Enhancement of Cloud-to-Ground Lightning Activity Caused by the Urban Effect: A Case Study in the Beijing Metropolitan Area

Round 1

Reviewer 1 Report

General comment: This paper considers the impact of urban development on lightning activity in the Beijing megacity. An eight-year lightning dataset of cloud to ground (CG) flashes, provided by the National-Wide 15 Lightning Detection Network in China, is analyzed. Compared with the upwind area, the CG flash density in the downtown area enhanced about 50%. Negative CG flashes mainly occurred in the downtown and industrial area, while positive CG flashes distributed evenly. In addition, there is a non-linear relationship between pollutant concentrations and CG flash number, which indicates that there are other critical factors affecting the production of lightning.

Major points:

The description of the Bejing climate, at the end of section 2, while valuable, is rather imprecise. Which is the period considered? How many data were considered for radiosounding and other fields? In addition, the average CAPE values seems quite high. Do you have an explanation for this?

The results in section 3 are presented without a critical discussion. Some explanation of the differences between this work and those of the bibliography referred into the text should be provided.

The discussion of Figure 4 cannot be reviewed because the figure is not correctly represented in the pdf. Figure 4c, referred into the text, is not visible. 

Minor points: There are sticky notes along the attached pdf of the paper where the authors can find the minor corrections to be done.

English editing: In general the English of the paper is fine.There are few sentences that I could not understand. In these cases review the English. 

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Review of Enhancement of cloud-to-ground lightning activity caused by the urban effect: a case study in the Beijing metropolitan area by Wang, Lu, Shi, Ma, Zhu, Liu, Peng, and Wang

This manuscript describes a small study of the lightning flashes in the Beijing, China metropolitan area. Although the study is small and has no major new discoveries, the dearth of studies of lightning in this region warrant the publication of this manuscript, with a few minor changes.

Specific Minor Issues:

1. Lines 80-83: There should be a reference for the lightning network.
2. Figure 2a: The authors should outline the extent of the urban areas of Beijing.
3. Figure 2a: The authors should show the full extent of the lightning density, not just the density in the two small regions.
4. Figure 3a: The authors should outline the extent of the urban areas of Beijing.
5. Figure 3a: The authors should show the full extent of the lightning density, not just the density in the two small regions.
6. Figure 3b: The authors should outline the extent of the urban areas of Beijing.
7. Figure 3b: The authors should show the full extent of the lightning density, not just the density in the two small regions.
8. Figure 4: The whole figure needs to be on the page.
9. Figure 4c: I don’t see a figure 4c at all.
10. Line 252: Separate out the discussion and conclusion sections.
11. Figure 5a: Either get data that shows the aerosol index over the study area or eliminate that data (and it’s discussion) from the paper completely.

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

This paper investigates the possible impact of urban development on lightning activity in the metropolitan area of Beijing, an eight-year (2010-2017) cloud-to-ground (CG) lightning based on the dataset provided by the National-Wide Lightning Detection Network in China. The paper is short, lacking of appropriate references to techniques and methodology. The methods are also poorly described preventing reviewer of following the paper.
Authors should re-write the methodology section, providing more details in the introduction section (references), describing in an appropriate way (details and references) the instruments that they used, the techniques and any other methodology referred in the paper.

The relevant meteorological maps and satellite images related to UVAI and AOD for the case study period would help to support the conclusions.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors have considered all my comments and adjusted the paper satisfactorily.

Please note just the following two points:

1) I would put a "(not shown)" at the end of line 257.

2) the conclusion at lines 367-368 "

The percentage of negative CG lightning with Ipeak ≥75 kA is more than 6 times of positive CG flashes." 

seems incorrect, and should be reversed (i.e. the percentage of positive flashes is more than 6 times the negative flashes).

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

The revised paper is carefully prepared, the authors taking into account the suggestions given in the previous review. Also, the methodology and results are well written and structured. I recommend this article for publishing.

Author Response

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Author Response File: Author Response.docx

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.