This view is looking south from Springmaid Beach toward Myrtle Beach State Park, January 15, 2009. Arrows indicate the debris lines marking the highest points of the last five successive high tides, from right to left.
During January 2009, the full moon occurred on the 10th day of the month. On that occasion, the earth, moon, and sun are all aligned, which creates the maximum gravitational pull on the tides. These higher high tides (which occur at both new moon and full moon) are called “spring tides.” The above photograph was taken five days later, during calm, cold weather, so the seas are fairly placid and steady. During this period, as the moon orbits the earth and moves from full moon toward last quarter (on the 17th), the gravitational pull on the tides steadily lessens.
The photograph shows the receding tide line over five successive high tides. At this evenly-sloping section of beach, the resulting debris piles (known as “drift lines” or “wrack lines,” on this day made up mainly of seashells) are seen to be almost parallel, each about 12 feet farther down the beach than the last one.
It is fairly unusual to see this many undisturbed high-tide lines on the beach at one time. Usually, due to the moon's positions or heavy seas, a high tide will erase the evidence of most of its predecessors.
See an example of an extemely high tide in the article “A Visitor with Pull.”
This guide to Myrtle Beach is sponsored by Mitchells Publications.
Copyright © 2009 Patricia B. Mitchell.