Abstract ATM-9709117 Barron, Eric Pennsylvania State University Title: Evaluation of the Role of Climate-Vegetation Interaction During Earth History Vegetation distribution an d character are largely viewed as a function of climate in most paleoclimate studies. For this reason, vegetation has been specified as "globally uniform" in the majority of paleoclimate model experiments. However, previous studies indicate that inclusion of a dynamic surface vegetation is a critical factor in climate model experiments. This award supports a project to utilize the wealth of exiting information and models on biosphere-atmosphere interaction, modified explicitly to maximize their application to earth system history, in order to improve climate model simulations of past climates and to assess climate sensitivity. The major components of the study: (1) evaluation of the climatic significance of vegetation character and distribution, (2) evaluation and then selection of a vegetation model, appropriate for paleoclimate study, for coupling to a General Circulation Model (GCM), (3) development of a dynamic interaction scheme for the climate-vegetation model, (4) evaluation of the coupled model for modern climates, and (5) assessment of model results for a variety of past climates. This project focusses on the assessment of three different types of vegetation models, and will apply them to the Last Glacial Maximum, the Miocene, the Eocene and the mid-Cretaceous. This project will enhance our ability to apply climate models to the study the earth history, explicitly examine the importance of the terrestrial system as a factor influencing climate, and contribute to our knowledge of both past and future climate change.
