Medical News Extremely fast winds and high waves are now happening more often
25 April 2019
Extreme waves are happening more frequently in the Southern OceanLook/Alamy Stock Photo
By Adam VaughanExtreme winds and waves have increased globally over the past three decades, exacerbating the flooding threat to coastal communities during storms.
There has also been a small but significant strengthening in average wind speeds and wave heights between 1985 and 2018 in some regions.
Ian Young at the University of Melbourne and colleagues analysed data from 31 different satellites, which provided a much bigger dataset than previous efforts to measure changes in wind speed and wave height.
They found changes were most pronounced in the Southern Ocean, where extreme wind speeds increased by 8 per cent and extreme waves by 5 per cent over the period.
While the Southern Ocean may seem remote for many people, it is where ocean swells are generated which influence wave conditions in the Indian Ocean, southern Atlantic and large parts of the Pacific. Those swells determine how stable beaches are throughout much of the southern hemisphere.
Added to a backdrop of accelerating sea level rises, stronger winds and waves will worsen coastal flooding too.
“If extreme waves are increasing in magnitude, it will further increase the impact of storm-related flooding events and also have major impacts on the erosion of beaches,” says Ian Young at the University of Melbourne, a coauthor of the study.
Higher waves will likely also increase the rate at which ice is broken up, affecting the Antarctic’s vast ice sheet.
The observed strengthening in wind speed and wave height is what some climate change models had expected.
“It seems that climate change is not only affecting the number and the intensity of storms around the world – but also the average windiness and wave heights,” says Mark Maslin of University College London.
Journal reference: Science, DOI: 10.1126/science.aav9527
More on these topics: