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A Systematic Review of the Urban Heat Island Effect:
Urban Form, Landscape and Planning Strategies

In urban areas, the temperature decreases due to the evapotranspiration
and shade effects of parks and green spaces. It was found in the researches
that green spaces in general are colder than other areas. In these researches, it
was also obtained that parks and green spaces are effective in reducing urban
heat island effects and reducing cooling energy consumption, especially in
summer. Moreover, it was concluded that it also balances the hot air wave
caused by building materials in summer (Mirzaei and Haghighat, 2010;
Mohajerani et al., 2017; Bai et al., 2018; Gago et al., 2013; Antoszewski et al.,
2020; Filho et al., 2021). Water surfaces have a role in reducing the urban heat
island effect as well. Studies showed that water surfaces can reduce the air
temperature by about 2.5 °C (Jin et al., 2005; Bowler et al., 2010; Gunawardena
et al., 2017). But it is known that this effect is seasonal, especially in streams. In
spring and summer, the water surfaces cool the environment, while in autumn
and winter, the ambient temperature affects a certain amount (Wu et al., 2019).
It is stated that trees and vegetation are generally the most effective and
least costly in reducing the urban heat island effect and improving the quality
of the urban environment. Tree canopies are used as an aspect providing shade
in pedestrian areas (Norton et al., 2015; Jaganmohan et al., 2016; Broadbent et
al., 2018; Taleghani, 2018). The shading effect is considered to be an effective
method for reducing radiation and temperature in the summer season (Pataki
et al., 2011; Taleghani, 2018; Hu et al., 2020; Park and Guldmann, 2021). The
size and amount of shade of trees depends on the density of the canopy. Trees
with broad leaves and dense tops create a high-quality shade effect (Shashua-
Bar et al., 2010; Lin et al., 2010; Meier and Scherer, 2012; Antoszewski et al.,
2020). Shades of trees and vegetation also have a reducing effect on energy
consumption (Akbari and Konopacki, 2005; Gago et al., 2013; Antoszewski
et al., 2020). It was found that vegetation solely provides a savings of up to
about 10% in cooling the buildings (Robitu et al., 2006; Gago et al., 2013).
Green roof applications, which are preferred especially in foreign countries, are
also considered as an effective method of minimizing the urban heat island
effect. In many studies, it was revealed that green roofs reduce the temperature
around them by about 10-15 °C and increase the thermal insulation of buildings
(Chudnovsky et al., 2004; Oberndorfer et al., 2007; Lehmann, 2014; Jaganmohan
et al., 2016; Antoszewski et al., 2020).
It is a significant requirement for cities to attach importance to green
infrastructure resources in order to manage climate change both in harmony
and in mitigating its negative effects. In addition to the adaptation and
2
mitigation phases, green infrastructure resources prevent about 70% of CO

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