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This study aims to analyze city networks as they face the challenges of global warming. It seeks to introduce the notion of “governance from the middle” as an alternative to traditional intergovernmental policy. This is developed by focusing on the particular experiences of the C40 Cities Leadership Group and discussing its prospects and risks.

CCI works with a number of commercial banks, institutional investors, international financial institutions and other capital providers to design financing programmes and source capital.

The C40 Group illustrates some fundamental traits of city networks with a hybrid governance structure, combining traditional public institutional structures with market‐based arrangements, organizationally and qualitatively governing from the middle. Critical factors in this dynamic are the use of an external implementing body, providing new organizational opportunities for the network, and the prominence given to an integrated procurement process, which develops incentive structures for action and effectively connects actors at various levels of society. The latter emphasis on market‐incentives as a template for action is an innovative governance feature but not the panacea many want. The complex nature of the governance arrangement itself, the structural asymmetries among its members, and the diversified set of issues the network intends to address are all factors that remain to be researched.

The study provides new perspectives on the conceptual discussions about governance by introducing the notion of “governance from the middle”. These allow us in turn to continue research about the role of market‐arrangements in linking global and local ambitions. This could have a decisive policy impact on climate governance in general.

Climate change presents potential increased threats to the comfort and health of urban populations as a result of higher summer temperatures. This paper reviews recent research on the climate change adaptation potential of urban environments and focuses on a major conurbation, London. Recent work relating to the impact of exposure to heat on population health is also noted. Data obtained from a pilot monitoring study carried out in a subset of 36 dwellings (from a total of 110 dwellings in the overall study) across London during the summer of 2009 is then discussed. Preliminary results illustrate the need to quantify the net impacts of individual building characteristics and the location of each dwelling within the London heat island. During a hot period, more than 40% of the monitored bedrooms failed the recommended overheating criteria during the night time. There was some indication of purpose built flats being more prone to overheating. The potential use of such data as the basis of a heat-related health risk epidemiological model for London is discussed. Such a tool would help health policy makers to target the most vulnerable building types and areas.

Morocco is facing climate change, as shown by national studies conducted to date. The purpose of our research work is, on one hand, to develop an experimental protocol; simulating the Moroccan climate, through exposing concretes to accelerated aging in different cycles of temperature variation (+5 to +40 C°) and humidity (60–98% RH) and on another hand, to determine the effect of exposure to temperature and humidity variation cycles on the durability indicators (of concrete [with and without thermal cure]).

For this purpose, three classes of concrete were studied (C35, C40 and C55). Each class of concrete was considered first with no addition of silica fume (SF) and then with a 10% addition of SF. The concrete samples underwent three types of conditioning before performing the tests. The control concretes (Ct) were demoulated after 24 h and stored under stable temperature and humidity conditions (20 ± 2 °C and 80% ± 5 RH). Treated concretes (CV) demouled after 24 h and exposed to 300 cycles of 12 h of temperature and moisture variation in a climate chamber. And finally, concretes that have undergone a heat cure (CTV) for 5 h at 90 °C, were then removed from the mold and exposed to temperature and moisture variations cycles identical to treated concrete (CV).

The results obtained show that aging accelerated by temperature change, and humidity improves durability indicators compared to Ct. Concretes that have undergone a thermal cure, followed by accelerated aging, show an improvement in durability indicators between 50 and 200 cycles, but the performance of concrete decreases after 200 exposure cycles. The addition of SF plays a beneficial role in the durability of concrete in the three exposure environments.

The originality of the work is, to develop an experimental protocol, simulating the Moroccan climate, through exposing concretes to accelerated aging in different cycles of temperature variation (+5 to +40 C°) and humidity (60–98% RH) and on another hand, to determine the effect of exposure to temperature and humidity variation cycles on the durability indicators of conventional concrete (with and without thermal cure).

The purpose of this paper is to compare the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments and ultimately to provide basis and recommendations for the durability design of reinforced concrete (RC) structures.

Slag concrete specimens mixed with four kinds of rust inhibitors and coated with four kinds of surface strengthening materials were corroded by seawater exposure for 365 days, and the key parameters of chloride ion diffusion were obtained by testing. Then a new service life prediction model, based on the modified model for chloride ion diffusion and reliability theory, was applied to analyze the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments.

Rust inhibitors and surface strengthening materials can effectively extend the service life of RC structures through different effects on chloride ion diffusion behavior. The effects of rust inhibitors and surface strengthening materials on the service life extension of RC structures adhered to the following trend: silane material > cement-based permeable crystalline waterproof material > hydrophobic plug compound > spray polyurea elastomer > water-based permeable crystalline waterproof material > calcium nitrite > preservative > amino-alcohol composite.

Using a new method for predicting the service life of RC structures, the attenuation law of the service life of RC structures under the action of rust inhibitors and surface strengthening materials in tropical marine environments is obtained.

Cities are crucial to reducing greenhouse gas (GHG) emissions. This paper aims to explore the quality of GHG disclosures by cities via the Carbon Disclosure Project (CDP) and compares them with the expectations of users.

The expectation gap framework is used to examine the GHG disclosure quality of 42 cities. User expectations are determined via a literature review and CDP documentation. City disclosures are reviewed using content analysis.

GHG information at the city level is outdated, incomplete, inconsistent, inaccurate and incomparable and, therefore, to meet user expectations, improvement is needed.

The findings have implications for policymakers, stakeholders and managers. Guidelines are required for better disclosure of GHG information relating to cities, and stakeholders need to develop better skills to understand emissions information. Managers have a responsibility to measure, disclose and mitigate GHG emissions to meet the expectations of stakeholders.

Prior studies focus on GHG disclosures via the CDP by corporations. This is the first accounting study to examine GHG disclosures by cities via the CDP. The expectation gap framework is a novel approach to sustainability disclosure research.

The purpose of this empirical case study is to study and explain the role of public leadership in the expansion of municipal climate action in Canada.

In 2017 and 2018, the authors conducted13 semi-directed interviews with municipal staff and elected officials from three municipalities, a documentary analysis of primary and secondary sources. Interviews and documentation collected were also coded using the software NVIVO 12. The authors compared three municipal case studies: the City of Toronto (Ontario), the City of Guelph (Ontario), and the Town of Bridgewater (Nova Scotia).

The authors found that leadership is a prominent factor explaining the expansion of municipal climate action in Canada. Municipal climate action is initiated and championed by an individual, elected officials or municipal staff, who lead and engage in the development of policy instruments to mitigate and/or adapt to climate change. These leaders facilitate the formulation and implementation of instruments, encourage a paradigm shift within the municipality, overcome structural and behavioural barriers, and foster collaboration around a common vision. Optimal municipal climate leadership occurs when the leadership of elected officials and municipal is congruent, though networks play a significant role by amplifying municipal sustainability leadership. They support staff and elected officials leadership within municipalities, provide more information and funding to grow the capacity of municipalities to develop instruments, to the point that conditions under which municipalities are driving climate action are changing.

This paper hopes to contribute to better understand under what conditions municipalities drive change.

There is an international scholarly recognition that municipalities should be further explored and considered important actors in the Canadian and international climate change governance. Gore (2010) and Robinson and Gore (2015) highlighted that we are yet to understand the extent to which municipalities are involved in climate governance in Canada. This article directly addresses this gap in the current scholarly literature and explores the expansion of climate municipal leadership with the aspects of interviews.

This study delineates the effect of cover thickness on reinforced concrete (RC) columns and beams under an elevated fire scenario. Columns and beams are important load-carrying structural members of buildings. Under all circumstances, the columns and beams were set to be free from damage to avoid structural failure. Under the high-temperature scenario, the RC element may fail because of the material deterioration that occurs owing to the thermal effect. This study attempts to determine the optimum cover thickness for beams and columns under extreme loads and fire conditions.

Cover thicknesses of 30, 40, 45, 50, 60 and 70 mm for the columns and 10, 20, 25, 30, 35, 40, 50, 60 and 70 mm for the beams were adopted in this study. Both steady-state and transient-state conditions under thermomechanical analysis were performed using the finite element method to determine the heat transfer through the RC section and to determine the effect of thermal stresses.

The results show that the RC elements have a greater influence on the additional cover thickness at extreme temperatures and higher load ratios than at the service stages. The safe limits of the structural members were obtained under the combined effects of elevated temperatures and structural loads. The results also indicate that the compression members have a better thermal performance than the flexural members.

Numerical investigations concerning the high-temperature behavior of structural elements are useful. The lack of an experimental setup encourages researchers to perform numerical investigations. In this study, the finite element models were validated with existing finite element models and experimental results.

The obtained safe limit for the structural members could help to understand their resistance to fire in a real-time scenario. From the safe limit, a suitable design can be preferred while designing the structural members. This could probably save the structure from collapse.

There is a lack of both numerical and experimental research works. In numerical modeling, the research works found in the literature had difficulties in developing a numerical model that satisfactorily represents the structural members under fire, not being able to adequately understand their behavior at high temperatures. None of them considered the influence of the cover thickness under extreme fire and loading conditions. In this paper, this influence was evaluated and discussed.

Digital Signal Processing requires continuous, rapid response to an incoming data stream. Software applications that run on a DSP must execute in real‐time to satisfy that requirement. In addition, the cost must be very compact to meet stringent hardware space requirements.

Conceptual interpretations of sustainability and resilience are widening with discursive use and altering the relationship and understanding of both concepts. By using three city case studies in the USA, this paper aims to consider which conceptual interpretations are operational and what is being measured in the context of city policy, municipal planning and built environment practice. With increasing pressures of urbanisation, it is imperative to consider which conceptual interpretations of resilience and sustainability are being measured in frameworks for the built environment if Risk-Informed Sustainable Development across multiple sectors is to be delivered.

Three case studies with semi-structured interviews have been thematically analysed to explore how sustainability and resilience have been operationalised at policy, planning and practice levels.

City policies, municipal planning and practitioners are working with different interpretations. Collectively Risk Informed Sustainable Development is not formally recognised. Policies recognise GHG reductions and natural hazard events; planning guidance stipulates Environmental Impact Assessments based on legal requirements; and practitioners consider passive-survivability and systematic thinking. Across the sectors, the Leadership in Environmental and Energy Assessment Method provides a common foundation but is used with varying requirements.

Decision-makers should incorporate risk-informed sustainable development, update codes of practice and legal requirements leading to exemplary practice becoming normalised.

Passive-survivability should be affordable and adopt risk-informed sustainable development principles.

Three US city case studies with data collected from interviews have been analysed simultaneously at policy, planning and practice levels. Interrelated implications have been outlined on how to improve decision-making of sustainability and resilience across sectors.