landscape university japan

japanese

Toward a New Coastal Spatial Model for Living with Water along Osaka Bay

Paper Summary
Murakami, S.(2022) How should coastal spaces be like for living with water in the era of climate change? Identification of the cross-sectional shape of the coast in five wards of Osaka City facing Osaka Bay, Reports of the City Planning Institute of Japan, No.21-2：230-234 As a starting point for exploring how coastal spaces can support living with water in the era of climate change, this study investigated the coastal cross-sectional forms of five wards of Osaka City facing Osaka Bay. The results of the survey showed the following characteristics: Approximately 60% of the coastline is occupied for specific uses and is therefore difficult to access publicly. Of the roughly 40% of the coastline with potential for public access, about 80% have vertical waterfront faces, about 80% have either independent walls or trapezoidal levees, and roughly 90% have inland areas that are at the same height or lower than the levee base, seaward side, or top of the sloping face. Although there are 21 combinations of waterfront, levee, and inland cross-sectional forms, about 50% of the cases consist of the specific combination of a vertical waterfront, independent wall levee, and inland area at the same or lower elevation. A significant portion of the coastline contains elements that are expected to diminish visibility and accessibility from inland areas to the seaward side. Although less common, waterfront sections that are non-vertical, flat or sloped surfaces without levees, and inland areas higher than the levee or seaward side are expected to enhance visual and physical accessibility from inland to the water. The study concludes that further research is necessary to examine visual and physical accessibility from inland to the water, the historical formation of cross-sectional shapes, the applicability of cross-sectional forms in coastal reorganization, and the spatial forms related to recreational use of the waterfront.
Murakami, S.(2023) Understanding Urban Waterfront Behaviors through Social Media: An Investigation of Instagram Posts along the Coastal Areas of Osaka City, Reports of the City Planning Institute of Japan, No.22-2：117-121 This study explores the potential and limitations of using social media data—specifically Instagram posts—to understand human behavior in urban waterfront spaces. Traditional observational and survey methods have limitations in capturing both spatial and temporal variation in waterfront use. In contrast, social media offers a large volume of voluntarily posted images and text that can provide insights into where, when, and how people use waterfront areas. The research focused on publicly accessible waterfront segments in five wards of Osaka City facing Osaka Bay (Nishiyodogawa, Konohana, Minato, Taisho, and Suminoe). Place names related to waterfront locations were extracted from online maps and used as search terms to collect Instagram posts. A total of 1,329 posts were identified and analyzed. Key findings include: Behavior Identification: Of the collected posts, 1,100 posts (83%) contained identifiable user behaviors at waterfront locations. These behaviors were classified into 57 distinct types, including exercise, movement (e.g., cycling, driving), observation activities (e.g., wildlife or scenery watching), other leisure activities, and non-leisure activities. Spatial and Temporal Coverage: The posts spanned multiple waterfront sites across the five wards and covered a wide temporal range, suggesting the potential to capture diverse waterfront behaviors both spatially and temporally. Water Appearance in Posts: Approximately 67% of posts included images showing the water surface, while 31% mentioned water or water-related terms in text, indicating that water presence can be detected in social media content. However, several challenges were also identified: Detection Limitations: It was difficult to detect posts for waterfront areas without specific place names on maps, limiting coverage. Posting Biases: There were significant differences in the number of posts between sites, influenced by the presence of attractions or facilities rather than waterfront characteristics alone. Influence of User Intent: The intentions of users when posting affect what behaviors and locations are captured, and this can bias the results. The study concludes that Instagram data shows promise for broadly capturing urban waterfront behavior, but methodological refinements are needed to address detection gaps, uneven data distribution, and behavior bias. Future research should also consider qualitative analyses of how water is represented in images to deepen understanding of waterfront perception.
Murakami, S.(2024) How Cities Worldwide Are Addressing Rising Sea Levels: An Investigation Through the Resilient Cities Network's Published Documents, Reports of the City Planning Institute of Japan, No.23-2：115-121 This study examined the Resilience Strategy documents of 48 coastal member cities in the Resilient Cities Network to understand how they perceive sea level rise and what kinds of coastal responses they are developing. Sea level rise is widely recognized not only as a flood risk, but as a multi-dimensional pressure involving erosion, ecosystem loss, saltwater intrusion, tidal flooding, and conflicts with urban development. In response, many cities are moving beyond conventional hard infrastructure such as levees and floodgates. Instead, they are increasingly: Integrating nature-based solutions (wetlands, green infrastructure, ecosystem restoration) Promoting multi-stakeholder collaboration Developing context-specific strategies tailored to local conditions Importantly, the study identified three strategic directions for maintaining the connection between city and sea: Enhancing accessibility — enabling people to physically and visually experience the waterfront Increasing coastal value — strengthening urban identity, recreation, and economic vitality Preserving land–sea ecological connections — restoring and protecting coastal ecosystems The findings suggest that future coastal resilience is not only about protection, but about reimagining coastal space as a place where safety, ecology, and human experience coexist. These insights form a conceptual foundation for developing new coastal spatial models in the era of climate change.