| The management of Canada's fresh water resource has important implications for communities, agriculture and industry. However, instrumental records impose limitations on our understanding of historical variability of this resource due to the relatively short period of record. Proxy data sources can provide valuable information by extending the historical record.; Tree ring chronologies were developed in the Churchill River Basin to analyze the potential for stream discharge reconstructions. Samples were collected from moisture sensitive trees, and used to construct thirteen ring-width chronologies.; Significant relationships were identified between the index chronologies and stream discharge data. These relationships were used to reconstruct stream discharge as far back as 1840, considerably longer than the instrumental record, which begins in 1930. The level of uncertainty associated with each reconstruction was assessed. In addition, results were compared to those from independent research and to historical documentation; there was generally good agreement between the results.; Extensive periods of below average discharge were identified in the mid and late 19th century, as well as early in the 20th century. An unprecedented period of above and below average discharge in the last half of the 20th century was also identified. Tree-ring reconstructions provided the longer context within which to assess stream discharge variability captured by the instrumental record. |
