LOGAN, Utah (AP) -- Researchers at Utah State University said they have found a predictable pattern to the wet-dry cycles of northern Utah.
The discovery of a rhythm could be useful in helping to manage crops, reservoirs and water use, said Rob Gillies, the director of the Utah Climate Center.
"It's giving you a telescope," Gillies said. "And allowing you to see into the future."
Gillies and his team studied suspected patterns against temperature measurements, precipitation readings, tree-ring data and Great Salt Lake levels. They looked at almost 1,000 years of data and found a relationship between sea-surface temperatures in a specific area of the Pacific Ocean and rainfall and snowfall in northern Utah.
The research suggests a 12-year cycle with a three-year delay. As the Pacific temperatures head toward their lowest, precipitation in northern Utah starts to increase. And a drought begins when ocean temperatures approach their warmest.
The team's findings have been published in Geophysical Research Letters and Journal of Climate.
The USU team also found two more precipitation cycles, one 40 years long, the other 150 years long.
Researchers found that the three cycles fell in line at the same time in the early 1980s, when northern Utah was hit with record precipitation, followed a few years later by higher-than-ever shoreline levels at the Great Salt Lake and flooding in downtown Salt Lake City.
Gillies' team also noticed that in the past 60 years or so northern Utah hasn't experienced the severe droughts that have been typical in the region.
The findings roughly follow a wet-dry pattern the Jordan Valley Water Conservancy District has seen over the years, said Richard Bay, general manager of the district, which serves more than 600,000 customers.
"It's not a total answer," Bay said. "But it would be a big help in predicting water supplies."
The finding of a link between sea-surface temperatures and precipitation cycles can also help guide future water use.
Utah is dealing with a fast-growing population and the prospect of drier periods that could come with climate change, said National Weather Service hydrologist Brian McInerney.
"If you can plan for what's coming, you can make it easier," McInerney said.