Identifying Global‐Scale Patterns of Vegetation Change During the Last Deglaciation From Paleoclimate Networks

During the last deglaciation (∼19–11 ka before present), global mean temperature increased by 3–8 K. The concurrent hydroclimate and land cover changes are not well constrained. Here, we use a pollen database to quantify global-scale vegetation during this transitional period at orbital (∼104 years) millennial timescales (∼103 years). We focus on proportion of tree shrub pollen, arboreal (AP) fraction. Temporal similarities over long distances identified paleoclimate network approach. At scale, find coherent AP variations in low mid-latitudes which attribute climate forcing. While fractions predominantly through deglaciation, identify regions where decreased. For timescales, do observe spatially similarity structures. compare our results with networks computed from three deglacial simulations CCSM3, HadCM3, LOVECLIM models. Networks based simulated precipitation patterns reproduce characteristics network. Sensitivity experiments statistical emulators indicate that, indeed, explain diagnosed change better than CO2 variations. Our findings support previous interpretations forest evolution being result atmospheric circulation changes. analysis identifies differences vegetation-climate-CO2 relationship CCSM3 HadCM3. conclude that analyses promising tool benchmark transient dynamical This may stronger constraints future