The Government of St. Vincent and the Grenadines, on the advice of scientists from the Seismic Research Centre, University of the West Indies, lowered the volcanic alert level at La Soufrière from yellow to green, effective Wednesday.
A green alert means that seismic and fumarolic (steam vent) activity is at or below the historical level and no other unusual activity has been observed.
Activity at the La Soufrière volcano is now considered to be at levels similar to background activity recorded prior to the 2020-2021 eruption.
The overall trend of decreasing seismicity continued during the last month, the National Emergency Management Organization (NEMO) said on Wednesday.
No change in gas composition has been observed since measurements were taken in late January.
“This indicates that the plume chemistry has returned to its pre-eruption chemistry. There has been no significant change in deformation signal since May 2021,” NEMO said.
The alert level was lowered from orange to yellow on September 15, and since then, activities have either been lowered considerably or ceased.
NEMO, however, said the La Soufrière trail remains closed due to the uneven and dangerous terrain.
It reminded the public of the potential threat for lahars (floodwaters mixed with ash, other volcanic materials, mud, debris, and rocks) after rainfall and the threat to persons living and moving across river valleys closer to the volcano.
“Residents and motorists in areas close to the volcano and persons traversing rivers and streams during periods of heavy rainfall should always remain vigilant,” NEMO said.
La Soufrière, a stratovolcano, began an effusive eruption on December 27, 2020. On April 9, 2021, there was an explosive eruption, and the volcano “continued to erupt explosively” over the following days, with pyroclastic flows. The activity pattern of the eruption was comparable to that of the event that occurred in 1902, which had a Volcanic Explosivity Index of four. The volcano is known to have erupted 23 times in the last 4,000 years and had been dormant since 1979.
CMC/
