Everyone is familiar with Pompeii, the Roman city that was entombed after nearby Mt Vesuvius erupted in AD 79. What is less well-known is that a similar experience happened to a modern-day city just over 20 years ago.
Montserrat is one of the Lesser Antilles Islands, an archipelago in the Caribbean Sea, north of South America. Many of the islands are volcanic, and their location roughly traces the edge of the Caribbean Plate along its boundary with the tectonic plates (North and South American Plates) beneath the Atlantic Ocean. The Caribbean Plate is overriding the North American Plate. As the plates collide, the mantle of the overriding Caribbean Plate melts, generating magma that rises to the surface and feeds many volcanoes in the region.
Aside from a seventeenth-century eruption, Soufrière Hills, a volcano on the southern part of the island, had been mostly quiet during historical times.
All this changed in mid-1995. On the 18th of July 1995, an eruption of ash prompted an evacuation of almost 5,000 residents. The volcano grew a new dome on November 1995. By January 1996, the old dome was rapidly buried and between March and September of the same year, the first pyroclastic flows poured down the Tar river valley. This created a new delta and in April the south of the island was evacuated. The capital city of Plymouth was also abandoned, with government officials and many residents relocating to Brades, on the northwestern tip of the island in 1998, to this day, Brades is the “de facto” capital of the island, although a new capital is being built in the Little Bay area. Legislatively, Brades was never officially made the capital, so Plymouth is still the “de jure” capital, and the only capital city in the world that is officially abandoned.
By 26 December 1997, when the most extreme explosive event occurred, approximately 90% of the resident population of over 10,000 had had to relocate at least once and over two-thirds had left the island. Virtually all the island’s important infrastructure was destroyed or put out of use. The private sector collapsed and the economy became largely dependent, directly or indirectly, on British aid funding public sector and related activities.
An area around the volcano, containing about two-thirds of the island, is vulnerable to volcanic hazard and is a no-go area. Around 40% of the island is unaffected by volcanic activity but these areas may be prone to ash falls and volcanic gases during any volcanic activity and if the wind is blowing from south to north. These sometimes cause cancellation of flights to and from the island.
In addition there are three areas around the coastline which are designated Maritime Exclusion Zones where no shipping should enter. The largest of these extends for 4km on the eastern side of the island and there are two on the western side of the island. The most southerly of the two extends for 2km off shore and the third for a half kilometre off shore.
An island-wide siren system is installed to warn of volcanic activity. The sirens are tested daily at 12:00 midday. Radio Montserrat (ZJB) also provides regular scientific updates and advice to listeners.
The following sites were used for the creation of this blog post: