I thank the authors for their thorough response to the reviewers’ comments. I believe you’ve done a good job of responding to their comments, and with a few very minor additional changes I’ll be happy to accept this paper. Please see my specific comments below. In addition, while making these last revisions, it would be useful to improve the grammar. While your response says that you asked the two native English speakers to read the paper, you do not actually say if they did so, and in any case a final look by the native speakers is warranted.

Thank you for all your work on this paper, which I think will be a very valuable contribution to the community, and I look forward to accepting it.

Regards,
Drew Shindell


Uncertainty analysis (P18, starting line 15): I appreciate very much that you’ve added a discussion on uncertainties following the suggestion of reviewer 2. This is very helpful. At the start of this section, the text states that you use a Monte Carlo analysis ‘following the methodology described in Bo et al (2008) and Wei et al (2008)’. I would like you to please add here a brief description of where the emission factor and activity data uncertainty estimates come from. That is, please explain (1) do the values themselves come from the two cited papers, or do you just use the methodology of those papers but the data comes from elsewhere, and (2) whether the uncertainty estimates come from those two papers or not, provide readers a general description of where those uncertainty estimates come from.

P18, L29: Please define the ‘coefficient of variation’ at the first usage (I think that’s here) as this statistic is likely not so familiar to many readers.

P2, L3: Change ‘estimated’ to ‘projected’.

P2, L9: You describe that these ‘maximum feasible reductions’ are based on energy-saving policies and end-of-pipe technologies. Hence please add something like “using energy-saving policies and end-of-pipe technologies” after ‘maximum feasible reductions’ since of course one could eliminate even more emissions if society changed more drastically, so ‘maximum feasible’ needs some context about the assumptions of what’s considered feasible.

P19, L12: Delete ‘the’ before ‘emission factor’.

P20, L29: I recommend adding the paper Shindell et al., Science, 2012 along with the citation to UNEP and WMO, 2011 as the latter can sometimes draw criticism for not being a peer-reviewed journal (which is part of the reason we published the Science paper, to deflect such criticism).

P21, L27: Add ‘an’ before ‘elasticity’.

P21, paragraph starting with L21: The response to reviewers contains a much more detailed explanation of how the elasticity coefficients are used, and I think the authors should seriously consider adding this to the text. It may be in Zhao et al, but far easier for readers to have these few additional lines of explanation here.

P22, L17: Change ‘with’ to ‘as’ and change ‘of’ to ‘in’.

P40, L66: Change ‘as of’ to ‘through’ (I believe that’s what’s meant).

P40, L22: While true that these agree fairly well (and I’d add ‘fairly’ before ‘well’), I think you should add a statement such as “although this agreement is very sensitive to the trend start and end year choices”. Clearly the apparent agreement with SCIAMACHY would be lost if you started in 2006 instead of 2005, for example, so you shouldn’t overstate this.

Thank you for your revisions. I'm pleased to accept your paper.
Regards,
Drew