12 may 2018
A MetOcean Solutions wave buoy moored in the Southern Ocean recorded a 23.8-meter (78.1-foot) wave on May 8. Senior Oceanographer Dr. Tom Durrant says it is believed to be the largest wave ever recorded in the southern hemisphere.
The company’s previous record was one year ago when the buoy measured a 19.4-meter (63.7-foot) wave. Before that, in 2012, an Australian buoy recorded a maximum individual wave (Hmax) of 22.03 meters (72.3 feet).
The significant wave height, approximately the average of the highest third of the measured waves, reached 14.9 meters (48.9 feet). This was also a record for the Southern Ocean, but fell short of the 19-meter (62.3-foot) world record buoy measurement that was recorded in the North Atlantic during 2013.
Durrant says the May 8 storm could have resulted in waves over 25 meters. “The wave forecast for the storm show larger wave conditions just north of the buoy location. Also, to conserve battery during the one year deployment, the solar-powered buoy samples the waves for just 20 minutes every three hours then sends the data via a satellite link. During that 20 minute recording period, the height, period and direction of every wave is measured and statistics are calculated. It’s very probable that larger waves occurred while the buoy was not recording.”
The Southern Ocean is a unique ocean basin and is the least studied despite occupying 22 percent of the global ocean area. The persistent and energetic wind conditions create enormous fetch for wave growth, making the Southern Ocean the engine room for generating swell waves that then propagate throughout the planet.
“Surfers in California can expect energy from this storm to arrive at their shores in about a weeks time,” says Durrant. “The storm is the perfect example of waves generated by the easterly passage of a deep low pressure system with associated wind speeds exceeding 65 knots. Such storms are frequent and can occur at any time of the year, which differs from the high latitude northern hemisphere storms that only occur in winter. What is interesting about May 8’s event is the storm speed appears to match the wave speed, allowing wave heights to grow dramatically as the system tracks eastward.”