Scientists Change Status / Alert Level for Caribbean Volcano

An explosive eruption has begun at the La Soufrière volcano in St. Vincent. Image: University of the West Indies Seismic Research Centre — An explosive eruption caused significant damage at the La Soufrière volcano in St. Vincent in 2021. Image: University of the West Indies Seismic Research Centre

Scientists responsible for the monitoring of the La Soufrière Volcano on St. Vincent in the Caribbean have changed the status / alert level there back down to “Green” after a period of quiet from a busy eruption cycle that occured in 2021. According to the University of the West Indies Seismic Research Centre (UWI SRC), seismic activity at La Soufrière, St Vincent has continued to decrease reaching the minimum activity since the tremor associated with the explosion and ash venting on April 22, 2021.

With seismic activity down, UWI SRC scientists also pointed out to other factors that led to the status change. There’s been no recent lahar signals recorded, there is no change in gas composition observations since measurements taken in late January indicated that the plume chemistry has returned to its pre- eruption chemistry, and there has been no significant change in deformation since May 2021.

Activity at La Soufrière volcano is now considered to be at levels similar to background activity recorded prior to the 2020 – 2021 eruption cycle. While the status is back to “Green”, there are still risks there. According to UWI SRC, “potential hazards associated with the presence of degassing at vents in the crater may still exists”; they also warn that “lahars on the lower flanks of the volcano may still pose a risk during periods of heavy rainfall.”

An explosive eruption has occurred at the La Soufriere Volcano on St. Vincent in the Caribbean, according to the National Emergency Management Organization (NEMO), Ministry of National Security, for St. Vincent and the Grenadines in the West Indies. Yesterday, with signs of an explosive eruption imminent, Vincentian Prime Minister Dr. Ralph Gonsalves issued an evacuation order and raised the alert level to “RED” there. The National Emergency Operations Center (NEOC) has now been fully activated on the island to deal with this impending disaster. The explosive eruption began at 8:41 am local time and continues at this moment.

La Soufriere is located in the Caribbean. Image: Google

The 2020-2021 event was the 6th explosive event to be recorded in history, with the others happening in 1718, 1812, 1814, 1902/1903, and 1949. Several effusive eruptions have also occurred at La Soufriere. In 1979, an effusive phase followed the initial explosive phase of the eruption. In 1971/1972, an effusive eruption created a lava dome that existed until the 1979 eruption.

La Soufriere’s most devastating eruption occurred in 1902; that explosive eruption claimed approximately 1,600 lives. During the last eruption in 1979, the local population was successfully evacuated and no one died.

Roughly 16,000 people that live around the volcano were displaced by the recent eruption. The overall population of St. Vincent and the Grenadines is around 100,000. With the status back to Green, some normalcy can return to those peoples lives.

The GOES-East weather satellite captured the explosive eruption and resulting ash cloud today. Image: NOAA

The volcano has ejected a cloud of volcanic ash to the north and east of the island. Forecast models used by the

Forecast models show the plume of volcanic ash will spread east over the Atlantic Ocean with time. Image: University of the West Indies Seismic Research Centre

The eastern Caribbean is no stranger to volcanic activity. 17 of the region’s 19 active volcanoes are located on 11 islands, with another 2 currently under water near the island of Grenada. The eastern Caribbean’s most active volcano prior to today’s explosive eruption was Soufriere Hills in Montserrat. Soufriere Hills destroyed the capital of Plymouth and killed 19 people when it erupted in 1997. That volcano has been continuously erupting since 1995.