Incorporating a Meteorological Constraint to Plant Migration in a Dynamic Vegetation Model: Projections of Future Vegetation Distribution in the Pan-Arctic

In estimating natural vegetation composition, current Dynamic Global Vegetation Models (DGVMs) do not consider constraints (such as seed dispersal) to plant migration process; however, this lack of migration constraints could potentially lead to overestimation of vegetation carbon sequestration capacity (IPCC WG2). In this study, we have implemented a plant migration constraint driven by a meteorological condition (i.e., prevailing wind directions) that controls seed availability from neighbors, to the NCAR CLM-DGVM. In order to gauge the sensitivity of the Arctic natural vegetation response to different regional climate change patterns, we use two GCM patterns (dry & warm vs. wet & cool) imposed to the MIT-IGSM climate projections with three different climate sensitivities (i.e., high, median and low) over the period 2010-2100. Our result indicates that the unrestricted plant migration process in a current DGVM may have overestimated tree covers and underestimated herbaceous plant covers, compared to our seed-restricted DGVM. In addition, we analyze subsequent changes in albedo, plant biomass carbon, and surface runoff in the Pan-Arctic region.