Dear authors,

Thank you for carefully revising the manuscript according to the comments from two referees and from myself. The manuscript has been significantly improved and augmented. I think it provides interesting results to the atmospheric science community, especially with the addenda of sections 4.4 and 5. Since I asked for these addenda, I didn’t send the revised manuscript back to the referees but did the 2nd review myself. Please see attached the specific comments and questions below and a few edits in the annotated manuscript.

Olivier Bock

Dear authors,

Thank you for implementing all the major changes and additions suggested in my previous review.
I think this work now brings significant answers to questions about the impact of various processing options on tropospheric parameter estimation, including ZTDs, gradients, and ZTD trends.
The results are well documented and discussed in the manuscript.
I send you back the last version of the manscript with a few corrections to clarify some of the statements.
Please note that in my previous review, there was also an annotated manuscript attached. I think you didn't consider it as almost all corrections/edit were unapplied. I repeated some of them in the new version, but urge you to re-read the previous one as well.
Best regards,
Olivier.

Thank you for the revised manuscript and supplement.
They are accepted for publication.
I guess you should provide a version of the manuscript without track of changes.
Thank you for your contribution to the COST Special Issue.
Best regards,
Olivier BOCK.