@article{TanskiLantuitRuttoretal.2017,
  author    = {Tanski, George and Lantuit, Hugues and Ruttor, Saskia and Knoblauch, Christian and Radosavljevic, Boris and Strauß, Jens and Wolter, Juliane and Irrgang, Anna Maria and Ramage, Justine Lucille and Fritz, Michael},
  title     = {Transformation of terrestrial organic matter along thermokarst-affected permafrost coasts in the Arctic},
  series = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man},
  volume    = {581},
  journal   = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man},
  publisher = {Elsevier Science},
  address   = {Amsterdam},
  issn      = {0048-9697},
  doi       = {10.1016/j.scitotenv.2016.12.152},
  pages     = {434 -- 447},
  year      = {2017},
  abstract  = {The changing climate in the Arctic has a profound impact on permafrost coasts, which are subject to intensified thermokarst formation and erosion. Consequently, terrestrial organic matter (OM) is mobilized and transported into the nearshore zone. Yet, little is known about the fate of mobilized OM before and after entering the ocean. In this study we investigated a retrogressive thaw slump (RTS) on Qikiqtaruk - Herschel Island (Yukon coast, Canada). The RTS was classified into an undisturbed, a disturbed (thermokarst-affected) and a nearshore zone and sampled systematically along transects. Samples were analyzed for total and dissolved organic carbon and nitrogen (TOC, DOC, TN, DN), stable carbon isotopes (delta C-13-TOC, delta C-13-DOC), and dissolved inorganic nitrogen (DIN), which were compared between the zones. C/N-ratios, delta C-13 signatures, and ammonium (NH4-N) concentrations were used as indicators for OM degradation along with biomarkers (n-alkanes, n-fatty adds, n-alcohols). Our results show that OM significantly decreases after disturbance with a TOC and DOC loss of 77 and 55\% and a TN and DN loss of 53 and 48\%, respectively. C/N-ratios decrease significantly, whereas NH4-N concentrations slightly increase in freshly thawed material. In the nearshore zone, OM contents are comparable to the disturbed zone. We suggest that the strong decrease in OM is caused by initial dilution with melted massive ice and immediate offshore transport via the thaw stream. In the mudpool and thaw stream, OM is subject to degradation, whereas in the slump floor the nitrogen decrease is caused by recolonizing vegetation. Within the nearshore zone of the ocean, heavier portions of OM are directly buried in marine sediments close to shore. We conclude that RTS have profound impacts on coastal environments in the Arctic. They mobilize nutrients from permafrost, substantially decrease OM contents and provide fresh water and nutrients at a point source.},
  language  = {en}
}
@article{StraussSchirrmeisterGrosseetal.2017,
  author    = {Strauss, Jens and Schirrmeister, Lutz and Grosse, Guido and Fortier, Daniel and Hugelius, Gustaf and Knoblauch, Christian and Romanovsky, Vladimir E. and Schadel, Christina and von Deimling, Thomas Schneider and Schuur, Edward A. G. and Shmelev, Denis and Ulrich, Mathias and Veremeeva, Alexandra},
  title     = {Deep Yedoma permafrost: A synthesis of depositional characteristics and carbon vulnerability},
  series = {Earth science reviews : the international geological journal bridging the gap between research articles and textbooks},
  volume    = {172},
  journal   = {Earth science reviews : the international geological journal bridging the gap between research articles and textbooks},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0012-8252},
  doi       = {10.1016/j.earscirev.2017.07.007},
  pages     = {75 -- 86},
  year      = {2017},
  abstract  = {Permafrost is a distinct feature of the terrestrial Arctic and is vulnerable to climate warming. Permafrost degrades in different ways, including deepening of a seasonally unfrozen surface and localized but rapid development of deep thaw features. Pleistocene ice-rich permafrost with syngenetic ice-wedges, termed Yedoma deposits, are widespread in Siberia, Alaska, and Yukon, Canada and may be especially prone to rapid-thaw processes. Freeze-locked organic matter in such deposits can be re-mobilized on short time-scales and contribute to a carbon-cycle climate feedback. Here we synthesize the characteristics and vulnerability of Yedoma deposits by synthesizing studies on the Yedoma origin and the associated organic carbon pool. We suggest that Yedoma deposits accumulated under periglacial weathering, transport, and deposition dynamics in non-glaciated regions during the late Pleistocene until the beginning of late glacial warming. The deposits formed due to a combination of aeolian, colluvial, nival, and alluvial deposition and simultaneous ground ice accumulation. We found up to 130 gigatons organic carbon in Yedoma, parts of which are well-preserved and available for fast decomposition after thaw. Based on incubation experiments, up to 10\% of the Yedoma carbon is considered especially decomposable and may be released upon thaw. The substantial amount of ground ice in Yedoma makes it highly vulnerable to disturbances such as thermokarst and thermo-erosion processes. Mobilization of permafrost carbon is expected to increase under future climate warming. Our synthesis results underline the need of accounting for Yedoma carbon stocks in next generation Earth-System-Models for a more complete representation of the permafrost-carbon feedback.},
  language  = {en}
}