Dear Editor,
Kick ’Em Jenny is an active undersea volcano located about 8 kilometers (5 miles) north of the island of Grenada in the Caribbean Sea. It is the only “live” submarine volcano in the Eastern Caribbean and one of the most active from time to time.
At the end of August 2025, the region was jolted when approximately 800 tremors were detected between August 27 and 28. The University of the West Indies (UWI) Seismic Research Centre (SRC) out of Trinidad and Tobago constantly monitors the volcano and maintains a maritime exclusion zone.
The UWI SRC refers to the tremors as the “unrest.” The last period of “unrest” was a four-day period in February 2024, during which over 3,400 events were recorded.
The volcano's first recorded eruption was in 1939, when a powerful explosive event was witnessed from northern Grenada. This eruption caused minor damage to nearby islands. Grenada reported high waves as well the islands of the Grenadines such as Carriacou and Petite Martinique. A small tsunami reached the west coast shores of the island of Barbados which reportedly caused minor coastal flooding.
Since its discovery, Kick ’Em Jenny has erupted at least a dozen times. Most of these eruptions have been detected by seismic and acoustic instruments, as they did not break the surface of the sea. The activity has ranged from explosive events that produced ash clouds and small tsunamis to more quiet, effusive eruptions.
The last confirmed eruptive episode of Kick ’Em Jenny took place on April 29, 2017. This eruption, like many others since 1939, was a short-lived event primarily detected by seismic signals.
There is a Kick ’Em Jenny Submarine Volcano Alert Level scale in place. Green indicates the volcano is quiet; Yellow indicates the volcano is restless, and this is the current level of alert. The other alert levels are, Orange, highly elevated level of seismic activity which could be an indication that an eruption may occur with less than 24 hours’ notice; and alert level Red, eruption is in progress or may occur without further warning.
According to research carried out, the primary tsunami threat from a major eruption of Kick ’Em Jenny is to the islands in the eastern Caribbean such as Grenada, because of its close proximity; The Grenadines (particularly the southern islands like Carriacou and Petite Martinique); St. Vincent; Barbados; Martinique; Trinidad and Tobago; and St. Lucia.
A very large tsunami could potentially reach a wider area, including the northern coast of Venezuela and the Leeward Islands, which would include St. Maarten. However, the severity of the threat decreases with distance from the volcano.
The travel time for a tsunami to reach St. Maarten from Kick ’Em Jenny would depend on the size and force of the eruption. However, modeling and historical data from past events indicate that within 90 minutes, it would take a tsunami to reach the Leeward Islands and Puerto Rico
The potential impact based on research to St. Maarten would be coastal flooding that would lead to potential damage to infrastructure located along the coast, including resorts and homes.
Damage to infrastructure from powerful waves can disrupt transportation, power, seaport, airport, and communication systems. Besides those being damaged, this would further reflect on economic disruptions similar to what Hurricane Irma did in 2017.
Then there is the threat to life, particularly for people on beaches (if there is a tsunami during the daytime) or in low-lying coastal areas.
Predicting the exact height of a tsunami wave that would reach St. Maarten from an eruption of Kick ’Em Jenny has been described as a complex task, as the wave height would depend on several factors, including the magnitude and type of the eruption.
According to research, the most significant tsunamis from Kick ’Em Jenny would likely be caused by a large submarine landslide or a powerful explosive eruption that displaces a large volume of water. The current depth of the volcano’s vent (around 268 meters/885 feet) makes a large, tsunami explosive eruption unlikely.
The underwater environment – topography – determines the height of a tsunami wave. In deep water, a tsunami is a very long, low wave, but as it approaches a coast and enters shallower water, the wave slows down and its height increases dramatically, a process called shoaling.
An island’s coastal structure, harbors, and bays can amplify or diminish the size of a tsunami wave. The 1939 eruption of Kick ’Em Jenny generated a tsunami with a wave height of 1-2 meters (three to six feet) in the southern Grenadines and northern Grenada. The effect on distant islands was much smaller at the time.
A study on the tsunami threat to Puerto Rico from Kick ’Em Jenny, which is a similar distance away as St. Maarten, modeled a worst-case scenario. The results showed a maximum wave amplitude of 0.156 meters at a virtual buoy off the coast of Ponce, Puerto Rico. While this is a small wave, it’s important to remember that this is the amplitude in the open ocean.
Therefore, for St. Maarten, a small to medium-sized tsunami from Kick ’Em Jenny would likely be a relatively small wave in open water, but it could still be dangerous. The wave could increase in height as it reaches the shallow coastal areas and could cause damaging coastal flooding, especially in low-lying areas.
Caribbean nations can take a multi-faceted approach to mitigate the damage of a major tsunami, even if the probability is low. This involves a combination of pre-emptive planning, infrastructure measures, and public education. The key is to build a comprehensive disaster management strategy that integrates all levels of society.
Roddy Heyliger
