Widespread release of old carbon across the Siberian Arctic echoed by its large rivers ...

• Main Authors: Gustafsson, Örjan, van Dongen, Bart, Vonk, Jorien, Dudarev, Oleg V., Semiletov, Igor P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2011
• Subjects: Arctic; permafrost; Tundra; Alaska
• Online Access: https://dx.doi.org/10.3929/ethz-b-000041948; http://hdl.handle.net/20.500.11850/41948

Over decadal-centennial timescales, only a few mechanisms in the carbon-climate system could cause a massive net redistribution of carbon from land and ocean systems to the atmosphere in response to climate warming. The largest such climate-vulnerable carbon pool is the old organic carbon (OC) stored in Arctic permafrost (perennially frozen) soils. Climate warming, both predicted and now observed to be the strongest globally in the Eurasian Arctic and Alaska, causes thaw-release of old permafrost carbon from local tundra sites. However, a central challenge for the assessment of the general vulnerability of this old OC pool is to deduce any signal integrating its release over larger scales. Here we examine radiocarbon measurements of molecular soil markers exported by the five Great Russian-Arctic Rivers (Ob. Yenisey, Lena, Indigirka and Kolyma), employed as natural integrators of carbon release processes in their watersheds. The signals held in estuarine surface sediments revealed that average radiocarbon ... : Biogeosciences, 8 (6) ...