Chile 8.8 Earthquake - Tsunami Warning

[Alex]

http://www.hawaiinewsnow.com/Global/category.asp?C=176904&nav=menu55_1_1

[Alex]

Earthquake in Chile shakes Lake Ponchartrain

Lake Ponchartrain was shaken and stirred early this morning by a massive earthquake in Chile.

"There was some sloshing of Lake Ponchartrain between about 4am and 4:30 this morning, our time. We had some, about half-a-foot slosh spikes near Shell Beach and that basically went on for about a half hour,' says Scott Lawrimore, with The Weather Channel.

Besides the Shell Beach area, the sloshing was also noticeable at Pass Manchac and West End in Metairie.

Lawrimore said the effect is like water being shaken in a bottle.

"The earthquake that occurred in the Pacific basically vibrated the earth enough here in Louisiana so that Lake Ponchartrain felt that...just like you would if you picked up a bucket of water and shook it back and forth," says Lawrimore.

"While that earthquake was occurring in the Pacific Ocean, even though it was not really detected by us, there was enough back and forth motion in the earth to produce sloshing back and forth in Lake Ponchartrain. And that sloshing resulted in about a half-a-foot slosh spike," Lawrimore said.

just correcting a typo in the subject...

[Alex]

Portions of Interstate H1 are closed.

[Alex]

Closed sections of Hawaii 72 east of Honolulu.

[oscar]

The tsunami warnings and evacuation orders in Hawaii are still in effect until the waters calm down, but the tsunami seems to have spared Hawaii, with minimal damage (waves a meter high at most).  Hilo was the biggest worry, since it got trashed by another Chilean earthquake in 1960.

The southern Alaska coast has a lower-level tsunami advisory.  Nobody's being told to evacuate to higher ground, people are just advised to stay away from beaches and harbors.

[Chris]

The main problem with these tsunamis is not necessarily their height, but their brute force. It's not like a normal wave which comes and goes in a few seconds. Tsunamis can go on for minutes, because there is a lot more energy. One wave can just come washing ashore while you would think "wouldn't it recede by now?".

Some areas hit by the 2004 Indian Ocean tsunami experienced waves of only a few meters, but those killed thousands, there are a lot of debris in these tsunamis, and you will get pulled to the sea once the wave recedes.

On the open seas, the wave is no problem, there is a chance you won't even notice it. It travels at very high speed, up to 500 - 600 miles per hour (which still takes a day to cross the Pacific), but once it reaches shallow waters, it slows down and begins to increase in height.

Also; tsunamis are measured to the regular sea level, not through-to-crest, which makes it sound they're no big deal, but they can be lethal.

I also read about a 120 feet tsunami hitting some islands far off the coast of Chile yesterday, but I haven't heard about it since.

[Bickendan]

IIRC, earthquake generated tsunamis can't reach 120 feet. Slide generated tsunamis can, though.

[Chris]

I joined a USGS email lest (Earthquake Notification Service). There have been several 6.0 + aftershocks in the past couple of days. Just right now there was a 6.3 which alone could be potentially devastating.

[Chris]

Another 7.2 quake near the Chilean coast.