Each observatory provides continuous and periodic monitoring of the seismicity, other geophysical changes, ground movements, volcanic gas chemistry, and hydrologic conditions and activity between and during eruptions.
In times of volcanic unrest, observatories issue warnings and recommendations - they take on an advisory role for decision-making governmental civil defense agencies (the Federal Emergency Management Agency in the U.S. or the Protezione Civile in Italy) and ideally continue producing observational data.
Earthquakes Underlying all observatory operations is an ongoing program of fundamental research in volcanic processes, supplemented by collaborative studies with universities, government agencies (in the U.S. for instance with other US Geological Survey centers, and NOAA), industry and non-governmental organizations.
Such research typically includes direct interpretation of the monitoring and eruption data, and it leads to formulation of conceptual models that can be tested by theoretical or laboratory simulations of volcanic systems.
The oldest volcano observatory is the Osservatorio Vesuviano (founded 1841) in Naples, now a member of the Italian government agency INGV.