|I’ve been asked to review the revised version of the manuscript for the first time. The aim of this paper is to describe a simple model linking CO2 emissions to ocean acidification and sea level rise; numerous updates have been suggested already in the first round of review. |
I’m not an expert on ice sheet modeling, but I think the first 2 reviewers addressed that part already and the authors followed all of the suggestions and improved the manuscript compared to the fist iteration.
In general, I think that such a fast, simple model would be a pretty interesting addition to the literature. However, the results that the authors obtain for SRM have been already discussed in the literature before: for instance (Zarnetske et al. 2021) talk about the fact that ocean acidification wouldn’t be reduced, and while the land carbon sink might be increased (see for instance Cao and Jiang, 2017), that’s really not by much. It would be good for the authors to acknowledge the work done in this area and say that their results confirm (or not if they don’t) previous findings.
A few general comments:
The paper also deals with SRM but the title does not suggest that: “emissions” is a pretty vague term to include both anthropogenic CO2 emissions and SRM. I suggest to change it to something that actually explains it’s about both.
By the way, the term that is now more widely used for SRM is Solar Radiation Modification and not Management (see NASEM report in 2021) or Sunlight Reflection Methods.
I would suggest at least explaining what SRM is in the introduction - it might not be so widely known as the authors think and a reader can’t be expected to go look at the references provided.
L 12: because of the long
L 14: not sure “value” is the right word here: assessing the efficacy is perhaps a better term
L 79: SO2 is a gas, so “SO2 aerosol injections” is not really a meaningful definition.
L 412: I would remove the square brackets  for the estimates of ECS and TCR.
L 480: “ We have considered that the Solar Radiation Management sulphur injections remain zero during the whole simulation period.” unclear of why it is relevant here. The RCPs and SSPs do not have SRM, and the G6 experiment is another thing and discussed in another section. This phrase is repeated multiple times in the following paragraphs and it really doesn’t need to: maybe say at the beginning of Section 3 when you’ll be considering SRM instead of all the scenarios where you’re not.
Figure 9 (and following figures): it is customary to name the panels in alphabetical order to make it easy on the reader; the legend hides one of the panel’s results.
Fig. 18: The comparison between SURFER results and G6 is interesting, but it could be done in just one plot. If the authors want to contact me (being the author of the 2021 paper cited, email@example.com) I’ll gladly give them the SO2 values to combine the two figures in one.
Cao, L., & Jiang, J. (2017). Simulated effect of carbon cycle feedback on climate response to solar geoengineering. Geophysical Research Letters, 44, 12,484– 12,491. https://doi.org/10.1002/2017GL076546
Potential ecological impacts of climate intervention by reflecting sunlight to cool Earth,
P. L. Zarnetske, J. Gurevitch, J. Franklin, P. M. Groffman, C. S. Harrison, J. J. Hellmann,
Forrest M. Hoffman, S. Kothari, A. Robock, S. Tilmes, D. Visioni, J. Wu, L. Xia, C.
Yang, Proceedings of the National Academy of Sciences Apr 2021, 118 (15) e1921854118;