Predictions regarding possible earthquake magnitudes or even the extent to which a tsunami is likely to strike, still bear no certainty.
This point was made by Deputy Director of the Coastal Zone Management Unit, Dr. Lorna Inniss, who stressed that there was a concept called uncertainty associated with predictions. "We need to understand the issues of uncertainty," she said.
She made these comments recently during a lecture in the Henry Fraser Lecture Theatre at the University of the West Indies, on the topic: The Great East Japan Earthquake and Tsunami: One Year Later.
Dr. Inniss, who is also co-chair of the Department of Emergency Management’s Standing Committee on Coastal Hazards, told the audience the Japan Met Agency initially reported the March 11, 2011 earthquake at 7.9 magnitude, and a tsunami warning was issued some two to three minutes later.
However, as analysis continued, the earthquake was upgraded to a 9.0 magnitude, and allowed for a fast upgrade of the tsunami warning.
"One of the lessons we will learn is the uncertainty associated with these predictions. The [Barbados] Meteorological Office gets hammered if they say the rain is going to fall and you go outside and see the sun shining," she stressed.
She added that in Japan, in one of the towns with all the equipment in place, the warning system instruments failed when the earthquake occurred, and the residents got no warning. However, after feeling the tremors residents started to leave, but some still died.
Dr. Inniss pointed out that the role of science in dealing with such natural disasters was important. However, she cautioned that even with research, Barbados will always have some uncertainty associated with tsunamis because the number of real events was so low. "We just don’t get enough of them to understand how they work very well," she said.
To curb this problem, the co-chair explained that the work of science plays a critical role in the process. "We need to close the gap on the projected height and the actual height of waves. We need to reduce the uncertainty with the estimates of magnitude.
"So the role of science is critical but we can’t forget the uncertainties. Science helps us to understand the hazards, helps us to understand the sources in the area, how far away, and what is the risk," Dr. Inniss indicated.
But, while highlighting the importance of science and creating adequate warning systems, the deputy director made it clear that there were no warning systems for earthquakes.