Seiche Wave Corner

New Bern, NC

Well the big bad weather front that passed us last night turned out to be a non event.   The wind blew like crazy all day long from the south.   That hit Tarwathie on the side hard enough that Libby had to free the gimbals on the stove to keep supper from sliding off the top.  When we are at anchor, the wind is always from the front; never from the side for very long.  We're not used to that.

We feared lightning, and tornadoes.  The front looked very ugly on the Doppler Radar.  But when it passed, the wind shifted from 30 S to 40 W and it rained, nothing more.

More dramatic was when I went ashore this morning.  The water levels had dropped three feet.   Other times since staying here we've seen the levels rise three feet.  So I guess the variations are six feet or more.  For a place with essentially zero tide, that's remarkable.  10 hours later it had recovered one foot.

Presumably, when I was seeing -3 foot levels here in New Bern, the water levels up by Elizabeth City were +3 feet.



The technical term for that is a seiche wave.  A wave enclosed by a bounded perimeter. The longest natural period for a seiche in an enclosed rectangular body of water is usually represented by Merian's formula:

  

where T is the period, L is the length, h is the depth, and g is the gravitational constant.  Consider Pamlico Sound plus the Neuse River as a rectangle (it is far from that shape but I don't have the formula for any other shapes.)    That gives a seiche wave period of about 6 miles.   What does that mean? I don't know, it doesn't seem to relate to anything I see.   Below is a plot of a big seiche on Lake Erie.  That's pretty dramatic with a 14 foot difference between Buffalo and Toledo.

Strange Sights and Sounds

New Bern, NC

 

We are back on the boat after nearly 2 weeks on shore. Yesterday it was 72 degrees and today it will be 75, but this afternoon it will blow 45 and winter weather will return. Brrrrr

Last night, about an hour after sunset, I was up on deck. I heard a very strange loud sound. I looked all around, especially up in the sky, and saw nothing. A few seconds later I turned around and saw a huge disturbance in the water. It looked like the continent of Atlantis was trying to surface. OK, now is the time to insert the Twilight Zone theme music. I couldn't figure out the cause. A minute or two later I heard the noise again. I whipped my head around in time to see it. It was an incredibly dense school of fish who were getting excited about something. Wow! We have never seen anything quite like that in nearly eight years on the water.

Then I noticed another coincidence. A brilliant and nearly full orange moon was rising in the East. Then I remembered some local history that I read recently. It was about the native Indians who taught the black watermen how to fish the North Carolina inland waters. One key trick they taught them was which moon brought in the annual schools of shad, and which moon brought the schools of menhaden. I don't know which kind of fish it was last night. I bet that some blog reader could tell me. Anyhow, I now think that the time of year, the full moon and the appearance of that school of fish are a pattern, not a coincidence. Awesome!!!

That 50 foot wide school of fish was so impressive. My mind boggles at the thought of the enormous schools that populated these waters in colonial times. My they must have been impressive. My mind also boggles at the accounts of dinner plate sized oysters. How sad it is that the pressure of seven billion people on this planet has so drastically suppressed other species.

At Sea in Winter

Zebulon, NC

 

It is really cold and windy here today. Brrrrrrrr. Libby and I have no cold tolerance left. The cold wind seems to cut like a knife.

Just for fun, I looked up the marine weather. Out by Frying Pan Shoals, in addition to cold, the winds are 30-40 knots and the seas 18-20 feet. It will stay like that for 4 days. Man oh man does that should horrible. I imagine being out there in our open cockpit. No thank you.

It makes me appreciate more that the sailors of fore were a different breed of men than I or most of m contemporaries. Think of all those men who rounded Cape Horn. Of course part of their secret was that they didn't do it when they were 68 years old. Still, their fortitude was amazing.

If you would like to read a realistic account of what it was really like for those men in 1840, try one of my all time favorite books. "Two Years Before The Mast" by Richard Henry Dana. His account and his English sound modern , so the reading is easy. You can get a free copy here.

 

Winterizing Run

Zebulon, NC


I screwed up. [I can hear the readers now.  "What's new about that Dick?"]   I regularly skip articles about winterizing boats, smug in the certainty that it is a subject I'll never need to worry about.   Now I regret that.

Yesderady Libby and I listened to the New Bern weather report.  It called for overnight lows of 19F, and subfreezing.   They said it will be the coldest night in NC in many years.  YIPES!  I have no anti-freeze solution in the raw water part of the cooling system.   What should I do?   On one hand, the engine would probably be OK.   Even if air temperatures are below 19F, the river temperatures are above 32F.   But am I confident enough in that to take the risk?  No.

So last night I drove 218 miles in a round trip to New Bern, just to put anti-freeze in the engine and in the head.    I really regret not having done that before leaving the boat.

Who was it that said, "Merely owning a car leads one to making unnecessary trips."  How true.

Away from the Boat

Zebulon, NC

We are spending two weeks away from the boat.  In part we are house/dog sitting as Dave & Cathy take off for a weeks vacation.   As usual, when away from the boat my blogging activities are much reduced.

Below you'll find a post called Frajectives.  It is a piece I wrote that I'm particularly proud of.  I think it is good writing.   But alas, I submitted it to the NY Times with no reply.  I submitted it to the Washington Post and they rejected it.

Obviously, I'm fond of writing.  At the same time, I'm put off by the hassles of getting something published.   I don't mind rejections but I get really frosted at the usual result of no reply at all.  I'm also impatient.  I wrote a neat article suitable for boating magazines recently and sent it in.  I was shocked to find, for example, that Cruising World is fully booked for 2013 and that the delay to get published is closer to 18 months.  Some of what I wrote would be seriously dated by than.  

So, I guess I'll stick more with this blog.  It suits me better, and I hope that it entertains a few people out there.