Researchers study hazards of rising seas, wave heights

Newport News Times (Oregon): While hurricanes Gustav and Ike were pummeling the Gulf Coast with rains and record flooding, researchers at Oregon State University were studying why wave heights in the Pacific Ocean have been increasing in recent years and how this phenomenon - coupled with global climate change - might affect coastal erosion, flooding and development along the Pacific Northwest coast.

Peter Ruggiero, an assistant professor of geosciences at OSU, is developing new computer models that factor in the increasing wave heights, as well as rising sea levels and the potential increase in frequency of El Niño weather conditions. El Nino is a cyclic water temperature weather pattern that results in warmer-than-normal ocean temperatures and triggers larger storms in the Pacific Ocean.

“We're trying to see how a combination of these different processes - bigger waves, higher sea levels and potentially more frequent and intense El Niño conditions - could affect coastal areas along the Pacific Coast in a range of ways, from coastal erosion and lowland flooding to planned development,” said Ruggiero, whose research is funded in part by a $190,000 grant from Oregon Sea Grant at OSU.

…“If you're thinking only about sea level rise, you're missing the boat,” Ruggiero said. “When we combine all these processes, the probability of waves overtopping a dune or banging into a sea cliff is three to 10 times greater than models that use only sea level rise projections.”

…Ruggiero's colleagues - Paul Komar, an emeritus professor in the OSU College of Oceanic and Atmospheric Sciences, and Jonathan Allan, of the Oregon Department of Geology and Mineral Industries - have been documenting observed wave heights in the Pacific Ocean for the last 30 years. Their research shows that the average wave height has increased more than 40 centimeters (15.7 inches) during that time, and the average wave height of the five largest winter storms per year is increasing at a rate of up to seven centimeters (2.75 inches) per year.

A wave at Asilomar State Beach in California, shot by Tewy, Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2