On the north coast of North America, the biggest river is the Mackenzie, carrying some 300 cubic kilometers of freshwater from Canada’s Northwest Territories to the Arctic Ocean every year. Ocean currents eventually bring a fraction of this freshwater between Canada and Greenland through Davis Strait and into the North Atlantic.
Freshwater entering the North Atlantic through the Davis Strait has the potential to disrupt deep convection and thereby inhibit global thermohaline circulation, an important process by which ocean currents redistribute heat and help moderate the climate. Furthermore, the collection of this river runoff into coastal currents will also lower the saturation state of calcium carbonate and exacerbate ocean acidification in this already vulnerable area of the world.
The Mackenzie isn’t the only river draining into the Arctic and delivering nutrients to the North Atlantic, however. Numerous smaller rivers flow across the North American mainland and the Canadian Arctic Archipelago (CAA), the islands north of Canada and west of Greenland.
To assess the importance of these small rivers to freshwater export from the Arctic region, we’ve started a project called Assessing the Impact of Small, Canadian Arctic River Flows (SCARFs) to the Freshwater Budget of the Canadian Archipelago. This new research project compares the chemical signatures of small rivers spread across the CAA with those of larger North American rivers such as the Mackenzie and Yukon. It also seeks to ascertain whether CAA rivers significantly contribute to the total volume of freshwater draining through Davis Strait.
Alkire M., Jacobson A. D., Lehn G. O., and MacDonald R. (2015): Small rivers could have big impact on Arctic Ocean. Eos, Transactions American Geophysical Union 96. DOI: 10.1029/2015EO034005