Fundy Tidal Seiche EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Each day 100 billion tons of seawater flows in and out of the Bay of Fundy during one tide cycle, which is more than the combined flow of all of the world’s freshwater rivers! This can be easily be observed from the Deer Island Ferry.
The Bay of Fundy is the northern terminus of the larger Gulf of Maine and separates southern New Brunswick from Nova Scotia. The Bay of Fundy is a 170-mile-long (270km), straight-sided, somewhat funnel-shaped bay, which splits at its northeastern head into two narrow bays, Chignecto Bay and the Minas Basin. It was formed as the continental plates parted millions of years ago. As they split, deep rift valleys formed, which quickly filled with sediment washed in from the land. The Bay of Fundy is one of these ancient rifts. It is one of the natural wonders of the world. The physical features of the bay are truly amazing. Twice a day 100 billion tons of water rush into and then out of the bay. The bay is wide and deep at the mouth, and shallow and narrow at the head. As this enormous volume of water moves up the bay, a funnel effect amplifies the tides, which range from 3.5 meters or 11 feet at the mouth to 16 meters or 53 feet in Minas Basin at the head. A contributing factor to the tidal amplitude is the length of the Bay. The time it takes a tidal wave to move from the mouth of the bay to the head and back is almost exactly the same as the lunar tidal cycle. This forms a resonant wave called a "seiche" that adds to the already massive tides. This means that the tides range is amplified, similar to the effect produced by children sloshing water into waves in a bathtub. These two factors, combined with several other lunar features, make the tides of the Bay of Fundy a natural wonder of the world.
The Guinness Book of World Records states the world's highest tides to be in the Minas Basin, N.S., with the maximum tidal range recorded at 16.8 meters (54.6 ft). You can see two extraordinary high and low tides every 24 hours. The time between a high tide and a low tide is, on average, six hours and 13 minutes. High tide and low tide are never at the same time every day. The time of the tide changes from day to day because of the revolution of the moon around the earth. It takes 28 days for the moon to travel around the earth and it takes 24 hours for the earth to make one full rotation. By the time the earth makes one rotation, the moon has moved a little further (1/28) along its orbit around the earth. This means that the bulges of water formed by the moon follow as well, as a result it takes approximately 1 hour or more accurately 52 minutes, for a specific spot on the earth to catch up to the high tide bulges. Therefore the time of high tide tomorrow will be approximately 1 hour later than the time of high tide today.
As such, you can reasonably expect to see at least one high and one low tide during daylight hours. Tide times move ahead approximately one hour each day, and tide times vary slightly for different locations around the Bay. Remember tides are created by the gravitational pull of the moon. As the moon revolves around the earth it causes large bodies of water to bulge or pull slightly in the moon's direction. This bulge, as it moves around the globe results in the rising and falling of the tides. The alignment of other terrestrial bodies such as the sun with the moon can affect the amplitude of the tides as well. Accordingly, during a full and new moon, the tides are the highest. And during solstice time period, there is an extra high tide. The powerful scouring action of the Bay of Fundy tides creates a striking coastline. Consider the erosive effect of 14 billion tons of water moving in and out of the Bay twice every 25 hours. It has sculpted spectacular cliffs, sea stacks and caves.
While there are many ways to approach this earthcache the best is generally to use the Deer Island Ferry. The posted coordinates bring you to a location where the Islands block the regular flow of water. Depending on the time you are at the location the water maybe be moving from the west or from the east or not at all. To log this Earthcache: You must post a photo of you and your GPS with a view of the Islands and then send an e-mail describing your estimate of how high the tide is using the water mark along the shore also include the direction of water movement. You should be able to compare your tide time guess to the real tide time by looking at the local tide tables located in most stores and marinas in the area. Please begin your e-mail with the name of the earthcache and make sure your log includes the number of people in your group.
Remember this is an earthcache so there is no container just an earth science lesson at an amazing natural feature. In your log please take the time to describe what you find special about this beach.
Additional Hints
(Decrypt)
Qb vg sebz gur Qrre Vfynaq Sreel