|I realise figures 6 & 7 were in the first submission, but I think they need the LGM.a – PI.a anomalies. This would make it consistent with figures 2-5 and 9-12 and the rest of the paper. It would also help to redress the emphasis from analysing the glaciogenic effect alone, to a more general paper about LGM dust, which is what the introduction leads the reader to expect, and which was commented on by the other reviewer in the first round. This would also make sense given the artificial nature of the glaciogenic dust inputs used.|
I now realise I don’t understand the difference between Figure 10 (Change of net radiative perturbation by dust at the surface) and figure 7 (Change in (a) net, (b) longwave, and (c) shortwave downward radiation at the surface).
Page 13, lines 13-19: Is there a longwave aerosol-cloud effect in the northern hemisphere also? E.g. looking at figure 7b or 10e? Otherwise, I don’t understand why this only occurs in the southern hemisphere. From figure 7c and 7a, is it possible that in the northern hemisphere it is offset by a short-wave effect, hence it doesn’t show up in figure C?
Abstract, line 15: remove ‘found’.
Page 2, line 7: “Global warming is considered an important driver in investigations seeking to clarify the mechanisms of climate change, as stated repeatedly by the Intergovernmental Panel on Climate Change (IPCC) in their assessment reports (IPCC, 2013).”
This doesn’t really make sense. Perhaps change to:
“Global climate modelling is an essential tool in investigations seeking to clarify the mechanisms of climate change, as stated in Intergovernmental Panel on Climate Change (IPCC) assessment reports (IPCC, 2013).”
Page 4, line 15: Make this sentence more direct. Change: “Previous studies that have investigated the effect of glaciogenic dust have not taken into account the feedback of the dust to the atmosphere via the oceanic thermohaline circulation. “ to highlight something like: previous studies have included a dynamic ocean in this context, so the impacts on ocean circulation globally are unknown.
Page 4, line 16: Move this sentence: “Moreover, Lambert et al. (2013) identified the possibility of polar amplification attributable to dust.” to earlier where you discuss polar amplification, and explain what Lambert did in 1 sentence or so.
Page 6, line 9: Change “and it was emitted constantly independent of the other conditions “, to “The fluxes estimated by Mahowald were added as time-invariant sources into the simulations, and are not dependent on modelled land surface or atmospheric conditions”.
Page 12, line 19: “The panels clarify that the effect of snow ageing on the radiative perturbation is minor.”
This sentence seems to contradict the results shown in figure 6 and the discussion starting on page 10 line 18?
Page 14, line 15-16: You might mention that some of this model-data disagreement is related to reconstructed warming in Alaska, which is not resolved in either LGM or LGMglac.
Page 17, line 3: I don’t think Claquin et al 2003, looked at snow albedo effect of dust?
Page 17, line 5-7. To support this statement, you need to include the LGMglac.a – PI.a anomaly in figure 6.