New Advances in Cold Region Hydrology

多年冻土环境被认为对变暖敏感，最明显的是在南部边缘，那里的冻土通常处于或略低于冰点，容易融化。此外，与其他季节相比，冬季变暖的速度最快。目前，有相当大的不确定性，永久冻土流域将如何应对变化，因为有矛盾的科学证据在更大的规模。这个研究项目将提高我们的理解高山冻土系统如何水文响应气候变化，提高我们的理解存储和径流，沿着通常被忽视的越冬过程。两个项目将提高我们对融化的永久冻土和当前条件如何影响水在流域中停留的时间以及永久冻土如何影响水流路径的基本理解。这将通过研究沿着育空地区纬度梯度的三个流域，结合能够模拟未来气候变化影响的新的数值模型来实现。该项目的第二阶段将侧重于两项实验，利用新的传感器：多功能热脉冲探测器和宇宙射线探测器，研究土壤中的冬季水分运动和渠道结冰的形成。冬季研究的结果将揭示这些过程对北方系统整体水文的重要性，并为它们在气候变化下的潜在反应提供指导。

Permafrost environments are considered sensitive to warming, most notably at the southern margins where frozen ground is often at or just below the freezing point and susceptible to thaw. Furthermore, warming is occurring most rapidly in winter compared with other seasons. At present, there is considerable uncertainty as to how permafrost watersheds will respond to change as there is conflicting scientific evidence at larger scales. This research project will improve our understanding of how alpine permafrost systems respond hydrologically to climate change by improving our understanding of storage and runoff, along with over-winter processes that are typically neglected. Two projects will improve our fundamental understanding of how thawing permafrost and current conditions influence the time water stays in the watershed and how permafrost influences flow pathways. This will be achieved by examining three watersheds along a latitudinal gradient in Yukon combined with novel numerical models capable of simulating the impact of future climate change. A second phase of the project will focus on two experiments examining over-winter water movement in soils and the formation of channel icing (aufeis) using new sensors: multi-function heat pulse probes and cosmic ray probes. Results from winter research will reveal the importance of these processes on the overall hydrology of northern systems and provide guidance as to their potential response under a changing climate.