A research partnership between the University of Northern British Columbia and Princeton University is confirming the projections of early climate models. The study, led by UNBC Environmental Science and Engineering professor Stephen Déry, verifies that global warming is causing significant variations in the volume of water flowing along Canada’s northern waterways.

The research, to be published next month in an international Geophysics journal confirms early predictions of how an increase in global temperature will affect arctic and sub-arctic regions. The study indicates that global warming is causing hydrological cycles to intensify, thus inducing weather systems to “teeter-totter”. This is reflected in dramatic increases in precipitation in some areas and decreases in others, and is having a profound effect on river water volume.

“If rivers are the veins of Canada, we’re having some pretty dramatic blood pressure fluctuations,” says Dr. Déry. “This affects a variety of things: farms, forest fires, fish-dependent First Nations communities, and many others. An increase in fresh water discharge into the Arctic Ocean also impacts climate on a global level.”

Changes in river water volume can lead to drops in fish stocks, drought, flooding, and a litany of interconnected problems, which have an impact on the health of people, ecosystems, and northern industry.

As part of their research, Dr. Déry and his collaborators collected data from weather stations across the North to find out exactly how precipitation is changing. The results confirm early predications that higher elevations and latitudes will experience more climate change, and lead to powerful fluctuations in the intensity of weather systems.

For example, Dr. Déry’s research shows that the Yukon River’s annual fluctuation increased by approximately 20%. From 1964 through 1986, the standard deviation was 8.15 cubic kilometres per year. From 1988 until 2008, this had increased to 10.51 cubic kilometres per year.

“One of the more counter-intuitive elements of global warming is that, when temperatures increase, it can lead to both drought and flooding,” says Dr. Déry. “In some cases, a temperature increase leads to more moisture in the air, which causes heavy precipitation and flooding, while in other areas, it can lead to an increase in evaporation, which produces drought. As both of these are extremes that we would rather avoid, this information is significant.”

The study is part of the International Polar Year project, a large scientific program focused on the Arctic and the Antarctic. In Canada, the project concentrated on the Arctic drainage basin, which drains more than half of the country’s land surface.