The manuscript for Pallotta  et al. provides an overview of a processing chain which was developed for the South American lidar Network. The developments are based on open science and are all available on github, which is very honourable and I really appreciate the efforts and work the authors have made.

However, I have strong doubts that the current manuscript fulfils the requirements for a research article and is thus appropriate for this journal. It is currently more a technical report, which, however, is not a valid manuscript type within this journal. The reasons are the following:

1. The is nothing scientifically new in this manuscript as the authors use existing approaches to homogenise the different hardware of the lidars in South America in terms of data analysis
2. Mostly, there are  pure technical descriptions which are not relevant for a research article reader
3. On the other hand, the current manuscript is incomplete in terms of methodology description (e.g., how to determine the reference height and value, how does the feature mask really work
4. Most of this missing information might be available on github, BUT I have to judge the current manuscript and the information stored on github are not persistent. I.e., just today I went to the repository and see that the most recent changes are only some days back, while the manuscript was submitted weeks ago.
5. Many of the action items listed in the outlook have also been already published by other groups for other processing chains but are not yet referenced. Thus, the paper lacks also a kind of more complete literature review.

Therefore, I propose the following: The authors should publish their Lidar Processing Chain Code and Description as it is on github via some platform which allow to issue DOI. For example, zenodo can be used for this.

Then, they either use this published code as publication only with the current draft manuscript as introductory comment and skip the publication of a manuscript in this journal

Or, after also having published the code and description with a DOI, they revise the current manuscript in a way, that it can be a research paper. For this, the scientific methods should be more intensively described, and differences to other processing chains (e.g. SCC, PollyNET, Ad-Net..) need to be highlighted. Furthermore, the used methods need to be referenced or, if new, described. Of particular interest would be, e.g., how dead time correction is done  (if done), how the reference value and height for the Fernald method is determined, how exactly the background subtraction is performed …

Furthermore, in the introduction or an own section, the possible differences of different lidar systems should be more detailed described (e.g., analog detection vs. photon counting, pre-trigger vs. far-range background, scanning vs. stare mode etc.). Only by doing so, the reader which is not (yet) a complete Lidar expert can understand the need for this chain and why some variables might be needed and what they mean.

 Beside this. some minor language editing would be needed.

I again have to say, that I  really appreciate the efforts and work the authors have done, but as a reviewer, I have to judge in this case a manuscript submitted as a research article which in my opinion the current manuscript is not.

General comments

The authors illustrated a set of tools aimed to develop a Lidar Processing Pipeline in a collaborative way according to an open-science approach. The processing chain is described and two case studies are illustrated in the manuscript. The LPP approach has certainly a scientific interest for an operative workflow aimed to process Lidar data.  

However, the research gaps the authors are willing to fill is not clear to me, and a description of novel aspects of the work is needed in the Introduction.

Moreover, the introduction should include a state of the art of the topic from scientific literature. E.g. see Reagan et al., 1989; Dang et al., 2019; Wang & Menenti, 2021.

Finally, it is difficult to assess the quality of the results of the case studies without any comparison with different approaches or measurements. No quantitative or qualitative assessment has been done.  I understand that is not easy to set up a quantitative comparative assessment, however, the authors should discuss this limitation and propose future actions to overcome it in the Future roadmap/Conclusion Section.

Minor comments

Lidar technology can have multiple applications, but the authors focused their attention to clouds and aerosols measurements. Therefore, the Title of the manuscript should be more specific referring to the applications of their LPP approach.

Page 2, Lines 50-51. Page 4, lines 72-73. Page 7, lines 107-108. Page 8 Lines 143.145. Page 10, lines 167-169.  Information on the future versions of the LPP should be moved to the Future Roadmaps section.

Page 13 and following. The RESULTS AND DISCUSSION session includes the description of the case studies. A new Section called “Case studies” should be created before Section 3 in order to separate results from case studies description.

References

Dang, R., Yang, Y., Hu, X. M., Wang, Z., & Zhang, S. (2019). A review of techniques for diagnosing the atmospheric boundary layer height (ABLH) using aerosol lidar data. Remote Sensing, 11(13), 1590.

Reagan, J. A., McCormick, M. P., & Spinhirne, J. D. (1989). Lidar sensing of aerosols and clouds in the troposphere and stratosphere. Proceedings of the IEEE, 77(3), 433-448.

Wang, Z., & Menenti, M. (2021). Challenges and opportunities in Lidar remote sensing. Frontiers in Remote Sensing, 2, 641723.