Resilient and Sustainable Cities - Chapter 24: Predictive modeling for reforestation of cities to mitigate climate change impacts

Global trends of urbanization continue at an unprecedented rate. In combination with global warming, this can impact urban residents and the surrounding environment through processes such as heatwaves, especially in sparsely vegetated areas. This indicates a need for gaining a better understanding of how urbanization and climate change interact, and what approaches can be used to reduce their impacts. Here, three reforestation scenarios, low, medium, and high tree densities, were considered as model tree coverage across the City of Geelong, one of the fastest growing cities in Australia. GIS-based three-dimensional (3D) visualization of tree planting scenarios was applied and was used to assess land surface temperature (LST) in relation to tree attributes and to estimate the potential of reforestation in CO2 sequestration projected from 2030 to 2050. Our 3D models demonstrated a noticeable transformation in landscape view particularly when visualized and compared to the areas of low tree cover. It was also found that the areas supporting more trees with larger crowns had lower LST and were capable of reducing the heat. Tree plantation was observed to have the potential of absorbing CO2 with an increased rate of sequestration through density levels and time, although the amount of CO2 sequestrated is highly likely to differ depending on growth and geographic characteristics. Yet, combined with other strategies, urban reforestation could be among effective options for mitigating urban warming and climate change, further aiding planners and policy makers to create more sustainable and liveable cities.