This work focuses primarily on the TEM decomposition following the 1991 Pinatubo eruption to identify drivers of changes in NH polar vortex and, to a lesser extent, the tropical QBO. The results clearly show differences in seasonal drivers of the vortex response, with the summer time response also receiving attention. This paper represents a useful addition to current understanding of these processes and fits well within the scope of the journal.

The manuscript is exceptionally well written, with clear methods, a good introduction and logical journey through the paper. The work is placed well in the context of previous literature. In my opinion, the limitations and conclusions of this study are accurately represented and there are very few improvements I can suggest.

Minor comments:

There is a limitation of only using a single model in this analysis. Are there any posible implications in your results from having a slightly weaker QBO with a phase lock?

L304: 'Most of' the declining QBO strength over the simulation can be explained by ensemble spread - so there is a part which cannot be explained? 

L361 among other locations: This response looks insignificant to me. What do you interpret as less significant or more significant? (also a typo in the word 'response')

Review for ‘volcanic aerosol modification of the stratospheric circulation in E3SMv2 Part 1: wave mean flow interaction’ by Hollowed et al.

This work uses E3SMv2-SPA model to study the dynamics response of the stratospheric circulation to the Pinatubo volcanic eruption, by comparing 15 ensemble members that include the volcanic forcing, and 15 control members. The work is very well written, and the analysis are very thorough and clear. I enjoyed reading this paper and didn’t find much flaw from it. I recommend accepting this work after addressing the following minor suggestions:

1. Sample size. As the authors pointed out, the sample size is very important to simulate the stratospheric dynamics response to the volcanic eruption, because of the internal variability. I like the figures 5&10, where it clearly showed the statistics of two ensembles. I think a 15-ensemble member for the westerly jet response is enough, but QBO could be more complex. I recommend adding a Monte Carlo test on the sample size, say, by randomly picking up different sample size, to check if the response is still robust.
2. In the recent eruption of the Hunga volcano, an equatorward shift of the jet is also observed, during austral winter. It may worth mentioning in the introduction.
3. Line 115 “vertical and horizontal”: to be more specific, meridional.