Fig. 2: Well-to-wake carbon intensity of jet fuel.

a Comparison between results obtained from this study and jet fuel well-to-wake CI values reported in the literature. Well-to-refinery entrance includes crude oil production and transportation. Refinery entrance-to-tank includes refining and distribution. Study year refers to the time period when data were collected (not the year the study was published). Global v.w.a. represents the global volume-weighted average CI (88.7 gCO₂e MJ^-1). Whiskers are 5 and 95 percentiles of the well-to-wake CI of jet fuel produced by refineries. See references for studies conducted by MIT¹⁷ and Zhou et al¹⁸. and note that average combustion emissions are adjusted to 73.8 gCO₂e MJ^-1 for literature studies presented here. Energy-based process unit-level based allocation is adopted for refining in this study (see Methods). b 2017 country-level volume-weighted average jet fuel well-to-wake CI supply curve and emissions reduction scenarios. Each vertical stacked bar represents a life cycle stage breakdown of the volume-weighted average well-to-wake CI of one country (sorted by increasing CI value). The width of the stacked bar indicates the daily volume of jet fuel consumed in the corresponding country. The low technology improvements scenario assumes minimal routine flaring in crude oil production and transportation, and carbon capture from the fluid catalytic cracker and steam methane reformer (SMR for hydrogen production) units. The high technology improvements scenario assumes no routine flaring and minimal fugitives & venting in crude oil production and transportation, and carbon capture from all refinery process units and the use of low-carbon steam and electricity for refinery operations^{34, 41}. In addition, all carbon capture processes are assumed to be powered by low-carbon utilities. See Methods for details about these two scenarios.