Ocean waves are getting stronger due to global warming. Indeed, According to a new study published in Nature Communications, with the participation of the University of Cantabria, which warns of these aggravating effects of sea level rise in coastal areas, wave power, has increased around the world over the years, with a direct association between the warming of the sea and the increase in wave strength .
A wide range of trends and long-term projections carry the fingerprint of climate change, including sea level rise, rising global temperatures and decrease in sea ice. Indeed, The analyzes of the global marine climate until now have identified increases in the wind speed and the height of the waves in localized areas of the ocean in the high latitudes of both hemispheres. These increases have been greater for the more extreme values than for the average conditions. However, a global signal of change and a correlation between localized increases in wave heights and global warming had not been detected.
The new study focused on the energy contained in ocean waves, which is transmitted from the wind and transformed into wave motion. This metric, called wave power, increased in direct association with the historical warming of the ocean surface. The warming of the upper ocean, measured as a rising trend in sea surface temperatures, influenced global wind patterns, and this, in turn, is making ocean waves stronger.
“For the first time, we have identified a global signal of the effect of global warming on wave climate. In fact, wave power increased globally by 0.4 percent per year since 1948, and this increase is related to the increase of sea surface temperatures, both globally and in oceanic regions,” said lead author Borja G. Reguero, a researcher at the Institute of Marine Sciences at the University of California, Santa Cruz.
Climate change is changing the oceans in different ways, including changes in ocean-atmosphere circulation and water heating, according to co-author Iñigo J. Losada, director of research at the Institute of Environmental Hydraulics at the University of Cantabria in Spain, where the study was conducted.
“This study shows that global wave energy can be a potentially valuable indicator of global warming, similar to the concentration of carbon dioxide, the rise in global sea level or the global surface atmospheric temperature,” said Losada.
Understanding how ocean wave energy responds to ocean warming has important implications for coastal communities, such as the anticipation of impacts on infrastructure, coastal cities and small island states.
Ocean waves determine where people build infrastructure, such as ports, or require protection through coastal defenses, such as breakwaters and dykes. In fact, the action of the waves is one of the main drivers of coastal change and floods, and as the wave energy increases, its effects can be more profound. The rise in sea level will further aggravate these effects by allowing more wave energy to reach the coast.
While the study reveals a long-term trend of increased wave energy, the effects of this increase are particularly evident during the seasons of more energy storms, as occurred during the winter of 2013-14 in the North Atlantic, when the west coast of Europe was impacted; or the devastating 2017 hurricane season in the Caribbean, which offered a stark reminder of the destructive power and economic impacts of coastal storms.
The effects of climate change will be particularly noticeable on the coast, where humans and oceans meet, according to co-author Fernando J. Méndez, an associate professor at the University of Cantabria.