Emerging trends and knowledge domain of research on urban green open spaces and wellbeing: A scientometric review.

Green Open Spaces (GOS) and its linkages to human health and wellbeing have received growing attention in the field of urban planning. In spite of increase in number of studies in this field, there is lack of scientometric perspective pertaining to this research domain. The purpose of the study is to map the research status and key research directions in the interdisciplinary domain: Green open spaces, public health and urban planning, using Citespace. Scientometric analysis (co-author, co-citation, co-word and cluster analysis) is conducted for 451 peer reviewed publications, primarily published in last two decades (2000-2021) in the web of science database. The study assessed influential authors, journals and documents to identify the intellectual structure and network of co-authorship and countries to understand research collaborations of this domain. As a result of this review, five emerging research trends in this domain are identified - Emerging data sources, Study areas at various spatial scales, Type of study, Assessment of urban GOS benefits and Urban planning contribution in the research area. In addition, critical review of these trends is conducted to understand corresponding challenges and opportunities. The critical analysis highlighted the need of generating evidence base appropriate for assessing GOS use and user perception, especially in developing nations capturing socio-demographic diversity. The use of Citespace for scientometric analysis facilitated the systematic understanding of this research area by visualizing and analyzing various patterns and trends. This study provides an intensive understanding of present research status and emerging trends of this research domain. Findings in this study are envisioned to provide practitioners, decision makers and researchers with promising future research directions.

Outdoor thermal performance of heterogeneous urban environment: An indicator-based approach for climate-sensitive planning.

The thermal profile of the urban built-up area is essential for reducing the impact of built-up areas on urban heat stress. This study quantifies the variations in the outdoor thermal profile of built forms in a heterogeneous urban area. A two-step process was adopted to quantify built form induced heat stress. The build form typologies referred to as Urban Built Form (UBFX) were clustered based on parameterised build form indices (sky view factor, built height etc.) using statistical data reduction. The heat stress of the categorised UBFs was then examined through field measurements and radiation simulation model. Variations in thermal variables were assessed using three indices - Cooling Potential (CP), Humidex (Hx) and Mean Radiant Temperature (Tmrt) that collectively define the thermal profile of each UBF. A novel Heat Stress Risk Index (HSRI) was conceptualised and computed to represent the aggregate risk of a particular UBF towards heat stress. It was found that among the UBFs, the medium-rise compact (UBF 4) show lowest rate of cooling, exposure to high Tmrt, and high discomfort levels throughout the day and therefore exhibit thermally stressed profile. High rise-open typologies (UBF1) have high Tmrt and Hx during the noon (12:00 to 14:00 h), but their high cooling potential reduces the thermal impact of its built form during the cooling hours (18:00 to 20:00 h). Three thermal indices provide varied aspects of thermal performance of UBFs and HSRI cumulatively represents the heat stress risk of the UBFs. This study is a proof of concept, that uses empirical evidence to demonstrate thermal variations in urban built forms during calm and clear weather conditions. Results indicate the significance of built form indices as a policy variable for framing climate sensitive urban development regulations that aim to achieve a thermally efficient built environment.