Reconstructing climate and hydrological variability in the Canadian cordillera

目前和未来气候变化对加拿大科迪勒拉和邻近草原的最关键影响将与灌溉用水、水力发电、人类消费等在需求增加时的可用性有关。该项目研究了加拿大科迪勒拉选定地区水文循环组成部分的时空变异性，通过开发过去水文气候和积雪变异性的树木年轮重建，检查仪器流量记录的变化以及最近冰川覆盖变化的文件。最近来自美国的研究表明，在过去的50年里，冬季积雪显著减少，水流时间提前，以及水流季节性分布的变化，可能严重影响夏季水流。正在进行的研究表明，冬季积雪量、冰川质量平衡和夏季流量的这些强连贯的区域变化模式是由PDO、ENSO和全球温度的变化驱动的。该项目的一个关键要素将是确定那些树木年轮序列对冬季降水或积雪敏感的树种，以便对夏季水流进行水文上的实际重建。它还将对过去几十年来选定冰川最近（在某些情况下是每年）的衰退作出估计。这些研究将为IAI资助的一个新的国际跨学科合作研究网络作出贡献，该网络将检查北美、墨西哥、玻利维亚、智利和阿根廷科迪勒山脉的水文气候变化。

The most critical impacts of ongoing and future climate changes in the Canadian Cordillera and adjacent prairies will be related to the availability of water for irrigation, hydro power, human consumption, etc. in times of increased demand. This project examines the spatial and temporal variability of components of the hydrological cycle in selected regions of the Canadian Cordillera by developing tree-ring reconstructions of past hydroclimate and snowpack variability, examination of changes in the instrumental streamflow record and documentation of recent changes in glacier cover. Recent studies from the US have shown marked reductions in winter snowpack, earlier streamflow timing and changes in the seasonal distribution of flows during the last 50 years that could critically affect summer flows. Ongoing studies show these strong coherent regional patterns of variation in winter snowpack, glacier mass balance and summer streamflow are driven by variations in the PDO, ENSO and global temperatures. A critical element of the project will be to identify those tree species with tree-ring series sensitive to winter precipitation or snowpack in order to develop hydrologically realistic reconstructions of summer streamflows. It will also develop estimates of recent (in some cases annual) recession of selected glaciers for the past few decades. These studies will contribute to a new international, interdisciplinary Collaborative Research Network funded by IAI that examines hydroclimatic variability in the cordillera of North America, Mexico, Bolivia, Chile and Argentina.