Every three decades or so, over the last thousand years, the climate of Alberta has flipped from dry periods to wet and back again.
Trees a millennium old in the front ranges of the Rocky Mountains have grown correspondingly faster or slower in relation to precipitation trends.
It is a correlation that Dave Sauchyn has researched, studying the varying widths of tree rings from centuries-old trees in Southern Alberta to determine tree growth in wetness and in drought.
From the rings, he is able to put together statistical models going back hundreds of years on precipitation, showing 30-year alternating patterns.
“We would like to say, we’ve got this 1,000 years of tree rings and there’s this consistent 60-year cycle over 1,000 years, so get used to it. But we can’t do that.
“We can’t predict anything because the world is changing. The temperature is shooting up all over the world,” said Sauchyn, speaking on Thursday at the Visions 2013 conference put on by the Alberta Agricultural Economics Association.
The temperature cycles are based on Pacific Decadal Oscillation (PDO), a pattern of change in the Pacific Ocean’s climate. However, with a warming climate increasing ocean temperatures, the predictor has been thrown for a loop.
“Until about 30 years ago, there was a fairly good, strong link in the weather and the tree growth, and then that link began to change. We think because the climate has changed so quickly that the trees aren’t behaving like they used to,” explained Sauchyn, a researcher at the Prairie Adaptation Research Collaborative at the University of Regina.
“The tree rings have told us a lot about the climate of Alberta over the last 1,000 years and, even more, that that climate no longer exists.”
The cycle flipped to a period of wetness in 2008, according to Sauchyn.
Thus, Alberta can likely expect fairly good moisture over the next 30 years, followed by a period that could be “brutally dry,” although, he added, there are always exceptions from year to year.
He said people and governments would be wise to take note of the decadal patterns, saying to laughs that Sylvan Lake should not consider dredging up a beach to replace sand lost to historically high water levels, but rather “just wait 30 years!”
“During one 30-year cycle you get a lot of drought, in the next 30-year cycle you get virtually none. If you know that, you can adjust your practices, whether you’re a municipality, a provincial government or a farmer or rancher,” said Sauchyn.
Sauchyn’s research on tree growth and climate is continuing, with ongoing weather monitoring and tree growth sampling in Alberta.
l Canadians do not know much about sustainable labelling, but significant numbers are willing to pay a premium for products labelled as such, according to research from the University of Manitoba.
Research done at the Winnipeg university was presented Thursday at the Visions 2013 conference in Red Deer put on by the Alberta Agricultural Economics Association.
The research, based on a survey of 1,500 Canadians this January, found that, while Canadians may make a habit of buying sustainability-labelled products, they may not be doing so knowingly.
The study found that Canadians do not have a high recognition of labels, such as those signifying ‘fair trade certified’ or ‘animal welfare approved.’
It also found that female consumers have a higher willingness to pay for sustainability-labelled goods, while older consumers and those who say price is important to them have a lower willingness to pay premiums.
Another study found that Canadians had a willingness to pay 12 to 18 per cent premiums for ground beef that had been enhanced with omega-3.
The Visions conference, which continues today at iHotel on 67th Street, has been taking place in Red Deer for the last 30 years.
This year’s conference brought together 70 people from Alberta, Saskatchewan and Manitoba representing academic, agricultural and governmental organizations.
mfish@www.reddeeradvocate.com