4/4/17 Report - Ship Remains Dated to 17th Century. Complexities of Beach Erosion.

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Jupiter Beach.

Jupiter Beach, as you can see above, has tons and tons of new sand.

Thanks to Joe D. for the photo.

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Uncovered Ship Remains Buried Near Alexandria Virginia.
Source: See WTOP link below.

... Skolnik said some of the earliest tree rings from the ship are from 1603 — four years before John Smith showed up in Jamestown and 17 years before the Pilgrims showed up in Massachusetts.

“So the wood in the ship comes from a time of early American history that even predates the earliest permanent English settlements here in the New World,” he said.

But the ship was sunk on purpose by early Alexandrians.

He said documentary records show between 1788 and 1796, the ship went from being a vessel to being buried...

Here is the link for the rest of the article.

http://wtop.com/alexandria/2017/04/uncovering-mystery-behind-alexandria-waterfronts-18th-century-ship/slide/6/

They dated this ship by looking at the tree rings on the lumber.

Notice the number and size of the rods.

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Yesterday I posted a list of ten factors that contribute to beach erosion.  Predicting erosion is complicated by not only the number of factors, but also how quickly those factors can change.  Furthermore, there are interactions.  For example, wave size interacts with tides.  Big waves are most effective when the tides are high.  So the timing of both factors as they relate to each other is important.

Water force is obviously the primary factor that causes sand and other items such as coins to move.  Many of the factors change the force of water at different locations.

The same force of water will move one type of object but not another, therefore you get separation or sifting of objects.

Erosion is a good sign and always present during the very best beach conditions, but beach old coins sometimes appear on the beach when there is no erosion.  I explain that more some day.

One complication is that the direction of water from an individual wave will wash up and then back down the beach, so the force of water from each wave changes direction.  Not only does the direction of the force change, but  the amount of force also changes as the wave goes up and down the beach. That might be obvious enough, but figuring out how the sand and other objects move is more complicated.

Another complication is that each wave interacts with other waves.  The outgoing water from one wave will hit the incoming water from the next wave.  The force from both waves is changed when they interact.  When outgoing water hits the incoming water from the next wave, temporary much of the force is lost at that point.

I'll continue with this some other day.

Here is a little puzzle.

Coins and other objects can actually move in the opposite direction of the water rushing over and around them.  Think about how that might happen.  I actually explained that once before.

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If you have never seen the Northern Lights before, you might want to check it out.  For me, it is something that I'll never forget.

http://blog.spiritdaily.com/news-links/northern-lights-in-real-time

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Yesterday the wind picked up in the afternoon and we had some good southerly winds.  I wish I'd get a chance to get out today to check out one of my spots that gets hit better by southerly winds.  Perhaps tomorrow.

We're supposed to get a cold front later this week.  It doesn't look like it will increase the surf though.

Happy hunting,
TreasureGuide@comcast.net

3/9/16 Report - Shipwrecks, Tree Rings and Hurricane Data.

Here are some excerpts from an interesting article from the University of Arizona News.

... Records of Spanish shipwrecks combined with tree-ring records show the period 1645 to 1715 had the fewest Caribbean hurricanes since 1500, according to new University of Arizona-led research. The study is the first to use shipwrecks as a proxy for hurricane activity...

The 1715 Fleet was just unlucky, I guess.

...The researchers found a 75 percent reduction in the number of Caribbean hurricanes from 1645-1715, a time with little sunspot activity and cool temperatures in the Northern Hemisphere.

Although global climate models indicate hurricanes will be more intense as the climate warms, those models are not yet good at making regional predictions, Trouet said. Learning more about how hurricanes correlated with climate for the past 500 years may lead to better regional predictions of hurricanes.

The new research provides an annual record of Caribbean hurricanes going back to the year 1500 — shortly after Christopher Columbus first reached the Caribbean.

Harley mentioned he had tree-ring records from the Florida Keys that went back to 1707 — and that the tree rings revealed when hurricanes had occurred. The growth of trees is retarded in years with hurricanes. That reduction in growth is reflected in the tree's annual rings.

Domínguez-Delmás, a dendroarchaelogist, figures out when Spanish ships were built by retrieving wood from shipwrecks and dating the wood. Trouet wondered whether the tree-ring record of Florida hurricanes could be combined with shipwreck data to create a long-term history of Caribbean hurricanes.

The books, combined with ship logs, allowed the researchers to compile a list of Spanish ships known to have been wrecked by storms during the hurricane seasons of 1495-1825. The team found that the hurricane patterns from the shipwreck database closely matched Florida Keys tree-ring chronology of hurricanes from 1707-1825.

In addition, the team compared the Florida Keys tree-ring records to the systematic recordings of hurricanes from 1850-2009. Again, the patterns matched.

When they overlapped the shipwreck data with the tree-ring data, the researchers discovered a 75 percent reduction in hurricane activity from 1645-1715, a time period known as the Maunder Minimum.

The Maunder Minimum is so named because there was a low in sunspot activity during that time.

Here is the link if you want to read the entire article.

https://uanews.arizona.edu/story/shipwrecks-tree-rings-reveal-caribbean-hurricanes

At this point I'm not highly confident in the methodology or conclusions, however it is interesting.

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On the Treasure Coast we have a 3 - 4 foot surf and it looks like several days of Southeast winds.

Happy hunting,
TreasureGuide@comcast.net