Ice Nucleating Particle concentrations from Rothera research station in Antarctica measured using the offline, wash-off filter method from filters which were exposed in February 2023

Ice Nucleating Particle concentrations were measured by exposing polycarbonate filters for 48 hours at East Beach, Rothera on the Antarctic peninsula as part of the Southern Ocean Clouds (SOC) project. The filters were stored and shipped back to the British Antarctic Survey at -20 C, where they were analysed using the offline, wash-off filter method following the Vali (1971) methodology and using a droplet freezing array set-up similar to the one described by Budke and Koop (2015). The dataset presented here is from filters which were collected between the 4th of February 2023 13:50 UTC and the 22nd of February 2023 13:50 UTC: which covers the first SOC special observing period during which aircraft measurements of clouds and aerosol were conducted around Rothera station. The Ice Nucleating Particle concentrations are used to derive a parameterisation for INP concentrations as a function of temperature which is subsequently used to investigate how processes in mixed-phase clouds (INP and droplet number concentration and the spatial distribution of liquid and ice) are represented in the Met Office Unified Model (MetUM); and the sensitivity of the MetUM to changes in these processes and resulting cloud radiative effect. The Southern Ocean Clouds was supported by NERC as part of the CloudSense Programme and it was funded by the project grant number NE/T006404/1.