Aviation and the Environment: Rating Airlines on Their CO2 Efficiency

Abstract

The aviation industry contributes about 2% to the total global manmade CO 2 emissions, which is seen as the main (manmade) greenhouse gas inducing climate change. This paper focuses on the design of a CO 2 rating system which makes it possible to make a fair comparison of the environmental performance of airlines with respect to CO 2 on the basis of public available data. It is argued that airlines can be best compared on the amount of CO 2 emitted per revenue ton kilometer (CO 2 / RTK) on the basis of distance sectors. Therefore, an airline is rated on various distance sectors. The CO 2 efficiency scores of an airline within a distance sector can then be compared with other airlines. For nine airlines the CO 2 efficiency is modeled, and the distance sector boundaries are determined. It is shown that the relative positions of airlines may change when choosing a different boundary, since the CO 2 efficiency changes with distance. It is also shown that on the basis of public available information it is difficult to accurately determine the CO 2 / RTK of an airline, which is due to lack of detail in public available data. A sensitivity analysis has been performed to show on which parameters information in greater detail is needed.

Rank-order concordance among conflicting emissions estimates for informing flight choice

“…Civil aviation GHG emissions are estimated as global-level inventories (Olivier, 1995;IPCC, 1999;Wilkerson et al, 2010;Simone et al, 2013;Wasiuk et al, 2015), regional-level inventories (Wasiuk et al, 2015), national-level inventories (Pejovic et al, 2008;GAO, 2009), airport-level inventories (Hudda et al, 2014;Sherry, 2015), airline-level inventories (Miyoshi and Mason, 2009;van Dorland et al, 2009;Zou et al, 2012), and as performance statistics for individual engines or aircraft (Green, 2002;DuBois and Paynter, 2006). At each of these levels there is a well-defined clientele for these emissions-estimate data, and hence there is a substantial volume of research being continually conducted and published on all of these levels.…”