Tide Clock Tips

Tide Clock Tips
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Part of the fun of writing product blogs is the opportunity to do research on line.   No longer do I have to consult my 12 volume encyclopedia or visit the library to check out books and scan microfiche.  The internet is an amazing resource.  I Googled YouTube videos to learn more about the science behind the operation of tide clocks, and you won’t believe how many short video clips are available to view on the subject of tides.  Many are created by middle school science class students and they are very good. Some are more professional videos produced by reputed organizations like NASA and other educational institutions.  I’ve posted a few short videos below that I found instructive and creative on the topic of lunar tides.






It helps to have a basic understanding of how the moon affects our oceans in order to understand how tide clocks work.  Probably the most frequently asked question relating to these clocks is: “Once I set my clock to the correct tide will I ever have to reset it?”  The answer is YES, usually. And here is why!

The intervals between tides depends on the position of the moon, the sun and where on the earth you are. The clock keeps track of the moon’s “apparent” motion around the earth. The moon travels through the sky around the earth in 24 hours, 50.5 minutes.  A tide clock is divided into two six hour long tidal periods that shows the average length of time between high and low tide in a semi-diurnal tide region such as most areas of the Atlantic Ocean. The fluctuation rhythm of the tide is between 12 and 13 hours. Therefore, the tide clock gains approximately 15 minutes per month and depending on where you are it might need to be adjusted occasionally. If your tide clock is on a boat and the boat is on the move you will need to reset the clock more frequently.

Another thing to understand is that the tide phases are more regular on the East Coast of the United States than on the West Coast because the Atlantic Ocean is a smaller body of water than the Pacific Ocean, and so the tides are more uniform and regular. If you live on the East Coast you really never have to adjust the tide clock, but those who use a tide clock on the Pacific Ocean will have to readjust the tide setting as often as weekly. And if you live on the Gulf of Mexico tide clocks don’t work at all because the tide is diurnal – only one high and one low tide a day.

Here is a map of the types of tides on the coastlines of the world:

Map of tides

These two websites are a wealth of information for those who would like to learn more about how the moon affects the earth’s tides.



Did you know that Tide clocks have only been around since 1971? It was in 325BC that the famous Greek explorer, Pytheas, hypothesized that the moon was the cause of tidal changes.  And then in another 2000 years, in the 17th Century, Newton came up with a definite theory about how the moon pushed and pulled the oceans on the face of the earth. Even in today’s high tech world its amazing to think that the moon has such a strong effect on the earth.

Since the 1970‘s  many different kinds of tide clocks have been developed.  Weems & Plath has a variety of styles, some incorporate tide and time in the same instrument. This means that along with the standard quartz clock movement there is also a tide clock mechanism inside the instrument. Plus, on the face of the clock, there is an additional red hand that points to the tide level.  High tide is shown at the 12 o’clock position and low tide is at the 6 o’clock position. Using the adjustment knob located on the back of the instrument set the tide using Official Tide Tables for your area at either high or low tide.

It should be noted that variables such as wind, atmospheric pressure, the relative position of the moon, and the elliptical pattern of the sun will affect the tide slightly. These phenomenon least affect the tide at the time of the full moon. For this reason, the time of the full moon and to a lesser extent, the new moon are generally the best times to set your tide clock.

Weems and Plath offers a collection of instruments that includes a unique tide clock that displays a thermometer and hygrometer along with the tide feature.  The Veranda Tide clock is more appropriate for mounting on a fence post or window trim than on a boat. Any seaside home or business should have one.  It features two different mounting methods depending on the placement of the instrument.

The Veranda Collection also includes a Time & Tide Clock with thermometer and hygrometer – Four instruments in one!  Please visit the Weems & Plath website to learn more about the many time and tide clocks that we offer. If you are a boater, sailor, surfer, fisherman, beachcomber or seaside homeowner a tide clock is a necessary tool.

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