Extending the Shared Socioeconomic Pathways at the city scale to inform future vulnerability assessments – The case of Boston, Massachusetts

Abstract

Climate change will impact cities' infrastructure and urban dwellers, who often show differentiated capacity to cope with climate-related hazards. An emerging research field, using the latest global socioeconomic and climate scenarios -namely the Shared Socioeconomic Pathways (SSPs) and Representative Concentration (RCPs) -is exploring how different socioeconomic pathways will influence future society's ability to cope with climate change impacts. While the SSPs have been extensively used at the global scale, their use at the local and urban scale has remained rare, as they first need to be contextualized and extended for the particular place of interest. In this study, we present and apply a method to develop multi-scale extended SSPs at the city and neighborhood scale. Using Boston, Massachusetts, as a case study, we combined scenario matching, experts' elicitation, and participatory processes to contextualize and make the global SSPs relevant at the urban scale. We subsequently employed the extended SSPs to explore future neighborhood-level vulnerability to extreme heat under multiple plausible socioeconomic trajectories, highlighting the usefulness of extended SSPs in informing future vulnerability assessments. The large differences in outcomes hint at the enormous potential of risk reduction that social and urban planning policies could trigger in the next decades.

Characterizing the role of socioeconomic pathways in shaping future urban heat-related challenges

“…The SSPs are global (O'Neill et al, 2017) and should be regionally and locally extendedi.e., contextualized (Kriegler et al, 2012) to increase their suitability for regional studies (van Ruijven et al, 2013). A growing number of studies have developed extended SSPs for specific regions, e.g., the Mediterranean coast (Reimann et al, 2018), the Barents region (Nilsson et al, 2017), West Africa (Palazzo et al, 2017), Tokyo (Kamei et al, 2016), Europe Kok et al, 2019), Boston (Lino et al, 2019), and the US Southeast (Absar and Preston, 2015). Although regional extensions of the SSPs are mainly stand-alone publications, we consider as critical to include the scenario development step in this paper in order to provide a comprehensive and complete approach to assess future climate risks in urban areas under multiple plausible futures (that is, from the design of the scenarios to the assessment of future climate impacts).…”

Disentangling the contribution of socioeconomic pathways to future climate-related risks : The case of heat stress

“…The SSPs are global (O'Neill et al, 2017) and should be regionally and locally extended -i.e., contextualized (Kriegler et al, 2012) -to increase their suitability for regional studies (van Ruijven et al, 2014). A growing number of studies have developed extended SSPs for specific regions, e.g., the Mediterranean coast (Reimann et al, 2018), the Barents region (Nilsson et al, 2017), West Africa (Palazzo et al, 2017), Tokyo (Kamei et al, 2016), Europe (Rohat et al, 2018;Kok et al, 2019), Boston (Lino et al, 2019), and the US Southeast (Absar and Preston, 2015). Although regional extensions of the SSPs are mainly stand-alone publications, we consider as critical to include the scenario development step in this paper in order to provide a comprehensive and complete approach to assess future climate risks in urban areas under multiple plausible futures (that is, from the design of the scenarios to the assessment of future climate impacts).…”

“…In view of the detailed narratives and of the high level of quantification it provides -combined with its cost efficiency and the great confidence in the consistency with the global SSPs -this approach shows great potential to be taken on board by the IAV community to develop regional and/or sectoral SSPs. It should be pointed out, however, that this approach has yet to be used by the IAV community, since no published studies has employed this approach as of mid-2019 (exception made of Lino et al (2019) -which I co-authored).…”

“…Regional extensions of the global SSPs have rapidly expanded in the literature over the past few years, with for instance regional extended SSPs for the Barents region (Nilsson et al, 2017), the Baltic Sea (Zandersen et al, 2019), Southeast US (Absar and Preston, 2015), West-Africa (Palazzo et al, 2017), Europe (Rohat et al, 2018;Kok et al, 2019), and New Zealand (Frame et al, 2018). However, the extension of SSPs in urban areas have been very scarce until now, with to my knowledge only two published sets of extended at the city scale, in Tokyo, Japan (Kamei et al, 2016) and Boston, US (Lino et al, 2019) -although other city-scale extensions are currently ongoing, e.g. in the city of Flensburg, Germany .…”

“…Examples of sectoral extensions include extended SSPs of urban and population development worldwide (Jones and O'Neill, 2016;Murakami and Yagamata, 2016;Li et al, 2019), in coastal areas (Merkens et al, 2016), in the Mediterranean coast (Reimann et al, 2018) and in large cities (Hoornweg and Pope, 2017), and extended SSPs for public health (Ebi, 2013;Sellers and Ebi, 2018), for the water sector worldwide and in China (Wada et al, 2016;Yao et al, 2017), for forestry (Kemp-Benedict et al, 2014;Nepal et al, 2019), for fisheries (Maury et al, 2017), and for food security worldwide and in a few specific regions (Hasegawa et al, 2015;Mason-D'Croz et al, 2016;Palazzo et al, 2017). Examples of regional extensions include extended SSPs for the Barents region (Nilsson et al, 2017), the Baltic Sea (Zandersen et al, 2019), Southeast US (Absar and Preston, 2015), Europe (Kok et al, 2019), Tokyo (Kamei et al, 2016), Boston (Lino et al, 2019), and New Zealand (Frame et al, 2018).…”