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• Main Author: C Ca
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Bowser; Canada; Spence; Subarctic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.587.4704; http://www.science.uwaterloo.ca/~jjgibson/mypdfs/bakercreek.pdf

lding yge the subarctic Precambrian Shield region. As measured in water samples collected over a 12 year period (1997–2008), the levels of evaporative isotopic enrichment in both lake and watershed outflow were dif-mon f or intermittent runoff. This variability is driven by fluctuations in storage, and expansion and contraction of contributing areas as lakes, low-lying wetlands and soil filled valleys respond to snow-melt, rainfall and evaporative demand. This ‘fill-and-spill ’ mecha-nism (Spence and Woo, 2003), while also relevant to humid as a special case of heavy isotope enrichment in a coupled evapo-rative system (see Gat and Bowser, 1991), which has shown that cumulative heavy isotope enrichment signals down a string-of-lakes can be quantitatively interpreted particularly when humidity exceeds 50%. Broad areal surveys of lakes have shown that imprint of evaporation is widespread across boreal, subarctic and low arc-tic regions of Canada (Gibson et al., 2005). The purpose of this pa-per is to examine and interpret the controls on temporal isotopic signals associated with evaporation loss in lake and watershed dis-charge, and to demonstrate and critically evaluate a transferable