Time series of long-period magnetotelluric data collected between October 2023 and March 2024 at 9 sites in Scotland, UK, as part of the NERC projects NE/S007407/1 and NE/V002694/1. The data consist of measurements of the Earth’s natural electric and magnetic field variations in five channels and with a 1-sec sampling rate. There is a text file with the site coordinates, a single PDF file containing all relevant metadata, and individual ASCII files for each site named by the site ID.

Long-period Magnetotelluric time series recorded in Nov 2021 to Jan 2022 at site SH54, South Snowdonia, Wales, UK. Funded by NERC, grant number: NE/V002694/1 "SWIMMR Activities in Ground Effects (SAGE)". These data consist of measurements of the Earth’s natural magnetic and electric field variations.