Sustainability

While airports have always had an uneasy relationship with the environment, the relationship has evolved dramatically in recent years. On the one hand, greenhouse gas (GHG) emissions have become a much stronger cause for concern. The global character of the GHG problem challenges established patterns of thinking about airport environmental impacts. At the same time, the canonical airport environmental problem, noise, has been transformed as the result of improving capabilities to redistribute it through procedures enabled by advanced navigation technologies. In this setting, concepts such...

The aviation sector in California is facing increased pressure to reduce its carbon footprint, leading to a growing interest in alternative fuel aviation (AFA) technologies such as sustainable aviation fuel (SAF), as well as electric- and hydrogen- powered aircraft. The report develops a California Aviation Energy Model (CAVEM), examining various AFA technologies and analyzing possible policy options. The analysis emphasizes the importance of SAF in the short term, with projections indicating sufficient supply for intrastate flights and capped vegetable oil-based fuel consumption. Long-...

Urban science seeks to understand the fundamental processes that drive, shape and sustain cities and urbanization. It is a multi/transdisciplinary approach involving concepts, methods and research from the social, natural, engineering and computational sciences, along with the humanities. This report is intended to convey the current “state of the art” in urban science while also clearly indicating how urban science builds upon and complements (but does not replace) prior work on cities and urbanization in many other disciplines. The report does not aim at a fully comprehensive synopsis of...

From a transport perspective, increasing active travel –and walking in particular– is crucial for the future of sustainable cities, as reflected in global decarbonisation policies and agendas. Further, walking is much more than a mere mode of transport: it provides a fundamental social function, fostering vibrant cohesive communities. Arguably, walking and its associated infrastructure –sidewalks– should rank among the highest priorities for planning authorities. However, efficiency- and speed-driven urbanisation has gradually reallocated street space to private cars, leading to...