p*******f 发帖数: 530 | 1 Scientists say Oakland, Alameda most vulnerable to tsunami in Bay Area
By Lisa M. Krieger
l******[email protected]
Posted: 03/15/2011 04:17:49 PM PDT
Updated: 03/15/2011 04:31:20 PM PDT
An iconic landmark helps protect most low-lying Bay Area communities from a
devastating tsunami: the Golden Gate strait.
Huge currents would race through its narrow opening, but there's a limit to
how much water can pour through the rock-lined channel into the San
Francisco Bay -- reducing the risk of inland flooding.
But while that world-famous geographic feature would spare the South Bay and
much of the Peninsula from the type of surge that leveled parts of Japan,
scientists say it would direct the brunt of the tsunami toward Alameda and
the Port of Oakland.
"The narrow mouth of the Bay really protects much of the area from the kinds
of surges we saw in Japan," said Humboldt State tsunami expert Lori Dengler
. Of greater concern, she said, "are the strong currents that cause damage
to structures," particularly in San Francisco and Oakland.
The Japanese quake directed most of its energy north of the Bay Area, so we
were largely spared. It caused $22.5 million in damages to Santa Cruz harbor
, but far greater destruction in the northern coastal towns of Crescent City
, Fort Bragg and Brookings, Ore. Flat coastal communities are the most
vulnerable to tsunamis, and if had hit at high tide, rather than low, their
fate would have been far worse.
What worries Bay Area experts is a rupture of a different fault, which would
send waves our way within four to five hours. This worrisome fault, called
the Alaska-Aleutians subduction |
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