GRGC: Reconstruction of Water Balance Fluctuations During the Last Deglaciation Based on Glacial/Lacustrine Systems in the Western Great Basin

最后一次冰期的结束是由一系列重大的和突然的气候事件完成的。显然，大气中水汽输送的变化在冰川消融过程中起了关键作用。虽然这些事件显然导致了全球冰川条件的分离，但北大西洋地区以外的地区对事件顺序的细节知之甚少。在这个项目中，我们建议应用新的年代学和古水文方法来解释单一封闭流域的冰川和湖泊数据：大盆地西部的古欧文斯河系统。我们将应用质谱U/Th和宇宙成因36Cl定年来完善终端盆地湖泊沉积物和海岸线的现有年代学。该年表将与欧文斯河源头内华达山脉东部冰川沉积物和地表的36Cl和碳14年表进行比较。这些新的和完善的年表将使冰川和湖泊系统的事件序列能够相互比较。然后将使用瞬态数值能量和质量平衡模式，根据气候驱动力对组合序列进行定量解释。最后，可以将重建的气候历史与最近的全球冰芯和海洋沉积物记录进行比较，以评估全球事件如何通过大陆环境下温度和水汽输送的变化来反映。

9417810 Phillips The end of the last glaciation was accomplished by a series of major and abrupt climatic events. It is clear that changes in the atmospheric transport of water vapor played a key role in the deglacial process. Although these events apparently resulted in a global secession of glacial conditions, the details of the sequence of events is poorly known outside the North Atlantic region. In this project we propose to apply new geochronological and paleohydrological methods to the interpretation of glacial and lacustrine data in a single, closed drainage basin: the paleo-Owens River system in the western Great Basin. We will apply mass spectrometric U/Th and cosmosgenic 36Cl dating to refining the existing chronology for lacustrine deposits and shorelines in the terminal basins. This chronology will be compared with one derived from cosmosgenic 36Cl and carbon-14 for glacial deposits and surfaces in the eastern Sierra Nevada, at the headwaters of the Owens River. These new and refined chronologies will allow the sequence of events for the glacial and lacustrine systems to be compared with each other. The combined sequence will then be quantitatively interpreted in terms of climatic driving forces, using a transient numerical energy and mass balance model. Finally, the reconstructed climatic history can be compared with recent ice core and marine sediment records of global conditions to assess how the global events were reflected by changes in temperature and water vapor transport in a continental setting.