The data were measured by a remote sensing instrument, in particular a CL51 ceilometer installed at ONERA (Toulouse). Between September 19 and December 13, 2021, a volcanic eruption occurred on the island of La Palma, Spain. After tracking the transport of SO2 particles with the TROPOMI satellite, between September 24 and 25, 2021, these particles crossed the sky over Toulouse and were detected by the lidar mentioned.

The data comprise pre-processed distance-corrected signal profiles for the entire duration of the event. They have a spatial resolution of 10 m and a temporal resolution of 2 min/profile, and cover a height range from 200 m to 15,000 m.