A Novel Approach to Estimating the Dose of Ambient Air Pollution during Cycling Commutes from Home to School and Route Optimizations

Round 1

Reviewer 1 Report

While there is widespread acceptance of the health benefits of bicycling, recent research has highlighted that the benefits may be partially offset by the potential adverse health impacts as a result of bicyclists’ exposure to traffic-related air pollution.

The manuscript submitted by Yue (Jason) Gao  et al., was proposed a modeling framework to estimate cycling students’ terrain-based dosage of ambient NO2 during home-school commutes . The approach was further applied to compare the benefit and costs of different route choices and examine exposure justice issue during students’ cycling from home to school in Auckland, New Zealand.

In the literature on the subject, the authors addressed this problem. In this respect, the work is not original. However, the manuscript submitted for evaluation provides new data.

 Comments and suggestions:

 1.     The introduction should emphasize the importance of the results in terms of human health. Line 35-36: Please add literature on health effects due to exposure to NO₂. What severe health issues?

2.     There are no explicit research hypotheses in the manuscript.

3.     Lines 150, 168, 186: Please standardize the multiplication sign in equations: „*” (line 150) „·” (line 168) ; „×” (line186)

4.     Line 187: Explain what "Ew" means in equation 7.

5.     Line 314; 338: Figure 3 and Figure 4: Please standardize the font size in the descriptions of the X and Y axes.

6.     Line 359 – Table 4: Please correct and standardize: "10-80K"; "80k-150k"

7.     Line 359 – Table 4: Why did you highlight by bold "27.11%"?

8.     Lines 80-82; 429-431: The text in these lines is repeated. Remove.

9.     Reference Lines 451-520: References not prepared in accordance with the requirements journal Atmosphere.

10.  The authors did not provide the publication's DOI numbers or the Uniform Resource Locator (URL) in the reference list, consequently making it  difficult to find the quoted publication.

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The study proposed a modelling framework to estimate cycling students’ terrain-based dosage of ambient NO2 during home-school commutes for the first time in Auckland, New Zealand. Results show that most cycling students can find an alternative lowest-dose route; for around 25% of them, a 1% increase in route length was associated with a more than 1% decrease in NO2 dosage. Evidence demonstrates that exposure inequalities existed to some extent during students’ cycling commutes.  The study needs the following comments to incorporate in their study:

i) Introduction: add possible research question(s).

ii) Introduction: add more critical and recent literature and link it with possible research hypotheses of the study.

iii) Results: More critical assessment is required for result interlinkages with the earlier studies.

iv) Conclusions: Add research limitations and future directions at the end, and

v) Conclusions: Add short-term, medium-term, and long-term policy implications.

Author Response

Please see the attachment.

Author Response File: Author Response.docx