Near-Earth modulation (NEM) index in 1-hour resolution

New version of the Near-Earth modulation index (also called modulation parameter or potential) in 1-hour cadence. The naming convention has been switched to "Near-Earth modulation" index to emphasize the local nature of the quantity.

The NEM index was computed from the data of 38 neutron monitor stations in 1-hour resolution, utilizing the yield function from Mishev et al. 2020 and the local interstellar particle spectrum from Boschini et al. (2020, 2021).

Details can be found in the publication Väisänen, P., Larsen, N., Koldobskiy, S. A., Similä M., Similä, M., Pelosi, D. & Orcinha, M. (2026, soon to be submitted) High cadence hourly near-Earth modulation index and cutoff rigidities: Towards a better understanding of Solar-Terrestrial space weather and space climate

As the peer review process advances, this page will be updated. This version 3 includes a fix to cutoff rigidty values from Aug 2025 to Jan 2026. Version 2 included a compilation error.