Upper-ocean warming is changing the global wave climate, making waves stronger

January 14, 2019, University of California - Santa Cruz
Increasing wave energy with climate change means more challenges for coastal risk and adaptation. Credit: IH Cantabria

Sea level rise puts coastal areas at the forefront of the impacts of climate change, but new research shows they face other climate-related threats as well. In a study published January 14 in Nature Communications, researchers report that the energy of ocean waves has been growing globally, and they found a direct association between ocean warming and the increase in wave energy.

A wide range of long-term trends and projections carry the fingerprint of , including rising sea levels, increasing , and declining sea ice. Analyses of the global marine climate thus far have identified increases in wind speeds and wave heights in localized areas of the ocean in the high latitudes of both hemispheres. These increases have been larger for the most extreme values (e.g., winter waves) than for the mean conditions. However, a global signal of change and a correlation between the localized increases in wave heights and global warming had remained undetected.

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, has been increasing in direct association with historical warming of the ocean surface. The upper , measured as a rising trend in sea-surface temperatures, has influenced wind patterns globally, 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 in wave climate. In fact, wave power has increased globally by 0.4 percent per year since 1948, and this increase is correlated with the increasing sea-surface temperatures, both globally and by ocean regions," said lead author Borja G. Reguero, a researcher in the Institute of Marine Sciences at the University of California, Santa Cruz.

Climate change is modifying the oceans in different ways, including changes in -atmosphere circulation and water warming, according to coauthor Inigo J. Losada, director of research at the Environmental Hydraulics Institute at the University of Cantabria (IHCantabria), where the study was developed.

"This study shows that the global wave power can be a potentially valuable indicator of , similarly to carbon dioxide concentration, the global sea level rise, or the global surface atmospheric temperature," Losada said.

Understanding how the energy of responds to oceanic warming has important implications for coastal communities, including anticipating impacts on infrastructure, coastal cities, and small island states. Ocean waves determine where people build infrastructure, such as ports and harbors, or require protection through coastal defenses such as breakwaters and levees. Indeed, wave action is one of the main drivers of coastal change and flooding, and as wave energy increases, its effects can become more profound. Sea level rise will further aggravate these effects by allowing more wave energy to reach shoreward.

While the study reveals a long-term trend of increasing , the effects of this increase are particularly apparent during the most energetic storm seasons, as occurred during the winter of 2013-14 in the North Atlantic, which impacted the west coast of Europe, or the devastating 2017 hurricane season in the Caribbean, which offered a harsh reminder of the destructive power and economic impacts of coastal storms.

The effects of climate change will be particularly noticeable at the coast, where humans and oceans meet, according to coauthor Fernando J. Méndez, associate professor at Universidad de Cantabria. "Our results indicate that risk analysis neglecting the changes in and having as the only driver may underestimate the consequences of climate change and result in insufficient or maladaptation," he said.

Explore further: 2017 was the warmest year on record for the global ocean

More information: Borja G. Reguero et al, A recent increase in global wave power as a consequence of oceanic warming, Nature Communications (2019). DOI: 10.1038/s41467-018-08066-0

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12 comments

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dogbert
2.7 / 5 (7) Jan 14, 2019
Wave power has increased 28% since 1948 and we are just noticing it?

Really?

Laughable if it were not so sad.
rodkeh
1.7 / 5 (6) Jan 14, 2019
More Fake science from phys.org!
This is such idiotic nonsense!
The laws of physics have NOT changed and, "f" is still equal to "ma"!
Bert_Halls
1.8 / 5 (5) Jan 14, 2019
Fuck trolls. If this board had any moderation (and not for lack of me attempting to incite it), you'd be back to beating your cousin-wives for entertainment instead of flogging yourselves on the internet.
Surveillance_Egg_Unit
1.8 / 5 (5) Jan 14, 2019
Fuck trolls. If this board had any moderation (and not for lack of me attempting to incite it), you'd be back to beating your cousin-wives for entertainment instead of flogging yourselves on the internet.
says BH

Then why do you continue to read and comment in physorg forums if you're so unhappy? Why not just read the article and try to get something out of it - then go your own way? There is no law that says that you have to read the comments - especially if they offend you. Do you enjoy being offended?
antigoracle
1.7 / 5 (11) Jan 14, 2019
Yet, the UNCOOKED ARGO data confirms that the oceans are COOLING.
NeMaTo
2.7 / 5 (7) Jan 15, 2019
don't feed the trolls people, ignore them
SamB
5 / 5 (6) Jan 15, 2019
This sounds like a good thing as wave power machines will have a 28% increase in output. Go green energy!
HeloMenelo
4.4 / 5 (7) Jan 16, 2019
Yet, the UNCOOKED ARGO data confirms that the oceans are COOLING.

Aaah did the monkey meeting have a head scrum to come up with make believe baboon results.
I wonder how long i took for him to come to this conclusion... Sorry boony, indisputable scientific data throughout the world in collaboration with many sources shows the oceans are WARMING ;)
HeloMenelo
5 / 5 (6) Jan 16, 2019
Yet, the UNCOOKED ARGO data confirms that the oceans are COOLING.

Too much fun, they talk so much drivel it's Hilarious one needs to have some fun :D
HeloMenelo
5 / 5 (6) Jan 16, 2019
More Fake science from phys.org!
This is such idiotic nonsense!
The laws of physics have NOT changed and, "f" is still equal to "ma"!

a a aaa...mommy told you to leave those gloomy shrooms alone...
gregie2017
Jan 16, 2019
This comment has been removed by a moderator.
snoosebaum
1 / 5 (1) Jan 16, 2019

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