Hendrick, M. F., Cleveland, S., & Phillips, N. G. (2016). Unleakable carbon. Climate Policy. http://dx.doi.org/10.1080/14693062.2016.1202808
When the paper was first published, the authors did not convert CO2e back to CH4 using a molar mass ratio ((16 g/mol CH4)/(44 g/mol CO2)) before applying global warming potential values, and did not calculate the additional radiative forcing contributed by CH4 leakage in relation to McGlade and Ekins’ (2015) utilizable portion of remaining natural gas reserves (179.5 Gt CO2e). This has now been corrected in Table 1, please see the Supplemental Materials for the calculations used. This oversight changes the magnitude of the results reported in Table 1, but not the direction. The following changes have also been made in the text as a result of this correction:
Abstract: The sentence ‘We demonstrate that unless unleakable carbon is curtailed, up to 80–100% of our global natural gas reserves must remain underground if we hope to limit warming to 2°C from 2010 to 2050.’ has been amended to read ‘We demonstrate that unless unleakable carbon is curtailed, up to 59–81% of our global natural gas reserves must remain underground if we hope to limit warming to 2°C from 2010 to 2050.’
Last paragraph on the fourth page of the paper: The sentence ‘If we assume that 3.2 and 9.7 Gt CO2 of the utilizable portion of recoverable gas reserves are leaked under low and high leakage scenarios, respectively, we can then convert these emissions to equivalent CO2 emissions (CO2e) to reflect uncombusted CH4.’ has been amended to read ‘If we assume that 1.8% and 5.4% of recoverable natural gas reserves are leaked under low and high leakage scenarios, respectively, we can then calculate the maximum extractable fraction of natural gas reserves that could be combusted and leaked while limiting total emissions to 179.5 Gt CO2e.’
First paragraph on the fifth page: The sentences ‘Low estimates of CH4 emissions evaluated over a centennial time horizon show that unleakable carbon enhances CO2e from the combustion of utilizable portions of remaining natural gas fuels by 30% (Table 1, Supplementary Materials). This comprehensive carbon accounting demonstrates that stakeholders may need to prepare to leave 80% of remaining global natural gas reserves in the ground instead of just 50%. Alarmingly, high estimates of CH4 emissions on decadal time scales increase CO2e emissions by 230% (Table 1, Supplementary Materials). This worst-case leakage scenario indicates that stakeholders may not be able to afford to extract any remaining global natural gas reserves, and that even current, ongoing leakage across natural gas systems may present a challenge to limiting warming to 2°C from 2010 to 2015.’ have been amended to read ‘Low estimates of CH4 emissions evaluated over a centennial time horizon show that unleakable carbon enhances CO2e from the combustion of utilizable portions of remaining natural gas fuels by 9% (Table 1, Supplementary Materials). This comprehensive carbon accounting demonstrates that stakeholders may need to prepare to leave 59% of remaining global natural gas reserves in the ground instead of just 50%. High estimates of CH4 emissions on decadal time scales increase CO2e emissions by 31% (Table 1, Supplementary Materials). This worst-case leakage scenario indicates that if current levels of unleakable carbon continue unabated, stakeholders may only be able to afford to extract 19% of remaining global natural gas reserves in order to limit warming to 2°C from 2010 to 2015 (Table S1).’