Mapping simulated circum-Arctic organic carbon, ground ice, and vulnerability of ice-rich permafrost to degradation

摘要: Permafrost is a large reservoir of soil organic carbon, accounting for about half all the terrestrial storage, almost equivalent to twice atmospheric carbon storage. Hence, permafrost degradation under global warming may induce release substantial amount additional greenhouse gases, leading further warming. In addition gradual through heat conduction, importance abrupt thawing or erosion ice-rich has recently been recognized. Such evolved over long timescale (i.e., tens hundreds thousands years). Although important, knowledge on distribution vulnerability degradation, i.e., location and stored ground ice in permafrost, still limited largely due scarcity accessible situ data. Improving future projections Arctic using Earth System Models will lead better understanding current distribution, which prerequisite conducting climatic biogeochemical assessment that currently constitutes source uncertainty. this study, present-day circum-Arctic distributions (north 50° N) content are produced by new approach combine newly developed conceptual carbon-ice balance model, downscaling technique with topographical hydrological information derived from high-resolution digital elevation model (ETOPO1). The simulated evolution recent 125 thousand years (from Last Interglacial present) at 1° resolution. 0.2° maps downscaled simulations, were reasonable compared observation-based previous maps. These data, together map served as initial boundary condition data improvement projection gas potentially caused degradation.