Ice Nucleating Particle number concentration from low-volume sampling over the Southern Ocean during the austral summer of 2016/2017 on board the Antarctic Circumnavigation Expedition (ACE).

<strong>Dataset abstract </strong> Ice nucleating particles (INP) are a subclass of atmospheric aerosol particles, which can force heterogeneous freezing of cloud droplets at temperatures above -38 degrees C. In contrast, ice particles form from cloud droplets at temperatures below -38 degrees C due to homogeneous freezing, without INP. Due to their abundance, these particles can affect micro-physical properties of clouds, while acting as INP. During the Antarctic Circumnavigation Expedition (ACE) around the Southern Ocean, off-line filter sampling was performed. Filters were stored on the ship and analysed after the cruise at Leibniz-Institute for Tropospheric Research (TROPOS) concerning INP abundance. Here, we give INP number concentrations for sampling of 8 hour periods. <strong>Dataset contents</strong> ACESPACE_ice_nucleating_particles_frozen_fraction_from_lowvolume_filters.csv, data file, comma-separated values ACESPACE_ice_nucleating_particles_number_concentration_from_lowvolume_filters.csv, data file, comma-separated values data_file_header_frozen_fraction.txt, metadata, text format data_file_header_number_concentration.txt, metadata, text format README.txt, metadata, text format change_log.txt, metadata, text format <strong>Change log</strong> v1.1 - data files updated change dataset title to reflect low-volume sampling method addition of INP number concentration data from different temperatures addition of fraction of frozen droplets data addition of field blank filter data create separate data_file_header files add change log v1.0 - initial release of dataset