The relationship between climate change impacts on urban heat island and water demand for urban green spaces

The high rate of urbanization has resulted in higher temperatures in many cities owing to the alteration in energy balance which has ultimately exacerbated climate change effects. Consequently, the ambient temperatures of many megacities in the world are continuously increasing, leading to severe heatwaves and increased Urban Heat Island (UHI). Several mitigatory measures have been considered, including increasing albedo, cool pavements, cool roofs, urban lawns, urban trees and green roofs. In particular, the use of vegetation and urban green space, particularly trees, is a more sustainable approach. However, meeting the water demand for irrigating urban green space is a key challenge, especially in arid and semi-arid regions. To maximize urban water usage, a balance between urban energy and water demand must be achieved. Hence, it is very vital to estimate the total water requirements for indoor and outdoor usage using water resource modelling tools. Within this context, this paper discusses the nexus between climate change effects, UHI and water demand for urban green spaces. This paper focuses on the various environmental and water modelling tools for estimating urban water demand for indoor and outdoor usage. Additionally, this paper provides sustainable water resource management strategies and approaches for mitigating UHI and climate change effects.