The Mitigative Potential of Urban Environments and Their Microclimates

Abstract

Cities play a crucial role in climate change: More than 50% of the growing population lives in cities producing most of the global GDP but also 78% of greenhouse gases (GHG) responsible for climate change. Moreover, due to their highly modified land-use and intensive activities, cities are at the forefront of the most rapid environmental and climatic change ever experienced by mankind. Yet, cities' potential to mitigate both climate change and their own environment is underexploited. This paper explores ideas related to the potential of urban environments to modify their microclimates, reflecting on the overlapping potential between mitigative and adaptive actions. These actions in cities can not only tackle some of the largest contributing factors to global climate change but offer short-to medium-term benefits that could drive more immediate socioeconomic and behavioral changes. This review proposes and discusses a new preliminary definition of urban environments as microclimate modifiers-Mitigative urban Environments and Microclimates (MitEM)-and calls for further research into: (a) inter-connecting the full range of mitigative and adaptive initiatives already being undertaken in many cities and maximizing their input systemically; (b) developing a common and holistic definition of MitEM; (c) promoting its uptake at policy level and amongst the key stakeholders, based on its social and public value beyond the environmental.

Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa

“…Anthropogenic emissions and air pollution are significant drivers of temperature rises in major urban areas worldwide (Taha, 1997;Ryu and Baik, 2012;Ma et al, 2017). Waste heat and exhaust emissions from motor vehicles and industrial combustion cause warming of cities resulting in changes in microclimates urban areas (Schiano-Phan et al, 2015;Soltani and Sharifi, 2017). The marked increase in urban temperature compared to the neighbouring non-urban areas is known as the urban heat island effect (Oke, 1982;Gallo et al, 1993).…”

Heat stress risk and resilience in the urban environment

“…Compared to mitigation, adaptation can only decrease the exposure to heatwaves but not the intensity of heatwaves as defined by the Intergovernmental Panel on Climate Change (2007). The difference between adaptation and mitigation is, nevertheless, not so evident (Hatvani-Kovacs & Boland, 2015;Schiano-Phan, Weber, & Santamouris, 2015). Adaptation techniques that require the interaction with the built environment; such as movable shadings or nocturnal, natural ventilation; decrease cooling demand, air temperatures, the amount of waste heat generated and consequently UHIEs.…”

Numerical Study of Balancing between Indoor Building Energy and Outdoor Thermal Comfort with a Flexible Building Element

“…Various studies have been conducted using the thermal comfort index specified for outdoor settings in urban studies. Methods for improving urban microclimates include the use of more appropriate materials, increased use of green spaces, cooling sinks for heat dissipation, and proper layout of urban canopies [14]. These methods are for outdoor spaces such as those in schools [15] to improve microclimate conditions.…”