Dear authors,

the review received on the revised version of your paper was very positive. The reviewer had two minor comments regarding your paper that I ask you to consider in the final version of your manuscript:
1) I think the authors have presented a through revision of their paper and have taken into account the comments by the reviewers very well. I therefore recommend accepting the paper for publication in ACP.

Just one remark:

Regarding the conversion of SO2 to sulphate in the Nabro plume it might be helpful to have a reference to a study regarding the chemistry of the conversion of SO2 by reaction with OH (under conditions of the UTLS, i.e. basically an estimate of OH concentrations) rather than the somewhat indirect evidence from the OSIRIS observations.
2) Update the reference of Ploeger et al: Citation: Ploeger, F., Gottschling, C., Griessbach, S., Grooß, J.-U., Guenther, G., Konopka, P., Müller, R., Riese, M., Stroh, F., Tao, M., Ungermann, J., Vogel, B., and von Hobe, M.: A potential vorticity-based determination of the transport barrier in the Asian summer monsoon anticyclone, Atmos. Chem. Phys., 15, 13145-13159, doi:10.5194/acp-15-13145-2015, 2015.

End of reviewer comments

Please submit a final version of your paper including proper consideration of the above comments at your earliest convenience.

Kind regards,
Gabriele Stiller