Multi‐functionality of nature‐based and other urban sustainability solutions: New York City study

Abstract

In an increasingly urban world, developing sustainable cities is crucial for global sustainability. Urban nature‐based solutions (NBS), such as green infrastructure, are often promoted for their potential to provide several urban services. These include stormwater mitigation, improving energy efficiency of buildings, and carbon emissions mitigation, but few studies have compared the multifunctionality of NBS to conventional urban solutions providing similar services. Fewer yet have acknowledged the indirect resource (specifically climate, land, energy, water [CLEW] nexus) impacts that these solutions may have. This paper analyzes these aspects, employing a simple CLEW nexus accounting framework, and attempts a consistent comparison across different resource systems. The comparison includes direct and indirect impacts of a set of stylized—and diverse—solutions, each with different primary objectives: green roofs, representing a multifunctional urban NBS; permeable pavements targeting mitigation of stormwater flows; window retrofits targeting energy efficiency; and rooftop PV installations targeting CO2 emissions mitigation. The results highlight both the direct and total (CLEW nexus) impacts of green roofs on stormwater retention, energy use, and CO2 emissions. However, also for the studied conventional solutions with primarily a single direct function, CLEW nexus impacts spread across all measured dimensions (energy, water, and CO2) to varying degrees. Although the numerical results are indicative and uncertainty needs to be further assessed, we suggest that the development of this type of multifunctional, multisystem assessment can assist urban sustainability planning, with comprehensive and consistent comparison of diverse (NBS and conventional) solutions.

Relationships between health outcomes in older populations and urban green infrastructure size, quality and proximity

“…flood retention or reduced energy demand). Such technical 'nature-based solutions' [56] are included as green infrastructure from a strict planning perspective and would also be expected to have an influence on health and wellbeing. However, such features were difficult to identify with the existing methodology [18] and were therefore only included if identified as non-built cover.…”

Green Roof Research in North America: A Recent History and Future Strategies

“…There are three main mechanisms by which green roofs can impact land-atmosphere carbon (C) exchange: (1) The direct function of the green roof vegetation and substrate as sinks or sources for C during the lifespan of the green roof ecosystem; (2) through the C cost of the energy required for construction (embodied energy); and (3) through green roof insulative properties and impact on heating and cooling energy demand for the building and region (e.g., Kotsiris et al 2019; Rowe 2011; Sailor and Bass 2014). To quantify the total C impact of a green roof system, a life-cycle analysis considering all these aspects should be undertaken (Engström et al 2018;Kavehei et al 2018). This review focuses primarily on the first mechanism, (e.g.…”

“…Studies of C budgets in intensive green roofs with deeper substrate would also be informative -these roofs have much greater potential for C sequestration if shrubs or trees develop over time, but also incur a greater additional energy cost for construction. There is additionally a need to place such studies into context of the total carbon/energy budget for the given roof, including embodied energy and potential energy savings over the life cycle of the system (e.g., Engström et al 2018;Kavehei et al 2018).…”

Embedding the United Nations sustainable development goals into energy systems analysis – expanding the food-energy-water nexus

“…The challenge that systems modelling has in addressing the distribution of wealth, as well as the evidence of social sciences approaches to some of these challenges, is addressed further in goal 17: Partnerships towards the goals. which has been applied in many different contexts and different scales around the globe including crossboundary jurisdictions such as the Drina river basin [24], [25], for the countries of Mauritius [4] and Burkina Faso [26] as well as for the city of New York [3], [27]. Given the existence of models that directly address food availability we rank this goal as definitely required to be considered in modelling structures and easy to incorporate into optimization modelling paradigms.…”