The title of the paper is very misleading.  The study done is certainly not comprehensive.  And why “Introducing?”

The abstract is poorly written.  It does not explain what global warming scenario is used.  It does not mention what climate models are used.  It jumps right into SAI while ignoring the fact that it does not exist, and is only a proposed scheme.  It ignores the need to assess a wide range of potential benefits and risks before it is ever implemented.  It does not say what is being injected.  In fact the experiments are injecting gas and not aerosol. 

The scientific questions being addressed by this paper are obscure.  The paper says it wants to examine the response to certain sulfur dioxide emissions with respect to one global warming scenario using one climate model and specified injection altitudes and temperature reduction goal.  It is by no means comprehensive.  But why are they doing it?  Is it a technical exercise for one specific modeling group?  If so, this should be a technical report and not a journal article.  I am not convinced it should be otherwise.

The paper is very long and detailed, going through many variables from the climate model simulations they did.  I lost interest before I got halfway through.  Why would other readers find this interesting?  The paper does not pose interesting scientific questions that are then answered by specific experiments.  I could not find any interesting new science in the paper.  Many of the results are what would be expected.

On line 65 the paper says, “The understanding that comes from the analysis of the differences between these strategies lays the foundation for future work.”  That is what a technical report should be doing, not a journal article which needs new science to justify publication.

In several places, “We note that” is in the text and should be deleted.  Every sentence should be noted or it should not be in the paper.

There are 45 additional comments in the annotated manuscript.  If the authors chose to reply to this review, a response of “we addressed all the comments” would not be sufficient.  Each comment should be listed with a specific response.

The authors present a study of a small set of stratospheric SO2 injection scenarios using a climate model, CESM2(WACCM6-MA). 

Like the other reviewer, I have very serious issues with (1) the way the paper is framed in the context of what work has taken place and been published in the past, and (2) with the lack of detail given with regards to the methods. While the manuscript is long and quite detailed in terms of the analyses presented and the results (perhaps this analysis is the "comprehensive" part, rather than the very small set of injection scenarios investigated?), and there are likely some valuable technical additions to the literature in there that are worth publishing eventually, this is all called into question by these other major issues. Since those issues could be fixed by an extensive re-write I am recommending major revisions rather than rejection.

Claiming that the investigation presented here is "comprehensive," in a way that no previous studies have been, is simply incorrect. The authors present 5 injection strategies. Four of these are actually the same strategy, but with different injection latitudes - so actually only 2 different strategies. This is very much in line with previous similar studies in the literature, including ones that share many of the same co-authors with this paper. So this choice of language is deeply puzzling. Responsible, accurate, and technically rigorous communication is always important in the scientific literature, so I would comment on this in any case, but it is especially critical in areas of intense societal interest such as SAI research. Note that this is not a simple problem that's going to be solved with superficial "find and replace" type wording changes. The whole way the value of the study is presented and what aspects of the study are emphasized needs to be revisited and rewritten.

Far too little information is given on the technical approach. This aspect of the paper reads like an internal report rather than a manuscript for the literature. The other reviewer also commented on this. More information is needed on the model and climate scenario underpinning the simulations.  The authors are surprisingly vague about the "controller(s)" which are used to determine injection rates. Equations and parameters for this technical feature need to be shared - along with some discussion of how this would be implemented in any kind of practical sense.  The authors are directed to another paper for these details - which would not be sufficient even if the reference trail were clear - but it is not at all clear what paper is being referenced here (after 10 minutes searching I did not find a Visioni et al. 2022 with this title).  The other reviewer touched on many more technical issues which must be addressed but which I will not repeat here.

Please see the enclosed PDF for my suggestions and recommandations.