Climate change, mean sea level and high tides in the bay of fundy

Abstract

Global warming is predicted to result in a rise in sea level which will lead to increased flood risk. Two other factors that will affect high water are the existing trends in mean sea level and changing tides. We illustrate here that in the Bay of Fundy and Gulf of Maine these two are related. An analysis of long-term sea level records shows that, independent of global warming related to climate change, sea level and tidal range have been increasing in this system. Our numerical model investigation indicates that recent changes in sea level, attributed in part to post-glacial rebound, are giving rise to increasing tides. The combined effects of modern sea level rise, global warming induced sea level rise, and the expanded tidal range they induce, will produce a significant increase in the high water level, much greater than that found when considering modern climate-induced sea level changes in isolation. We are predicting a dramatic increase in the risk of flooding at higher high water during the twenty-first century.