Potential Strong Inhibition on Ozone Production Sensitivity by Particle Uptake
Round 1
Reviewer 1 Report
Very nice paper about very important topic, which is seen very rarely! Thank you for your contribution. The English is excellent and the paper is written in clear form with consistency in the text. My major (but minor in general) issue is how did you measured VOCs, which one you measured, what was the frequency of measurements, how the measurements of VOCs was calibrated, what is the measurement setup. Unfortunatelly this is not mentioned in the manuscript, although VOCs are important in the manuscript.
Here are few detailed comments:
line 66: An interesting study might be included here (10.5194/acp-22-5603-2022) showing biogenic VOC emissions measured within a smaller city.
line 205: which VOCs were measured?
lines 205-207: Model 42i-TL measures NOx and in here you mention O3. Please arrange the sentence so that the order of gases measured will fit the order of the analysers. Currently you have NOx, O3 and CO. How do you measure VOCs? What is the frequency of measurements?
Results: please provide here information about the (daily averaged or so) concentrations of O3, NO, NO2 and VOCs. Please specify which VOCs you measured.
discussion: do you assume that the morning sensitivity to VOC could be because the biogenic VOCs likely peak in the central hours of a day? When is the peak of anthropogenic VOCs?
Author Response
Please see the attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
The present manuscript” Potential strong inhibition on ozone production sensitivity by particle uptake” discuss the importance both NOx sinks with particle uptake into account to optimize the observation-based analysis of the radical loss and thus O3 relative production sensitivity. The study was conducted in suburban site in Chun'an, a county in China. Such studies are absolutely necessary in developing O3 pollution control legislations.
Overall comments
· The present work was carried out at the Chun'an, a county in China, how do the authors find their study relevant to the other part of the world?
Author Response
Thanks for your advice. Due to the fact that this field campaign was carried out at Chun'an, a county in China. It is still limited from the spatiotemporal perspective and it is necessary to continuously promote similar field campaigns in other parts, wider coverage and longer duration in future.
Reviewer 3 Report
This manuscript describes an interesting approach and field data to analyze ozone production in a China megacity during March. An „average“ reader of „Atmophere“ is left alone because a lot of the basics are simply not explained or not shown. How large are the concentrtions? What exactly is meant by the term „ozone production sensitivity“? A more specialized reader is also let alone, more or less fot he same reasons: How large are the concentrations, how ist he general setup, what are the uncertainties in concept and data. Overall, this reviewer is left alone with the question: What can we learn from a sensitivity analysis that changes ist outcome every day and eery night? Isn’t al tat diven by radiation? What are potential measured to limit ozone production in that area?
The maucript has a lot of wek points, som of which are listed below. This revieer is not sure i fit can become an acceptable paper for „Atmosphere“ after major revision.
Introduction, first paragraph: Authors introducte into a topic that was studied in Europe and North America some 20 years ago. A huge knowledge basis exists. Authors try to wrap up the general understanding on the sinsitivity of O3 formation within a few lines. This reviewer doubts that most readers will be abe to understand what the „ridge“ (lne 36) in a classical EKMA plot means. Isn’t that a too short intro? Further, this reviewer doubts that the authors do really understand it. The „ridge“ separates conditions that are VOC-limited from those that are NOx-limited. However, the authors are are talking about VOC-sensitivity and NOx-sensitivity in this context. That is a different story. It appears that authors interpret the sensitivities correctly, but this is not at the ridge! Actually, NOx.limitation (conditions when more NOx leads to less O3 production) is a very important issue in heavily polluted, urban air. See also more comments further below.
Line 44: What is „particle uptake“?
Lines 49 – 59: The uptake coefficient needs to be defined when being discussed in detail.
Line 202: Please be much more precise in providing the location, 2 more digits.
Line 205: Much more info concerning the VOC measurement needs to be provided. Which ones were included, detection limits, and more. The same applies for the measurement of particle surface (lines 208 – 209)
Line 239: This reviewer did not go through the entire theoretical derivation of L_N and Q and their ratio L_N/Q. That said, and assuming that a good portion of interested readers might do the same, authors should explain in short words how L_N/Q was obtained, and what the involved uncertainties are. Was equation E33 used? If yes, authors need to explain all variables that went into this computation. What are the assumptions? On what temporal resolution was the computation made? Which parameters are most uncertain, and how large are the uncertainties? Authors need to include unvcertainty ranges into the Figures 2+. Further, this reviewer is still left alone with the „sensitivity“ concept (see comment further above). Where is the transition between positive influence of increasing NOx on O3 formation and negative influence?
Line 258: It seems that authors typed 03 here (zero three) instead of O3 (letter O, three), here ind in later caes as well.
Lines 282 – 288: In a highly polluted situation, when NO increases above zero (here, above 0.2 or 0.4 ppb), there should not be much O3 present, because O3 will react rapidly with NO. That is more or less common understanding. Are such conditions present in the current study? The reader is left alone with fractal informtation, the entire picture is simply not shown. How large are the NO2 concentrations at the same time? It does not suffice to show some info in the supplements.
Line 306 onwards and Fig. 5: Now this reviewer starts to understand what is meant with the sensitiviies. Actualy, limitations are probably meant. Anyway, the systems responds to incresing NOx with decreasing O3 formation, correct? Then, the heading of the y-axes are wrong. The „sensitivity“ towars NOx is always lower than that towards VOC, except in the afternoon, 14 hrs (it is uncear why authors state it otherwise).
Lines 374, 375: This reviewer cannot see that shift, see Fig. 5.
The entire Material and Methods as well as Conclusions sections deal with section deal with the sensititivy analysi of O3 production with respect to VOC and NOx. Almost nothing about particulates. That would be fine if there wasn‘t the title „…ozone production sensitivity by particle uptake“
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
The revised version of this manuscript does not show much of modification in comparison to the previous version. In their letter of response and during revision of the manuscript, authors simply ignored the major points of concern that this reviewer had made (first 3 paragraphs of review). As a result, readers are still left alone. Readers with or without much knowledge about O3 still cannot follow the storyline for various reasons.
The title does not reflect the content of the paper, as said before.
The location is not given with more precision now. Instead, the precision has been reduced.
Author Response
Please see the attachment
Author Response File: Author Response.docx
