In 1999, a widespread storm surge struck the Mackenzie Delta region of the Northwest Territories. Researchers from Queen’s and Carleton universities in Ontario studied the impact that the saltwater flooding had on the area’s ecology. They found that within a year of the surge, half of the alder bushes sampled were dead, while an additional 37 per cent had died within five years. Salt concentrations in the soil were still high a decade after the flood and sediment-core profiles from inland lakes revealed a striking shift from fresh- to saltwater species following the surge.

By studying growth rings from coastal shrubs and lake sediments, the researchers discovered that the region hasn’t experienced an event of such magnitude during the past
1,000 years.

‘One of the most ominous threats of global warming today is from rising sea levels, which can cause marine waters to inundate the land,’ said one of the team’s leaders, Joshua Thienpont of Queen’s University. ‘The threat is especially acute in polar regions, where shrinking sea ice increases the risk of storm surges.’

July 2011