|Review of the revised version of Brief Communication: "Reduction of the future Greenland ice sheet surface melt with the help of solar geoengineering" by Xavier Fettweis et al.|
I happy to see that the authors have used my comments to improve the manuscript. I have some minor comments. My apologies if these comments might seem tangent to the comments on the first version – every time one dives in a manuscript, one finds different points that raise concern.
The line numbers refer the revised version without track changes.
L84: This sentence is a bit longish. “Therefore, we compare MAR forced by CNRM-ESM-1 with MAR forced by ERA5 reanalysis, which serves as reference, for the current climate (1981-2010).
L85: While I still believe one could be more stringent on assessing significant biases, an one sigma margin (this version) is much better than a two sigma margin (previous version).
L89: “Otherwise”? I would say “Furthermore”.
L108: Thanks for this extra section. However, the last concluding sentence (108-111) is hard to grasp as it contains apparently conflicting information. Please simplify this sentence to make your point clearer.
L124-142: Several dots and spaces after sentences are missing, please correct.
L132: “However, if we …” is IMHO better English.
L144: This sentence seems to be inconsistent, please correct. I think you would like to say that ssp245 and ssp585 behave similar, and G6solar somewhat different.
L185: There is no figure in the manuscript that shows that the SMB becomes negative. Neither it is discussed elsewhere in this manuscript. This must be solved in the results section. I acknowledge the importance of the SMB=0 threshold, so simply leaving out this comment (the easiest way to go) is not my preferred direction. (Nonetheless, as since the GrIS topography for which “SMB=0” more or less equals to “MB=0” is that much different to the current topography, I don’t take for granted that a “SMB=0” on the current topography leads for sure to a ~”SMB=0” on the “no-discharge” topography. Nonetheless, it is an important indicator demonstrating that the GrIS is in deep, deep trouble).
Personally, I would end the manuscript with the main conclusion (L187-192) and not with a discussion on the uncertainties on the results. Moreover, this new discussion (L193-196) is actually and officially not allowed in a pure conclusion section as the section is now. Hence, this discussion should be added to section 3 (results and discussion). Therefore, please consider restructuring of the summary to point out the main conclusions more clearly; strongly summarize the discussion on the induced uncertainty by the one-RCM+GCM approach in this conclusions; and introduce this note of uncertainty in section 3 or expand it in section 2.1.
Figure 2: I’m expecting that this figure will be published as single column figure. If so, legends and labels will become too small with the current layout. Please increase all font sizes in that case.