Secondary Ice Production Study among the three runners-up for the 2024 ACP Paul Crutzen Award

acp_Paul_crutzen_award_secondary_ice — High-Speed video frame sequences of cloud droplets colliding with ice particle at −5 °C (a), −7 °C (b) , and −10 °C (c). From Seidel et al., ACP (2024).

The article Secondary ice production – no evidence of efficient rime-splintering mechanism coauthored by the scientists from Cloud Microphysics Group at IMKAAF and Institute for Tropospheric Research (TROPOS, Leipzig), was selected as one of the three runners-up for the 2024 ACP Paul Crutzen Publication Award. The annual award was created in honor of Paul Crutzen, Nobel Prize winner and former director of the Max Planck Institute for Chemistry in Mainz to recognize outstanding publications in ACP that advances our understanding of atmospheric chemistry and physics

In this study, led by Johanna Seidel (who is now a PhD candidate in the Group of Cloud Microphysics at IMKAAF) and Dr. Susan Hartmann (TROPOS), we investigated the collisions of supercooled cloud droplets with ice targets using high speed video microscopy (see figure) and found negligible formation of secondary ice particles under a range of atmospherically relevant conditions. This study sets an experimental limit on the efficiency of the rime splintering (Hallet-Mossop) ice multiplication process and unequivocally calls for deeper study of secondary ice formation mechanisms.

Our paper was selected by an independent committee among five best publications in the Journal “Atmospheric Chemistry and Physics” (ACP), with more than 1300 articles submitted in 2024. ACP is published by Copernicus and is one of the most influential and recognized journals for the atmospheric sciences.