Spatial characteristics of open park spaces and perceived warmness in a tropical city

Background: Rapid urbanization in Kuala Lumpur Metropolitan City (KLMC) has resulted in urban heat island (UHI) effect that deteriorated public health of the urban dwellers. In a motive of identifying the heat sources, this study reported the perceived warmness and the characteristics of Open Park Spaces (OPS) that induce the reported warmness of the surrounding environment in Kuala Lumpur Metropolitan City (KLMC), a tropical city of Malaysia. Methods: A cross sectional survey using structured questionnaires is conducted on randomly clustered respondents in selected localities of KLMC from January to May, 2018. Pearson correlation is performed to examine the relationship between perceived characteristics of OPS and perceived warmness of the surrounding environment according to three time slots of a day. Results: The outcomes demonstrated that respondents felt warm during nights (89%) compared to morning (75%) and afternoon (87%). Meanwhile, the existing OPS are reported to be equipped with a mix of biodiversity such as birds, rodents and insects (89%), a mix of natural plants and animal populations (88%), water bodies (88%), variety of plants (86%), well-maintained grass surfaces (80%), ornamental flowers (79%) as well as wooded pasture (78%) in their neighbourhood. As the maximum warming sensation is reported to be felt at nights, especially in the presence of water bodies (r= 0.318, p<0.01) and wooded pasture (r= 0.222, p<0.01) in the vicinity, the integration of heat ameliorators across the existing water bodies and wood pasture deemed essential to reduce the surrounding heat impacts. Conclusion: The findings of this preliminary investigation are useful for urban designers and policy makers to make tacit evidence-based decisions.

with narrow street canyons, reduced sky view factor, non-reflective and impermeable surface materials, lack of transpiring vegetation, transport flows, increased energy consumption as well as higher concentrations of urban pollutants [5,6]. The aforementioned urban complexity trap and absorb the heat from escaping into the open space, thus creating a steep temperature gradient between urban and rural areas at nights [7]. Upon intensification, UHIs induce deleterious impacts on anthropogenic energy emissions [8], thermal comfort levels [9], air quality [10], biodiversity [11] and public health [12].
Being the cultural, financial and economic hub of Malaysia, Kuala Lumpur Metropolitan City (KLMC) is among the rapidly developing metropolitan regions in the Southeast Asia. In alignment with its physical growth, periodical temperature observations revealed that KLMC was getting warmer by 0.6 °C per decade [13]. By employing weather station network, Elsayed reported an increase of 1.5 °C in UHI Intensity (UHII) in 2004 compared to a similar study done by Sani in 1985 [14]. On an important note, this study identified the appearance of more heat islands in the city center due to the absorption and retention of heat by urban materials. Later on, Yusuf et al. reported an average gain of 8.4 °C in surface temperature between 1997 and 2013 in selected zones of KLMC [15]. On top of this, urban community of an expanding city such as KLMC is deemed prone to heat impacts in the form of increased occurrences of heat waves, thermal discomforts and heat-related health implications [16].
From a large-scale survey involving 1050 respondents, Wong et al. identified that majority of the respondents reported respiratory problems (90.2%) followed by heat exhaustion (83.1%) and heat cramps (72.9%) as the health externalities of urban heat in KLMC [17]. Beside a substantial impact on the deterioration of urban quality and liveability, very little studies are dedicated on the UHI mitigation measures in the local context [18,19].
Integration of Open Park Spaces (OPS) in urban areas to counteract the deleterious impact of UHI is deemed a feasible UHI mitigation measure in the tropical context. Particularly, OPS refer to a heat mitigation strategy in which parks are integrated with open spaces that caters for sports and recreation, preservation of natural environments, provision of green space and urban stormwater management [20,21]. OPS, in the presence of greeneries, ameliorate urban heat by creating cooling buffer zones which also provide shade from direct solar radiation [22,23]. Besides, empirical evidence have shown that cooling effects from the parks can reach up to 1-7 °C based on groundbased temperature measurements [24]. According to [25], parks incorporated with greeneries provide higher levels of thermal comfort, with approximately 0.94 °C of reduced daytime temperatures. It should be noted that existing literature on the potential of parks to combat urban heat mainly centered on urban parks [26], urban gardens [27], green roofs [28], vertical greenery [29], urban trees [30] and pocket parks [31] in accordance with the size and shape. Nonetheless, the potential of OPS as a viable mean for UHI reduction is still subjected to further investigation in the tropical context.
Despite the exacerbation of UHI phenomenon in KLMC, little attempts are invested on its mitigation practices. In reference to this, the present preliminary study aims to investigate the potential of OPS to mitigate urban heat effects in a tropical setting. The first objective is to examine the perceived warmness of the surrounding environment among the local residents of selected study areas in KLMC.
The second objective is to investigate the existing characteristics of OPS that induce the reported warmness of the surrounding neighbourhood to provide insights for heat mitigations. The outcomes of this exploratory initiative are expected to highlight the potential of OPS in mitigating UHI impact for evidence-based city planning.

Design and settings
This cross sectional study used structured questionnaires to identify the perceived warmness of the surrounding environment and the existing characteristics of OPS that induce the reported warmness of the surrounding environment to provide insights for heat mitigations among the local residents of

Instrument
A structured questionnaire is developed after reviewing relevant literature on the components of OPS that have the potential to mitigate urban heat [26,27,30,31]. The questionnaire was subsequently face validated with the local experts. Basically, the questionnaire consists of two main sections. First section queried respondents' demographic information such as gender, working sector, education level, monthly income, type of residence and house price. Meanwhile, second section consists of questions on the characteristics of OPS. Seven items were listed in relation to the components in an OPS. Respondents are required to state their level of agreement using a five-point Likert scale on the characteristics an OPS that have the potential to mitigate urban heat in KLMC in accordance with three time slots of a day, namely morning, afternoon and night.

Data collection and analyses
Respondents are sampled using a randomized cluster approach. The inclusion criteria for the selection of respondents is that they must be local residents living in the study area during the data collection period. Data was collected from January to May, 2018. The collected data is analyzed in SPSS software (Version 25). A descriptive analysis is conducted to express the categorical variables in frequencies and percentages. Besides, Pearson correlation is performed to examine the relationship between perceived characteristics of OPS and perceived warmness of the surrounding environment according to three time slots of a day.

Ethical approval
The ethical clearance was acquired from University of Malaya Research Ethics Committee (Ref . No: UM.TNC2/UMREC-691) before conducting the study. Informed consent was verbally obtained and this procedure was approved by the research committee. All the data were anonymized and analyzed without identifiers.

Participant background
A total of 200 eligible responses are collected from the study area. Female respondents (58%) are of predominance compared to the males. Majority of them are working in the private sector (55%) and completed diploma (43%). More than half of their income is within MYR (Malaysian Ringgit) 2,501 -4,000 (54%). Besides, majority of the respondents are staying in terrace houses (51%) that covers an area between 501 -800 square feet (51%), with house price ranging between MYR 300,001 -500,000 (41%). The sociodemographic characteristics of the respondents are presented in Table 1. *MYR = Malaysian Ringgit

The perception of warmness and characteristics of OPS in KLMC
The agreement of the respondents on the perceived warmness and characteristics of OPS are dichotomized, in which responses for 'agree' and 'strongly agree' are added up and treated as agreement to the reported characteristics. Meanwhile, the responses for 'neutral', 'disagree' and 'strongly disagree' are considered as disagreement and, therefore excluded from the analysis. The perception of warmness and characteristics of OPS in KLMC is displayed in Table 2. The findings indicated that the majority of the respondents expressed that they felt warm during nights (89%) compared to morning (75%) and afternoon (87%). Although no temperature measurements conducted to verify with their expressed perceived warmness, the findings are still in agreement with the other studies reported for KLMC that stipulate urban heat is mostly apparent

Association between characteristics of OPS and perceived warmness in KLMC in accordance with three time slots of a day
A Pearson correlation analysis is performed between the reported characteristics of OPS and perceived warmness in KLMC to elucidate its potential in mitigating UHI in KLMC as shown in Table 3. Table 3 Pearson correlation between perceived characteristics of OPS and perceived warmness in .05) are significantly correlated with perceived warmness in the morning. Open and exposed spaces in the parks due to scarcely designed landscaping plants and water bodies can cause most of the areas of the park to be exposed to direct solar radiation in the morning.

Conclusion
In summary, this study investigated the potential of OPS to mitigate urban heat effects in a tropical setting by exploring the perceived warmness of the surrounding environment and the existing characteristics of OPS that induce the reported warmness among the local residents of selected study areas in KLMC. The findings revealed that respondents felt warm during nights (89%). As the maximum warming sensation is reported to be felt at nights, especially in the presence of water bodies and wooded pasture, the incorporation of heat reducing elements across the existing water bodies and wood pasture is essential to reduce the surrounding heat impacts. The outcomes highlighted that the existing features of OPS have to be improved to reduce the warming sensation experienced by the residents in KLMC.

Figure 1
Selected study areas in Kuala Lumpur Metropolitan City Selected study areas in Kuala Lumpur Metropolitan City