Lower Manzanilla residents were left in shock and disbelief one morning in April by the sight that lay before them on the beach: the aftermath of the crashing sound of waves heard roaring through the night. There was a line of uprooted fully-grown coconut trees laying on the ground along with a plethora of Sargassum muticum, commonly referred to as seaweed, stretching for miles along the southeast coastline.
The sea defenses of carefully placed rubber tires, embankments and concrete walls, which many of the private property owners used to protect their homes, were no match for the phenomenal King-Tide that emerged that weekend. Tires were scattered everywhere, huge sections of embankments eroded and chunks of concrete walls collapsed by the force of the tide.
One resident, Mr. Curt Delandro, a retired Army/Prison Officer, said he had never seen this occur for the 51 years that he has lived in the area. He said the waves normally break further away from the existing shoreline and reminisced about the days he had an extra 10 meters of property to occupy. Delandro states that had it not been for a cluster of sea grape trees, (coccoloba uvifera) which were sporadically placed on the perimeter of his property before the shoreline, he certainly would have lost more land to erosion over the years.
So, what was this fury? This assault of nature? Many of the Manzan residents believe it was due to the supermoon. The term “supermoon” was coined by the astrologer Richard Nolle in 1979 and refers to either a new or full moon that occurs when the moon is within 90% perigee, its closest approach to earth.
Since we cannot see a new moon except when it eclipses the sun—what catches the public’s attention are the full supermoons, as this is when the full moon appears biggest and brightest for the year. Supermoons have become popular over the last few decades. In a typical year, there can be two to four full supermoons in a row and two to four new supermoons in a row.
The April full moon was the first of two supermoons for 2021. The other supermoon was May and the moon will appear full for about three days. King Spring Tides –higher than average high tides and lower than average low tides– typically occur with the supermoons and form part of a natural cycle. By Tuesday, all was quiet in Lower Manzanilla after the phenomenal high tide. There were no drastic changes in tidal action at this time, and property owners were up and about discussing how to repair the damage.
Scientists at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science (RSMAS) have reported that “these supermoons have a twist—as they represent the most rapid downward phase of the 18.6 years’ lunar nodal cycle and is believed to reprieve the observed rate of sea-level as it lessens the moon influence on the oceans”. That being said, RSMAS reports that the next 18.6 years’ lunar nodal cycle will be more closely aligned with the plane of Earth’s equator, hence increasing tidal fluctuations.
Dr. Linton Arneaud—Environmental Biologist at Banks Village Environmental Organization (BVEO) acknowledged that there were no known reports of coastal damage in other parts of Trinidad and Tobago. This led him to speculate that the high ocean currents or any other sporadic hazardous sea event along the Manzanilla shoreline may have coincided with the pink moon.
As a result, the next lunar nodal cycle guarantees that sea level is expected to rise, and coastal property owners throughout the globe, including Mr. Delandro and his neighbors here in Trinidad and Tobago, need to be prepared for an acceleration in sea-level rise.
Most property owners and residents along Manzanilla’s coastline are struggling to protect their beachfront properties. To this end, the BVEO team of professionals, who happened to be on a field mission in April, were asked for advice and an intervention by the affected residents. Some residents spoke of wanting to use hard engineering structures like riprap revetments, similar to what was implemented on the shoreline by the Coastal Protection Unit of the Ministry of Works and Transport, further along the Manzanilla coastline. However, they were forced to acknowledge that this method is costly.
The BVEO team also explained to the residents that over time, hard structures can lead to further erosion and require maintenance, especially if not installed properly. Other engineering structures such as old tires and debris will only contribute to further coastal pollution and should be avoided altogether.
The BVEO, however, sympathized with the property owners’ concerns that private construction works in the area were blocking naturally occurring waterways along the coast which would increase freshwater flooding—in particular, during the hurricane season, contributing to coastal erosion.
To address their concerns, the BVEO team advised using a more integrated coastal management strategy that involves the use of suitable plants, referred to as “living shorelines” to reduce erosion, lower costs and increase the value of their property.
BVEO will provide an update on the community’s efforts.