*4.1. Relation between Park Types, LST and PCI*

Following the method in Section 3.2, the LST map based on the 07 July 2019 satellite image was derived (Figure 2a). Generally, the mean LST of the parks was lower than the mean LST of Zhengzhou city. We analyzed the PCI of all the selected samples by comparing the five park types (Table 2), and results show that the PCI of five park types were different (Table 5): The average temperature of the theme park category is 30.01 ◦C; noticeably it is 2.14 ◦C lower than the average temperature of Zhengzhou city. Its cooling effect is the strongest, where the average PCI reached 2.76 ◦C. The urban squares had the highest temperature, with an average LST of 32.13 ◦C, which is still 0.02 ◦C lower than the average LST in Zhengzhou.

**Figure 2.** (**a**) LST map of Zhengzhou city in 07 July 2019; (**b**) Distribution of 123 parks samples; (**c**) Five park type examples: 1-urban park; 2-theme park; 3-street park; 4-linear park; 5-urban square.


**Table 5.** Statistics of LST and average PCI in different park types.

The result (Table 5) showed that PCI of the theme park category was the largest, this is related to the content of the theme park. Linear parks had the lowest cooling effect; the PCI value was only 0.64 ◦C. Meanwhile, the cooling effect of the street park category is also at a comparatively low level, with its PCI only 0.16 ◦C higher than the PCI of the street park group. The PCI of the urban square category was in the middle, it reached 1.44 ◦C, but its average LST was the hottest among the five types. So based on the results, we can conclude that theme parks have the most substantial cooling effect in Zhengzhou city, while the linear park category contributes with a less cooling effect.
