Newspaper Article, February 2004

Think the groundhog is good?; Diablo's wave-rider buoy is vital for weather, wave forecasting

David Sneed, MORRO BAY

For most people living along the coast, ocean waves are an integral and beloved part of life. Surfers harness the ocean's power for sport. Others relish watching the spectacle of large waves crashing on the rocky shore. But for fishermen, divers and others who make their living off the ocean, waves are serious business. They must know when swells will arrive along the coast and how big they will be. That information is provided by a series of more than 25 compact, high-tech weather stations, called wave-rider buoys, that dot the Pacific Ocean from the Gulf of Alaska to Christmas Island in the central Pacific. One of these buoys sits a quarter of a mile offshore of the Diablo Canyon nuclear power plant. Another is deployed off Point San Luis near Avila Beach. No one knows the importance of these floating weather sentinels better than John Lindsey. As the marine meteorologist for the Diablo Canyon nuclear power plant, Lindsey uses the information the buoys generate to advise operators to reduce power at the plant when large waves are approaching. "The buoys are vital for weather forecasting," Lindsey said. "They give me actual data that is real, not just estimates."

The responsibility is a heavy and humbling one, Lindsey said. If he fails to detect heavy swells and they dislodge kelp that clogs the plant's cooling system, operators will have to do an emergency shutdown, which can damage equipment and lowers the plant's overall safety rating. If he predicts heavy surf and it does not arrive, operators will have reduced power needlessly, costing the company money and depriving electricity to the state's power grid. To prevent mistakes like that from happening, plant owner Pacific Gas and Electric Co. installed its own wave-rider buoy and established a sophisticated weather laboratory at the plant. Lindsey constantly monitors the data streaming in from the chain of wave-rider buoys. A specially designed computer program helps him pinpoint when heavy swells will arrive and how powerful they will be at the plant. He also produces a comprehensive daily weather report that he e-mails to more than 1,000 subscribers. Steve Pengilly, a professional diver and avid surfer, said he and others who work and play on the ocean rely on the accuracy of the report.

"He (Lindsey) usually can't get any work done because we're pestering him about the swell," Pengilly said. He recently helped Lindsey replace the Diablo Canyon wave-rider buoy. The plant has two of the buoys. One is kept as a backup and replaces the other when the batteries in the one in use run low. They are usually swapped out once a year. The Diablo Canyon wave-rider is typical of those all along the coast. It records the height of the swells, the direction they are coming from, the time between swells and the water temperature. It transmits this data to the plant's ocean lab. The data is relayed to the Scripps Institution of Oceanography in San Diego and the National Weather Service. But the Diablo Canyon buoy is different in one important way, said Rae Strange, a veteran wave scientist and consultant with Pacific Weather Analysis in Santa Barbara. While all of the other wave-rider buoys sit in deep water, the Diablo Canyon buoy is moored in water only 100 feet deep. The data from this shallow-water buoy helps scientist understand how waves behave as they approach the shore, Strange said.

Swells in the open ocean travel in predictable patterns, but not when they reach shore. Shoals reduce their power and promontories and other shoreline features refract them, making accurate surf prediction at different points along the coast difficult. "The Diablo Canyon buoy gives us site-specific data so we don't have to speculate what the effect of refraction and shoaling is," Strange said. "It gives us a good, accurate fix."

Such accuracy is a relatively new development. Historically, waves were mistakenly attributed to tides rather than wind. As early as the 1960s, big swells came as a surprise because there was no system for detecting and tracking them. Scripps deployed the first wave-rider buoys in the 1970s followed by the National Oceanographic and Atmospheric Administration in the 1980s, Strange said. Huge El Niņo-driven swells in 1983 destroyed the Unocal pier in Avila Beach. That event helped convince PG&E that it needed its own wave-rider buoy at Diablo Canyon, and the first one was installed June 15 of that year, Lindsey said. Amateur weather enthusiasts can now get real-time swell information from National Weather Service Web sites and look at raw data streaming in from individual wave-rider buoys. "Back in the old days, no one had any idea what was going on," Strange said. "Now, with the buoy system, everyone can find out what's going on, especially with the Internet."

San Luis Obispo Tribune
February 2, 2004