The Energy Model of Urban Heat Island
Round 1
Reviewer 1 Report
This study aimed to develop an energy model of UHI based on the difference in radiation fluxes of different nature in the city and countryside. The deductions of equations are presented and further validated by field measurement data. However, the flowing concerns should be addressed.
- The current literature review in the Introduction is not sufficient to support the innovation of this study. Many relevant models have been proposed previously, such as Urban Canopy Models and CTTC models. A more comprehensive literature review should be presented in the Introduction to introduce the basis of this study. The existing research gaps should be further highlighted based on the reviewed literature to support the value of this study.
- How were the effects of 3D urban geometry considered in the proposed model? The geometry of the street canyon can provide shadings, cause multiple reflections and impede heat dissipation by longwave radiation. According to Section 2, it may be unclear whether these effects were contained in the proposed UHI model.
- Section 3 presents the testing of the model against the direct measurement of heat islands in Tomsk. It is better to give a picture to illustrate the location of measurement points. A broken line graph may be added to illustrate the comparison between the temporal variation of measured UHI intensities and simulated UHI intensities.
- Discussions of the results of this study should be supplemented below Section 3. For example, features of the energy model of UHI in this article can be further emphasized by being compared with the previous models. Meanwhile, as the contributions of different factors of UHI have been proposed in Line 474 to Lin 482, its inspiration for UHI mitigation can be further discussed in the part of the Discussion.
Author Response
См вложение
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments on atmosphere-1554149
“The Energy Model of Urban Heat Island”
To authors
General questions
How did authors define Summer and Winter? In Russia, the Wintertime should be longer.
What are the inputs and outputs of the model?
How well the model performance is while compared with measurements? I did not find the comparison of measurements with model results.
Measurements are for specific time or date, while model simulations are monthly average. They are not comparable. Does the model have the capacity to read in meteorological data on certain date and simulate UHI? Then compare with mobile station measurements.
The authors listed all the components used to calculate UHI. How is each component calculated? What are the inputs needed for computing each component?
This model can calculate UHI under various meteorological conditions. What about cloudy conditions? How to take different cloud types into account?
Is this model calculating UHI online or offline?
The explanation of each figure is comprehensive. Try to explain more. For instance,
Figure 2. Explain more about the increases in March and Summer.
Figure 6.
1) DQHUHI influences DTUHI most.
2) DQsurSR is inverse proportional to DQHUHI. Explain it.
3) Others are close to 0.0.
4) DT is lower in Summer and higher in Winter. Why?
5) Explain the increases in March and Summer.
Is this model publicly available? If yes, where can the public download it?
Specific questions
Abstract
- Introduction
P1L31: references needed.
P1L33-35: “In this case, the higher the UHI intensity, the more stable the local circulation and the stronger the urban air pollution.” Why? And references
P2L75-76: “since it was found that in the countryside the hidden heat flux for water evaporation QE is much larger.” Why?
- Model of urban heat island
2.1 Absorption of the shortwave and longwave radiation by the underlying surface
P4L144-145: How did the authors derive eq (6) and (7)? Explain it.
2.2. Estimation of atmospheric absorption of the sort-wave and longwave radiation
P4L148: “sort-wave” to “shortwave”
P5L174-177: This sentence is too long and difficult to understand. Rephrase it.
P5L205-206: Are these assumptions reasonable? Explain it.
2.3. Estimation of the effect of absent energy consumption for water evaporation in the city (ΔQE) on formation of the urban heat island
P5L211-213: “One of the most significant factors forming the urban heat island, according to many authors, is the decreased energy consumed for evaporation of water in the city as compared to the background area.” Why? Explain it.
2.4. Anthropogenic heat flux
P6L223-225: It is very interesting to consider human influences in this model.
P6L233: “The error of this approach obviously does not exceed 10%.” How did authors estimate this error?
2.5. Turbulent heat flux
2.6. Calculation of the UHI intensity
P7L292-294: The authors haven’t shown any model evaluation results. Remove this sentence or put it in the conclusion session.
- Testing of the model against direct measurements of heat island in Tomsk as an example
P8L313-319: How to select the background air temperature, humidity? Be careful
P9L353: Figure 2. Why DQsurSR is so large in March? Since this is the average of 1995-2006,
Which year contributes the most and why? Is this consistent for each year?
3.1. Estimation of heat fluxes from measurements of meteorological parameters
P8L321-328: List these measurement data sets in table, including data source, measured variables, availability, etc.
Add session numbers to P8L329, P9L360, 371,
P9L365-366: Figure 3. Add more analysis. Why January is so high?
P9366-367: How did authors get this conclusion?
P10L380-381: “[Error! Reference source not found.]”
P10L384: Table 2. Why ΔQWSR in Table 2 is much smaller than Figure 2?
P11L414: Figure 4. Why did authors select 2004 to conduct experiments? How much difference between 2004 and the average of 1993-2006?
P11L448: Figure 5. Why did authors compare 2004 and 2005?
3.2. Relation between the factors of UHI formation in Tomsk
P12L459: Table 5. What is “∑ ”?
P13L463-464: “It is important to note that if the turbulent heat outflow is not taken into account, then the Matveev equation gives strongly overestimated values.” Why?
- Conclusions
Author Response
Please see the attachment
Author Response File: Author Response.docx
Reviewer 3 Report
The topics dealt with the proposed work is very interesting. On the other hand, from the scientific "writing" point of view there are some issues that need to be solved.
Abstract
The Abstract immediately start describing the used approach. On the other hand the Abstract should include ad least the following content:
An introduction of the problem,
the importance of the problem for the related literature,
The drawbacks of the related literature,
The goal of the paper,
The novelty of the paper,
The proposed approach.
Introduction
The literature review should be extended.
To provide an example the Authors states “It should be noted that the relative contribution of each of these factors to the formation of UHI is currently not unambiguously determined.”
On the contrary there are different studies investigating the contribution of these factors. To provide an example some authors quantified the influence of parameters affecting the UHII during the Summer season in urban districts. https://www.nature.com/articles/s41598-020-75018-4. This last is a holistic approach based on both qualitative and quantitative parameters.
The authors should perform an effective review and classification of the existing method in order emphasise the novelty of the proposed approach.
- Model of urban heat island
Since the literature review is not exhaustive, it is not clear if the model of Figure 1 is a proposal of the authors, is modified starting from the literature or is only reported from the literature and is not included in the novelty of the work.
- Testing of the model against direct measurements of heat island in Tomsk as an example
The Section 3 is not clear. It would be useful to include a summary table with all the data acquired by spcifying the use of the data to evaluate every single flux. In addition, another summary table should include the evaluation of heat fluxes from measurements of meteorological parameters (all the heat fluxes of equation 1 and related other equations).
In this way it would be possible to provide the reader with a complete overview of the application of the approach.
It would be necessary to include a qualitative discussion of the proposed approach versus existing approaches to emphasise the novelty.
Conclusion need to be better described. In particular lines 484 - 489 should summarise the performed work.
Again novelty and advantages of using the proposed approach should be commented.
Minor issues
Line 388 (software error, Missing citation)
Author Response
Please see the attachment
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The paper has been improved. Most of the reviewers' comments have been adequately addressed. Some newly published works on Building and Environment and other journals regarding urban heat island and urban thermal environment should be referenced.Author Response
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Comments and Suggestions for Authors
The paper has been improved. Most of the reviewers' comments have been adequately addressed. Some newly published works on Building and Environment and other journals regarding urban heat island and urban thermal environment should be referenced.
Response: Thank you very much for your valuable advice on our article. Links to new articles added [16, 17].
Reviewer 2 Report
To authors
Minor errors
P9L343: Table 1, “Annual statistics data” to “Annual statistical data”
P6L263: “UHI intensity” to “UHII”, same to the following ones, since UHII is defined in page 1, introduction section.
P14L489-490: “Unfortunately, we failed to explain the discrepancy observed on February 11, 2010, within the framework of the proposed approach.” Possible reasons?
Author Response
Thank you very much for your valuable advice on our article.
P9L343: Table 1, “Annual statistics data” to “Annual statistical data”
Response: Corrected
P6L263: “UHI intensity” to “UHII”, same to the following ones, since UHII is defined in page 1, introduction section.
Response: Corrected in all text
P14L489-490: “Unfortunately, we failed to explain the discrepancy observed on February 11, 2010, within the framework of the proposed approach.” Possible reasons?
Response: Unfortunately, we were not able to accurately determine the reason for the model value and direct measurements discrepancy observed on February 11. Perhaps this was due to the wrong choice of the background region in this particular case. However, since the same methodology was used for all measurements, we decided that it was unacceptable to correct the data in one single case.
Reviewer 3 Report
The paper has been improved, however there are still some minor changes in the abstract that need to be carried out as previously requested.
In particular, the abstract need to be improved by including:
1) An introduction of the problem,
2)The drawbacks of the related literature,
3)The novelty of the paper,
The other Reviewer's requests were satisfied.
Author Response
Thank you very much for your valuable advice on our article.
The paper has been improved, however there are still some minor changes in the abstract that need to be carried out as previously requested.
In particular, the abstract need to be improved by including:
1) An introduction of the problem,
2)The drawbacks of the related literature,
3)The novelty of the paper,
The other Reviewer's requests were satisfied.
Response: The abstract has been corrected in accordance with the rules of the journal and your recommendations.