Thermal comfort and the influence of dress culture analysis based on temperature humidity index in Pontianak

In recent decades, global warming has resulted in rising temperatures worldwide, including in equatorial regions. Pontianak, situated precisely on the equator, faces environmental challenges such as high rainfall, frequently exceeding comfort tolerances in air temperatures, intense solar radiation, and persistent high humidity, impacting thermal comfort. The primary goal of this research is to evaluating thermal comfort conditions in Pontianak, primarily utilizing the Temperature Humidity Index (THI) as a key indicator. The study also investigates the influence of local dress culture and clothing choices on thermal comfort. To further measure the level of thermal comfort in Pontianak, the Temperature Humidity Index formula developed by Nieuwolt was employed. The analysis revealed that, on average, the THI during daytime was 32.87°C, indicating some discomfort perception. This is consistent with the opinions of the local community, who often express discomfort with the thermal conditions in Pontianak. These conditions also affect the clothing choices of Pontianak’s residents. Factors such as material, size, and color are among the main considerations for selecting clothing. Nevertheless, the selection of clothing ultimately depends on the body’s response to the thermal conditions in Pontianak, aiming to minimize the impact of the prevailing thermal conditions.


Introduction
According to the latest report by the World Meteorological Organization (WMO) on January 12, 2023, the year 2022 was the hottest ever recorded globally.The temperature increase was documented as 1.15°C higher than the pre-industrial period .The elevated global temperatures of the year 2022 further confirm that the past eight years (2015-2022) hold the record for the hottest Earth temperatures in history.Earth has officially experienced a temperature rise exceeding 1°C, even during periods of global wetness or La Niña occurrences [1].
Issues that arise encompass elevated levels of rainfall, air temperatures consistently surpassing comfort limits, intense solar radiation, and humidity levels conducive to achieving thermal comfort [2].Climate change has a direct or indirect impact on ecosystems, primarily through shifts in land usage, heightened CO2 emissions, air and water pollution, intensified utilization of natural resources, and the loss of biodiversity [3].In 2017, Pontianak was categorized as a 'bottom-tier city' with a livability index of 62.However, based on the latest research in 2022, the MLCI index increased to 69, elevating its status to an 'average tier city category' [4].Recorded data from the Pontianak Maritime Meteorology Station indicates that in 2022, the minimum air temperature in Pontianak reached 22.2°C, while the maximum temperature peaked at 35.8°C, with an average air pressure of 1010.6 millibars.The average wind speed in Pontianak is approximately 3.7 knots, with the highest wind speed occurring in October and November, reaching 29 knots.However, according to the Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG), in 2017, Pontianak experienced extreme temperatures around May, where temperatures occasionally reached 37°C.The intense equatorial sunlight prevents the dissipation of heat vapor, leading to high temperatures.
Air temperature serves as an indicator of thermal comfort that we experience during physical activities or sports.However, temperature is just one factor.Another influential climatic factor is air humidity, which can be used to assess human comfort perception [5].According to the International Standard Organization (ISO), thermal comfort is a complex interplay between air temperature, air humidity, airflow velocity, as well as clothing type, activity level, and occupants' metabolic rates.These factors collectively shape individuals' satisfaction with the indoor air conditions within a given environment [6].
Thermal comfort linked to the climate also shapes how people in a community dress.The impact of climate on humans can be viewed in relation to climate and ecology.This situation is evident in social and cultural aspects, such as clothing styles and the design of traditional buildings in each region [7].Although initially, clothing primarily served to protect the human body from the heat of the day and the cold of the night, even guarding against dirt.However, as human civilization progressed, the function of clothing evolved beyond mere necessity and acquired a social role.In other words, clothing can also be considered an expression of human culture [8].
Geographical conditions impact fashion in various ways.First, the climate and environment of a region can influence the materials, styles, and colors used in clothing.For instance, in hot and humid tropical areas, people might prefer lightweight and breathable fabrics like cotton or linen, in bright and vibrant colors.In colder or temperate regions, thicker and warmer materials like wool, and neutral or darker colors, could be favored.
Second, local culture and traditions also play a role in fashion.Traditional garments like the Japanese kimono, Indian sari, or Indonesian kebaya are still worn and hold significance in certain events.Moreover, customs and social norms can shape fashion in a region.For instance, in countries with a Muslim majority, modest and covering attire is a requirement.
Third, geography influences fashion through globalization and social change.Technological advancements and transportation have made it easier for people to access materials and styles from around the world, resulting in the exchange of ideas and fashion trends across cultures.The rise of social media and the global fashion industry also accelerate the spread of fashion trends worldwide and hasten fashion changes.
Various prior studies, such as The Organization for Economic Co-operation and Development (OECD) Measuring well-being, Mercer Quality of Life Index, and Monocle Magazine MLCI, have indicated that environmental conditions, including climate, are factors influencing livability.In this context, thermal comfort is linked to climate and believed to impact the local community's dressing culture.Hence, it is crucial to conduct research to determine the level of Thermal Comfort based on the Temperature Humidity Index (THI) in Pontianak and its effects on the local dressing culture.

Materials and Methods
This study employs a descriptive quantitative approach that serves as a representation of a sample from the population.The population in this research comprises students majoring in Geography Education at Tanjungpura University, spanning the cohorts of 2020, 2021, and 2022.The determination of the sample size employs the Nomogram Harry King table.Within this table, the maximum population size is set at 2000, with varying levels of error ranging from 0.3% to 15%, and a corresponding multiplying factor adjusted to the predetermined level of error [9].In this study, a 10% error rate was adopted, resulting in a sample size of 65 individuals.
This research was conducted in Pontianak to ascertain thermal comfort, represented by observation points at the Supadio Meteorological Station.Concurrently, an investigation into dressing culture was carried out in Pontianak.The dataset incorporates both secondary and primary data collected through observations and questionnaires.The data analysis encompasses the Temperature Humidity Index and the Likert scale.

Temperature Humidity Index (THI)
The Temperature Humidity Index is a method used to assess the comfort level in a particular area.The formula used is as follows:  = 0,8   + ((  )/500 ( 1) Source : [10] Where: T: Air Temperature (degrees Celsius) RH: Relative Humidity (%) THI: Temperature Humidity Index The data utilized to measure the Temperature Humidity Index (THI) consists of daytime temperature and humidity.This approach is based on previous research [11], which indicates that there is no significant temperature difference between morning and night, whereas the daytime temperature is considerably higher compared to morning and night.Moreover, daytime represents a period characterized by various social and economic activities.In this study, the temperature and humidity data used are annual data obtained from the Supadio Meteorological Station over a period of 10 years starting from 2012 until 2022.
The interpretation of Humidex with heat sensation is presented in Table 1, according to the classification by Spridonov.The temperature and humidity measurements are taken outdoors, implying that the heat sensation derived from the calculated Humidex is intended for outdoor environments [12].

Humidex range
Thermal discomfort level

Likert Scale
Using the Likert Scale as a measurement to understand the dressing culture of the community in Pontianak.The Likert Scale is a measurement used to gauge an individual's or a group's attitude, opinion, or perception towards an event or social phenomenon.The convenience of employing the Likert scale lies in its widespread utilization by researchers [13].The analysis of thermal comfort levels employs a Likert scale with five categories: Very Comfortable (VC), Comfortable (C), Neutral (N), Uncomfortable (UC), and Very Uncomfortable (VU).Meanwhile, the analysis of the influence of thermal comfort on dressing culture employs a Likert scale with four categories: Highly Influential (HI), Influential (I), Slightly Influential (SI), and Not Influential (NI).The Likert Scale is calculated using the formula: Source : [14] IOP Publishing doi:10.1088/1755-1315/1314/1/012054 Where: T: Total number of respondents who chose a particular option Pn: Score assigned to the chosen Likert scale option.
Next, the calculation of the community's perception level is carried out using the formula of the wide interval class to obtain the score range as follows: Class Interval = Total Score / Y x 100 ( 3) Source : [15] Where: Y: Highest Likert Score x Number of respondents.

Thermal Comfort Level in Pontianak
Based on the analysis, the Temperature Humidity Index (THI) according to the Humidex interpretation with the Spridonov heat sensation indicates that Pontianak has been in the 'Some Discomfort' category with a range of 30°C to 34°C over the past 10 years.The Thermal Comfort Level in Pontianak over the last 10 years can be observed in the following graph: Based on the graph, it can be observed that the year 2012 had the lowest THI level in the past 10 years, while the highest THI level within the last 10 years was in 2017.Air temperature and humidity are the primary climate parameters that influence human comfort.The variation in air temperature and humidity significantly impacts comfort during activities [16].
The significant changes in THI observed in Pontianak are influenced by various factors, elements such as topography, elevation, wind patterns, latent heat, ground cover, soil type, and solar angle impact the temperature of a region [17].The topography of Pontianak City is mostly located in the lowlands with the city's height ranging from 0 to 2 meters above sea level.This causes the area to absorb and store solar heat.In line with research conducted by [18].This is supported by research conducted by [19], urban humid heat in nearly all urban areas globally under a high emission climate change scenario by the end of the century.
The outcomes of the thermal comfort classification using the Temperature Humidity Index (THI) method align with the public perception that thermal comfort conditions in Pontianak, particularly  The variation in perception can be attributed to the degree of individual adaptation to their environment.According to Humphreys and Nicol as cited in [20], thermal comfort is also influenced by the adaptation of each individual to the external temperature in their surroundings.Individuals accustomed to hot or tropical climates tend to perceive higher temperatures as comfortable compared to those accustomed to cooler climates.
About 58.5% of the people living in Pontianak prefer THI conditions below 29°C as comfortable for their bodies.The community's perception regarding the influence of THI on comfort and productivity can be observed in the following illustration: Perception of the level of thermal comfort when outdoors during the day

Neutral Uncomfortable Very Uncomfortable Comfortable
In response to the first question (Q1), "Does high THI conditions affect comfort and work productivity?"66.15% answered that high THI conditions are 'Influential' on comfort and work productivity.For the second question (Q2), "Does dressing culture influence the choice of clothing that makes you feel comfortable in temperature and humidity conditions?" 58.46% answered that dressing culture is 'Influential' on the choice of clothing that makes them feel comfortable in temperature and humidity conditions.
Based on these responses, it can be inferred that THI conditions indeed influence comfort and work productivity.The characteristics of a hot and humid climate often disrupt outdoor activities due to thermal discomfort [2].If the body engages in strenuous physical activities, excessively hot environmental conditions can impact both productivity and physical health.Consequently, people tend to wear specific types of clothing in high temperature and humidity to minimize discomfort.

The Influence of Thermal Comfort on Dressing Culture
The temperature and humidity conditions in Pontianak slightly influence the dressing culture of the community, affecting the choice of clothing that provides comfort.The aspects of focus for Pontianak's residents include cleanliness, comfort, and social environment.Tajuddin mentioned in his research [21] that a person's dress style is influenced by many things such as culture, values inherited by community groups as well as family, environment, media, fashion trends, and personal character and also clothing not only functions to protect the body from the influence of the surrounding air, but is a means to express themselves to the wearer.
The prevailing weather conditions in Pontianak, which tend to induce discomfort, lead people to pay more attention to personal hygiene.High temperatures can stimulate sweat production, consequently, thermal comfort is influenced by relative humidity (RH), particularly when moisture is released, causing discomfort [22].Therefore, to address this, people take 2 -3 showers a day and change clothes frequently when outdoors during the day.Cleansing the body and experiencing a sense of refreshment are the benefits perceived from bathing [23].
In order to achieve a body response adaptable to thermal conditions, the community of Pontianak choose clothing selection is based on textile materials and clothing designs.Consistent with research by [24], different clothing properties also influence thermal comfort, such as fabric design with its structure, fiber composition, and porosity.Suitable clothing choices for Pontianak's residents involve breathable materials (that absorb sweat easily).Natural fibers like cotton and lightweight fabrics are commonly chosen due to their moisture-absorbing properties, keeping the body comfortable in humid conditions.This aids in minimizing discomfort and aligns with the local dressing culture.The community tends not to follow fashion trends, and cultural or religious factors do not significantly influence clothing choices.
The community is conscious of clothing types that are comfortable for the temperature and humidity conditions in Pontianak.This is evident from the questionnaire results, where respondents feel that the clothing they wear is quite comfortable for the current conditions in Pontianak.Approximately 78.46% of respondents have adapted their clothing choices to match the temperature and humidity conditions in Pontianak.

Conclusions
Over the past decade, Pontianak has experienced thermal comfort categorized as 'Slightly Uncomfortable' with the highest THI value recorded in 2017 at 34.21°C.It's noteworthy that when the THI value reaches 35°C, thermal comfort shifts into the 'Uncomfortable' category, necessitating the limitation of strenuous physical activities to prevent the risk of dehydration.
The temperature and humidity conditions in Pontianak mildly influence the local dressing culture.Primary considerations for clothing selection encompass textile materials and clothing designs.However, the choice of clothing ultimately stems from the body's response to thermal conditions in Pontianak, thus minimizing the impact of prevailing thermal conditions.
20 o C ≤ HD ≥ 29 o C Comfort 30 o C ≤ HD ≥ 39 o C Some discomfort 40 o C ≤ HD ≥ 45 o C Great discomfort, avoid exertion Above 45 o C Dangerous Above 54 o C Heat stroke imminent

Figure 2 .
Figure 2. Perception of the level of thermal comfort when outdoors during the day

Figure 3 .
Figure 3.The community's perception regarding the influence of Thermal Humidity Index (THI)