An updated microphysical model for particle activation in contrails: the role of volatile plume particles

Kurzfassung

The aviation industry contributes approximately 3.5 % towards global anthropogenic effective radiative forcing (ERF) (Lee et al., 2021). This share is projected to increase, as the sector is comparatively challenging to decarbonise (Grewe et al., 2021), notwithstanding anticipated compound annual growth in global passenger traffic of 3.6 % from 2027–2043 (Airbus, 2024). Estimates for 2018 indicate that the largest contribution towards net aviation ERF (+100.9 m Wm−2) is from contrail cirrus (+57.4 m Wm−2), with remaining contributions from accumulated CO2 emissions (+34.3 m Wm−2), followed by NOx (+17.5 m Wm−2) (Lee et al., 2021). The sign and magnitude of the contrail cirrus ERF depend inter alia on optical thickness and spatiotemporal coverage (Kärcher, 2018; Schumann et al., 2012), which are determined by ice crystal microphysics and hence the contrail formation pathway.