Urban Science

Open biomass burning (OBB) adversely affects air quality, climate systems, and public health. Large-scale OBB, including forest fires and crop residue burning, is prevalent in Southeast Asia (SEA), a region with agrarian countries. The characteristics of OBB have been widely studied in SEA; however, the understanding of daytime and nighttime variations in fire activity and the effects of fire production remains limited. A significant amount of particulate matter (PM) is released into the atmosphere during OBB episodes. This study employs the Visible Infrared Imaging Radiometer Suite (VIIRS) to detect active fires during daytime and nighttime from OBB in Chiang Mai, Thailand, during March–April 2020, and investigates the mass concentration of size-specific PM down to PM_0.1. The results showed that hotspots occur more often at night than during the day. The VIIRS fire detection data provided a better response to small fires and improved mapping of extensive fire perimeters. PM_0.5–1.0 showed the highest mass concentration among particle sizes. Moreover, fire hotpots show the highest correlations with PM_0.1–0.5 during the daytime and PM_0.5–1.0 during the nighttime, and the large OBB in Chiang Mai significantly contributes to ambient PM. Overall, this study offers crucial insights into particulate pollution from biomass burning.

Promoting and increasing sustainable mobility has become more of a focus in transport and mobility policies and plans. However, challenges remain in its implementation in low-density urban areas, which are usually highly dependent on private motorised transport. This study investigates how local actors and citizens in a low-density suburban area perceive the main mobility challenges and opportunities, contributing empirical evidence on how collaborative planning operationalises accessibility-oriented mobility models in low-density suburban territories, an under-researched context in sustainable mobility. It also examines how co-creation processes contribute to identifying barriers and priorities and to what extent proximity-based concepts such as the 15-Minute City, Transit-Oriented Development (TOD), and Mobility as a Service (MaaS) can be reinterpreted for low-density suburban realities. The methodological approach involved three focus groups with local actors and citizens to identify barriers, priorities, and strategies through collective discussion and co-creation. This process resulted in an agreement on eight (8) co-created strategies, revealing convergence towards promoting active modes and public transport and emphasising that accessibility depends on territorial redesign, digital integration, and inclusive governance. The findings contribute to the empirical evidence that participatory and context-sensitive approaches can enable sustainable mobility transitions in suburban areas by efficiently meeting people’s needs and aspirations.

Urban areas face rising risks from extreme heat due to climate change, intensifying thermal stress and exacerbating social inequalities. Urban climate refuges—cool, accessible indoor and outdoor public spaces that maintain their ordinary functions—are increasingly adopted as a local adaptation measure to protect vulnerable populations during heat events. This study aims to develop and test a SWOT–CAME analytical framework to evaluate and compare the maturity, equity, and implementation logic of urban climate refuge networks in three European cities with contrasting climates and governance traditions: Barcelona, Amsterdam, and Copenhagen. A qualitative multiple-case design is combined with a transparent indicator set (coverage, accessibility, and typology mix) derived from official municipal sources and planning documents. Results show differentiated pathways: Barcelona represents an institutionalized network model; Amsterdam illustrates an emerging coordinated public-health approach; and Copenhagen reflects an ecosystem-based orientation where green–blue infrastructure provides substantial passive cooling capacity but requires clearer heat-specific operational protocols. The discussion highlights the need for hybrid adaptation strategies that combine nature-based solutions with operational governance and targeted support for vulnerable groups. The paper concludes with a transferable framework for cities seeking to integrate climate refuges into resilience and climate-justice agendas.