‘There will be a tsunami on Israel's shores – the question is when'

While earthquakes stronger than 7.5-magnitude have the potential to cause tsunamis, they can also be caused by underwater landslides.

By SHARON UDASIN
Dr. Beverly Goodman conducts research in the Mediterranean Sea. (photo credit: MGM LABORATORY)
Dr. Beverly Goodman conducts research in the Mediterranean Sea.
(photo credit: MGM LABORATORY)
Dr. Beverly Goodman’s refrigerator is stocked with Ziploc bags filled with standard marine sediments, deep-sea shell fragments and Byzantine poo.
To most people, these bags of muds and sands would just be bags of muds and sands. But to Goodman, a marine geoarcheologist at the University of Haifa, the sediments from between 450 and 550 BCE are indicative of a tsunami that once shook Caesarea’s waters.
Goodman and her students are working to understand undersea environmental changes and ancient coastal tsunamis in the Mediterranean Sea, in order to prepare for similar events in the future, Goodman told The Jerusalem Post during a visit to her laboratory last week. To accomplish this, they have been actively collecting sediments and exposing layers left behind by tsunamis, particularly in the Caesarea Harbor area. They have identified six tsunamis that have affected Caesarea over time, occurring with time gaps of between 200 and 2,000 years.
“There will be a tsunami on our shore – the question is when,” said Goodman, whose lab is housed in the Dr. Moses Strauss Department of Marine Geosciences, in the Leon H. Charney School of Marine Sciences.
Going farther back in time would almost definitely reveal additional events, and others may have occurred in between the six already confirmed, Goodman said.
“My guess is that we’ll probably fill in between those 2,000-year gaps,” she said.
While earthquakes stronger than 7.5-magnitude have the potential to cause tsunamis, they can also be caused by underwater landslides, Goodman explained.
The last tsunami recorded off Israel’s shores occurred in 1956, as a result of a large earthquake in Greek waters, she said. The last tsunami to cause any damage in Israel happened in the 19th century near Acre, she added. Caesarea most recently received a small tsunami in the 12th century, according to Goodman.
Researchers have developed a warning matrix for eastern Mediterranean tsunamis, but a warning of only about 20 to 30 minutes will be possible, she explained. That being said, Goodman continued, any tsunami will not have the power of those that devastated Japan and Thailand in recent years – though they will affect land about a half-kilometer inland from the coast.
“The best solution is prevention,” she said.
Ideally, Israelis would receive basic knowledge about tsunamis in school and take part in preparatory drills, she explained. In addition, the government should opt for land-based rather than marine-based infrastructure when it has the choice.
Commenting on a debate along the northern coast as to whether to construct a natural gas reception facility offshore or onshore, Goodman likewise said all such facilities must be very carefully positioned. Due to risky circumstances such as sediment slumping (moving a short distance down a slope), infrastructure should be built inland, or in a stable region if a marine environment is necessary, she stressed.
As part of her work, Goodman – whom National Geographic named an “Emerging Explorer” in 2009 – makes use of the Charney School’s diving center in Caesarea. There, she and her research team make use of both conventional diving mechanisms and rebreather technology, which allows divers to stay underwater deeper and longer by recirculating their air.
Goodman and her team members are also taking part in projects off the coasts of Cyprus and Turkey. The hope is that they will be able to develop an informational baseline regarding eastern Mediterranean tsunamis, which is generally nonexistent, she said.
“We’re really trying to bring together as much as we can, to understand this incredible resource,” Goodman said. “We’re going to be turning to the sea more and more, so it’s going to be important that we do it responsibly.”