Urban Canyon in the CBD of Rio de Janeiro (Brazil): Thermal Profile of Avenida Rio Branco during Summer

Round 1

Reviewer 1 Report

Review: Urban canyon in the CBD of Rio de Janeiro (Brazil): Thermal propfile of Avenida Rio Branco during summer

The new version of the manuscript is almost the same as its first edition. The reviewing process is difficult because line numbering of the manuscript is missing. Answers of the authors to the reviewer comments and recommendations are missing. In my opinion, there are still major items that should be considered before publishing.

1. The abstract starts with the statement „This study aims to evaluate the land surface temperature (LST) and the thermal characteristics ……. “ Analytical description or comments about the correspondence between these two parameters are missing?
2. In the ‘Results and Discussion‘ authors start with the statement „Initially, the land surface temperature measurement was used to understand the thermal field of the CBD. Afterwards, explanations about the link between LST and the thermal characteristics UCL are needed
3. What is “TST“ on Figure 3?
4. The titles of sections 3.1, 3.2.are not adequate and informative.
5. In Section 3.2.1 it should be explained the way in which the authors classify the atmosphere for stability/instability using Web-Based Atmospheric Correction Tool for Single Thermal Band Instruments [21]. Otherwise the reader waits for some quantitative assessments based on meteorological parameters (instability indexes, CAPE).
6. 2.1., the phrase “The hPa remained constant until 1 pm at 1013mb” should be replace by “The air pressure remained constant until 1 pm at 1013mb”
7. In ‘Results and Discussion‘ the authors have not considered some basic recommendations, or at least to try answer to the reviewer’s suggestion, i.e. some analytical comments on the results to be presented. I would repeat some of these suggestions:

• Regarding authors’ comments for Figure 3: ‘These differences are associated with the vegetation potential to lower the thermal load, the covering of land by buildings, and the roughness of the urban morphology.’’, ………... it makes sense to explain the mechanism for making vegetation a factor to lower the thermal load; you may find explanation on this mecahnism for example in the following paper (or in other relevant):

Stoyanova, J.; Georgiev, C.; Neytchev, P.; Kulishev, A. Spatial-Temporal Variability of Land Surface Dry Anomalies in Climatic Aspect: Biogeophysical Insight by Meteosat Observations and SVAT Modeling. Atmosphere 2019, 10, 636. https://doi.org/10.3390/atmos10100636

• Results in 3.1. are performed on a qualitative basis, actually no physical analyses are performed.
• The physical chain of energy transfer and to bridge the time gap between day and night are important; practically no any analyses here, conclusions linking day-time and night-time processes are missing.
• I would recommend authors to gain more deep knowledge using for example analyses by: Parlow, Eberhard, Roland Vogt and Christian Feigenwinter 2014: The urban heat island of Basel – seen from different perspectives. – DIE ERDE 145 (1-2): 96-110, DOI: 10.12854/erde-145-8, where it is well shown that Urban Heat Islands vary essentially with the choice of the respective temperature (LST, air temperature) and height (surface level, street/canopy level, roof level).

8. In the Conclusion the authors say ‘……the proximity between the buildings that make up the urban canyon is responsible for creating niches of lower LSTs.‘ It have to be indicated that this conclusion is based on visual comparisons of LST.
9. It is not a good practice to present graphs in the Conclusion. It is better Fig.15 to be transferred in the Result and Discussion.

 

Author Response

The new version of the manuscript is almost the same as its first edition. The reviewing process is difficult because line numbering of the manuscript is missing. Answers of the authors to the reviewer comments and recommendations are missing. In my opinion, there are still major items that should be considered before publishing.

A: We forward detailed responses to all reviewers' suggestions and comments, including those we don't agree with, we're sorry if for some reason the reviewer didn't have access, but it wasn't our fault. And once again, regarding line numbering, this is not an editorial requirement, so it was not included.

1. The abstract starts with the statement „This study aims to evaluate the land surface temperature (LST) and the thermal characteristics ……. “ Analytical description or comments about the correspondence between these two parameters are missing?

 

A: We don't believe it's missing, we mobilized two techniques to understand the phenomenon and they presented divergent results for what interests us: the urban canyon, as shown in the fragment below. We made changes for a better understanding of the proposal and indicated the divergent relationship between the techniques, more details than that, it is up to the reader to seek in the detailed analysis presented in the article.

1. In the ‘Results and Discussion‘ authors start with the statement „Initially, the land surface temperature measurement was used to understand the thermal field of the CBD. Afterwards, explanations about the link between LST and the thermal characteristics UCL are needed

A: We chose, to avoid confusion, to withdraw this statement and enter the analysis based on the techniques used.

 

 

1. What is “TST“ on Figure 3?

 

A: Done.

 

 

1. The titles of sections 3.1, 3.2.are not adequate and informative.

 

A: This is a very private issue and we do not agree with the comment, however there was an effort and we modified it to improve the titles.

 

1. In Section 3.2.1 it should be explained the way in which the authors classify the atmosphere for stability/instability using Web-Based Atmospheric Correction Tool for Single Thermal Band Instruments [21]. Otherwise the reader waits for some quantitative assessments based on meteorological parameters (instability indexes, CAPE).

A: Done.

 

 

1. 2.1., the phrase “The hPa remained constant until 1 pm at 1013mb” should be replace by “The air pressure remained constant until 1 pm at 1013mb”

 

A: Done.

 

1. In ‘Results and Discussion‘ the authors have not considered some basic recommendations, or at least to try answer to the reviewer’s suggestion, i.e. some analytical comments on the results to be presented. I would repeat some of these suggestions:

 

A: We believe that the references already mobilized fulfilled this function, however, as the evaluator is so keen on citations, we incorporated them into the text.

 

• Regarding authors’ comments for Figure 3: ‘These differences are associated with the vegetation potential to lower the thermal load, the covering of land by buildings, and the roughness of the urban morphology.’’, ………... it makes sense to explain the mechanism for making vegetation a factor to lower the thermal load; you may find explanation on this mecahnism for example in the following paper (or in other relevant):

Stoyanova, J.; Georgiev, C.; Neytchev, P.; Kulishev, A. Spatial-Temporal Variability of Land Surface Dry Anomalies in Climatic Aspect: Biogeophysical Insight by Meteosat Observations and SVAT Modeling. Atmosphere 2019, 10, 636. https://doi.org/10.3390/atmos10100636

A: As a tip, the following article brings the same contribution and in more detail:

Zhang, Y. Land surface temperature retrieval from CBERS-02 IRMSS thermal infrared data and its applications in quantitative analysis of urban heat island effect. J. Remote Sens, 2006, 10, pp. 789–797. DOI: 10.12691/jap-4-1-3

 

• Results in 3.1. are performed on a qualitative basis, actually no physical analyses are performed.

A: As stated, the article does not propose a detailed analysis of the processes associated with the generation of surface thermography, it is not a methodological discussion, we start from the literature to demonstrate the relationship of the thermal field with urban forms and functions, and not to detail such processes.

 

The physical chain of energy transfer and to bridge the time gap between day and night are important; practically no any analyses here, conclusions linking day-time and night-time processes are missing.

• I would recommend authors to gain more deep knowledge using for example analyses by: Parlow, Eberhard, Roland Vogt and Christian Feigenwinter 2014: The urban heat island of Basel – seen from different perspectives. – DIE ERDE 145 (1-2): 96-110, DOI: 10.12854/erde-145-8, where it is well shown that Urban Heat Islands vary essentially with the choice of the respective temperature (LST, air temperature) and height (surface level, street/canopy level, roof level).

A: given great insistence, we used the mentioned article, however, the differences in sites and factors lead to divergences between the results.

1. In the Conclusion the authors say ‘……the proximity between the buildings that make up the urban canyon is responsible for creating niches of lower LSTs.‘ It have to be indicated that this conclusion is based on visual comparisons of LST.

A: Done.

1. It is not a good practice to present graphs in the Conclusion. It is better Fig.15 to be transferred in the Result and Discussion.

A: Done.

 

Reviewer 2 Report

The present work regards the understanding of the intensity and development of the urban heat island in a particularly complex area such as the Central Business Distric of Rio de Janeiro. The scientific interest on the subject is high so I think it is a theme of relevance. The authors responded to the comments I made earlier in the first submisison. I believe it is now ready for publication.

Author Response

None to replay

Round 2

Reviewer 1 Report

Authors have made efforts to improve the manuscript and I think they succeed in this. Some additional physical explanations are included that much contribute the work. Hope they have gained a good experience working on  improvement of the manuscript but this is also important for the Journal in general. In this latest version the manuscript can be published.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

As a general comment I would start with the conclusion that this is a carelessly elaborated manuscript. This study is aimed to evaluate the formation of surface heat island over of the urban canyon in Avenida Rio Branco in Rio de Janeiro according to the manuscript, but the title is not related to this context. It is understandable that the problem of heat island is of importance for the studied region but the analyses should be convincing using contemporary methods. All materials are presented by the authors on a descriptive level, not supported with corresponding quantitative illustration, evaluation, analyses. Authors say that the land surface temperature (LST) from TIRS sensor acquired on the USGS website and the thermal characteristics of the Urban Canopy Layer (UCL) will be used but actually all analyses are subsequently performed on the bases of air temperature, Tair following the presented Figures. Using Tair for analyses of urban heat island is the first methodology arised still in early 1833 (by Howard) for these types of studies; there are no comments of recent methodologies applied nowadays related with the energy/heat balance of the surface. It is rather questionable the statement ‚‘‘…however, the satellite data and the data collected during the ten days of field experiments diverged‘‘. The data set used for the analyses from field experiments is too small, only 10 days in 2021. At these circumstances, how do the authors manage to make the conclusions?

The study is not good performed, it needs to be given further meaning of the work; it is not relevant structured and motivated, analytical discussion is almost missing in the main text as well as in the conclusion. In this form the manuscript cannot be accepted for publishing, the work needs of a major revision and further elaboration before consideration for the next application in Atmosphere.

Specific comments:

1. Line numbering of the manuscript is missing that makes some difficulties to allocate exactly the suggestions/comments.
2. The title of the manuscript is not relevant, in no way it could be understand what kind of problem concerns the work?
3. The Abstract is not good balanced and there are no precised statements:

– ‘In order to conduct this evaluation, two methods were employed: 1) summer LST estimation from the last….’ Please correct, you should first introduce the method used for LST estimation, this is absent.

• ‘The CBD showed extensive areas with surface heat islands….’. Please correct the text , the CDB can’t show anything, it might be characterized by…..

4. Introduction: there are no any analyses about the contemporary methods used to identify heat islands?
5. Materials and Methods is not good structured and a lot of uncertainties are seen, for example:

• Not adequate title of paragraphs 2.1 and 2.2.1
• ‘……1) summer LST estimation from the last decade…’. Again is missing to describe how LST is estimated?
• For LST dataset the period 2011-2020 is indicated in the sub-title, while indicating the selected images in the text the period of 2014-2019 is covered?
• Some explanations for Figure 2 related to the specificity of location of measurement points is relevant to be given to facilitate the understanding the infrastructure influences not only visually.

6. Results and Discussion

• Authors indicate two different paragraphs in manuscript with the same 3.1 numbering?
• Regarding authors’ comments for Figure 3: ‘’These differences are associated with the vegetation potential to lower the thermal load’’, ………... it makes sense to explain why vegetation can lower the thermal load; you may find explanation on this problem for example in following paper:

Stoyanova, J.; Georgiev, C.; Neytchev, P.; Kulishev, A. Spatial-Temporal Variability of Land Surface Dry Anomalies in Climatic Aspect: Biogeophysical Insight by Meteosat Observations and SVAT Modeling. Atmosphere 2019, 10, 636. https://doi.org/10.3390/atmos10100636

• Do you really need to show Figure 4?
• Results in 3.1. Paragraph are performed on a qualitative basis, actually no more deep analyses is performed.
• 1.1, 3.1.2, and 3.1.3 focus on field experiments at different synoptic situations bases of Tair. It makes impression that situations are simply described without more serious physical analyses and interpretation of processe.
• Two separate analyses using LST from TIRS sensor and from field measurements of Tair are performed, but no intercomparasion is given?
• The physical chain of energy transfer and to bridge the time gap between day and night are important; practically here anymore deep analyses, conclusions linking day-time and night-time processes are missing.
• I would recommend authors to gain more deep knowledge using for example analyses by: Parlow, Eberhard, Roland Vogt and Christian Feigenwinter 2014: The urban heat island of Basel – seen from different perspectives. – DIE ERDE 145 (1-2): 96-110, DOI: 10.12854/erde-145-8, where it is well shown that Urban Heat Islands vary essentially with the choice of the respective temperature (LST, air temperature) and height (surface level, street/canopy level, roof level).

Reviewer 2 Report

The present work is aimed to study the urban heat island in an urban canyon in Avenida Rio Branco in the Central Business District (CBD) of Rio de Janeiro during summer. Different weather conditions have been considered: stability (high pressure), instability (low pressure) and afert instability.

The paper is not clear, several distraction errors are present, and it is difficult to read. Moreover, some choices of authors in defining heat island magnitude, in the presentation of the results and in the results obtained they are not in agreement with my thinking.

Following my point by point comments:

 Abstract: niches : cool spot?

Par 2.1 pag 2: you have images from 2014 to 2019 so the considered period is 2014-2019 not (2011-2020)

Par 2.2.1 pag 5: their rebound on the thermal field.  Effects?

Par 2.2.1 pag 5: Specifically, the air temperature values from the airport weather station served as the basis for subtracting and identifying the heat island intensity: usually the heat island intensity is computed considering a rural weather station. It seems not the case in this paper. The airport has a LST value same to the city one and it seem not so close to a rural site.

 Par 3.1 Pag 6: Using the 2018 Land Use and Occupation Law (Figure 4) and LANDSAT-8 images, it was possible to observe that Campo de Santana, a "green island" embedded in the Central Consolidated Zone (CCZ), The abbreviation does not correspond to Figure 4 legend: it is difficult to understand which class you refer to.

3.1. Summer Field Experiment (2021) pag 8

Pheraps it is 3.2

Par 3.1.1.: Pag 8 an open sky. This process favored synoptic conditions characterized by open sky, calm weather, and absence of clouds.

Change open sky in clear sky e delete absence of cloud

Figure 6: it is not possible that the mean air temperature is equal to the minimum air temperature. Something is not clear in this graph, it is better show the mean air temperature and the maximum and minimum value of the day not of the hour.

The winds predominated between 7 am and 8 pm, with speeds ranging between 0.4 and 1.8 m/s (east, west, south, and southeast): predominated all these wind directions? Predominate only one usually

Pag 11 Last Par: …were not related to the hottest day recorded bythe weather station, Jan 31, but to Jan 25, a  Monday (Figure 12): Figure 12 is not of 22 Feb?

However, the thermal inversion occurred at night, when the air temperature recorded at the maximum altitude (28,5°C) was 2,3°C above: point not comma between decimal numbers

Pag 14: heating rate: please define how you compute it

Figure 11: same as Figure 6

Pag 15: On Mar 7, in the morning, there was a decrease in temperatures from the ground (24.8°C) up to 50 meters (23.9°C). I think it miss the figure of Mar 7

Figure 14: same as Figure 6 and it misses caption

Figure 16: in y axis it is an anomaly in temperature?