Dear Joseph,

thanks so much for the improved version of the manuscript. I studied it and your replies to the referee comments, and would like to recommend a couple of minor revisions for the final version:

The first part of section 5.2 and Fig 11 heavily rely on data collected the framework of various aircraft campaigns. I would suggest to include campaign-specific citations here, e.g. for IMECC

Messerschmidt, et al.: Calibration of TCCON column-averaged CO2: the first aircraft campaign over European TCCON sites, Atmospheric Chemistry and Physics, 11(21), 10765-10777, doi:10.5194/acp-11-10765-2011.

Figure 7 included upon request of referee 2 is by far not as informative as it could be. Would you please replace it by separate panels showing XAIR as fct of SZA for the complete datasets, using old and the new linelists? This would demonstrate in a very convining manner that XAIR is improved (flatter) with the new linelist. Ideally, show separate panels (adding some vertical offset between old and new results for clarity if needed) for each site to reveal any systematic differences between sites (which ideally should not exist).

Do you think that the retrieved values for the speed dependent shift parameters are significant? The reported error bars are large for at least a subset of lines. Do you recommend for atmospheric work to use the value as reported, or to apply a smooth interpolation in m or to omit the parameters for all lines? Perhaps you could add a short comment on this point in the paper (or I overlooked...)?

The conclusion "measurements made at SZA > 82 deg no longer have to been discarded" is a bit vague. Do you feel that the SZA range for TCCON should be extended to a new, higher limit (e.g. 86 deg), as supported by datasets from several sites (Fig. 10), or even accept the whole range of SZAs (then only Lamont data - becoming increasingly noisy - remain as supporting evidence)?

There are a few typos in the new manuscript:

line 12: spectrometers that are part of
line 32: below
line 140: are two blanks before "Abrarov"?
line 214:red line in my printout after "2014a)"
line 338: missing blank before "(Hartmann"

Yours
Frank