The Port Community
Oceans are Making Waves: The number and intensity of
“extratropical” storms are increasing

By Don McManman

Researchers examining the Atlantic and Pacific are predicting significant increases in the number and intensity of storms, and wave height.

The most recent study was published by two scientists from Oregon State University and a researcher from the Oregon Department of
Geology, based on weather buoy records off the Northwest coast.

In a nutshell: “The average wave goes up a centimeter and a half per year. If you just look at winter waves, they’re getting bigger by 2.5 centimeters a year. The largest waves, they’re going up 10 centimeters a year. That’s roughly 30 feet in 30 years,” said Peter Ruggiero, lead author and assistant professor in Oregon State University’s Department of Geosciences.

It’s the same trend noticed in the North Atlantic by scientists at the Dutch Koninklijk Nederlands Meteorologisch lnstituut in 1996. They examined records from the Sevenstones Lightship off the Isles of Scilly, west of Cornwall, from 1960 through 1985.

The Dutch were unhestitant in their results: Waves are getting bigger in the North Atlantic.

More recently, the Oregon scientists focused on the Northwest/British Columbia coast. Waves are getting bigger there too, and there’s every indication the trend will continue.

The scientists said the number and intensity of “extratropical” storms are increasing. Such storms are spawned in the middle latitudes, unlike tropical hurricanes or polar blasts.

Why the increase?

The scientists speculate it’s a function of global climate change.

The Oregon scientists focused on ocean waves, measured by anchored weather buoys more than 200 miles off the Columbia River bar.

Ruggiero’s numbers speak to increases, not the total wave height.

But even those figures are deceptive. They’re averages. In the future, there will be some stunningly big waves added to the mix of
bigger waves.

“There are waves much larger than average. They could be one and a half or two times bigger,” Ruggiero said.

But that doesn’t include rogues, abnormally huge waves formed in a fashion not completely understood by scientists.

“Rogue waves are more complicated. It’s a random process. Two waves may merge, but instead of canceling each other out, they are added together,” Ruggiero said.

If your wave brood stock is larger, the occasional rogue will be even bigger than one of a few years ago.

Ruggiero was joined by Paul D. Komar, an oceanographer at OSU, and Jonathan Allan of the Oregon Department of Geology in the wave analysis. Their report was published a few weeks ago in a journal called Coastal Engineering.

The scientists focused on Buoy 46005, a much-battered scientific instrument anchored 250 miles off the mouth of the Columbia. They also snatched some information from Buoy 46002, anchored 280 miles off Coos Bay.

The authors looked at weather buoy data from 1976, when the buoy was deployed, through 2007. There were periods when 46005 was out of commission, but information before and after the outage showed the same trend: Ever increasing wave heights.

The scientists were able to extend their storm graph backward – “hindcasting,” as opposed to forecasting – and it matched land-based reports dating back to the late 1940s.

The buoys measure deep ocean conditions beyond the continental shelf. How waves mature as they approach the coast varies with currents, wind, and ocean-bottom characteristics.

The study covered three decades, which included at least one major El Nino event. But by the nature of such phenomena, any El Nino will make big waves get even bigger, Ruggiero said.

The scientists also note that most of the study period covered what they call the “decadal shift,” a grand change in ocean
temperature conditions.

The major regime shift began in the ‘70s, when Buoy 46005 was positioned. Some experts say that shift ended in the 1990s. Since then, waves have grown even larger.

In This Issue

Up Front

News, Trends & Analysis
News

Trade Tools: Missing money

Capitol Watch: Focus on job creation

Supply Chain
Chris Steele: Why you might be buying industrial real estate soon

Compliance Corner: Use the Web for denied party lists

Tech Trends: From open source to terminal visibility

Product Review: Trucking drayage and chassis management software

Commentary
David Bennett: Real signs of trouble

Gateway Glance
New England

Southern California

The Port Community
Bumpy Ride: Rebuilding PNW containerized exports

Southwest Intermodal: Can intermodal incentives show the way?

The Shipping Environment: Engaging in the community,
slow steaming, and new green products

Oceans are making waves

Casualties
The Big Texas spill leads off this month’s rundown

Final Say
Top 25 TIGER projects