By JULIE WATSON (Associated Press)
A new study reveals that waves off the coast of California are growing larger, with surf reaching heights of at least 13 feet (about 4 meters). This research, conducted by oceanographer Peter Bromirski at Scripps Institution of Oceanography, utilized an innovative method of analyzing seismic records dating back to 1931 to measure the increase in wave height over the past 90 years.
The analysis involved tracking the impact of waves colliding with incoming waves and causing energy ripples through the seafloor, which were recorded by seismographs originally designed to detect earthquakes. The higher the impact, the taller the wave.
Prior to this study, scientists relied on data collected by the National Oceanic and Atmospheric Administration from a network of buoys along the U.S. coasts. However, this data only covered the California coast starting from 1980.
“Until I stumbled upon this data set, it was almost impossible to make that comparison with any kind of reliability,” said Bromirski.
To go back further in time, Bromirski enlisted a team of undergraduate students to analyze decades of winter seismic readings by digitizing paper records. This meticulous process took years but provided valuable insights into how wave patterns have changed over almost a century along California’s coast.
Their findings revealed that average winter wave heights have increased by approximately a foot since 1970, when it is believed that global warming began accelerating. The frequency of swells at least 13 feet tall has also doubled between 1996 and 2016 compared to the period from 1949 to 1969.
Bromirski was also surprised to discover extended periods of exceptionally low wave heights before 1970, which have not occurred since.
“The occurrence of erosion, coastal flooding, and damage to coastal infrastructure has become more frequent than in the past,” Bromirski explained. “Combined with sea level rise, bigger waves will only exacerbate these issues.”
Changes in wave patterns are not limited to size alone. Bromirski noted, “There’s about twice as many big wave events since 1970 as there was prior to 1970.”
This study, published in the Journal of Geophysical Research: Oceans, adds to the mounting evidence that climate change is causing significant shifts in the world’s oceans. Other studies have indicated that waves are not only getting taller but also more powerful.
These changes have already led to damage from intense storms and massive surf along the California coast. Recent severe storms and giant waves have caused bluff collapses, pier damage, and flooding along Highway 1.
Bromirski warns that this is just the beginning. As global warming continues and sea levels rise, bigger waves will result in increased flooding, beach erosion, landslides, and the destabilization of coastal cliffs.
Particularly in California, where sea cliffs have already crumbled and demolished homes in recent years, these issues are of great concern. The study suggests that even moderate waves towards the end of the 21st century could cause damage comparable to extreme weather events.
Oceanographer Gary Griggs, from the University of California Santa Cruz, agrees with the findings of the study and emphasizes the urgency of addressing these changes. He notes that while a one-foot increase in wave height over 50 years may not seem significant, it aligns with the growing evidence of the world’s warming and rising seas.
“We know hurricanes are more intense and last longer, and now we’ve got waves increasing in power. So those are all consistent,” said Griggs. “The challenge lies in how to effectively respond to these changes.”
Denial of responsibility! VigourTimes is an automatic aggregator of Global media. In each content, the hyperlink to the primary source is specified. All trademarks belong to their rightful owners, and all materials to their authors. For any complaint, please reach us at – [email protected]. We will take necessary action within 24 hours.
