Computer models, weather satellites and ice cores are valuable tools for scientists who study how Earth's climate is changing. But a new study suggests that researchers can add another weapon to their arsenal: the knowledge gathered by indigenous people who have spent generations living off the land in rhythm with weather and seasons.

Researchers at the University of Colorado credit a combination of scientific data and traditional environmental knowledge from two Canadian Inuit communities for shedding new light on an overlooked aspect of climate change.

In recent years, Inuit communities that have long paid close attention to the climate have said their traditional forecasting methods are becoming less accurate. They blame the change on shifting weather patterns.

Scientists have attempted to confirm those claims for at least 15 years without success -- until now.

"This is not the first scientific paper on Inuit knowledge," said lead author Elizabeth Weatherhead, an atmospheric scientist at the University of Colorado. "But it is the first paper linking that Inuit knowledge to more scientific approaches."

The scientist said the detailed interviews with Inuit conducted by her co-author and University of Colorado colleague, Shari Gearheard, helped make the difference.

"Instead of just glossing over and taking a sort of sound bite -- 'The weather is faster' -- she really sat with people and found it was a problem and at what time scales," Weatherhead said.

Unexplained changes in weather persistence
The Inuit weather observers Gearheard interviewed told her that the strange weather behavior didn't occur every year or in every season, but it was becoming more severe when it did happen.

Meanwhile, Weatherhead combed through scientific data and discovered evidence supporting the Inuit observations.

"What we found is that the day-to-day persistence of weather was changing in this more unpredictable manner for at least one of the two locations" included in the study, she said, during a critical time of year -- Arctic spring, which occurs in June at the two Canadian sites.

In simple terms, what the researchers were looking at is how much weather changes from one day to the next, and how long a weather pattern -- like a heat wave or a cold snap -- lasts.

"We all grew up with the idea that if today is a warm day, tomorrow will be a warm day, too -- but we probably won't be stuck in a warm period for three weeks," Weatherhead said. "There's a natural time scale to weather events. That's what seems to be changing."

In most of the world -- including mid-latitudes, where much of the planet's population lives -- weather seems to be getting more persistent.

But at the Baker Lake site in the Canadian Arctic province of Nunavut, weather events seem to be getting less persistent -- shorter. Scientists didn't observe such a change at the second place they studied, the community of Clyde River, also located in Nunavut.

Though they don't fully understand what caused the different outcomes at the two sites, Weatherhead speculated it had something to do with Clyde River's proximity to Baffin Bay, and the influence of weather patterns that develop over the oceans.

Inland areas, like Baker Lake, are more sensitive to changes in land use and snow cover, she said.

Overlooked and underappreciated by mainstream scientists
The new study is not the first attempt by scientists to draw on indigenous environmental knowledge. Projects funded during the 2007-2008 International Polar Year, for example, documented different Arctic native populations' rich vocabulary for different types of sea ice and plumbed the communities' observation of changing caribou behavior.

But Mead Treadwell, chairman of the U.S. Arctic Research Commission, said the new work is another piece of evidence that justifies the attention to indigenous knowledge that has been overlooked and sometimes dismissed by mainstream science.

That's one reason his commission has urged measures ranging from preserving indigenous languages of the Arctic to encouraging scientists and native peoples to collaborate on scientific research.

"If you lose the language that people have been speaking for 10,000 years as it has evolved, you lose a huge amount of information that is built up in the language," he said. "If something is named 'a place where the caribou mate,' that tells you the caribou were once there if they are not there now. If you lose a particular plant that might translate as 'medicine weed,' you understand how it has been used."

Treadwell noted that, in two separate instances, the U.S. National Oceanic and Atmospheric Administration changed its estimate of the Arctic's bowhead whale population based on native reports that showed more whales than the government initially counted.

For her part, Weatherhead said her next step will be examining how climate change affects the persistence of weather patterns around the world.

"This increase in persistence that we're seeing in very many places is just as important as the decrease in persistence that Arctic inhabitants are talking about," she said. "It has potential human health impacts, for example. People with asthma can often take one day of bad weather. Two is stressful. But at three, they might find themselves in the emergency room."

The study will be published this month in the journal Global Environmental Change.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500