“…This flux is 4 orders of magnitude lower than the tDOC supply from the Mackenzie River specified as boundary conditions in the model (2.54 Tg C yr −1 ). Similarly, tDOC eroded from permafrost stored in the North American shores accounts for only ∼ 0.5-1.6 × 10 −4 Tg C yr −1 (Tanski et al, 2016;Ping et al, 2011, using a DOC : particulate organic carbon, POC, ratio of 1 : 900 as in Tanski et al, 2016) to ∼ 2 × 10 −3 Tg C yr −1 (McGuire et al, 2009). With regard to these flux values, tDOC originating from both melted sea ice and eroded permafrost, not taken into account in the model, are hence not believed to explain the model-satellite discrepancies (Fig.…”