Sustainable Placemaking and Thermal Comfort Conditions in Urban Spaces: The Case Study of Avenida dos Aliados and Praça da Liberdade (Porto, Portugal)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article would benefit from a more explicit articulation of its research questions and hypotheses, as their absence weakens the clarity and focus of the study. Balancing the seasonal analysis by providing equal emphasis on both summer and winter findings is essential to present a comprehensive discussion. Furthermore, the connection between the results and the conclusions needs to be strengthened by explicitly linking recommendations to the empirical data. This will enhance the credibility and practical relevance of the study's outcomes. Finally, integrating the theoretical frameworks more effectively with the findings will better contextualize the study's contribution, ensuring a more cohesive and impactful narrative.

Detailed Recommendations for Improvement

1. Is the content succinctly described and contextualized with respect to previous and present theoretical background and empirical research (if applicable) on the topic?

Assessment: Can be improved

1. Clarify the study’s contribution to the existing body of knowledge: The introduction should more explicitly explain how this article fills specific gaps in the literature. While the theoretical background is comprehensive, it lacks a concise summary of the unique contribution of the study.

   • Add a concluding paragraph in the theoretical section highlighting the gaps addressed by the study in terms of sustainable placemaking and urban thermal comfort.

2. Streamline references to the literature: The extensive citations sometimes dilute the focus. Prioritize key references that are directly relevant to the study’s objectives to present a more concise context.

3. Stronger connection to the local context of Porto: The authors should elaborate on why Avenida dos Aliados and Praça da Liberdade were chosen for this study in the context of the broader theoretical framework. For example, how do these areas exemplify or challenge previous findings in placemaking and thermal comfort research?

2. Are the research design, questions, hypotheses, and methods clearly stated?

Assessment: Must be improved

1. Explicit formulation of research questions and hypotheses: The article does not clearly state the research questions or hypotheses. Adding a dedicated section outlining these would provide a stronger foundation for the study. For example:

   • What are the differences in thermal comfort perception between summer and winter?
   • Which microclimatic features most influence user behavior in Porto's public spaces?

2. Improved structure of the methodology section:

   • While the methods (e.g., microclimatic measurements, mental mapping) are described in detail, the rationale for their selection is underdeveloped. Include an explanation of why these methods were chosen and how they align with the research objectives.
   • Separate the description of objective and subjective approaches more clearly to enhance readability.

3. Clarify sampling criteria for participants: Provide more details about how the sample of 123 participants was selected (e.g., inclusion criteria, representativeness of the population). Explain whether this sample reflects a larger population of urban space users.

3. Are the arguments and discussion of findings coherent, balanced, and compelling?

Assessment: Can be improved

1. Balance the analysis of seasonal findings: The discussion focuses more on the summer results, leaving the winter findings less explored. Devote more attention to winter outcomes, especially regarding behavioral differences in colder conditions.

2. Clearer interpretation of results: Explicitly connect key findings (e.g., relationships between air temperature and surface temperature) to actionable recommendations for urban planning. Some conclusions currently feel overly general and not sufficiently tied to the presented data.

3. Stronger linkage between theory and results: More explicitly demonstrate how the findings support or challenge the theoretical frameworks discussed earlier (e.g., Gehl’s principles, Lefebvre’s perceived space).

6. Are the conclusions thoroughly supported by the results presented in the article or referenced in secondary literature?

Assessment: Can be improved

1. Stronger linkage between recommendations and results: Conclusions such as the importance of pedestrian-friendly elements (e.g., shaded walkways, windbreaks) should be explicitly tied to the empirical findings. For instance, point to specific data or mental maps that justify these recommendations.

2. Address study limitations in greater detail: Although limitations are mentioned (e.g., study focused on two seasons), expand this section to discuss how these constraints might affect the findings. For example, how might results differ in spring or autumn?

3. Highlight the study’s broader contribution: Emphasize how these findings can inform similar urban contexts beyond Porto, particularly in adapting to climate change.

 

 

Author Response

Dear reviewers,

Thank you very much for your comments and recommendations. Our paper benefited a lot from those comments. According, we made some updates.

The table below shows the comments and changes made.

In the paper, the modifications are highlighted with yellow colour.

Best regards,

The authors

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The paper titled "Sustainable placemaking and thermal comfort conditions in urban spaces: the case study of Avenida dos Aliados and Praça da Liberdade (Porto, Portugal)" presents a comprehensive study on the microclimate and thermal comfort in two urban spaces in Porto. The research was conducted over two seasons in 2019 - 2020, using objective microclimate measurements and subjective surveys to analyze the relationship between environmental factors and human perception. The study found significant microclimatic variability, with shaded areas being preferred during warmer seasons. The results suggest the importance of considering both objective data and subjective perceptions in urban planning, and provide insights for optimizing public spaces to enhance thermal comfort. The comments:

 

 

1.       The study only focused on the summer and winter of 2019 - 2020. This narrow time frame may not capture the full range of long-term climatic variations or rare events that could affect pedestrian behavior and thermal comfort. For example, extreme weather events outside of these seasons or gradual climate changes over years could have a significant impact on the results.The limited temporal scope restricts the ability to make long-term predictions and fully understand the adaptability of the urban spaces to different climate scenarios. This is crucial in the context of climate change, where a more comprehensive understanding of year-round and long-term effects is needed for effective urban planning.

2.       Incomplete Variable Consideration: The emphasis on microclimatic factors and thermal perception overlooked other potential influences. Air quality, noise, and socioeconomic factors were not considered, even though they could also play a role in pedestrian behavior. For instance, a noisy or polluted area might be less attractive to pedestrians regardless of the thermal comfort. Ignoring other variables may lead to an incomplete understanding of the factors that truly influence pedestrian behavior and thermal comfort. Incorporating these additional factors could provide a more holistic view and lead to more effective urban design strategies that address multiple aspects of the urban experience.

3.       Methodological Constraints: The sample size for the subjective analysis was relatively small (123 participants). While it provided some understanding of individual behavior, a larger sample could have yielded more robust and generalizable results. Additionally, the convenience sampling method might introduce biases, as it may not be representative of the entire population using the spaces. The small and potentially biased sample size in the subjective analysis limits the reliability and generalizability of the findings related to human perception and behavior. This could affect the accuracy of the recommendations for urban planners, as the results may not accurately reflect the preferences and behaviors of the broader population.

4.       Please review following literature for your reference： Liu, G., Zhang, F., 2022. Land Zoning Management to Achieve Carbon Neutrality: A Case Study of the Beijing–Tianjin–Hebei Urban Agglomeration, China.

Xia, Q.; Li, L.; Dong, J.; Zhang, B., 2021. Reduction Effect and Mechanism Analysis of Carbon Trading Policy on Carbon Emissions from Land Use. Sustainability

 

Comments on the Quality of English Language

No

Author Response

Dear reviewers,

Thank you very much for your comments and recommendations. Our paper benefited a lot from those comments. According, we made some updates.

The table below shows the comments and changes made.

In the paper, the modifications are highlighted with yellow colour.

Best regards,

The authors

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

General summary:

While this manuscript explores an important topic at the intersection of urban microclimate and public space design, several critical issues detract from its scientific rigor and overall contribution. Key concerns include unclear research objectives, insufficient justification for methodologies, and a lack of coherence in presenting results. The introduction does not adequately articulate the research gaps this study aims to address, and many of the findings presented either reiterate widely known facts or lack sufficient methodological detail to establish credibility. Below is a detailed list of comments highlighting these concerns.

 

Abstract:

The specific details of the research are described; however, there is no mention of the research background, such as which research gaps in previous studies this investigation aims to address or what it seeks to clarify.

 

Line 29: "chart method" is unclear, not a popular expression in this field.

 

Line 33 "which revealed a strong correlation between perceived thermal comfort and actual microclimatic conditions.":

  This statement is widely known fact, seems very strange as a research finding.

 

Line 32 "impacted surface temperatures", Line 36 "lower T_surf": 

The defnition of the surface is unclear. Which surface does it mean?

 

Introduction:

This section is not well-structured. Past studies are presented in a somewhat arbitrary manner, which leaves the research gaps that motivated this study unclear.  

The authors highlighted the importance of integrating public space design strategies with urban microclimate considerations, and I fully agree with this perspective. However, the authors failed to explain what specific gaps in knowledge currently exist in this field.  

For example, the mere fact that outdoor thermal environment measurements and questionnaire surveys have not previously been conducted in the target area of this study is insufficient to convince readers of the necessity or novelty of this research. Researchers worldwide have already reported numerous case studies under similar conditions of solar radiation and outdoor temperature, even if these studies were conducted in different regions or climatic zones.  

Therefore, it is essential to clearly describe which aspects remain unresolved and how this paper aims to make a new contribution in addressing these gaps.

Furthermore, even after reading the entire paper, I was unable to understand what this study sought to clarify through its investigation.

 

Line 106: The term "non-participant observation" might not be commonly used in this field. Please consider replacing it with a more appropriate term.

 

Line 113 "Wind patterns and the relationship between air temperature (AT) and surface temperature (ST) emerge as crucial elements in understanding thermal comfort.": This is textbook knowledge. Additionally, it is unclear what specific surface the authors are referring to when discussing surface temperature.

 

Figure 1:

The map on the right includes a street layout covering a significantly larger area than the measured target region. Perhaps, the authors might have intended to illustrate the urban planning role of the targeted park. However, because the map covers such a wide area, it is not detailed enough to verify the specifics of the measured target region.  

Additionally, while the legend indicates that measurement points are represented by red circles, they are shown as yellow circles on the map, which is inconsistent. Furthermore, the green areas are too faint to be discernible from the map. Lastly, the meaning of the red dashed lines is not explained in the legend.

 

Section 2.2:

This section has a significant structural issue. For instance, information such as the measurement time periods (e.g., start and end times), the time intervals of the collected data, the number of days, and the season are not presented in a unified manner but are instead scattered across different paragraphs. Additionally, it might be better to replace one of the figures in Fig. 2 with a photo showing the actual setup of the measurement equipment.

 

Table 1:

Within urban street canyons, wind direction often changes significantly over time. Regarding the wind speed measurement listed in Table 1, how were the sensors secured during measurement to obtain representative values? Additionally, what does "Grad" represent as one of the measurement items? Does it refer to global horizontal solar radiation? How were the sensors properly fixed for accurate measurement?  

The same question applies to ST. Among the various surfaces with different orientations, geometric shapes, and materials surrounding the measurement points, which specific surface temperature was measured? Typically, in urban areas, measuring globe temperature is a standard method for comprehensively evaluating the diversity of surface temperatures across various objects and the impact of direct solar radiation on the human body. Why did the authors choose not to adopt such a standard approach?

 

Line 224 "The same methodological approach was applied by Nouri & Costa (2017) [18] for Rossio square (in Lisbon).": Need to describe the outline in this paper.

 

Table 3: This table is not necessary. It contains many repetition of the main text. Reorganize the main text and removing this table would be much more helpful for readers.

 

Line 252: This paragraph abruptly appears without logical connection between the previous part.

 

Line 261 "ASHRAE manual": clarify the document, citing the source. 

 

Line 271 "wind speed was calculated by combining the maximum wind speed (MWS) recorded and the standard deviation (SD) during the measurement period, using the following formula: Wx = MWS + SD."

  This sentence causes comfusion. Wx proposed by the past study is a variable to evaluate the impact of wind conditions on the perception other than usual "wind speed". It is better to add the physical meaning of Wx.

 

Line 280: definition of "ECMWF" is not given.

 

Line 288 ", a parallel analysis was also triggered based on a subjective approach.":

Does it indicate that the questionnaire survey was conducted during the field measurements? The term 'analysis' seems odd, as analysis is usually performed after data collection, whether from measurements or questionnaires.

 

Line 308: The method of selecting respondents requires justification. Past studies have already reported the diversity of thermal perceptions among different groups, not only by gender and age but also by place of residence (e.g., tourists or local residents). Additionally, the sample sizes for the summer and winter surveys are very small.

 

Paragraph starting from line 300:

According to this part, the total number of samples is 123. Does this represent 123 unique respondents, or were there respondents who stayed in the area for an extended period and participated in the survey multiple times within a single day?

 

Section starting from Line 286: This section lacks the details of the questions, thus, the methodology is unclear.

 

Line 358: The influence of trees' evapotranspiration cannot be properly assessed by the relative humidity because the vapor transport phenomena is driven by concentration of vapor other than relative humidity. Therefore, this sentence seems odd. Apart from that, it is widely known fact that the thermal mitigation mechanism of isolated trees is dominated by shading rather than evaporative cooling.

 

Fig.4: Since the previous section doesn't provide the information about what surface tempearture was measured, Fig.4D has little meaning for readers. Surface of street surface, surrounding building walls, tree crowns have large spatial variation, depending on the orientation, materials, and shading conditions.  

 

Table 5: I regret having to point this out, but as a researcher in micrometeorology, I find it difficult to believe that there is academic value in correlation analysis based on such primitive meteorological observation data. The temperature field in urban spaces changes unsteadily due to radiation, convection, and heat conduction phenomena, and the physical mechanisms behind these changes have already been explained in textbooks published over 50 years ago. 

 

Section 3.2: 

Since Section 2 does not explain how the thermal sensation map shown in Fig. 5 was obtained, it is difficult to assess the scientific reliability or academic significance of this result. Regarding outdoor thermal sensations perceived by pedestrians, previous researchers, through extensive trial and error, have developed scales to evaluate thermal sensation across a wide range of individuals, such as the Thermal Sensation Vote (TSV). In contrast, the color scale in Fig. 5 only includes two indicators, "high" and "low." How were the pedestrians' thermal perceptions quantified and mapped? 

Additionally, the color map covers the entire open space in question, but it seems unlikely that respondents who participated in the interviews walked through the entire area and reported their thermal sensations based on actual physical experience. If this is the case, using impressions of heat or coldness without actual exposure to physical stimuli differs significantly from many established, reliable methods for investigating outdoor thermal sensation. If such conventional methods were deliberately avoided, the rationale and validity for doing so need to be clearly explained.

Author Response

Dear reviewers,

Thank you very much for your comments and recommendations. Our paper benefited a lot from those comments. According, we made some updates.

The table below shows the comments and changes made.

In the paper, the modifications are highlighted with yellow colour.

Best regards,

The authors

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thank you for the clarification. I highly rate your work. After the authors' corrections and clarifications, the article is worthy of publication.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors address my concerns.