Katherine Klink, Associate Fellow

Modeling Regional Climate-Vegetation Interactions During the Holocene
in the Upper Great Lakes Region

  Climate and vegetation in the Upper Great Lakes region (Minnesota, Wisconsin, and Michigan) have been influenced not only by continental-scale movement of air masses but also by substrate types and regional features such as the Great Lakes and the prairie-forest border. For a better understanding of Holocene climate-vegetation interactions in the Upper Great Lakes region, regional models of climate (RegCM2) and flora/vegetation (STASH and FORSKA) were used to evaluate land surface-atmosphere interactions for the present day and for 11,000 (11k), 6k, and 3k years ago. Output from these models was linked to a pollen dispersion model (POLLSCAPE), and the results compared to observed fossil pollen from a high quality, well dated regional pollen database. The similarity of predicted and observed pollen assemblages were used to evaluate climate predictions. When disagreements occurred, their patterns in space and time helped to identify sources of error, and sensitivity studies continued to be used to evaluate the modeling strategies.