They say, “it’s a small word”—well, there is some truth behind the saying.
A tropical storm, originating near the Pitcairn Islands in the Southern Pacific, created some 50ft waves during its peak strength on June 29th, 2014. The storm gained its status within 24 hours after its first appearance as a Tropical Depression Four-E. The waves it created traveled across the Pacific Ocean, and arrived at the northeast Pacific coast. A few days later, during the fourth of July weekend, monstrous swells bombarded Southern California, including our owns White’s Landing.
Waves created by storms move across the ocean at a certain speed depending on the strength of the disturbance. Waves that have the same speed eventually synchronize as they travel, generating series of swell like ripples. Energy in the waves dissipates as they travel, and their wave height also reduces. A wave’s trough begins to touch the seafloor as it comes closer to the coast, pushing it upwards and increasing its height again, then they begin to break and collapse in the surf zone. A 10ft wave in the open ocean may become 15ft tall as it crashes on shore. Since the tropical storm originated in the Southern Ocean, south-facing coves were most susceptible to great swell and the damages that it brought along.
But hold on! The White’s Landing cove isn’t south-facing, so why was it not spared?
Good catch there! Here comes the science of reflection and refraction. First, swells that hit the mainland reflected directly back into the ocean. Santa Catalina Island is located just 26 miles southwest of the mainland, therefore, the north-facing side of the island, including White’s Landing, received any swells that had bounced back, or reflected, from the coastline.
Second, San Clemente Island, which is directly south of Santa Catalina Island, refracted swells that came across from the Southern Ocean. As the swells passed the southeast point of San Clemente Island, the swells were refracted and propelled in a northwest direction towards Avalon. The swell yet refracted again near Avalon Bay when it reached Santa Catalina Island, sending them directly towards White’s Landing, and this is why we received the bombardment even though White’s cove is sheltered from the Southern Ocean.
The damages to the pier were serious. Because the floating dock was damaged and sections of the pier were wiped out, we were forced to close it down. Groups that were here had to hike 3.5 miles to the Airport Road where they were loaded into busses and sent to Avalon to board a ferry to the mainland. Others that were scheduled for the week of July 6th had to cancel their summer camp experience at Whites Landing.
However, as devastating as it looks, TCX-ers had already begun the repairs and re-construction, putting things back in order. Some of us dove down to retrieve pieces of the ramp and float, some tried to untangle the kelp mess around ropes and lines underneath the pier, and some filled the holes and missing wood on the walk. With everyone working full power, the maintenance work was completed in just 4 days!
The ocean is now as calm and tranquil as ever. Murky, beige water that robbed the beach began to recede as the sediment once again precipitated to the bottom. Who would have thought that waves measuring 15 feet tall had paid a visit just a short time ago? In no time, new caves dug by the perilous swells will be echoing with the joyous laughter of our next camping group. As for those foreign swells, they will become part of our Catalina experience.
Posted by Rhyn Cheung, Program Specialist