Tue | Oct 23, 2018

Peter Espeut | Why no tsunami alert?

Published:Friday | January 12, 2018 | 12:00 AM

At 9:51:31 p.m. last Tuesday, 21 miles underground, an earthquake of magnitude 7.6 on the Richter Scale shook the Earth between the Cayman Islands and Honduras.

That was a big one! It is one of the largest quakes to take place in the Caribbean in recorded history! Bearing in mind that the massive earthquake that levelled Port-au-Prince, Haiti, on January 12, 2010 (today is its eighth anniversary) was of magnitude 7.0, had last Tuesday's earthquake taken place on mainland Jamaica, we might not be here today.

When any undersea earthquake, landslide or volcanic eruption takes place, a tsunami is to be expected. For the uninitiated, a tsunami is a wave or series of waves that move like a wall of water. They can strike land with powerful destructive force, potentially travelling miles inland, obliterating infrastructure.

Jamaica has a history of destructive tsunamis, although I am not sure if we teach it in those terms. Most of us know about the 1692 earthquake that sank Port Royal, but we may not realise that the tsunami from that earthquake affected not only Port Royal, but flooded several other eastern Jamaican coastal towns, including Port Maria, Annotto Bay, Buff Bay, and Port Antonio. That same tsunami wave reflected eight times between the south coast of Cuba and the north coast of Jamaica, like between the walls of a bathtub.

On October 3, 1780, a great submarine landslide off Savanna-la-Mar caused a tsunami that swept through that town and more than a mile beyond. Two large ships and a schooner were at anchor in the harbour, but were driven a considerable distance inland, and were wrecked among some mango trees. When the water receded, not a building was standing in the town or its surroundings.

The 1907 earthquake is famous for destroying Kingston, but the tsunami it generated also flooded Port Royal, Port Maria, Annotto Bay, Buff Bay, and Port Antonio.

And so news of a massive nearby undersea earthquake should have been a cause of major concern to Jamaican authorities, because it could generate a major tsunami of catastrophic proportions.

At 9:57 pm last Tuesday - six minutes after the earthquake began - the Pacific Tsunami Warning Centre based in Hawaii, operated by US National Weather Service, issued its first tsunami advisory: "Hazardous tsunami waves from this earthquake are possible within 1,000km of the epicentre along the coasts of Cayman Islands, Jamaica ... . Government agencies responsible for threatened coastal areas should take action to inform and instruct any coastal populations at risk in accordance with their own evaluation procedures and the level of threat."

The height of the forecast tsunami was about 1m (three feet) - high enough to flood both international airports, as well as Negril, Lucea, Green Island, Yallahs, Bull Bay, and Harbour View. According to the advisory, the estimated time of arrival (ETA) of the wall of water in Montego Bay was 10:40 p.m. (43 minutes after the advisory was sent), and in Kingston was 11:14 p.m. (77 minutes after the advisory was sent).

This is not a lot of time to notify coastal residents to evacuate, and then for them to actually evacuate, and for the authorities to put the national rapid-response mechanism in place.

By all accounts, before the ETA of the tsunami, no one was warned, and nothing was activated or put in place.

Was anyone on duty to receive the early warning of approaching disaster? And if anyone was on duty, and saw the early warning advisory, did they have the authority to issue a national tsunami alert, tsunami advisory, or tsunami warning? What is the standard operating procedure for issuing an official alert? If the UNESCO-IOC Tsunami Early Warning Mechanism issues an official authentic tsunami advisory for Jamaica, what else must happen before the Jamaican authorities issue a national advisory?

For a long time, Jamaica has been on notice to expect a tsunami.

The Caribbean undersea volcano called Kick 'Em Jenny has shown signs that it is about to erupt. When that happens, it is predicted that the tsunami it will generate will threaten Jamaica within dozens of minutes.

Eruption of the undersea volcano called Cumbre Vieja, off the Canary Islands, is expected to generate a mega-tsunami that could impact Jamaica.

When the next tsunami heads our way, will anyone be awake to get the early-warning message? Will any public warning be issued? Or will we drown in our beds?

- Peter Espeut is a sociologist and natural resource manager. Email feedback to columns@gleanerjm.com.