Tree rings provide a window into Quebec’s 19th century climate for researchers

Quebec tree rings dating back nearly 200 years indicate snowpack in the Gaspésie mountains has declined considerably in recent decades, Concordia University researchers suggest.

Quebec tree rings dating back nearly 200 years indicate snowpack in the Gaspésie mountains has declined considerably in recent decades, Concordia University researchers suggest in a study that could give further insight into dwindling caribou herds and hydro energy forecasts.

The tree ring study goes back to 1822, extending by more than 100 years the records otherwise kept by local weather stations and river gauges. It underlines how climate change has already reshaped the region, the study said.

“This reconstruction may prove useful for wildlife, fisheries and hydroelectric reservoir management,” said the study, published in Journal of Hydrology: Regional Studies.

By studying the tree rings in the Sainte-Anne River basin, the researchers say they observed a climate-change linked decline in extreme spring river flows and snowpack levels since 1937.

“The system was at a tipping point, and it didn’t take much global warming to push it to where we’ve lost the extreme snowpacks the mountains used to have,” said Jeannine-Marie St-Jacques, the study’s co-author and an associate professor at Concordia University in Montreal.

The results, the study said, offer more long-term context for the “highly endangered” caribou population on the Gaspé Peninsula, the last herd south of the St. Lawrence River. The population has collapsed since the 1950s from estimates as high as 1,500 to 34, according to government figures.

Habitat degradation from logging is considered the caribou’s most pressing threat but declining snowpack adds to their problems, researchers say. Caribou breed in the alpine and deep snowpack can offer protection from predators.

“When there’s less snow, there’s easier access for predators to get up there early in the spring when the fawns are more vulnerable,” said Alexandre Pace, the study’s lead author and a PhD candidate at Concordia.