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A numerical study is conducted for natural convection dominated melting inside discretely heated rectangular enclosures. This study finds applications in the design and operation of thermal energy storage units and the cooling of electric equipment. Results show the benefits of discrete heating over uniform heating for optimizing the melting process. For enclosures of high aspect ratios (A ∼> 4), configurations leading to well controlled heat source temperatures and long melting times are obtained. For cavities of low aspect ratios (A ∼< 4), it is found that the source span η is the most influential parameter. For η ∼ < 0.45, the melting times are shorter and the heat source temperatures remain equal and moderate during the entire melting process. A map for determining the cavity size and the source distribution that optimizes the melting process is presented.

Presents a physical model for determining the effective thermal conductivity of a two‐phase composite medium with fixed or moving interfaces. A rigorous numerical method for removing oscillations in the thermal field is proposed. The methodology is based on the volume averaging technique with the assumption that the phases may coexist at a temperature different from that of fusion. The analysis reveals that the effective conductivity of a two‐phase medium is dependent on the phase volume fractions, on their thermal conductivities and on a constitutive constant which determines the geometric structure of the medium and the nature of the interface (fixed or moving). The results for the one and two dimensional conduction‐dominated phase change problem show that the oscillations produced by previous fixed‐grid methods are eliminated.

This chapter discusses how society can be more involved in climate research and policy as a more socially equitable and just way of tackling future climate impacts through the lens of education. The first section discusses previous and contemporary social and political conditions in relation to increased and more equitable and just citizen engagement in climate action in the science–policy domain. The second section then explores how collaborative education approaches through Education for Sustainable Development (ESD) can be ramped up to catalyse increased citizen engagement in climate action. The chapter concludes by critically discussing future directions for research in ESD and climate change as a more inclusive and just form of climate governance.

To study the effects of velocity correction schemes for a temperature transforming model (TTM) for convection controlled solid‐liquid phase‐change problem.

The effects of three different solid velocity correction schemes, the ramped switch‐off method (RSOM), the ramped source term method (RSTM) and the variable viscosity method (VVM), on a TTM for numerical simulation of convection controlled solid‐liquid phase‐change problems are investigated in this paper. The comparison is accomplished by analyzing numerical simulation and experimental results of a convection/diffusion phase‐change problem in a rectangular cavity. Model consistency of the discretized TTM is also examined in this paper. The simulation results using RSOM, RSTM and VVM in TTM are compared with experimental results.

In order to efficiently use the discretized TTM model and obtain convergent and reasonable results, a grid size must be chosen with a suitable time step (which should not be too small). Applications of RSOM and RSTM‐TTM yield identical results which are more accurate than VVM.

This paper provides generalized guidelines about the solid velocity correction scheme and criteria for selection of time step/grid size for the convection controlled phase change problem.

Understanding the factors that contribute to the growth of sediment delta lobes in river systems has significant benefit towards protecting civil and social infrastructure from severe weather events. To develop this understanding, this paper aims to construct a three‐dimensional numerical model of a sediment delta depositing on to a two‐dimensional bedrock basement entering an ocean at a constant sea‐level.

The approach used adapts and applies techniques and schemes previously used in building numerical heat transfer models of melting systems. Particular emphasis is placed on modifying fixed grid enthalpy like schemes.

The resulting model provides important insight on the features that control the partition of sediment delta deposition between the land and ocean domains. The model also illustrates how tectonic subsidence may control the rate of delta growth.

This is the first numerical heat transfer inspired model of a three‐dimensional sediment delta deposit over both land and ocean domains. The problem has scientific merit in that it represents a melting‐like moving boundary problem with two distinct moving boundaries and a space/time dependent latent heat. Further, this work is a necessary first step towards building a comprehensive understanding of how to restore delta systems to protect civil and social infrastructure.

Explains that segregation processes during the solidification of a binary alloy occur at two distinct length scales: on the microscopic length scale of the crystal interface, in the two‐phase mushy zone, segregation is controlled by solid state mass diffusion; and, on the macroscopic scale of the process, segregation is controlled by the convective transport of the molten metal. Concludes that developing models that can capture both these scales is a challenge. Introduces a bi‐level grid, and uses a macro grid on the scale of the process for the solution of equations describing macroscopic heat and mass transport. Details how each node point in the macro grid is associated with a micro grid on which equations describing the microscopic phenomena in the mushy region are solved. In this way, develops a dual‐scale model of segregation during the solidification of a binary alloy. On investigating the unidirectional solidification of a binary alloy, demonstrates that this dual‐scale model is able to capture both the macro and micro‐scales in a single numerical treatment.

Education in sustainability science is largely ignorant of the implications of the environmental crisis on inner dimensions, including mindsets, beliefs, values and worldviews. Increased awareness of the acuteness and severity of the environmental and climate crisis has caused a contemporary spread of hopelessness among younger generations. This calls for a better understanding of potential generative forces of hope in the face of climate change. This paper aims to uncover strategies for fostering constructive hope among students.

This study examines, through qualitative interviews, the characteristics of constructive hope amongst proactive students enrolled in university programs related to global environmental challenges. Constructive hope describes a form of hope leading to sustained emotional stability and proactive engagement through both individual and collective actions.

The findings are presented according to four characteristics of constructive hope: goal, pathway thinking, agency thinking and emotional reinforcement. This shows how students perceive the importance of: collaboratively constructing and empowering locally grounded objectives; reinforcing trust in the collective potential and external actors; raising students’ perceived self-efficacy through practical applications; teaching different coping strategies related to the emotional consequences of education on students’ well-being.

We outline practical recommendations for educational environments to encourage and develop constructive hope at multiple levels of university education, including structures, programs, courses and among students’ interactions. We call for practitioners to connect theoretical learning and curriculum content with practice, provide space for emotional expressions, release the pressure from climate anxiety, and to foster a stronger sense of community among students.

Celebrities communicating about environmental sustainability on social media have the power to inspire young adults to engage in pro-environmental behavior, such as reducing their consumption behavior or only buying local and organic food. However, at the same time, celebrities’ carbon-rich and luxurious lifestyles might generate skepticism when they preach about environmental action. Thus, this study aims to shed light on the effects of celebrity pro-environmental messages on young adults’ perceived authenticity and greenwashing and, subsequently, on young adults’ pro-environmental behavior. Moreover, this study examined the moderation effect of congruent (vs incongruent) messages in the celebrity’s social media profile depicting an environmentally friendly (vs unfriendly) lifestyle.

The authors conducted a 3 (celebrity pro-environmental messages: with concrete action claim vs without vs control group) x 2 (celebrity message-lifestyle congruence: congruent vs incongruent) between-subjects experimental study (N = 400) with young adults (16–26 years old).

Results showed a significant positive effect of celebrity pro-environmental messages with concrete green action claims on authenticity perceptions only when the social media profile depicted a congruent environmentally friendly lifestyle. Moreover, higher perceived authenticity of the celebrity by social media audiences led to a higher likelihood of young adults’ engagement in pro-environmental behavior.

To the best of the authors’ knowledge, this study is the first to consider celebrity message characteristics and young adults’ perceptions of authenticity and greenwashing when investigating the effects of celebrity pro-environmental messages on young adults’ pro-environmental behavior.

The purpose of this study is to better understand how students of French agricultural education position themselves in the face of climate change and get involved in its fight.

This paper is based on a survey carried with 300 French students enrolled in the Brevet des Techniciens Supérieurs Agricoles class. A statistical analysis highlights the sensitivity of students to climate change and a simple econometric modelling examines the determinants of this sensibility. Finally, a qualitative study based on semi-directive interviews characterise the role of students as intermediaries of knowledge and innovative practices.

This study reveals that if the students ensure a function of intermediation inside rural where they act as true operators of institutional change, their role is less significant inside school and social networks.

The analyses should be further developed by examining more precisely the place and roles of students in the creation and coordination of local collective structures acting for the defence of the climate.

The results show that the territories and the projects developed there can be relevant points of reference for introducing innovative teaching approaches to introduce climate change in the classroom.

Young people’s commitment to the fight against climate change is strengthened by their concrete involvement in territorial development projects. Indeed, those territories specifically in rural areas appears as a space for innovation in environmental practices.

The originality of the study lies in its focus on the role of schools, living territories social networks as cultural spaces for shaping and transforming young people’s beliefs about climate change.

This study provides real-world evidence for the relationship between strategic communication from a global/multinational perspective and the effectiveness of corporate message strategies in the context of environment risk communication. Among sustainability issues, particulate matter (PM) air pollution has threatened the health and social wellbeing of citizens in many countries. The purpose of this paper is to apply the message framing and attribution theories in the context of sustainability communication to determine the effects of risk message characteristics on publics’ risk responses.

Using a 2 (message frame: gain vs loss) × 2 (attribution type: internal vs external) × 2 (country: China vs South Korea) between-subjects experimental design, the study examines the message framing strategies' on publics' risk responses (i.e. risk perception, risk responsibility attribution held toward another country and sustainable behavioral intention for risk prevention).

Findings include (1) main effects of message characteristics on participants’ risk responses; (2) the impact of country difference on participants’ differential risk responses and (3) three-way interactions on how risk message framing, risk threats type and country difference jointly affect not only participants’ risk perception and risk responsibility attribution but also their sustainable behavioral intention to prevent PM.

Although this study used young–adult samples in China and South Korea, the study advances the theory building in strategic environmental risk communication by emphasizing a global/multinational perspective in investigating differences among at-risk publics threatened by large-scale environmental risks.

The study's findings provide evidence-based implications such as how government agencies can enhance the environmental risk message strategy so that it induces more desired risk communication outcomes among at-risk publics. Insights from our study offer practical recommendations on which message feature is relatively more impactful in increasing intention for prosocial behavioral changes.

This study on all measured risk responses reveals important differences between at-risk young publics in China and South Korea and how they respond differently to a shared environmental risk such as PM. The study's findings provide new evidence that media coverage of global environmental issues needs to be studied at the national level, and cross-cultural comparisons are imperative to understand publics’ responses to different news strategies. Thus, this study offers implications for practitioners to understand and apply appropriate strategies to publics in a social way across different countries so as to tailor risk communication messaging.

This study offers new insights to help connect message framing effects with communication management practice at the multi-national level, providing recommendations for government communication practitioners regarding which PM message features are more likely to be effective in forming proper risk perception and motivate sustainable actions among at-risk publics in different countries.