A cross-correlation-based method for determining size-resolved particle growth rates

Abstract. The particle growth rate (GR) is a key parameter in aerosol dynamics and plays a crucial role in understanding atmospheric new particle formation and its effects. A fast, robust and reproducible calculation of GRs from aerosol number-size distribution data remains a challenge. In this study, we introduce a new method that we call the maximum cross-correlation (MCC) method for calculating particle and ion GRs from number size distributions. We employed this novel method to calculate GRs from simulated data and from ion and total particle number-size distribution data from Hyytiälä, Finland. We compared our method against conventional methods for calculating the GRs and found good agreement. The MCC method enables fast and repeatable GR calculations from large aerosol datasets, which facilitates the systematic incorporation of GR analysis into new particle formation studies.