Climate Forcing Across Multiple Scales and Landscape Types within the Arctic Tundra Ecosystem

Pan-Arctic spatial heterogeneity is a major challenge to predicting the impact that present and future Arctic landscape features will have on the global climate system. Drained thaw lake basins (DTLBs) at different stages of landscape evolution have different micro-topographical features that likely influence climate forcing from these landscape types. Through the Next-Generation Ecosystem Experiments (NGEE Arctic) project we seek to improve the representativeness of ecosystem processes within Earth system models by quantifying, through field observations, the climate forcing from ecosystem greenhouse gas and energy fluxes within Arctic DTLBs at different stages of landscape evolution. We are measuring soil greenhouse gas fluxes, near-surface spectral radiation components, plant community composition, and environmental driver variables across a ~3 Km transect that spans three DTLBs of different climate-change relevant ages (from 50 years to more than 3000 years old). Preliminary results show that different environmental conditions (soil moisture, soil temperature, and thaw depth) and plant community composition, driven by micro-topographical features, within a given DTLB have a significant influence on soil CO2 and CH4 fluxes and energy fluxes. Scaling analysis show the influence that the spatial distribution of these micro-topographical features and environmental conditions has on the estimation of climate forcing from any given Arctic DTLB.