Long-term ice nucleating particle concentrations by offline vacuum diffusion chamber measurements from the Amazon, the Caribbean, Central Europe, and the Norwegian Arctic

The data set reports on long-term measurements of ice nucleating particles (INPs) from four observational sites: 1. Amazon Tall Tower Observatory (ATTO, 2.144° S, 59.000° W, 130 m AMSL, Brazil), 2. Volcanological and Seismological Observatory of Martinique (OVSM, 14.735° N, 61.147° W, 487 m AMSL, Martinique, Caribbean), 3. Taunus Observatory (TO, 50.221° N, 8.446° E, 825 m AMSL, Germany) and 4. Zeppelin Observatory (ZO, 78.908° N, 11.881° E, 474 m AMSL, Ny-Alesund, Svalbard, Arctic). The presented data covers data from May 2015 to January 2017. Samples were usually collected every day or every two days at local noon for 50 minutes at 2 L min-1, resulting in 100 L of air volume. After transport samples were analyzed in our laboratory in Frankfurt using the vacuum diffusion chamber FRIDGE. Each sample was analyzed at multiple combinations of temperature ( 20 °C, -25 °C, and -30 °C) and relative humidity (95%, 97%, 99%, 101% w.r.t. water). INP concentrations per liter are reported for each condition (the paper focuses on the highest humidity). This data supplement is related to a scientific publication (doi:10.5194/acp-2020-667).