------------ The README describes ERA5 atmospheric reanalysis data used to study anthropogenic glaciation of supercooled liquid-water clouds and cloud perturbations induced by anthropogenic cloud condensation nuclei. We sampled the meteorological conditions for a copper smelter in Rouyn-Noranda (Latitude 48.2530°, Longitude -79.0163°), Canada; an oil refinery in Regina (Latitude 50.4849°, Longitude -104.5763°), Canada; metallurgical plant in Cherepovets (Latitude 59.1442°, Longitude 37.8482°), Russia; and cement plant in Fokino (Latitude 53.4445°, Longitude 34.4092°), Russia. Additional information Hannes Keernik hannes.keernik@ut.ee Velle Toll velle.toll@ut.ee This work is funded by the Estonian Research Council grant PRG1726. ------------ DATASET ------------ The dataset contains datetimes and the values of meteorological parameters characteristic of anthropogenic cloud perturbations based on ERA5. Creators: Hannes Keernik, Jorma Rahu, Velle Toll Organisation: University of Tartu Rights-holder: University of Tartu ------------ TERMS OF USE ------------ Copyright 2024 University of Tartu. This dataset is licensed by the rights-holder under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/. ------------ CONTENTS ------------ ERA5_location.csv meteorological conditions for glaciation events for each location ERA5_location_tracks.csv meteorological conditions for ship-track-like CCN perturbations on clouds for each location ERA5_units_longnames.csv names of the parameters from ERA5 together with units; Lower tropospheric stability is calculated as the difference in the potential temperatures between 700 hPa and 1000 hPa pressure levels. ------------ METHOD and PROCESSING ------------ We compare the meteorological conditions favourable for glaciation events at Rouyn-Noranda, Regina, Cherepovets, and Fokino in the years 2000 to 2021 to the meteorological conditions favourable to CCN-induced cloud perturbations at the same sites. The data for the Volsk cement plant in Russia are not used, as there we identified only glaciation events. We used data from 16 UTC for Rouyn-Noranda, from 18 UTC for Regina, and from 9 UTC for Fokino and Cherepovets from ERA5 to align the meteorological conditions to approximate Terra overpass time. We averaged the conditions over a circle with a radius of 10 kilometres. The centre of the circle was at the studied point sources of air pollution. ERA5 data are freely available from https://cds.climate.copernicus.eu/ ERA5 description https://www.ecmwf.int/en/forecasts/dataset/ecmwf-reanalysis-v5 Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz‐Sabater, J., ... & Thépaut, J. N. (2020). The ERA5 global reanalysis. Quarterly Journal of the Royal Meteorological Society, 146(730), 1999-2049. ------------