Seasonal changes are mostly driven by the hydrological cycle. However, we noticed a clear difference between the volcano and the nearby valley, which we believe is caused by surface freezing at higher elevations during winter that inhibits recharge. (4/5)

Between 2013 and 2018, we observed elevated seismicity below the volcano, lower velocities at greater depths, and then a period of quiescence with increasing velocities. From these observations, we infer a change in recharge behaviour. (3/5)

We found that seismic velocity around the volcano increased significantly at the start of the 2004-2008 eruption period, along with surface deflation measured by GNSS. (2/5)

Excited to announce that our article on seismic velocity changes at Mount St. Helens is now freely accessible, following the embargo period. (1/5 - see further details in comments)

You can read the full open-access article on GFZ's repository: lnkd.in/gjZ5TzFR