Internet macroseismology in Finland: current observatory practice

This article describes how macroseismic observations about local and regional earthquakes and other physical phenomena are currently collected in Finland. The questionnaire dates back to 1998 and aims at assessing the seismic intensity according to the European Macroseismic Scale. It was placed on the Internet at the turn of the 2000s. Data collection over the Internet is fast and convenient, but strongly biased in favour of positive responses. Hundreds of responses can be obtained even after small earthquakes. Examples of reported phenomena are given. It requires effort to identify the source of ground shaking.