Page 134 - Çevre Şehir İklim İngilizce - Sayı 1

Urban Cold Space Cooling Capacity

values results in an increase in Max_LST and SD_LST of urban cool areas. This
results from the fact that as the cool area size increases, the number of urban
areas with the proportion of impermeable surfaces situated in the cool area
boundaries increases as well.

3. The importance of Land Cover in Mitigating Heat Island Effect
The results of the study show that as the total water surface area (Water_T),
the number of water surfaces (Water_N), the average (Water_Av) and
maximum water surface area (Water_M) increase, temperature decreases.
However, results also indicate that there is a weak correlation in the negative
direction. Similar findings were reached also in previous studies (Cheng et al,
2015, Du et al, 2016, Kong et al, 2014). However, as the study is implemented
in urban area, the low amount of data on water surfaces in the total data set
constitutes a limitation in terms of forming a criterion.
Heat island effect
Normalized Difference Build up Index (NDBI), refers to the intensity of
impermeable surfaces that make up an important factor in urban heat island
effect. As NDBI value increases, average land surface temperature (A_LST)
and minimum land surface temperature (Min_LST) have also increased. NDBI,
which is an important criterion regarding two-dimensional land cover, plays an
important role in defining the LST. Especially in previous studies implemented
in grid scale, a very strong relationship was identified between urban heat
island effect and NDBI (Chen et al, 2013, Du et al 2016, Guo et al, 2015, Malik
et al, 2019). When the findings of previous studies are taken into account,
although this study expected to find a strong correlation between NDBI
and LST, the patch scale utilized by the study led to the measurement of a
relationship with medium intensity (Table 4) (Chen et al, 2013, Du et al 2016,
Guo et al, 2015, Malik et al, 2019).

Results

The spatial and characteristic features of urban cool areas play an important
role in the mitigation of the effects of urban heat island and determining the
cooling capacity. Thanks to their cooling capacity, the cool areas in urban
places cool the relatively warmer areas in their perimeters, and reduce
temperature-based risks in terms of public health. The study shows that in
environments defined as cool areas average LST was measured as 32 ºC. This
situation, which refers to a relative level of coolness, shows that urban high
temperatures pose an important threat to public health. This temperature is

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