Modeling Regional Paleovegetation of the Holocene in EasternUnited States: Upper Great Lakes

ATM-9709633 Sugita，明尼苏达新亚大学标题：模拟美国东部全新世的区域古植被上五大湖地区的气候和植被不仅受到大陆尺度的气团运动的影响，而且还受到底物和区域地形特征的影响，如苏必利尔湖、密歇根和休伦湖。在冰川晚期和全新世早期，大陆冰盖的消退和随后的均衡反弹极大地改变了五大湖和阿加西湖的大小和形状，这无疑影响了区域气候。草原-森林边界位置的变化可能会对区域气候产生进一步的反馈效应。该奖项支持对大湖上游地区全新世气候/植被相互作用的研究，以及编制区域气候模型(RegCM2)和植物/植被模型，以模拟目前以及11k、6k和3k校准的年份。花粉扩散/沉积模型将把植被模型预测的区域植被与湖泊中的花粉组合联系起来，可以与区域数据库中观察到的花粉化石进行比较。通过该模型/数据的比较，将评估耦合区域气候和植被模型的模拟的有效性。上五大湖地区高质量、年代准确的花粉记录的密度现在非常高，这使得能够进行比全球大多数其他地区更详细的空间模型/数据比较。

Abstract ATM-9709633 Sugita, Shinya University of Minnesota Title: Modeling Regional Paleovegetation of the Holocene in Eastern United States; Upper Great Lakes Climate and vegetation in the Upper Great Lakes region have been influenced not only by continental-scale movement of air masses but also by substrate and regional physiographical features such as Lakes Superior, Michigan and Huron. Retreat of the continental ice sheet and subsequent isostatic rebound dramatically altered sizes and shapes of the Great Lakes and Lake Agassiz during the late- glacial and early Holocene, which undoubtedly affected the regional climate. Shifts in the location of the prairie-forest border are likely to have had further feedback effects on the regional climate. This award supports an examination of Holocene climate/vegetation interactions in the Upper Great Lake region, and the preparation of regional models of climate (RegCM2) and flora/vegetation models as simulations of the present and of 11 k, 6 k and 3 k calibrated yrs. A pollen dispersal/deposition model, will link regional vegetation predicted by the vegetation models to pollen assemblages in lakes, which can be compared with observed fossil pollen from the regional database. Through this model/data comparison, the effectiveness of simulations which couple regional climate and vegetation models will be evaluated. The density of good-quality, well-dated pollen records in the Upper Great Lakes region is now extremely high, allowing a more spatially detailed model/data comparison than would be possible in most other regions of the globe.