Here’s What To Do If You Encounter Square Waves in the Ocean

Many of us enjoy spending summer days at the beach, soaking in the sea and having fun. However, it’s crucial to remain vigilant when surrounded by water. A single misstep can have serious consequences. While we’re familiar with changing tides and rip currents, it’s important to be aware of the dangers posed by square waves.

Also known as cross seas, square waves occur when two or more swells meet at right angles, forming a distinctive checkerboard pattern. According to the European Space Agency (ESA) in 2010, “These conditions are quite common in the ocean when wind seas and swells or two swell systems coexist.” A 2004 study highlighted that a significant number of ship accidents occurred in cross sea states.

Cross seas can generate swells up to 10 feet high and create complex wind patterns, making navigation challenging for boats and swimming hazardous for individuals.

If you encounter square waves, it’s advisable to avoid venturing out on boats or swimming in these turbulent waters. Instead, relax on the shore and wait for safer conditions.

Square waves typically form at the meeting points of oceans or large water bodies, such as peninsulas where different swells converge. Examples include the Isle of Re in France and Cape Reinga in New Zealand, where the Tasman Sea meets the Pacific Ocean.

These locations are not only picturesque but also draw numerous tourists. However, it’s important to admire square waves from a safe distance to avoid risk.

Square waves, created by intersecting swells, are an intriguing example of nonlinear wave dynamics, often described by the Kadomstev-Petviashvili equation. This equation explains how different wave systems interact with each other in the ocean.