat stress. [ABSTRACT FROM AUTHOR]

Despite the importance of overcoming the persistent delay in climate action, almost no research has investigated the psychological underpinnings of climate change denial in Asian countries. Addressing this research gap, our study compares results obtained in Hong Kong with those of samples from New Zealand and Sweden regarding correlations of climate change denial with acceptance of dominance between social groups (Social Dominance Orientation), acceptance of two additional forms of group‐based dominance (humans over nature, and humans over animals), and empathic concern. Results showed that only acceptance of human dominance over nature and animals predicted climate change denial in Hong Kong. In New Zealand and Sweden, however, the results resembled those found in previous research: The strongest predictor was Social Dominance Orientation, followed by acceptance of human dominance over nature. Low empathic concern predicted climate change denial only in Sweden. Results in Hong Kong differ from previous findings and indicate that climate change denial in this East Asian society is motivated more by hierarchical attitudes related to nature than social groups. We discuss possible reasons for these distinct findings and conclude that there is a need for cross‐cultural research to further investigate the psychological and culture‐specific motivations to dismiss climate change. [ABSTRACT FROM AUTHOR]

• In-situ monitoring allows for a more reliable estimation of envelope performance of residential buildings. • Policy differences are one of the main causes for the variation in building envelope performance across regions. • Potential global warming impacts ought to be considered when pondering on the future direction of envelope development of residential buildings. • Interactive policy framework underscores the necessity of devising more comprehensive public policies pertaining to energy saving. Climatic conditions can exert significant impacts on energy demand of residential buildings. Therefore, case-based evidence is necessary for aiding local policy making on building energy performance. By designing and carrying out in-situ monitoring campaigns respectively in Cambridge, Hong Kong and Shanghai, we present in this paper a cross-regional analysis of actual building envelope performance in these three climatic regions that operate under different energy efficiency policies. Compared with conventional tabulated data, information gleaned from the method of in-situ monitoring shows lower uncertainty and higher precision, especially when the wall has good thermal properties. By comparing practices in different regions and with accurate post-occupancy thermal data, the analytical results further show that the effectiveness of building-related policies on energy performance varies across regions. This is one of the pioneering studies that make interactive policy recommendations based on the evidence obtained from cross-regional, in-situ monitoring campaigns. [ABSTRACT FROM AUTHOR]