Infrastructure systems have typically been designed under assumptions of stability, yet the conditions cities face are increasingly uncertain and difficult to predict. This perspective argues that to respond effectively to the uncertainty brought about by changing conditions, infrastructure must shift from rigid to flexible systems. We conceptualize flexibility as the capacity of infrastructure to render human-centered affordances (i.e. realized infrastructure services that enable human capabilities) across six levers: spatial, quantity, temporal, configurable, functional, and institutional. We explore these levers in the context of urban shrinkage and transportation systems, and we discuss their implications for infrastructure management, trade-offs and risks, equity, and education. This perspective offers a structured lens for exploring where, how, and for whom flexibility should be embedded in infrastructure systems facing uncertainty, with implications that extend beyond transportation to water, energy, and other critical infrastructures.
Against the backdrop of increasing coastal risks driven by climate change, sea-level rise and intensifying anthropogenic pressures, understanding the performance and limitations of shoreline-protection systems has become a major scientific and policy concern. This review examines the evolution, effectiveness and management challenges of coastal-protection strategies, with particular attention to West Africa and the Gulf of Guinea. A structured literature search covering 2000–2025 was conducted using Scopus, Web of Science Core Collection, ScienceDirect, African Journals Online, Google Scholar and supplementary citation tracking. After screening, 64 publications were retained for comparative critical narrative synthesis. The evidence shows that coastal erosion results from interacting natural and anthropogenic drivers, including wave and sea-level variability, dam-induced sediment deficits, port development, sand mining, rapid urbanisation and shoreline armouring. Hard-engineering structures remain the dominant response in West Africa and can provide short-term local stabilisation; however, their long-term performance is often constrained by downdrift erosion, sediment-budget disruption, ecological degradation, maintenance requirements and impacts on coastal livelihoods. Socio-economic consequences include infrastructure damage, livelihood disruption, population displacement and limited community participation. Although nature-based, hybrid and adaptive approaches are increasingly recognised internationally, their implementation and long-term evaluation remain limited in the region. The literature is also geographically concentrated and methodologically heterogeneous, with insufficient integration of physical, socio-economic and governance evidence. Future research should prioritise harmonised long-term monitoring, regional sediment-budget modelling, life-cycle assessment of protection systems and stronger coordination between science, planning and governance. Multifunctional coastal systems incorporating renewable-energy functions remain an emerging option requiring cautious, site-specific evaluation.
The building sector exerts significant pressure on planetary systems and must align with environmental limits. Although life cycle assessment (LCA) supports eco-design, it mainly enables relative comparisons and does not determine whether a building is sustainable in absolute terms. Absolute environmental sustainability assessment (AESA) addresses this limitation, but its application to energy-positive buildings remains methodologically challenging. This study proposes a consistent AESA methodology for buildings that export renewable electricity, combining attributional LCA with a system-expansion approach applied to both impacts and carrying capacities. A dwelling per occupant carrying capacity is defined and extended to account for energy export. The framework is demonstrated through a residential case study in France. The case study shows that the dwelling’s ability to comply with the planetary-boundary carrying capacity depends on its positive energy balance and the use of bio-based materials. The approach supports the practical integration of AESA into building eco-design and encourages maximising the energy production capacity of residential buildings.
By 2050, India’s residential housing demand is likely to reach 576 million units. The constructed floor area and per capita floor space consumption needed to service this demand will result in increasing demand for building materials and CO _2 emissions. While some progress has been made on reducing CO _2 emissions from the operation stage, technological advancements and implementation to reduce buildings’ ‘embodied’ carbon emissions are still lacking momentum. This study evaluates mitigation potential and decarbonisation strategies through scenario assessment for cement and steel from residential buildings. The City of Ahmedabad is taken as a case study to assess strategies for decarbonising embodied-carbon impacts of future residential buildings to be built by 2050. Based on the Intergovernmental panel on climate change sixth assessment report (IPCC AR6) framework, four decarbonisation strategies to quantify CO _2 emissions from cement and steel have been adopted for the study. Asia-Pacific Integrated Model (AIM)/ End-use model, has been used for the study to understand and forecast the potential GHG emission reduction. Results from the study show that the energy efficiency and clean technology (EECTS) can achieve 46% CO _2 emission reductions from the cement sector compared to the Reference scenario, while circular economy and sufficiency scenario (CESS) can deliver 34% can be achieved. For steel, 60.2% emission reduction from the EECTS and 48.8% from the CESS scenario can be achieved. The study concludes that attaining deep decarbonisation is feasible, but it would still necessitate higher and earlier levels of material efficiency, a scaling up of carbon capture storage (CCS) capacity, and the adoption of green hydrogen, ambitious grid decarbonisation and major advances in urban and building regulations. Furthermore, as technology alone be sufficient to decarbonise the residential building industry, the concept of sufficiency should be advanced and put into practice through knowledge and policies.
The world is set to miss the 2030 sustainable development goals (SDGs) targets especially the ones related to infrastructure access. Existing service gaps will be further aggravated by the adverse impact of climate change in years to come. The next generation of SDGs will therefore need to consider how to best address existing gaps in infrastructure services such as water, energy and transport across different SDGs in the light of increasing climate uncertainties. This paper sets out how the value of breaking down silos and leveraging interdependencies between water, transportation and energy SDG targets can help to achieve the SDGs. It argues for a new generation of cross-sectoral interdependent SDG targets with climate resilience at the centre stage as well as setting a standalone SDG for transport to leverage its wide-ranging interdependencies with other sectors. Besides reforming the SDGs agenda through a nexus approach for climate-resilient infrastructure, we argue that there are three guiding principles to unlock potential benefits. The principles include holistic policy making, sustained climate financing and planning, and delivery of climate-resilient infrastructure at scale. The aim is to promote a sustainable, interconnected approach for resilient communities and economies in the era of climate uncertainty. The paper contributes to the discourse on strategic infrastructure development in the face of global environmental change and ongoing discussions on the future of SDGs.
