ES_BIOMOD_1

BioScapes 1: Coupled Modeling of Climate, Dynamic Vegetation and Surface Processes From the Last Glacial Maximum to Present

01.01.2016 bis 31.12.2018

BioScapes I is part of a series of independent EARTHSHAPE proposals that quantifies biotic, surface process, and paleoclimate interactions at the catchment scale and larger. In this contribution, we propose for the first time a coupling between state-of-the-art paleoclimate, dynamic vegetation, and surface process numerical models using high-performance computing. These models will be applied to test three of the original EARTHSHAPE hypotheses, as well as four related key scientific questions identified here. Model results will be used to evaluate the sensitivity of surface processes and topography to different climate and vegetation forcing. Our new coupled modeling approach will quantify how the individual and combined contributions of continuous climate and vegetation change from the LGM to present have influenced the erosion, sedimentation, and morphology (relief, fluvial profiles, hillslope geometry, drainage density, etc) of the EARTHSHAPE study areas in the Coastal Cordillera, Chile. Model results will be compared to existing observations (topography, paleovegetation and paleoclimate proxies), as well as new observations (erosion and sedimentation rates, palynology, etc) collected as part of the EARTHSHAPE program. Our approach bridges a diverse range of timescales ranging from hours to tens-of-thousands of years, and provides a physics-based integration of diverse EARTHSHAPE products essential to the success of this priority program. In summary, the key items delivered from this study include: 1) downscaled quantification of climate and vegetation changes in Chile from the LMG (~21 ka) to present using an ensemble of climate models; 2) quantification of how erosion and sedimentation rates in the EARTHSHAPE focus areas have responded to the legacy of these temporal changes; and 3) identification of the individual roles and relative significance of climate vs vegetation change on catchment evolution along a latitudinal transect of catchments encompassing one of Earth’s largest ecological and climate gradients. These goals are achieved through the new pairing of investigators with extensive prior experience in the fields of biogeography (dynamic vegetation modeling) and geology/geophysics (paleoclimate and landscape evolution modeling).