@article{WetterichRudayaKuznetsovetal.2019,
  author    = {Wetterich, Sebastian and Rudaya, Natalia and Kuznetsov, Vladislav and Maksimov, Fedor and Opel, Thomas and Meyer, Hanno and G{\"u}nther, Frank and Bobrov, Anatoly and Raschke, Elena and Zimmermann, Heike Hildegard and Strauss, Jens and Starikova, Anna and Fuchs, Margret and Schirrmeister, Lutz},
  title     = {Ice Complex formation on Bol'shoy Lyakhovsky Island (New Siberian Archipelago, East Siberian Arctic) since about 200 ka},
  series = {Quaternary research : an interdisciplinary journal},
  volume    = {92},
  journal   = {Quaternary research : an interdisciplinary journal},
  number    = {2},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {0033-5894},
  doi       = {10.1017/qua.2019.6},
  pages     = {530 -- 548},
  year      = {2019},
  abstract  = {Late Quaternary landscapes of unglaciated Beringia were largely shaped by ice-wedge polygon tundra. Ice Complex (IC) strata preserve such ancient polygon formations. Here we report on the Yukagir IC from Bol'shoy Lyakhovsky Island in northeastern Siberia and suggest that new radioisotope disequilibria (230Th/U) dates of the Yukagir IC peat confirm its formation during the Marine Oxygen Isotope Stage (MIS) 7a-c interglacial period. The preservation of the ice-rich Yukagir IC proves its resilience to last interglacial and late glacial-Holocene warming. This study compares the Yukagir IC to IC strata of MIS 5, MIS 3, and MIS 2 ages exposed on Bol'shoy Lyakhovsky Island. Besides high intrasedimental ice content and syngenetic ice wedges intersecting silts, sandy silts, the Yukagir IC is characterized by high organic matter (OM) accumulation and low OM decomposition of a distinctive Drepanocladus moss-peat. The Yukagir IC pollen data reveal grass-shrub-moss tundra indicating rather wet summer conditions similar to modern ones. The stable isotope composition of Yukagir IC wedge ice is similar to those of the MIS 5 and MIS 3 ICs pointing to similar atmospheric moisture generation and transport patterns in winter. IC data from glacial and interglacial periods provide insights into permafrost and climate dynamics since about 200 ka.},
  language  = {en}
}
@article{OpelMurtonWetterichetal.2019,
  author    = {Opel, Thomas and Murton, Julian B. and Wetterich, Sebastian and Meyer, Hanno and Ashastina, Kseniia and G{\"u}nther, Frank and Grotheer, Hendrik and Mollenhauer, Gesine and Danilov, Petr P. and Boeskorov, Vasily and Savvinov, Grigoriy N. and Schirrmeister, Lutz},
  title     = {Past climate and continentality inferred from ice wedges at Batagay Highlands, interior Yakutia},
  series = {Climate of the past : an interactive open access journal of the European Geosciences Union},
  volume    = {15},
  journal   = {Climate of the past : an interactive open access journal of the European Geosciences Union},
  number    = {4},
  publisher = {Copernicus},
  address   = {G{\"o}ttingen},
  issn      = {1814-9324},
  doi       = {10.5194/cp-15-1443-2019},
  pages     = {1443 -- 1461},
  year      = {2019},
  abstract  = {Ice wedges in the Yana Highlands of interior Yakutia - the most continental region of the Northern Hemisphere - were investigated to elucidate changes in winter climate and continentality that have taken place since the Middle Pleistocene. The Batagay megaslump exposes ice wedges and composite wedges that were sampled from three cryostratigraphic units: the lower ice complex of likely pre-Marine Isotope Stage (MIS) 6 age, the upper ice complex (Yedoma) and the upper sand unit (both MIS 3 to 2). A terrace of the nearby Adycha River provides a Late Holocene (MIS 1) ice wedge that serves as a modern reference for interpretation. The stable-isotope composition of ice wedges in the MIS 3 upper ice complex at Batagay is more depleted (mean delta O-18 about -35 parts per thousand) than those from 17 other ice-wedge study sites across coastal and central Yakutia. This observation points to lower winter temperatures and therefore higher continentality in the Yana Highlands during MIS 3. Likewise, more depleted isotope values are found in Holocene wedge ice (mean delta O-18 about -29 parts per thousand) compared to other sites in Yakutia. Ice-wedge isotopic signatures of the lower ice complex mean delta O-18 about -33 parts per thousand) and of the MIS 3-2 upper sand unit (mean delta O-18 from about -33 parts per thousand to -30 parts per thousand) are less distinctive regionally. The latter unit preserves traces of fast formation in rapidly accumulating sand sheets and of post-depositional isotopic fractionation.},
  language  = {en}
}
@article{WetterichSchirrmeisteNazarovaetal.2018,
  author    = {Wetterich, Sebastian and Schirrmeiste, Lutz and Nazarova, Larisa B. and Palagushkina, Olga and Bobrov, Anatoly and Pogosyan, Lilit and Savelieva, Larisa and Syrykh, Liudmila and Matthes, Heidrun and Fritz, Michael and G{\"u}nther, Frank and Opel, Thomas and Meyer, Hanno},
  title     = {Holocene thermokarst and pingo development in the Kolyma Lowland (NE Siberia)},
  series = {Permafrost and Periglacial Processes},
  volume    = {29},
  journal   = {Permafrost and Periglacial Processes},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1045-6740},
  doi       = {10.1002/ppp.1979},
  pages     = {182 -- 198},
  year      = {2018},
  abstract  = {Ground ice and sedimentary records of a pingo exposure reveal insights into Holocene permafrost, landscape and climate dynamics. Early to mid-Holocene thermokarst lake deposits contain rich floral and faunal paleoassemblages, which indicate lake shrinkage and decreasing summer temperatures (chironomid-based T-July) from 10.5 to 3.5 cal kyr BP with the warmest period between 10.5 and 8 cal kyr BP. Talik refreezing and pingo growth started about 3.5 cal kyr BP after disappearance of the lake. The isotopic composition of the pingo ice (delta O-18 - 17.1 +/- 0.6 parts per thousand, delta D -144.5 +/- 3.4 parts per thousand, slope 5.85, deuterium excess -7.7 +/- 1.5 parts per thousand) point to the initial stage of closed-system freezing captured in the record. A differing isotopic composition within the massive ice body was found (delta O-18 - 21.3 +/- 1.4 parts per thousand, delta D -165 +/- 11.5 parts per thousand, slope 8.13, deuterium excess 4.9 +/- 3.2 parts per thousand), probably related to the infill of dilation cracks by surface water with quasi-meteoric signature. Currently inactive syngenetic ice wedges formed in the thermokarst basin after lake drainage. The pingo preserves traces of permafrost response to climate variations in terms of ground-ice degradation (thermokarst) during the early and mid-Holocene, and aggradation (wedge-ice and pingo-ice growth) during the late Holocene.},
  language  = {en}
}
@misc{FritzOpelTanskietal.2015,
  author    = {Fritz, Michael and Opel, Thomas and Tanski, George and Herzschuh, Ulrike and Meyer, Hanno and Eulenburg, A. and Lantuit, Hugues},
  title     = {Dissolved organic carbon (DOC) in Arctic ground ice},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {493},
  issn      = {1866-8372},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-408155},
  pages     = {16},
  year      = {2015},
  abstract  = {Thermal permafrost degradation and coastal erosion in the Arctic remobilize substantial amounts of organic carbon (OC) and nutrients which have accumulated in late Pleistocene and Holocene unconsolidated deposits. Permafrost vulnerability to thaw subsidence, collapsing coastlines and irreversible landscape change are largely due to the presence of large amounts of massive ground ice such as ice wedges. However, ground ice has not, until now, been considered to be a source of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC) and other elements which are important for ecosystems and carbon cycling. Here we show, using biogeochemical data from a large number of different ice bodies throughout the Arctic, that ice wedges have the greatest potential for DOC storage, with a maximum of 28.6 mg L-1 (mean: 9.6 mg L-1). Variation in DOC concentration is positively correlated with and explained by the concentrations and relative amounts of typically terrestrial cations such as Mg2+ and K+. DOC sequestration into ground ice was more effective during the late Pleistocene than during the Holocene, which can be explained by rapid sediment and OC accumulation, the prevalence of more easily degradable vegetation and immediate incorporation into permafrost. We assume that pristine snowmelt is able to leach considerable amounts of well-preserved and highly bioavailable DOC as well as other elements from surface sediments, which are rapidly frozen and stored in ground ice, especially in ice wedges, even before further degradation. We found that ice wedges in the Yedoma region represent a significant DOC (45.2 Tg) and DIC (33.6 Tg) pool in permafrost areas and a freshwater reservoir of 4200 km(2). This study underlines the need to discriminate between particulate OC and DOC to assess the availability and vulnerability of the permafrost car-bon pool for ecosystems and climate feedback upon mobilization.},
  language  = {en}
}
@article{FritzOpelTanskietal.2015,
  author    = {Fritz, Michael and Opel, Thomas and Tanski, George and Herzschuh, Ulrike and Meyer, H. and Eulenburg, A. and Lantuit, Hugues},
  title     = {Dissolved organic carbon (DOC) in Arctic ground ice},
  series = {The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union},
  volume    = {9},
  journal   = {The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union},
  number    = {2},
  publisher = {Copernicus},
  address   = {G{\"o}ttingen},
  issn      = {1994-0416},
  doi       = {10.5194/tc-9-737-2015},
  pages     = {737 -- 752},
  year      = {2015},
  abstract  = {Thermal permafrost degradation and coastal erosion in the Arctic remobilize substantial amounts of organic carbon (OC) and nutrients which have accumulated in late Pleistocene and Holocene unconsolidated deposits. Permafrost vulnerability to thaw subsidence, collapsing coastlines and irreversible landscape change are largely due to the presence of large amounts of massive ground ice such as ice wedges. However, ground ice has not, until now, been considered to be a source of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC) and other elements which are important for ecosystems and carbon cycling. Here we show, using biogeochemical data from a large number of different ice bodies throughout the Arctic, that ice wedges have the greatest potential for DOC storage, with a maximum of 28.6 mg L-1 (mean: 9.6 mg L-1). Variation in DOC concentration is positively correlated with and explained by the concentrations and relative amounts of typically terrestrial cations such as Mg2+ and K+. DOC sequestration into ground ice was more effective during the late Pleistocene than during the Holocene, which can be explained by rapid sediment and OC accumulation, the prevalence of more easily degradable vegetation and immediate incorporation into permafrost. We assume that pristine snowmelt is able to leach considerable amounts of well-preserved and highly bioavailable DOC as well as other elements from surface sediments, which are rapidly frozen and stored in ground ice, especially in ice wedges, even before further degradation. We found that ice wedges in the Yedoma region represent a significant DOC (45.2 Tg) and DIC (33.6 Tg) pool in permafrost areas and a freshwater reservoir of 4200 km(2). This study underlines the need to discriminate between particulate OC and DOC to assess the availability and vulnerability of the permafrost car-bon pool for ecosystems and climate feedback upon mobilization.},
  language  = {en}
}