Rise in sea level ups tsunami risk

Findings show likely increase of flooding farther inland following quakes

Washington: Even minor rise in sea levels due to climate change can increase the risk of potentially devastating tsunamis around the world, a study has warned. New findings show the likely increase of flooding farther inland from tsunamis after earthquakes.

Washington, Aug. 19: Even minor rise in sea levels due to climate change can increase the risk of potentially devastating tsunamis around the world, a study has warned.

The threat of rising sea levels to coastal cities and communities throughout the world is well known, but new findings show the likely increase of flooding farther inland from tsunamis following earthquakes.

For example, the tsunami that devastated a portion of northern Japan after the 2011 Tohoku-Oki earthquake also caused a nuclear plant to melt down and spread radioactive contamination.

“Our research shows that sea-level rise can significantly increase the tsunami hazard, which means that smaller tsunamis in the future can have the same adverse impacts as big tsunamis would today,” Robert Weiss, an associate professor at Virginia Tech in the US.

For the study published in the journal Science Advances, researchers created computer-simulated tsunamis at current sea level and with sea-level increases of 1.5 feet and 3 feet in the Chinese territory of Macau.

Macau is a densely populated coastal region located in South China that is generally safe from current tsunami risks.

At current sea level, an earthquake would need to tip past a magnitude of 8.8 to cause widespread tsunami inundation in Macau. But with the simulated sea-level rises, the results surprised the team.

The sea-level rise dramatically increased the frequency of tsunamiinduced flooding by 1.2 to 2.4 times for the 1.5-foot increase and from 1.5 to 4.7 times for the three-foot increase.

“We found that the increased inundation frequency was contributed by earthquakes of smaller magnitudes, which posed no threat at current sea level, but could cause significant inundation at higher sea-level conditions,” said Lin Lin Li, a senior research fellow at the Earth Observatory of Singapore. — PTI

THE HAZARD of large tsunamis in the South China Sea region primarily comes from the Manila Trench, a megathrust system that stretches from offshore Luzon in the Philippines to southern Taiwan.