Ocean Energy Surge - Tsunami Day

Even if you've never heard a tsunami warning siren ever before, you know what you're hearing when it sounds.  At 6 AM this morning, I heard the long warning signal oscillating around the surrounding valley of Manoa uphill from Waikiki Beach area.  Simultaneously, all over the Hawaiian Island chain, the same signal was wailing in its odd distinctive way.  We heard neighbors turning on their news channels and checking for information.

You know by now that Santiago, Chile, has been stricken by an outrageously powerful earthquake. Immediately, energy waves began to travel out across the Pacific Ocean to all points on its rim.  This island chain was, of course, situated in a direct path from the shore of Chile.  Hawaii had been crunched in 1960 when Chile was whacked by an even stronger quake.  Back in those days, no warning system like ours today existed, so phone calls, telegrams, radio (HAM radio operators, no doubt) passed information around.  The warnings were scoffed at, unfortunately, and Hilo took a big hit from a series of swells caused by that quake.

Once a month or so, here in Hawaii, the locals hear the siren go off as a practice, rather like the familiar Emergency Signal that is broadcast on TV as practice for disasters.

This morning, the claxon sound was repeated every hour from 6 AM to 11 AM because the surges from the earthquake were to begin arriving at about 11:20 AM, local time.

Like most folks in the area, we decided to go to the local Safeway store and get some groceries, not because we believed the waves would cause significant damage but because we needed to stock up in general.  We found the shopping center in Manoa to be filled with people bustling around or just hanging out, drinking coffee at the local coffee bar and talking.  Inside Safeway, it was very busy.  No one looked panicked or stressed, but the level of industry and alert was more evident than ever before.  After making our selections, we passed the bread aisle.  99% of it was gone.  So, the wisdom of the day is:  Tsunami coming?  Buy bread!

Back at home, we watched the local news stations breathlessly describing the scenes they were showing, and all of them were from very shaky hand-held laptops with cameras and Skype connections.  Friends were dropping by and pretty soon the living room was full of about 10 of us watching for anything that might suggest a threatening wave.  Nothing.  It was a nonevent, and everyone went home again after a few hours of joking and laughing, lounging around at our impromptu tsunami party.

We did learn about the unique characteristics of the a "tidal wave."  The ocean acts very differently with that kind of energy phenomenon.  The wave incidence is much greater; the waves appear to form in very slow motion, beginning with water actually flowing away from shore and then reversing in a large wide swell that flows back onshore.  The onshore flow continues for many minutes --10 or 15 or 20, depending on the impulse of energy that was originally generated by the quake -- and then flows out again.  The outflow takes another long, long period of time because such a massive amount of water is moved by the surge, and stuff onshore that was inundated by the water incoming is then carried out to sea - for a long time.  So, the pattern is:  Long flow out to sea, long period of time of water swelling in, then swoop back out to sea including debris.  Repeat for five or six hours, in and out, back and forth.

Next time you're in a bathtub, make your own tsunami and watch how the water behaves.  Move your leg to the side when it's underwater and watch the water pulling down behind it and then rebounding back and forth.  Same thing happens in God's big bathtub we call the Pacific, or any other ocean.  Lakes, too.

There was indeed tsunami action here today, but the height of the wave surges that finally arrived were very small.  Funneling harbor openings were where the surge was most visible, probably four to six feet from trough to wave crest.

The all-clear was sounded by 2 PM or so.  The quiet streets and highways refilled with cars and the waves with surfers.  We watched the wave riders of all sorts from the overlook below Diamond Head along the coast road.  There were hundreds people on boards all along the coastline, lining up for the beautiful curling waves coming in from the southwest far below us and out as far as a half mile off the shore.  Just the kind of view that the disaster planning had hoped to produce:  Everyone safe; no damage at all.