Influence of Natural Tropical Oscillations on Ozone Content and Meridional Circulation in the Boreal Winter Stratosphere

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please find the attached file with the comments and suggestions.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Though a few minor grammatical problems, such missing prepositions, need to be fixed, the writing's language is in decent form. There are few poorly constructed sentences. The authors should take care of those as well.

Author Response

We would like to thank the reviewer for useful comments that help to improve the paper. Our responses are following reviewer queries in the bold in the attached file.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript assesses the changes in ozone content in the stratosphere under four different combinations of ENSO and QBO phases using MERRA2 reanalysis data. The results are interesting and the manuscript is written clearly. However, the robustness of the analysis and discussion of the results can be improved.

 

Major comments:

(1)     Uncertainty of analysis. I recommend the authors evaluate the MERRA2 data uncertainty and how that impacts the analysis. I’m concerned that the current conclusions are drawn from relatively small ozone difference as shown in Figures 2-5, the difference might be heavily impacted by the uncertainty of MERRA2 data. One way could be to run bootstrap to vary the ozone content within the observation uncertainty and see if the conclusions are consistent and robust under these iterations.

(2)     Discussion of the results. (a) The authors stated that it is difficult to compare the results with the literature because QBO is determined by different methods. It is partly true but it is not a convincing reason for not doing the comparison. You can still compare with studies that used similar QBO definition to see if results are consistent, or use other reanalysis products. (b) I recommend the authors adding more implications on how the observed cumulative effect can influence boreal regions, such as local temperature, health, weather, etc.

 

Specific comments:

L24: why aerosol is used as a keyword?

L54: do you mean ozone mass mixing ratio vs concentration? Or dry air? This sentence needs to be clarified.

L87: please provide references for this statement (‘… during a cold phase’)

L221: need to expand some discussion on this to explain why for these areas.

Figures 2-5: (a) probably good to explain how the numbers are calculated in the Method section, the current explanation in the figure legend is confusing (‘the difference between La Nina-EQBO … -contours in November’); (b) missing figure number a,b,c,d in the figures

 

Author Response

We would like to thank the reviewer for useful comments that help to improve the paper. Our responses are following reviewer queries in the bold in the attached file.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

It is not possible to understand your figures. Please explain all numbers and lines in your figures. After this I am able to do  the review. It is only small change, but very important

Author Response

We would like to apologize for the fact that our figures were not clear to the reviewer. 

We have corrected the captions to the figures. We also tried to improve the manuscript in accordance with the comments of other reviewers: we explained the reasons we used MERRA2 reanalysis data and made a comparison with MLS data (prepared additional figures in supplementary file).

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Please find the attached file.

Comments for author File: Comments.pdf

Author Response

R E P L Y to the second review of the paper atmosphere-2954211 “Influence of natural tropical oscillations on ozone content and meridional circulation in the boreal winter stratosphere”. Thank you very much for your remarks and the specific comments regarding our revised manuscript. Your statements and suggestions are very much appreciated. We have considered most of them in the secondly revised version of the paper. Below is our response to the issues raised in the review. Our responses are following reviewer queries in the bold.

 

Second review comments on the manuscript by Ermakova et al.

I am glad to see that the authors have taken serious effort to improve the manuscript as per my comments and suggestions. I feel that this manuscript is in good shape now to be accepted soon after my few last suggestions mentioned below. So, I recommend a minor revision now:

1. Include the RMC plots within the manuscript instead of putting in the supplement and use the red-blue discrete colormap.

We have prepared new figures with the proposed colormap. However, we left them in the file with supplementary material, since in the manuscript the residual meridional circulation is as well shown in figs 3-5 (figs. 2-4 before the second revision). The demonstrated difference between the phases more clearly emphasizes its weakening/strengthening and the heights where this weakening / strengthening is maximum. We do not insist on our version and leave it to the discretion of the guest editor.

 

2. I suggest including the comparative plot of MLS and MERRA2 ozone for the event years in a separate figure with one small section discussing that the reanalysis data matches well with the observations and due to lack of availability for all the study period, the authors have gone for the reanalysis data. They should give some related references too.

We included the comparative plot of MLS and MERRA2 ozone for three different months. The discussion and related references had been added in previous step of revision.

3. Include the reference Nath et al. 2013 where you discuss about the ozone variation in the tropics during ssw in the introduction. They have done an extensive study which will support your work.

Included

4. In the conclusion section, the main findings should be listed at the end for a quick take-away for the readers.

Done

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have successfully addressed my comments. I recommend publication. 

Author Response

Thank you very much for your remarks and the specific comments regarding our revised manuscript. Your statements and suggestions are very much appreciated.