A GCM-based analysis of circulation controls on delta O-18 in the southwest Yukon, Canada: Implications for climate reconstructions in the region

作者：Field Robert D^*; Moore G W K; Holdsworth Gerald; Schmidt Gavin A

来源：Geophysical Research Letters, 2010, 37: L05706.

DOI：10.1029/2009GL041408

To improve our understanding of paleoclimatic records in the southwest Yukon, we examined controls on precipitation delta O-18 using an isotopically-equipped atmospheric general circulation model (GCM). Our results show that, particularly during the cool-season, elevated delta O-18 is associated with a deeper Aleutian Low and stronger southerly moisture flow, while lower delta O-18 is associated with the opposite meteorological conditions. These results suggest that the large mid-19th century shift towards lower delta O-18 values seen in paleoclimate records from the region was associated with a shift towards a weaker Aleutian Low. While in disagreement with a previous interpretation of this shift, it is consistent with records of glacial advance and tree-ring growth during the same period, and observational studies of Aleutian Low controls on temperature and precipitation in the region. Citation: Field, R. D., G. W. K. Moore, G. Holdsworth, and G. A. Schmidt (2010), A GCM-based analysis of circulation controls on delta O-18 in the southwest Yukon, Canada: Implications for climate reconstructions in the region, Geophys. Res. Lett., 37, L05706, doi:10.1029/2009GL041408.

• 出版日期2010-3-9