Southern Ocean Wave Heights Up By 1 Foot 1985-2018; Wave Energy Up By 8% Since The 1980s
EDIT
Between 1985 and 2018 wave heights in the Southern Ocean increased by 30 centimetres, or around a centimetre a year. Because waves from the Southern Ocean propagate out into the Pacific, South Atlantic and Indian Ocean, this has contributed to increases in wave size there as well. Wave energy is increasing as well, ticking up around 8% since the 1980s, with the rate of change accelerating markedly since the turn of the century, reflecting not just changes in wave height, but also increasingly intense storms and more frequent extreme wave events.
Research by Hemer and his colleagues predicts that without significant cuts in carbon emissions this process will continue, although these changes are not consistent across different regions: wave height in the North Pacific and North Atlantic may actually decrease.
Ian Young is Kernot professor of engineering at the University of Melbourne. His research shows that by 2100 about 60% of the world’s coastline will experience larger and more frequent extreme waves, and predicts that without drastic reductions in emissions extreme sea level events could increase tenfold or even more by the end of the century, and coastal flooding could strip as much as 20% off the value of the world economy. And while the “the biggest issue is mean sea level rise … breaking wave setup can account for up to 20% of the flooding.”
Events like the storm that swept away about 25 metres of the coastline at Narrabeen and Collaroy on Sydney’s Northern Beaches, depositing a swimming pool on the beach and leaving houses hanging off cliffs, clearly demonstrate the effects of larger and more powerful waves on coastlines and coastal communities, especially in combination with rising sea levels. Larger waves have also contributed to disastrous flooding events on a number of Pacific islands, helped strip hundreds of metres of sand from beaches and accelerated the retreat of cliffs in south-west England and France, and are helping accelerate the disastrous effects of melting permafrost and rising sea levels on vulnerable communities in the Arctic, where coastlines are already retreating many metres a year.
EDIT
https://www.theguardian.com/environment/2025/feb/22/waves-are-getting-bigger-is-the-world-ready