MVO issued a statement about Soufrière Hills on 28 January explaining overall trends observed in monitoring data since lava extrusion ended in 2010.
They noted that although activity at the volcano had been low when analyzed on a week-to-week basis, subtle trends have emerged in the data in recent months that indicate an overall but small increase in unrest.
The number of volcano-tectonic earthquakes were low, averaging one per day since the last eruption ended, though during 2018-2021 the average increased from 0.4 to 1.2 per day.
Fumarolic temperatures which initially showed a cooling trend during 2013-2017 began to rise in 2018.
The increase was most notable at one specific fumarole that had a temperature increase from 200 to 500 degrees Celsius; the high temperature was similar to those last recorded in 2013.
Sulfur dioxide gas flux during 2020-2021 averaged 100-200 tonnes per day higher than the fluxes recorded 2018-2019, though remained below 2012-2013 levels.
Slow inflation of the whole island had continued since 2010, with no changes to the patterns of deformation; changes associated with volcano-tectonic swarms were only observed in areas close to the dome.
An increase in rockfall activity was also noted.
MVO reiterated that these changes since about 2018 were minor and did not merit an increase in the Hazard Level, which remained at 1 (on a scale of 1-5).
Source: Montserrat Volcano Observatory (MVO)