The Arctic is warming much faster than other regions on Earth. Recent amplified Arctic warming has exerted irreversible impacts on pan-Arctic terrestrial hydrology and the ecosystem. Specifically, the Arctic warming has deepened the active layer and caused permafrost to thaw, releasing a large amount of soil carbon into the atmosphere as greenhouse gases (e.g., CO2 and CH4), potentially accelerating climate warming. Meanwhile, the deepened active layer makes nutrients previously locked in permafrost soils available for microbial decomposition and accessible to plants, thus accelerating plant growth and sequestering more carbon from the atmosphere. In addition, permafrost, acting as an impermeable bottom boundary, inhibits downward water flux. Permafrost thaw then changes the lower boundary condition of soil water percolation, increasing subsurface drainage flux and thus altering soil moisture redistribution and water table. On the one hand, the changing water table alters anaerobic conditions and thus the ratio of CO2 to CH4 in total carbon emissions. On the other hand, the changing permafrost hydrology directly impacts the terrestrial lateral transport of water and carbon to the ocean. Thus, quantitatively characterizing water-carbon interactions across scales is critical to understanding the high-latitude water-carbon-climate feedback.

This session seeks contributions on high-latitude water and carbon cycles across spatial scales with various approaches, including modeling, remote sensing, and machine learning techniques. We particularly welcome papers that discuss the hydrological and hydro-biogeochemical impacts of climate warming on high-latitude permafrost regions.

Submitters:  Jing Tao, LBNL, Berkeley, CA and Jennifer D. Watts, Woodwell Climate Research Center, Falmouth, MA