Mackenzie Delta river-ice breakup

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Freshwater ice is an integral component of northern rivers and an important modifier of related biological, chemical and physical processes.   Although many concerns have been expressed about the potential impacts of climate change on ice-covered systems, our knowledge base remains relatively weak thereby making it difficult to predict the nature and magnitude of the effects of a changing climate on ice-covered systems.   Moreover, even basic information on river-ice systems in northern Canada has been a problem for proper assessment of the potential environmental impact of development, including  oil and gas development along the Mackenzie River and most recently directly within the Mackenzie River Delta.  Although river-ice breakup is known to create the dominant hydrologic event of the year in the Delta and is essential to its ecological health, there is a lack of information about how variations in climate have controlled the timing, severity and intra-delta spatial dimensions of such events.  Moreover, little is know what effects future climate will produce.This project focuses on filling some of our most important knowledge gaps with the following objectives:i. quantify the detailed spatial and temporal variations in river ice breakup within the Mackenzie River Delta;ii. establish the significance of breakup events, as measured by magnitude and recurrence interval, to annual flow events produced under open-water conditions within the delta;iii. quantify the relationship between temporal changes in river-ice breakup timing and severity with major controlling hydrologic and climatic conditions that affect the forces driving breakup (e.g., flood wave) and factors resisting breakup (e.g., ice thickness and mechanical strength), andiv. relate the major controlling hydro-climatic conditions to atmospheric circulation patterns.The related long-term objective of the proposed research is to predict how the timing and magnitude of extreme breakup events will be affected by climate-change induced modifications of major temperature and precipitation patterns.