Dear Dr. Ingeborg Levin, thank you very much for your suggestions. We have made the technical changes suggested. You can find the changes in the third version of the manuscript that has been submitted. Technical corrections - Figure 1 would largely benefit from some more quantitative data. The current information could easily be given in one sentence of the text without an extra figure. Quantitative data (i.e. temperature, burial pressure, C content and methane isotopic signatures) have been added. Please note that isotopic ranges for coal-derived methane emissions are based on the isotopic values on Table 2. Therefore, Figure 1 has been moved to the discussion section and it is now Figure 3 (see line 525). In Figure 3 please add y-axes titles (del13C) in all "lines" and an x-axis title (1/CH4) in the second column (4th line.) Titles have been added. 1 Carbon isotopic signature of coal-derived methane emissions 2 to atmosphere: from coalification to alteration 3 4 Giulia Zazzeri1, Dave Lowry1, Rebecca E. Fisher1, James L. France1,2, Mathias Lanoisellé1, Bryce F.J. Kelly4, 5 Jaroslaw M. Necki3, Charlotte P. Iverach4, Elisa Ginty4, Miroslaw Zimnoch3, Alina Jasek3 and Euan G. Nisbet1. 6 1Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX 7 2University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ 8 3AGH-University of Science and Technology, Al.Mickiewicza 30 Kraków, Poland 9 4Connected Waters Initiative Research Centre, UNSW Australia 10 11 Correspondence to: Dr Giulia Zazzeri (
[email protected]) 12 Prof Euan Nisbet (
[email protected]) 13 14 Abstract.