Data associated with paper - 'A major combustion aerosol event had a negligible impact on the atmospheric ice-nucleating particle population' All files in .xlsx format for use with Microsoft Excel, except SEM_data, which is in .csv (also accessible by Excel) Key for Cold_stage_data_xxxxxx excel workbook sheet name: UL - micro litre-NIPI IR - InfraRed NIPI MF - Microfluidics cold stage (pico litre NIPI) Any queries to Michael Adams, eempa@leeds.ac.uk