Small watersheds may play a disproportionate role in arctic land-ocean fluxes

Abstract

While over 99% of coastal arctic rivers drain small catchments, future projections of land-ocean fluxes are based on data from large rivers. We encourage inclusion of and increased focus on smaller catchments to support representative assessments of arctic ecosystem change.

Fig. 1. Coastal arctic watersheds.

Nearly all northern catchments flowing into the Arctic Ocean (A) are smaller than 1000 km². In these small catchments, climate warming occurs more than two times faster than the larger catchments to the south. Northern catchments (B) have high coverage of ice wedge polygon terrain, glacial coverage, and soil carbon stocks, and are often data poor. Warming leads to (C) melting of ground ice and increased hydrological drainage and thaw and decomposition of carbon. Both processes increase transport and emission of carbon, accelerating greenhouse gas emissions. Polygon landscape images from ref. .