Kayaking and Tsunami safety questions

Obvious why this is on my mind...
So they tell us if we are at coast and feel ground shake, head to higher ground ASAP.  Time is of the essence.  OK, I can do that. 

But, what if I'm in XYZ Bay?  Can you feel an earthquake sitting in a boat in a bay?  And if you can, would it be better to paddle out to open Ocean and try to let the tsunami pass under you or some other option?  Realize there are a lot of variables here.  Wondering if others have thought about this?  (I suppose the warning sirens would go off so it might not matter if you could feel it but would be nice not to lose the time from event beginning to siren.)

Hopefully you have somewhere to go, as if we have an earthquake off our shore, odds are slim you will have time to beach and run by the time a tsunami hits.  If you are in a bay, heading out to open ocean may be too far to go, too.

If already out in the ocean, I'd probably head further out all while contacting the Coast Guard with my intentions so that afterward they know I am out there and can give me instructions on when to come back in or not.

As for feeling the earthquake while on the water, I doubt that is possible directly.  Probably have to rely on the VHF alert, and or the sirens at the beach.   

BTW - There is an earthquake prediction for this weekend off our coast.   

Hopefully you have somewhere to go, as if we have an earthquake off our shore, odds are slim you will have time to beach and run by the time a tsunami hits.  If you are in a bay, heading out to open ocean may be too far to go, too.

If already out in the ocean, I'd probably head further out all while contacting the Coast Guard with my intentions so that afterward they know I am out there and can give me instructions on when to come back in or not.

As for feeling the earthquake while on the water, I doubt that is possible directly.  Probably have to rely on the VHF alert, and or the sirens at the beach.   

BTW - There is an earthquake prediction for this weekend off our coast.

I'd say this prediction is 100% accurate...sometime between now and March, 2111. 

I can tell you from experience that you can feel an earthquake while out on the water.  I was surfing about a hundred miles south of Ache 4 months after the big Indonesian quake when an 8.1 hit.  It took a moment to figure out why my surfboard suddenly felt like jello.  We made a bee-line for the panga and back to the mothership.  As soon as everyone was aboard we headed for deep water.  The resulting tsunami was small and we never even felt it about the boat but it did some damage to the islands in the area.

If we had a 9.0 while on the water, there would be no doubt in your mind as to what was happening.  I think your only chance would be to paddle like hell for deep water and then paddle some more.   If you made it, you'd probably want to ditch your gear as soon as you hit shore and head for higher ground as reflected waves continue for many hours after the initial tsunami.

-Spot-

Interesting that you could actually feel the quake.  Maybe it transfers like a big sound wave?

I don't know if I'd want to try to make a beach landing with all the potentially sharp pokey things that could be already along the beach.  I was hoping for more of an angel picking me up and gently place me on higher ground.   

I wonder how quickly they announce/update "emergency" information on the VHF weather band, or should you be keeping a watch on ch. 16?

I would think ch. 16 would be full of chatter if a big one hit with lots of people on the water. Panic stricken boaters would not likely practice good VHF etiquette.

http://www.weather.gov/nwr/

I think that with a similar quake and tsunami arivial timing to the recent quake in Japan you would be just plain screwed.  Lets say you were approx 1/2 mile offshore (thats past the rock in PC) it would take you 15 min to get in at least. If it was similar to the timing of the tsunami in japan you would be hitting the sand and in the zone at about the time it showed up even if you started paddling in the minute you heard the sirens, not to mention getting yourself out of the tsunami zone once you hit dry land.  As for heading the other direction I not sure how far out you would need to go to be safe and when could you know to head back home and miss and refracted or secondary waves.   I don't think a paddler could get far enough out fast enough to save your bacon....  Wheres the Myth Busters when you need them

OK, question submitted to Mythbusters. ... guess we wait and see what turns up.

I think Spot is: Spot on???

If I was off the beach already I would head for deep water as fast as I could. Tsunamis, in open water, are not all that high but have a very long frequency from peak to peak. Those peaks also travel very quickly. As they approach shallows, the peaks slow down and get compressed closer together, and in compensation the peaks pile up higher as they approach the beach. In effect, out in open water with sufficient depth, the peak may rise only 5', but as it approaches land it may rear it's head to something closer to 30'. Notice that all the damage along the west coast of North America occurred in harbors, which are relatively shallow. Most of the destructive force was related to the surging in and out of the harbors.

If I was already in a harbor, lets say Tillamook Bay, I'd probably try and hang out in the niddle and avoid the debris and bores as much as possible. I thinbk being on the shore would be the worst possible place to be, when the surge actually occurs.

Check out this video of the incoming Japanese tsunami wave.  You're pretty much toast. 

The answer is head further out. 

From USGS

Except for the largest tsunamis, such as the 2004 Indian Ocean event, most tsunamis do not result in giant breaking waves (like normal surf waves at the beach that curl over as they approach shore). Rather, they come in much like very strong and fast-moving tides (i.e., strong surges and rapid changes in sea level). Much of the damage inflicted by tsunamis is caused by strong currents and floating debris. The small number of tsunamis that do break often form vertical walls of turbulent water called bores. Tsunamis will often travel much farther inland than normal waves.

If you're in a bay, and manage to get away from the incoming wave/surge damage, don't stop, keep heading OUT, because there will be an outflow afterwards that will be full of debris.

If you're already in deep water, chances are, you won't have any problems at all.

Hope to be a couple miles out, the wave starts to break much earlier than regular waves, and is a bout a 30-foot deep wall of foam

I think for those of us in fjords like areas, we'd just be toast,  It's deep...but narrow.  That's something to research.  Does it matter that you are in 1,000 ft of water if you are in a fjord only 2 miles wide? I wonder about Puget Sound?  I know the towns at the terminus of the fjords got wiped out but that's to be expected.  Do we have hydrologist in the room?


http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=whittier,+ak&aq=&sll=40.513799,-101.25&sspn=43.795925,107.226563&ie=UTF8&hq=&hnear=Whittier,+Valdez-Cordova,+Alaska&ll=60.736008,-148.439713&spn=0.221868,0.837708&z=11http://aesrv/CRM/eware.dll/go

I don't care how far out you are, you're still gonna pucker up for this one




so far as the fjords, i'm pretty sure the confines of the fjords have been known to magnify tsunami effect. i suppose it really depends on the direction it travels.  In a video i saw back in 2005, it was suggested that the largest tsunamis were caused by landslides at the terminus of fjords...

so far as the fjords, i'm pretty sure the confines of the fjords have been known to magnify tsunami effect. i suppose it really depends on the direction it travels.  In a video i saw back in 2005, it was suggested that the largest tsunamis were caused by landslides at the terminus of fjords...

If I recall those are caused by mountain sides collapsing into the sea and creating waves to and beyond 1000' high.  There is one setting up in the Canary Islands which when it goes will initially create a wave 3000' high and send a tsunami more than 100' high across the Atlantic wiping out most of the US Eastern seaboard. 

http://en.wikipedia.org/wiki/Megatsunami