Extreme climatic conditions cause a decrease in ecosystem services, the disruption of the ecological balance, and damage to human populations, especially in areas with socially vulnerable groups. Nature-based solutions applying blue-green infrastructure (BGI) against these negative impacts of climate change have an important role in planning sustainable cities. This study aims to identify priority areas and develop scenarios and strategies for spatial planning to understand the tradeoffs in approaches and to maximize the benefits of ecosystem services provided by BGI in cities with arid and semi-arid climates, using Phoenix, Arizona, a swiftly urbanizing city in the Sonoran Desert, as the study area. Using GIS-based multi-criteria decision-making techniques and the Green Infrastructure Spatial Planning model integrated with the city’s existing water structures, this study is conducted at the US census scale. The hotspots for BGI are mapped from the combined GIS-based multi-criteria evaluation and expert stakeholder-driven weighting. In the hotspots where priority areas for BGI in Phoenix are identified, the city center area with a high density of impervious surfaces is identified as the highest priority area. It is revealed that social vulnerability and environmental risks (flooding, heat) have a positive correlation in Phoenix, and stormwater management and the urban heat island are the criteria that should be considered first in BGI planning.

Over the last five decades, there has been a decline of rural communities in Taiwan due to urbanization expansion. In the past 10 years, the central government has implemented the Rural Regeneration Project (RRP) aimed at revitalization and sustainable development in rural Taiwan. During the project’s implementation, communities have faced several disasters as a result of climate change-induced extreme rainfall events. Perceptions and adaptation practices of climate change-induced extreme events are critical to community sustainability and resilience. The gap between perceived and actual risks that communities experience creates challenges for policy-makers in achieving sustainability goals. This study aims to evaluate the perceived climate change-induced flooding hazard perceptions compared to the scientific projection and actual hazard events in 287 rural communities implementing the RRP. This study revealed consistency in risk perception, in that communities facing high potential exposure to extreme rainfall showed higher awareness of various impacts of climate change. However, when comparing climate actions, communities exposed to low-potential hazard areas had a relatively higher degree of recognition of the benefits of adaptation to climate change. Moreover, 59 rural communities with low awareness and exposed to high potentials of extreme events were widely distributed among hills of western, southern, and northern Taiwan, where compound disasters such as mudslides can occur. This research suggests that there is a need to integrate climate change planning and work with communities to bridge the gap between perceived and actual climate risks. In particular, capacity training, counseling services, and implementation of adaptation practices should be integrated into institutional planning and management for providing assistance in disaster prevention, relief, and post-event restoration; also, encouraging climate actions can directly improve community resilience toward climate change. While investing in the sustainable development of rural communities is largely based on revitalizing economic development, this study revealed the link to ensure resilience and social-ecological sustainability in rural communities under climate change impacts.

Developing countries in the global south that contribute less to climate change have suffered greater from its impacts, such as extreme climatic events and disasters compared to developed countries, causing climate justice concerns globally. Ho Chi Minh City has experienced increased intensity and frequency of climate change-induced urban floods, causing socio-economic damage that disturbs their livelihoods while urban populations continue to grow. This study aims to establish a citywide flood risk map to inform risk management in the city and address climate justice locally. This study applied a flood risk assessment framework integrating a coupled nature–human approach and examined the spatial distribution of urban flood hazard and urban flood vulnerability. A flood hazard map was generated using selected morphological and hydro-meteorological indicators. A flood vulnerability map was generated based on a literature review and a social survey weighed by experts’ priorities using the Fuzzy Delphi Method and Analytic Network Process. Vulnerability indicators including demographic characteristics, infrastructure, and land use patterns were used to generate a flood vulnerability map. The results illustrate that almost the entire central and northeastern parts of the city are at high flood risk, whereas the western part is at low flood risk. The findings have implications in urban planning via identifying risk hot spots in order to prioritize resources for mitigating hazards and enhancing community resilience to urban floods.