# Urban Vulnerability Assessment of Sea Level Rise in Singapore through the World Avatar
## 2 Background  
### Sea Level Rise  
Sea level rise is a major consequence of climate change and anthropogenic greenhouse gas emissions, primarily driven by the thermal expansion of seawater, melting of glaciers and ice sheets, as well as freshwater mass exchange between oceans and land water reservoirs [17]. The Intergovernmental Panel on Climate Change (IPCC) reported that the average rate of sea level rise has been steadily increasing between 1901 and 2018 from 1.3 mm/year to 3.7 mm/year [18]. This increase is expected to continue throughout the coming century due to the rise in cumulative carbon emissions across nearly all considered scenarios and modelled pathways [18]. Singapore's Third National Climate Change Study also projects that sea levels around Singapore's coast will continue to rise until 2100 [19]. The impacts of this sea level rise include land erosion, coastal flooding, loss of biodiversity [19], and subsequent economic loss associated with affected land areas and infrastructures [14]. Sea level rise accelerates the deterioration of low-lying buildings and infrastructure networks through coastal flooding, which weakens infrastructural structure and increases the risk of building collapse [20]. Furthermore, these risks associated with buildings can lead to high costs for repair and reconstruction, as well as decrease property values [14]. Additionally, sea level rise causes population displacement which disrupts local economies and changes the distribution of communities [20; 21]. Other assets at risk, including cultural sites, historic landmarks, heritage trees, tourist attractions, and museums, carry intangible significance and hold important cultural, historical, and anthropological values [3; 22]. A study found that resettling coastal populations further inland could endanger additional archaeological sites [23] located inland. This underscores the complexity of sea level rise risk mitigation and highlights that a multifaceted approach is required that considers both populations at risk and cultural sites, amongst other factors. At the same time, while most conventional impact analyses focus on the ecological or economic effects of sea level rise, there is a significant lack of research on the concurrent study of the social values that may be lost with the submersion of cultural sites [2]. The narrow focus on specific domains (i.e., economic or cultural only) hinders the holistic understanding of the full spectrum of impacts associated with sea level rise. Efforts to mitigate sea level rise risk include integrated and localised planning for impact analysis and prevention [24], as well as the implementation of coordinated strategies that consider both current and future climatic conditions [25]. Integrated spatial planning has been implemented to mitigate risks by identifying and limiting development in flood-prone, vulnerable areas [25]. To ensure effective implementation, it is essential to employ interdisciplinary and transdisciplinary approaches, utilising data and knowledge across various scales in coastal risk managing [26; 27]. However, achieving effective risk mitigation is often challenging due to disjoint datasets and the resulting silos. Open-source data required for vulnerability analysis come from various sources in vastly different formats. Building datasets may come in a Geography Markup Language (GML) format, with additional open-source data presented as various user-defined tag and string values [28] that are difficult to integrate. Other datasets sourced from government open data portals may be in Comma-Separated Values (CSVs) or GeoJSON formats [29]. This underscores the need for improved interoperability among datasets. The complexities of sea level rise scenarios highlight the need for an enhanced methodology to create a versatile tool that offers well-rounded insights into localised impact assessment. Such a tool must offer comprehensive insights that account for diverse environmental, social, economic, and infrastructural factors [6].