It was an auspicious Saturday afternoon 266 years ago on November 1, 1755. People across the colonised Caribbean didn’t know it yet, but their world was about to be rocked all the way from Europe.

Some seven hours earlier, the Great Lisbon earthquake and following aftershocks struck off the coast of Portugal causing widespread death and destruction in the European country. The disaster was made even worse as churches across Portgual were packed for All Saint’s Day, an annual Christian holiday.

Hundreds of miles across the Atlantic Ocean, however, the subterranean quake triggered long-distance tsunamis (tele-tsunamis) as the towering waves raced towards the Caribbean.

The first waves were observed along the easternmost fringes of the region later permeating throughout the Caribbean over the next several hours. Nowhere in the region were coasts spared the onslaught of massive waves.

According to the University of the West Indies’ (UWI) Seismic Research Centre (SRC), which commemorated the disastrous event on Monday (November 1), the tele-tsunamis slamming into the Caribbean islands averaged two to three metres but got as high as seven metres above sea level.

“In [1755], the Great Lisbon earthquake generated a tele-tsunami that reached the Caribbean [seven] hours after it occured. For several hours, the waves impacted the region. Waves with a run-up of 7m were recorded in some islands. In others, waves 2-3m in height were observed,” the SRC said.

Across the entire Atlantic basin and the Mediterranean Sea, the Great Lisbon quake triggered tele-tsunamis as far north as modern-day Greenland that arrived six hours after the tremor initially struck. The long-distance waves also reached as far south as southern modern-day Argentina; a whopping 15 hours later.

The SRC did not declare whether there were Caribbean casualties associated with the regional tsunami event, however, a citation from the Encyclopedia Britannica said 60,000 people died in Lisbon alone.

The SRC, which currently monitors seismic activity in the Eastern Caribbean, said that unfortunately for our ancestors there was no tsunami warning issued for the possibility of tele-tsunamis as the phenomenon was not fully understood at the time.

Even then, it may not be enough, the agency argued, as in some cases people only get mere minutes to react to such alerts.

“There was no warning in those times but an official tsunami warning can only be impactful when tele-tsunamis occur. It gives authorities sufficient time to warn persons in low-lying coastal areas. Should a tsunami occur in the region, we may have minutes to react. It is important that persons know the natural warning signs of a tsunami,” the SRC indicated.